a Syarat Tumbuh Tanaman padi dapat hidup baik didaerah yang berhawa panas dan banyak mengandung uap air. Curah hujan yang baik rata-rata 200 mm per bulan atau lebih, dengan distribusi. 4. selama 4 bulan, curah hujan yang dikehendaki per tahun sekitar 1500 -2000 mm. Suhu yang baik untuk pertumbuhan tanaman padi 23 °C. Jenisjenis bibit dari IRRI ini di Indonesia disebut padi unggul baru (PUB). Pada tahun 1966, IR-8 mulai disebarkan ke Asia diikuti oleh penyebaran IR-5 pada tahun 1967. Pada tahun 1968 di India, Pakistan, Sri Lanka, Filipina, Malaysia, Taiwan, Vietnam, dan Indonesia telah dilaksanakan penanaman padi jenis IR atau PUB secara luas di masyarakat. TERBAIK Hub. (WA), Benih Bibit Padi Unggul IR 64 Beli Benih Bibit Padi Unggul IR 64, Benih Bibit Padi Unggul IR 64 Murah, Benih Bibit Padi Unggul IR 64 Online, Benih Bibit Padi 2Penggunaan bibit unggul seperti IR 64, mekongga, ciherang, dan inpari untuk meningkatkan produktivitas dalam usahatani 3 Potensi hasil tinggi, tahan terhadap hama dan penyakit, toleran terhadap cekaman lingkungan, 2 Tungro merupakan virus atau penyakit yang dapat menyerang tanaman padi dengan cepat dan secara luas 3 Pengendalian penyakit Pengadaanbibit secara okulasi ini sudah banyak dikembangkan, terutama dalam usaha menciptakan bibit-bibit jeruk unggul yang cepat menghasilkan dan tahan terhadap kemungkinan serangan hama serta penyakit (AAK, 2004). Secara umum, bibit okulasi dapat dikatakan paling diminati karena merupakan perpaduan dua sifat unggul tetuanya. Menggunakanpendekatan Pengelolaan Tanaman Terpadu (PTT) pada Padi Sawah, dengan komponen : penggunaan varietas padi unggul baru yang diminati petani setempat, menggunakan benih bermutu dan menanam bibit umur muda (15 hari setelah hambur), menanam 1-3 batang per rumpun tanaman, menggunakan cara tanam jajar legowo, pemupukan N dengan menggunakan . CIRI-CIRI PADI SAWAH IR-64 Penulis Nurman Ihsan, SP THL TBPP DEPTAN di BANTEN Salah satu varietas padi yang saat ini paling banyak ditanam petani selain varietas Ciherang adalah varietas IR64. Varietas ini dilepas pemerintah sekitar tahun 1986. Ketika kita membeli benih padi di kios-kios, maka besar kemungkinan hanya ada 2 jenis padi saja, kalau tidak padi ciherang, ya padi IR64 ini. Kalau kita melihat sosok padi IR64 di sawah, maka biasanya secara “kasat mata” dapat kita bedakan dengan padi lain. Menurut saya, padi IR64 selain sosoknya agak pendek, jumlah anakkan banyak, dan bulirnya yang agak besar dan ramping, padi ini terlihat “mekar” dibandingkan dengan padi lain. Menurut saya sosok padi yang “mekar” inilah yang menjadi ciri khas padi IR64. Di daerah Surabaya, Sidoarjo dan sekitarnya, beras IR64 ini dikenal dengan nama beras bengawan. Ciri-ciri fisiknya panjang dan ramping, sedangkan warnanya putih susu. Beras jenis ini cocok untuk makanan yang berkuah. Kalau di Tasikmalaya, beras dari IR64 ini dinamakan beras panjang. Berikut ini adalah ciri-ciri varietas padi R64, sumber BB padi IR 64, Rice Varieties – Padi Sawah Asal persilangan IR5657/IR2061 Kelompok Padi Sawah Nomor Seleksi IR18348-36-3-3 Golongan Cere Umur tanaman 110-120 hari Bentuk tanaman Tegak Tinggi tanaman 85 cm Anakan produktif 20-35 batang Warna kaki Hijau Warna batang Hijau Warna telinga daun Tidak berwarna Warna lidah daun Tidak berwarna Warna daun Hijau Permukaan daun Kasar Posisi daun Tegak Daun bendera Tegak Bentuk gabah Ramping, panjang Warna gabah Kuning bersih Kerontokan Tahan Kerebahan Tahan Tekstur nasi Pulen Kadar amilosa 24,1% Indeks glikemik 70 Bobot 1000 butir 27 gram Rata-rata hasil 5,0 t/ha Potensi hasil 6,0 t/ha Ketahanan terhadap Hama Tahan wereng coklat biotipe 1,2, dan agak tahan wereng coklat biotipe 3 Ketahanan terhadap penyakit Agak tahan hawar daun bakteri strain IV tahan virus kerdil rumput Pemulia Introduksi dari IRRI Di lepas tahun 1986 About NURMAN IHSAN Bila cinta kepada seseorang saja, di hati penuh kerinduan. Apalagi bila kita dapatkan cinta ALLOH SWT. Ini prestasi seorang hamba. Prestasi hidup. Dan prestasi terbesar. Oleh sebab itu, rebutlah cinta itu,,, This entry was posted in BENIH UNGGUL PADI. Bookmark the permalink. – Varietas IR 64 pertama kali dilounching tahun 1986 oleh presiden Soeharto. Setelah peluncurannya, IR64 langsung menjadi idola di petani karena sifatnya yang adaptif dan mudah budidayanya oleh para petani. IR 64 di eranya juga termasuk jenis padi yang tahan terhadap virus kerdil rumput yang dibawa oleh WBC type 1 dan 2. Padi IR64 merupakan jenis varietas yang memiliki batang kurang lebih 85 cm. Padi varietas ini juga memiliki anakan produktif sebanyak 11 sampai 20 dengan nilai rata-rata adalah 14,83. Dengan bobot 1000 butir kurang lebih 27 g Puslittan 2013. Djunainah 1993 dalam buku Deskripsi Varietas Unggul Padi menyebut bahwa varietas IR64 sangat digemari oleh para petani dan konsumen karena rasa nasinya enak, umur genjah 110-125 hari dan potensi hasil yang tinggi yakni mencapai 5 ton/ha. Varietas IR64 merupakan salah satu varietas padi sawah yang hemat dalam mengkonsumsi air. Konsumsi air bervariasi dengan kisaran 1/tanaman. Perbedaan ini disebabkan oleh adanya perbedaan morfologi maupun karakter fisiologi antar genotipe. Menurut Supijatno 2012, varietas IR64 mengkonsumsi air sebesar l/tanaman dan konsumsi ini adalah yang terendah di antara varietas lain. Varietas IR64 adalah padi yang berasal dari IRRI International Rice Research Institute dan pertama kali diintroduksi ke Indonesia pada tahun 1986 BBPTP 2008. Varietas IR64 dipilih sebagai tetua persilangan karena IR64 merupakan varietas padi unggul nasional, memiliki karakter -karakter yang banyak disukai petani. Namun padi ini memiliki kekurangan karena tidak dapat tumbuh dengan baik jika ditanam pada lahan sawah irigasi dataran rendah yang mengandung konsentrasi logam Fe tinggi. Karakter tinggi tanaman antara 65-85 cm dengan umur berbunga 59-63 hari, anakan produktif 11-20 anakan, umur tanaman 81-98 hari, bobot 1000 biji padi mencapai 21 gram. Sementara jumlah gabah permalai sebesar 35-105. Namun seiringnya waktu karena IR64 terlalu sering ditanam dengan prosentase luasan tinggi maka muncul WBC biotype 3 maka patahlah kejayaan IR64. Varietas ini rentan terhadap virus tungro, WBC biotype 3 dan agak rentan terhadap kresek. Sekalipun demikian, jenis beras saat ini sesungguhnya juga berasal dari persilangan dengan IR64. Editor Romandhon High-yielding varieties developed in the 1960s and 1970s at the International Rice Research Institute IRRI and elsewhere benefited farmers and the public, ultimately increasing yields and reducing the cost of rice to consumers. Most of these varieties, however, did not have the optimum cooking quality that was possessed by many of the traditional varieties they replaced. In 1985, the IRRI-developed indica variety IR64 was released in the Philippines. In addition to its high yield, early maturity and disease resistance, it had excellent cooking quality, matching that of the best varieties available. These merits resulted in its rapid spread and cultivation on over 10 million ha in the two decades after it was released. It has intermediate amylose content and gelatinization temperature, and good taste. It is resistant to blast and bacterial blight diseases, and to brown planthopper. Because of its success as a variety, it has been used extensively in scientific studies and has been well-characterized genetically. Many valuable genes have been introduced into IR64 through backcross breeding and it has been used in thousands of crosses. Its area of cultivation has declined in the past 10 years, but it has been replaced by a new generation of high-quality varieties that are mostly its progeny or relatives. Continued basic studies on IR64 and related varieties should help in unraveling the complex genetic control of yield and other desirable traits that are prized by rice farmers and may be subject to copyright. Discover the world's research25+ million members160+ million publication billion citationsJoin for free R E V I E W Open AccessIR64 a high-quality and high-yieldingmega varietyDavid J. Mackill1*and Gurdev S. Khush2AbstractHigh-yielding varieties developed in the 1960s and 1970s at the International Rice Research Institute IRRI andelsewhere benefited farmers and the public, ultimately increasing yields and reducing the cost of rice to of these varieties, however, did not have the optimum cooking quality that was possessed by many of thetraditional varieties they replaced. In 1985, the IRRI-developed indica variety IR64 was released in the Philippines. Inaddition to its high yield, early maturity and disease resistance, it had excellent cooking quality, matching that ofthe best varieties available. These merits resulted in its rapid spread and cultivation on over 10 million ha in the twodecades after it was released. It has intermediate amylose content and gelatinization temperature, and good is resistant to blast and bacterial blight diseases, and to brown planthopper. Because of its success as a variety, ithas been used extensively in scientific studies and has been well-characterized genetically. Many valuable geneshave been introduced into IR64 through backcross breeding and it has been used in thousands of crosses. Its areaof cultivation has declined in the past 10 years, but it has been replaced by a new generation of high-qualityvarieties that are mostly its progeny or relatives. Continued basic studies on IR64 and related varieties should helpin unraveling the complex genetic control of yield and other desirable traits that are prized by rice farmers November 2016, the International Rice Research Insti-tute IRRI and others commemorated the 50th anniversaryof the release of IR8, its first developed variety and a begin-ning of the Green Revolution in rice variety established the basic plant type of the high-yielding varieties HYVs that have now spread over mostrice growing had a very high grain yield, but also a number of de-fects, most importantly, poor grain quality, lack of diseaseand insect resistance, and late maturity. The varietiessubsequently developed and released over the next twodecades improved greatly on these traits Khush 1999.During the early 1980s, one of the most popular varietiesgrown was IR36. In addition to its disease and insect re-sistance, it achieved its high yield in a period of only111 days from seed to seed, compared to 130 days for IR8Khush and Virk 2005. It spread rapidly and wasestimated to be planted on more than 10 million ha dur-ing the much improved over IR8, IR36 still lacked thequality of the best varieties grown in the Philippines andIndonesia before the Green Revolution. IR64, released inthe Philippines in 1985, represented a breakthrough incombining excellent palatability of cooked rice with theother traits found in previous IRRI HYVs. IR64 replacedIR36 in most growing areas and spread rapidly in newareas. Because of its wide adaptation, early maturity, andimproved quality, it became a standard for high-qualityrice and was highly desired by the rice industry. Becauseof its popularity, it has been used widely as a representa-tive indica variety in research studies. It has also beenused extensively as a parent in breeding programs, andto develop populations for genetic this article, we describe the development of IR64and its major characteristics. We also discuss the use ofthis variety in further breeding and rice research.* Correspondence djmackill Inc. and Department of Plant Sciences, University of California, Davis,CA 95616, USAFull list of author information is available at the end of the article© The Authors. 2018 Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original authors and the source, provide a link tothe Creative Commons license, and indicate if changes were and Khush Rice 2018 1118 courtesy of Springer Nature, terms of use apply. Rights reserved. ReviewBreeding history, including parentage and selectionhistory, evaluation and releaseThe breeding history of IR64 is summarized in Khushand Virk 2005. The breeding program at IRRI focusedon combining the different traits desired by farmers, in-cluding high yield, resistance to biotic and abioticstresses, early maturity, and improved grain quality. TheGenetic Evaluation and Utilization GEU program wasformulated at IRRI to focus research efforts on combin-ing these traits through interdisciplinary collaborationKhush and Coffman 1977. In segregating generationsand in evaluation of fixed lines, plants and breeding lineswere evaluated for these traits either in the pedigreebreeding nursery or special screening nurseries. This im-proved the chance of combining multiple traits into asingle cross of IR5657-33-2-1/IR2061-465-1-5-5, wasmade in early 1977 and was designated IR18348. The fe-male parent was noted for its good cooking qualityintermediate amylose, as well as having some toleranceto salinity. The male parent was a high-yielding breedingline derived from a highly productive cross that resultedin a number of other varieties from sister lines, includ-ing IR28, IR29 and IR34. The full pedigree Fig. 1 showsthe derivation of IR64 from 19 traditional rice F2 population was evaluated in 1978, and thepedigree method of breeding was followed in the F3 andF4 populations, grown in 1979. The breeding lineIR18348-36-3-3 resulted from the bulk harvest of a F5family in 1980, and was subsequently evaluated in yieldtrials in 1981–83 at IRRI, as well as in the PhilippineNational Trials. It out-yielded IR36 by 21% in these trialsIRRI 1986. It was released by the Philippine Seed Boardwith the designation IR64’in 1985, and this designationhas been subsequently used by IRRI IRRI 1986.The early varieties developed at IRRI were high yieldingand had disease and insect resistance, but their grain qualitywas inferior to the best available varieties. At the time, thestandard for grain quality in the Philippines was the varietyBPI-76 and its sister line BPI-121, derived from the crossFortuna/Seraup Besar 15 Cada and Escuro 1972. The par-ent variety Fortuna is from the USA, and Seraup Besar 15was originally introduced from Malaysia. BPI-76 was re-leased in 1960 in the Philippines, and non-photoperiod sen-sitive selections, BPI-76 and BPI-76-1, were alsoreleased Dalrymple 1978. Another popular variety notedfor its quality was C4-63, and it was derived from the crossPeta/BPI-76. Before IR64, C4-63 was considered one of themain high-quality varieties in the Philippines. In 1970, agreen-base C4-63 was released to replace the original seedstocks of C4-63. Because of its good eating quality inter-mediate amylose content it had spread in Indonesia,Malaysia, and Burma Yoshida 1981. Rice was even widelymarketed under the C4 name up to the 1980s; however,many of the market samples actually turned out to be othervarieties or mixtures of varieties with inferior quality thatwere being grown by farmers Juliano et al. 1989.BPI-121-407 is considered the most likely contributorof superior quality in the pedigree of IR64, althoughBPI-76 is also in its pedigree. BPI-121-407 is a short-statured breeding line with superior quality, and was se-lected as an induced mutant of the original BPI-121Cada and Escuro 1972. In the advanced evaluation ofFig. 1 Pedigree of IR64 showing the ultimate landraces in its ancestry Khush and Virk 2005Mackill and Khush Rice 2018 1118 Page 2 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. the breeding line IR18348-36-3-3 at IRRI, taste panelswere used to ensure that the quality of BPI-76 or BPI-121 was captured. Taste panels were also applied in thegovernment of the Philippines rice program to assist inproviding the data for release of this and impactThe major breakthrough in the development of IR64was the combination of the high yield and diseaseand insect resistance of earlier IRRI varieties with thesuperior grain quality associated with varieties likeBPI-76 and C4-63. It’s first release was by the Philip-pine government in 1985. It was also released in thefollowing countries Bhutan, Burkina Faso as FKR42,Cambodia, China, Ecuador as NIAP11, Gambia,India, Indonesia, Mauritania, Mozambique, andVietnam as OM89 Khush and Virk 2005. Its wideadaptation is notable, and it became widely grown inSoutheast and South Asia. It is also noted to be welladapted to the Sahelian regions of West AfricaDevries et al. 2011;JuliaandDingkuhn2013.By 1995, IR64 was already estimated to be grown on 8million ha Khush 1995, and by the turn of the centurythis rose to over 10 million ha. The long persistence ofIR64 in farmers’fields after its release was attributed to itsexcellent eating quality Champagne et al. 2010. The areaof production gradually declined in the Philippines duringthe period 2000–2007, partly due to pressure from tungrodisease Laborte et al. 2015. Indonesia was a major pro-ducer of IR64, which was grown on more than 40% of itstotal area for around a decade Fig. 2, and was stillpopular in 2009 Brennan and Malabayabas 2011. It isalso widely grown in India. During 1998–2006 IR64accounted for over 10% of the breeder seed produced inIndia and was still above 3% in 2015, suggesting that itwas grown on 2–3 million ha annually during the perioddata provided by A. K. Singh.A specific estimate of the impact of this variety hasnot been attempted, even though it is known as the mostpopular variety in terms of area, particularly in tropicalAsia. IR64 has contributed greatly to farmer incomesnot only through higher yields, but through improvedquality that results in higher price and earlier maturitythat allows higher cropping with other IRRI varieties, seed of IR64 was distrib-uted freely to researchers and farmers and no intellec-tual property protection was sought on it or any progenydeveloped from characteristics, including key traitsIR64 is a semidwarf indica rice variety, with average ma-ture plant height of approximately 100 cm in thePhilippines Fig. 3. It is a relatively early duration var-iety, with total growth duration of about 117 daysKhush and Virk 2005. It inherits the same semidwarfsd1 allele as other IRRI semidwarf varieties, ultimatelyderived from Dee-geo-woo-gen. According to Wei et al.2016 it has the loss of function alleles for Hd1 andEhd1, which confer earlier duration and insensitivity tophotoperiod. At the time of its release, IRRI 1986 listedthe valuable traits as resistance to brown planthopperBPH biotypes 1 and 3, green leafhopper GLH, whiteFig. 2 Share of leading varieties in Indonesia during 1985–2009 Brennan and Malabayabas 2011Mackill and Khush Rice 2018 1118 Page 3 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. backed planthopper WBPH, bacterial blight, grassystunt virus; and moderate resistance to blast, BPH bio-type 2, and stem borer. It was the first IRRI variety tocombine intermediate amylose content and intermediategelatinization temperature GT.IR64 has high yield, especially compared to earlier-released IRRI varieties, but not as high as some of thesubsequently released varieties like IR72. Peng et al.2000 list its grain yield as and t ha−1compared to and t ha−1for IR72 in the dryseason at IRRI in 1996 and 1998, respectively. It hashigh grain filling percentage and grain weight, but arelatively low spikelet number per m2Peng et al. 2000.According to Ujiie et al. 2016, IR64 possesses a geneGS3 for grain size and the narrow-leaf gene NAL1 thatimprove grain yields. IR64 is considered a typical high-tillering indica type cultivar, in contrast to the “newplant type”NPT varieties that have lower tillering butlarge tiller and panicle size Okami et al. 2015.IR64 has relatively durable resistance to BPH, and it isknown to carry the major gene Bph1. However, it is re-ported to have better resistance than other varieties carry-ing Bph1 andhasgoodfieldresistancetothepest,exhibiting antiobiosis, antixenosis and tolerance Cohen etal. 1997. This is partly attributed to its possessing add-itional QTLs controlling BPH resistance which confergreater durability of the resistance Alam and Cohen 1998.IR64 has very good levels of resistance to blast disease,including major-gene resistance and partial resistanceBastiaans and Roumen 1993; Grand et al. 2012;Roumen1992. Sallaud et al. 2003 reported six resistance genes,designated Pi25t, Pi-27t, Pi29t, Pi30t, Pi31t, andPi32t. It also has resistance genes Pita Lee et al. 2011and Pi20 Khush and Virk 2005, as well as Pi33 onchromosome 8 which was derived from O. rufipogon ac-cession IRGC101508, sometimes referred to as O. nivarain its pedigree Ballini et al. 2007; Berruyer et al. 2003.Sreewongchai et al. 2010 found that IR64 has broad re-sistance to blast disease in Thailand and this was con-ferred mainly by QTLs on chromosomes 2 and 12. It wasalso resistant in a blast hotspot in India Thakur et Kongprakhon et al. 2010 identified QTLs thatmay correspond to Pi25 chromosome 2, Pi29 chromo-some 8, and Pi28 chromosome 10.IR64 is resistant to Bacterial Blight BB diseasecaused by Xanthomonas oryzae pv. oryzae and pos-sesses the major gene Xa4 for resistance Adhikari et Khush and Virk 2005. The gene is thought toconfer additional agronomic benefits in addition to BBresistance Hu et al. 2017. It is also resistant against Af-rican strains of X. oryzae, and several QTLs for resist-ance were identified Djedatin et al. 2016.IR64 is susceptible to tungro disease, including RiceTungro Spherical Virus RTSV Lee et al. 2010 and RiceTungro Bacilliform Virus RTBV Zenna et al. 2006.IR64 was developed primarily for irrigated riceproduction, and abiotic stress resistance was not an ob-jective. While it is generally considered susceptible toabiotic stresses, it has been widely grown in more favor-able rainfed situations and under mildly is considered susceptible to drought stress andyield reductions can be considerable Anantha et al. 2016.Yields under aerobic conditions favorable upland arealso relatively low Zhao et al. 2010. Vikram et al. 2015attributed drought susceptibility of many modern high-yielding varieties to linkage between a drought susceptibil-ity QTL and the semidwarf gene sd1. IR64 has a relativelyshallow root system and low root length density Henry etal. 2011; Shrestha et al. 2014. Under water stress, IR64has relatively low water uptake rate Gowda et al. 2012.IR64 is considered sensitive to heat Coast et al. 2016;Gonzalez-Schain et al. 2016; Shanmugavadivel et al. 2017;Ye et al. 2015, although this has not been reported as aproblem with previous or current production environ-ments. However, Jagadish et al. 2008 indicated that IR64is actually moderately tolerant of high temperature atFig. 3 Plot of IR64 growing in the field at IRRI, Los Baños, Philippinesphoto from IRRIMackill and Khush Rice 2018 1118 Page 4 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. flowering. It is also susceptible to Fe toxicity Wu et anaerobic germination Miro and Ismail 2013, andlow temperature at the vegetative stage Chawade et IR64 lacks the P deficiency gene PSTOL1 like anumber of other high-yielding varieties Gamuyao et IR64 was reported to be sensitive to low P condi-tions Mori et al. 2016; Vejchasarn et al. 2016. It is alsorelatively sensitive to Zn deficiency Impa et al. 2013.While IR64 does not possess the submergencetolerancealleleofSUB1, it has some moderate toler-ance to submergence during the vegetative stageSingh et al. 2010; Singh et al. 2013.Grain and market characteristicsIR64 grain has good physical appearance and is a typicallong-grain variety with high head rice yield IRRI 1986.As mentioned above, IR64 was the first IRRI variety tohave both intermediate amylose content and intermedi-ate GT. These traits are considered important for theideal texture of cooked rice, especially for many riceconsumers in South and Southeast Asia. However, thesetwo traits alone do not account for the superior cookingquality of the variety, and methods to evaluate cookingquality are still inadequate aside from laborious sensorymethods Concepcion et al. 2015. This is why the use oftaste panels was essential to identify the superior qualityof texture is mostly controlled by the allele at thewaxy locus Wx on chromosome 6. Among the major al-leles at this locus, IR64 carries the Wxinallele at the waxylocus signifying intermediate amylose content Zhang etal. 2012. However, various sequence features of the Wxgene are associated with grain quality of rice, includingthe number of CT repeats in the 5′untranslated part ofthe gene and the SNPs at specific sites in intron 1, exon 6,and exon 10 Bligh et al. 1998; Bligh et al. 1995; Larkinand Park 2003. Based on the DNA sequence, IR64 hasthe CT17allele of Wx Roferos et al. 2008; CT17and CT20are associated with intermediateamylose and soft to medium hardness Roferos et The SNPs at the Wx locus are G-C-C for intron 1,exon 6 and exon 10, a common haplotype for intermedi-ate amylose varieties Chen et al. 2010.Azucena and IR64 both have intermediate amyloseand intermediate GT, and the doubled haploid popula-tion of the cross between the two was used to identifyQTLs for several grain quality related traits, includingstarch properties measured by Rapid Visco AnalyzerRVA Bao et al. 2002. The study showed that there aregenetic differences for these traits despite both varietieshaving similar amylose content and of the improved quality superiority is from im-proved flavor, including sweet and corn notes Calingacionet al. 2015; Champagne et al. 2010. Reduced yellow color,improved texture and mouthfeel, and superior “sweet”taste were noted in IR64 vs. the lower-quality IRRI-132Champagne et al. 2010 Table 1. Metabolomics analysisshowed very different profiles for IR64 vs. the lower qual-ity variety Apo Calingacion et al. 2015.Calingacion et al. 2014 surveyed grain quality prefer-ences in different countries and regions based on themost popular varieties in each area. However, two coun-tries where IR64 dominated have different preferencesIndonesia and Philippines. These preferences canchange over and genomic characteristicsIR64 has been used extensively in genetic studies of rice,mainly because it represents a high-yielding and high-quality indica variety that is widely adapted to tropicallowland growing conditions. The most well-known map-ping population was a doubled haploid population ofabout 146 lines derived from the cross IR64/AzucenaGuiderdoni et al. 1992, and first used by Huang et al.1997 to map important agronomic traits and by Wu etal. 1997 to map tolerance to Fe toxicity. Other map-ping populations with IR64 as a parent have been devel-oped using both indica and japonica parents. Arecombinant inbred line RIL population of 171 familieswas developed in a cross between IR64 and the wildrelative O. rufipogon and tolerance to Al toxicity wasmapped Nguyen et al. 2003. Reciprocal chromosomesegment substitution lines CSSL were also developedin IR64 and Koshihikari backgrounds to study the inher-itance of grain shape Nagata et al. 2015.The original genome sequence of rice used the japon-ica variety Nipponbare IRGSP 2005. In the first reportof resequencing multiple varieties, IR64 was used among20 diverse varieties, although this only included 100 Mbof the unique fraction of the genome McNally et Schatz et al. 2014 reported whole genome denovo assembly for IR64 as well as the japonica varietyTable 1 Comparison of flavor attributes of high quality IR64and low-quality Apo Calingacion et al. 2015Flavor ApoaIR64aApo IR64Irrigated Drought Irrigated DroughtSweet taste + ++ + + ++ +Corn + + +Sweet aromatic + + +Astringent ++ + + + +Water like metallic ++ + ++ ++ +Sewer/animal ++ ++ ++Sour/silage ++ + + +Hay-like musty ++ ++ ++ +areported from a previous study Champagne et al. 2010Mackill and Khush Rice 2018 1118 Page 5 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. Nipponbare and the aus variety DJ123. The genomecoverage was and included 37,758 genes. IR64was estimated to have 381 genes not present in either ofthe other two varieties, and DJ123 and Nipponbare had297 and 786 genes not found in the other varieties. Jainet al. 2014 also reported whole genome sequencing ofIR64 along with Pokkali and N22, achieving Methylation pattern has also been studied inIR64 and compared with a japonica variety Dianjingyou1and two wild ancestors Li et al. 2012. Gene expressionand identification of functional roles of genes have beencarried out with this model variety, for example droughtresponsive genes Ray et al. 2011, gene expressionchanges during different stages of development Sharmaet al. 2012, and salinity tolerance Wang et al. 2016.Important progenyThe excellent grain quality of IR64 has become the stand-ard for rice quality requirements in a number of of its popularity with farmers, IR64 has been usedwidely as a parent in rice breeding, as a recipient of newgenes through marker-assisted backcrossing and genetictransformation, and as a standard check for basic studiesby many rice researchers. IR64 figured prominently in themapping of many QTLs when genome-wide markers be-came the Philippines, IR64 was replaced by newer var-ieties in the early 2000s mainly due to its susceptibilityto tungro disease. However, the breeders have attemptedto retain the quality traits of IR64. PSB Rc82 is an ex-ample of a variety that became very popular, and IR64 isone of its grandparents. In India as well, the varietyMTU 1010 became very popular, and it is a cross ofKrishnaveni/ was a dominant variety in Indonesia for over twodecades. In the last 10 years, it has been replaced by thevariety Ciherang, which has very similar grain qualityand improved yields. This variety is from the crossIR18349-53-1-3-1-3/IR19661-131-3-1//IR19661-131-3-1/IR64/IR64, and has high genetic similarity with IR64IRRI 2015; Septiningsih et al. 2014. It has very similargrain quality to IR64 and is also morphologically andgenetically similar Muhamad et al. 2017.The availability of genome-wide molecular markers formarker assisted selection enabled the transfer of import-ant traits into popular varieties like IR64 through marker-assisted backcrossing MABC Collard and Mackill2008. Early examples of this included varieties developedby pyramiding BB resistance genes into IR64, includingAngke and Conde in Indonesia, and NSIC Rc142 in thePhilippines Verdier et al. 2012.The rice submergence tolerance gene SUB1 was intro-duced by marker assisted backcrossing into IR64 andseveral other popular varieties Septiningsih et al. 2009Fig. 4. Because IR64 had moderate tolerance to sub-mergence, IR64-Sub1 tended to perform better undersubmergence than some of the other Sub1 lines, and itsrelatively early maturity allowed it to recover and produceyields after prolonged flooding and before the onset of lowtemperatures Singh et al. 2010; Singh et al. 2013. IR64-Sub1 was released as Submarino 1 in the Philippines in2009. The genetic similarity of Ciherang with IR64 wasexploited to develop a submergence-tolerant version ofCiherang with only one backcross Septiningsih et IR64-Sub1 was also used to develop submergencetolerant varieties in Vietnam Lang et al. 2015.Many interesting genes and QTLs have been backcrossedinto IR64 and these progeny are being evaluated for usefultraits Table 2. One of the most important is drought toler-ance. This trait was introduced by backcrossing fromdrought tolerance donor Aday Sel into IR64 Venuprasadet al. 2011, and some of the derived lines showed yield in-creases of 528 to 1875 kg ha-1 over IR64 under severedrought conditions Swamy et al. 2013. Breeding lines withtwo drought-tolerance QTLs + into IR64 showed improved performance underabFig. 4 aIR64 and IR64-Sub1 under non-flooded conditions at IRRI. bTrials after submergence showing the survival of IR64-Sub1 comparedto IR64. Fields were submerged for 17 days at 28 days after seeding.Photos from IRRIMackill and Khush Rice 2018 1118 Page 6 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. drought stress. These lines had improved hydraulic con-ductivity and higher root length density Henry et al. 2015.The gene DRO1, conferring deeper rooting and droughttolerance, was also transferred into IR64 by backcrossing,and resulted in NILs with higher drought tolerance Uga etal. 2013. According to the authors, a single bp deletion inDRO1 resulted in a stop codon in IR64 and caused shallowrooting and drought intolerance, and this deletion was ob-served in IR64 and some of its progeny but not in itsancestors. The IR64 Dro1-NIL had a 14% higher yieldthan IR64 Deshmukh et al. 2017. IR64-Sub1 is beingused as a recipient for drought tolerance QTLs to de-velop a version of IR64 tolerant of both stresses Singh etal. 2016.IR64 is generally considered a restorer line for hybrid rice,particularly in the WA CMS system widely used in indica“three-line”hybrid breeding Xie et al. 2014. However, Tor-iyama and Kazama 2016 developed a new IR64 cmstermed CW type Chinese wild rice, restored by the IRRI, induced mutation was used to generate alarge collection of mutants in IR64. This collectionhas been used to discover many genes controlling im-portant traits in rice Wu et al. 2005. Some of thesemutants show favorable phenotypes that could beused directly in rice breeding. Examples includetolerance to salinity Nakhoda et al. 2012, resistanceto blast disease Madamba et al. 2009, resistance totungro disease Zenna et al. 2008, and drought toler-ance Cairns et al. 2009.Transgenic applications have been limited for rice andare currently not in commercial cultivation. However,Agrobacterium mediated transformation protocols arewell developed and used for IR64 Ignacimuthu andRaveendar 2011. For example, it has been transformedwith genes conferring higher Fe and Zn content in theendosperm Oliva et al. 2014; Trijatmiko et al. 2016 andherbicide tolerance Chhapekar et al. 2015.ConclusionsThis brief review attempts to document the value ofthe variety IR64 for rice breeding and genetics butcannot contain all the information available. At onetime, this variety was estimated to be grown on 9–10million ha annually Laird and Kate 1999. Consider-ing the many years it has been in production, overapproximately two decades, it has been providinghundreds of millions of consumers with high-qualityrice. In this sense it resembles some of the othermegavarietieslikeSwarnaandSambaMahsuri,grown in India. However, breeders have been quick totake advantage of this variety to make furtherTable 2 Near Isogenic Lines NILs developed in IR64 genetic background with genes conferring novel and improved traitsTrait/QTL Comments ReferencesSubmergence toleranceSUB1The SUB1 major gene was introduced by Marker AssistedBackcrossing MABC into IR64 and released in several countries.Septiningsih et al. 2009Drought toleranceDRO1Breeding line developed by MABC showed improved droughttolerance through deeper root system.Uga et al. 2013Drought tolerance + derived by MABC showed improved yield under severedrought stress.Swamy et al. 2013SPIKE geneNARROW LEAF1NIL with this gene showed 15–36% higher yield when introgressedinto IR64. The gene increases spikelet number.Fujita et al. 2013.Improved agronomic traits 334 introgression lines developed in IR64 background usingtropical japonica donorsFarooq et al. 2010; Fujita et al. 2009;Kato et al. 2010; Tagle et al. 2016Anaerobic germinationAG1IR64-AG1 was developed by introgressing the AG1 QTLinto IR64.Toledo et al. 2015Yield QTL identified fromO. rufipogonSome QTLs from low yielding wild rice O. rufipogon can increaseyield in IR64 background.Cheema et al. 2008; Septiningsihet al. 2003Drought tolerance from population of alien introgression lines using an accession of Africanrice O. glaberrima backcrossed to IR64 BC2, and identified QTLsassociated with drought-related traits.Bimpong et al. 2011Early-morning floweringqEMF3NIL IR64 + qEMF3 with early morning flowering was developed usingthree backcrosses by marker assisted backcrossing and it flowered earlier in the day than IR64. In this case the donor was wild riceO. officinalis. This trait can confer tolerance to high temperature at anthesis.Hirabayashi et al. 2015Tolerance to Pdeficiency Pup1Tolerance of P deficiency was introduced into IR64-Pup1, with the Pup1gene for more efficient P uptake.Chin et al. 2011; Wissuwa et to rice yellowmottle virus RYMVResistance to RYMV was introduced into IR64 background by markerassisted backcrossing.Ahmadi et al. 2001Mackill and Khush Rice 2018 1118 Page 7 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. advances. As an example, IR64 has been replaced inmost of the Philippines and Indonesia by new var-ieties with similar quality attributes but improvedagronomic traits like disease resistance and highergrain breeding is a continual process and all varieties areexpected to be replaced by improved varieties over is still a popular variety in some areas, particularly inIndia where it is a popular variety in the north. Its area isgradually declining, due to release of improved as outlined here, it lives on through its progenythat are cultivated or under evaluation throughout the re-gion. Some of the most important factors that enabled thedevelopment of such a superior variety include a largebreeding program where many crosses were made annu-ally and large segregating populations were grown, well-defined objectives with focus on the most necessary traitsincluding preferred quality attributes, systematic screeningby skilled researchers for required traits, sensory data toconfirm quality of the cooked rice, a suitable evaluationprogram to measure yield as early in the breeding pro-gram as possible, and an effective outreach effort to evalu-ate advanced selections under farmers’conditions andensure that seed was widely development of high-quality mega varieties like IR64has provided a challenge to rice breeders to make furtherimprovements to varieties that are widely-accepted byfarmers. This challenge has been met well in the Philippinesand Indonesia where new varieties have replaced IR64, butless well in India where the variety is still popular. In gen-eral, new varieties that aim to replace the mega varietiesmust offer a clear advantage, such as improved stress toler-ance or higher yield. Additionally, the rice processing in-dustry must be supportive of the efforts to replace existingvarieties with new ones, so that farmers will have a suitablemarket for their crop produced from these new Bacterial blight; BPH Brown Planthopper; CSSL Chromosome segmentsubstitution library; GEU Genetic Evaluation and Utilization; GLH Greenleafhopper; GT Gelatinization temperature; HYV High-yielding variety;IRRI International Rice Research Institute; MABC Marker assistedbackcrossing; RIL Recombinant inbred population; RTBV Rice tungrobacilliform virus; RTSV Rice tungro spherical virus; RVA Rapid visco analyzer;WBPH White backed planthopperAcknowledgmentsNot of data and materialsNot and GSK conceived of the manuscript. DJM served as lead author andwrote most of the manuscript. GSK reviewed the entire manuscript andprovided corrections and additional information. Both authors approved thefinal approval and consent to participateNot for publicationNot interestsThe authors declare that they have no competing Nature remains neutral with regard to jurisdictional claims inpublished maps and institutional details1Mars, Inc. and Department of Plant Sciences, University of California, Davis,CA 95616, of Plant Sciences, University of California, Davis,CA 95616, 2 November 2017 Accepted 14 March 2018ReferencesAdhikari TB, Mew TW, Teng PS 1994 Progress of bacterial blight on rice cultivarscarrying different Xa genes for resistance in the field. Plant Dis 7873–77Ahmadi N, Albar L, Pressoir G, Pinel A, Fargette D, Ghesquiere A 2001 Geneticbasis and mapping of the resistance to Rice yellow mottle virus. III. Analysisof QTL efficiency in introgressed progenies confirmed the hypothesis ofcomplementary epistasis between two resistance QTLs. 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J Phytopathol 154197–203Zhang ZJ, Li M, Fang YW, Liu FC, Lu Y, Meng QC, Jun CC, Yi XH, Gu MH, Yan CJ2012 Diversification of the waxy gene is closely related to variations in riceeating and cooking quality. Plant Mol Biol Rep 30462–469Zhao DL, Atlin GN, Amante M, Cruz MTS, Kumar A 2010 Developing aerobic ricecultivars for water-short irrigated and drought-prone rainfed areas in thetropics. Crop Sci 502268–2276Mackill and Khush Rice 2018 1118 Page 11 of 11Content courtesy of Springer Nature, terms of use apply. Rights reserved. and ConditionsSpringer Nature journal content, brought to you courtesy of Springer Nature Customer Service Center GmbH “Springer Nature”.Springer Nature supports a reasonable amount of sharing of research papers by authors, subscribers and authorised users “Users”, for small-scale personal, non-commercial use provided that all copyright, trade and service marks and other proprietary notices are maintained. 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Springer Naturemay revoke this licence to you at any time and remove access to any copies of the Springer Nature journal content which have been the fullest extent permitted by law, Springer Nature makes no warranties, representations or guarantees to Users, either express or impliedwith respect to the Springer nature journal content and all parties disclaim and waive any implied warranties or warranties imposed by law,including merchantability or fitness for any particular note that these rights do not automatically extend to content, data or other material published by Springer Nature that may be licensedfrom third you would like to use or distribute our Springer Nature journal content to a wider audience or on a regular basis or in any other manner notexpressly permitted by these Terms, please contact Springer Nature atonlineservice ... These results indicate that the Koshihikari allele can be useful to increase panicle number in most indica accessions. To verify this, we developed NILs of Hokuriku 193-MP3 and IR64-MP3 on two highyielding indica cultivars -Hokuriku 193 and IR64released in Japan and the Philippines, respectively Figure S6 Goto et al., 2009;Mackill & Khush, 2018. Both cultivars were categorized as Hap7, like Takanari. ...... We developed another NIL for fc1, the loss-of-function allele of OsTB1/FC1 originated from a natural mutant line, Norin 8-fc1, by repeated backcrossing with Takanari and MAS NIL-fc1 BC 3 F 2 . To examine the effect of MP3 in the different genetic backgrounds, we chose highyielding indica cultivars, Hokuriku 193 Goto et al., 2009 and IR64 Mackill & Khush, 2018 Morales et al., 2020. ...Improving crop yield potential through an enhanced response to rising atmospheric CO2 levels is an effective strategy for sustainable crop production in the face of climate change. Large-sized panicles containing many spikelets per panicle have been a recent ideal plant architecture IPA for high-yield rice breeding. However, few breeding programs have proposed an IPA under the projected climate change. Here, we demonstrate through the cloning of the rice Oryza sativa quantitative trait locus for MORE PANICLES 3 MP3 that the improvement in panicle number increases grain yield at elevated atmospheric CO2 levels. MP3 is a natural allele of OsTB1/FC1, previously reported as a negative regulator of tiller bud outgrowth. The temperate japonica allele advanced the developmental process in axillary buds, moderately promoted tillering, and increased the panicle number without negative effects on the panicle size or culm thickness in a high-yielding indica cultivar with large-sized panicles. The MP3 allele, containing three exonic polymorphisms, was observed in most accessions in the temperate japonica subgroups but was rarely observed in the indica subgroup. No selective sweep at MP3 in either the temperate japonica or indica subgroups suggested that MP3 has not been involved and utilized in artificial selection during domestication or breeding. A free-air CO2 enrichment experiment revealed a clear increase of grain yield associated with the temperate japonica allele at elevated atmospheric CO2 levels. Our findings show that the moderately increased panicle number combined with large-sized panicles using MP3 could be a novel IPA and contribute to an increase in rice production under climate change with rising atmospheric CO2 levels.... In general, new varieties that aim to replace the popular varieties must offer a clear advantage, such as improved stress tolerance or higher yield. Additionally, the rice processing industry must be supportive of the efforts to replace existing varieties with new ones, so that farmers will have a suitable market for their crops produced from these new varieties [6]. ...Ciherang is the most extensively planted rice variety in the Indonesia. Ciherang was released as a rice variety in 2000 and successfully replaced IR 64 as the most dominant variety. The wide adoption of Ciherang is because of its acceptable to farmers’ preferences including high yield, resistance to major diseases and good grain quality. Recently, Ciherang become vulnerable to pest and diseases and get low yield due to more occurrence the abiotic stress. The Rice breeding program to develop the Ciherang reborn has been conducted in Indonesian Center for Rice Research. The research aimed to select lines based on yield, morphological performance, and resistant to main pest and diseases for next evaluation of a multilocation yield trial for releasing variety. The materials used were 56 rice genotypes that evaluated yield, agronomic characters, and evaluated to brown planthopper and bacterial left blight. Ten promising lines was selected, derivative from Ciherang or similar ideotype with Ciherang, high yielding, more resistant to main pest and diseases than Ciherang. These promising lines was evaluated in multilocation yield trials for releasing variety.... Moroberekan, a jap type, is a heat sensitive rice type at the reproductive stage Jagadish et al. 2010. IR64, an ind type, is popular high grain yield rice cultivar Mackill and Khush 2018. These three species showed genotype-specific protein alterations in the anthers under HS Kumar et al. 2023. ...Main conclusion The Hsp101 gene is present across all sequenced rice genomes. However, as against Japonica rice, Hsp101 protein of most indica and aus rice contain insertion of glutamic acid at 907th position. Abstract The understanding of the heat stress response of rice plants is important for worldwide food security. We examined the presence/absence variations PAVs of heat shock proteins Hsps/heat shock transcription factor Hsf genes in cultivated rice accessions. While 53 Hsps/Hsfs genes showed variable extent of PAVs, 194 genes were the core genes present in all the rice accessions. ClpB1/Hsp101 gene, which is critically important for thermotolerance in plants, showed 100% distribution across the rice types. Within the ClpB1 gene sequence, 40 variation sites consisting of nucleotide polymorphisms SNPs and short insertion/deletions InDels were discerned. An InDel in ClpB1 leading to an in-frame insertion of 3 nucleotides TCC thereby an additional amino acid glutamic acid at 907th amino acid position was noted in most of the indica and aus as against japonica rice types. Three rice types namely Moroberekan japonica, IR64 indica and N22 aus were further analyzed to address the question of ClpB1 genomic variations and its protein levels with the heat tolerance phenotype. The growth profiling analysis in the post heat stress HS period showed that N22 seedlings were most tolerant, IR64 moderately tolerant and Moroberekan highly sensitive. Importantly, the ClpB1 protein sequences of these three rice types showed distinct differences in terms of SNPs. As the ClpB1 protein levels accumulated post HS were generally higher in Moroberekan than N22 seedlings in our study, it is proposed that some additional gene loci in conjunction with ClpB1 regulate the overall rice heat stress response.... Interestingly, most of the positive alleles for high GY and early DF were contributed by high yielding IR14M110 and early maturing parents IR950448-B-5-22-19-GBS respectively. High-grain yield and early-maturity are two most desirable traits for rice varietal development Zhao et al., 2011;MacKill and Khush, 2018;Li et al., 2019. Similarly, QTLs for PL and GW were contributed by Kaliboro, while TGW and GL were derived from IR14M141 Table 2. ...Breeding staple crops with increased micronutrient concentration is a sustainable approach to address micronutrient malnutrition. We carried out Multi-Cross QTL analysis and Inclusive Composite Interval Mapping for 11 agronomic, yield and biofortification traits using four connected RILs populations of rice. Overall, MC-156 QTLs were detected for agronomic 115 and biofortification 41 traits, which were higher in number but smaller in effects compared to single population analysis. The MC-QTL analysis was able to detect important QTLs viz qZn , qFe , qGY , qDF , qPH , qNT , qPT , qPL , qTGW , qGL , and qGW , which can be used in rice genomics assisted breeding. A major QTL qZn for grain Zn concentration has been detected on chromosome 5 that accounted for 13% of R ² . In all, 26 QTL clusters were identified on different chromosomes. qPH epistatically interacted with qZn and qGY . Most of QTLs were co-located with functionally related candidate genes indicating the accuracy of QTL mapping. The genomic region of qZn was co-located with putative genes such as OsZIP5 , OsZIP9 , and LOC_OS05G40490 that are involved in Zn uptake. These genes included polymorphic functional SNPs, and their promoter regions were enriched with cis -regulatory elements involved in plant growth and development, and biotic and abiotic stress tolerance. Major effect QTL identified for biofortification and agronomic traits can be utilized in breeding for Zn biofortified rice varieties.... The panicle length means of Ciherang in locations 1, 2, and 3 were and cm, respectively data not shown, showing a relatively consistent performance across environments. This variety was bred from the IR64 variety, which was a mega-variety in Indonesia and other countries in Southeast and South Asia Mackill and Khush, 2018. ...Syaifullah RahimWilly Bayuardi SuwarnoHajrial AswidinnoorOne essential objective of rice breeding is to obtain high-yielding varieties. This study aims to 1 determine the effect of genotype G, environment E, and genotype by environment G×E interaction on agronomic traits and yield of 12 lowland rice genotypes, 2 estimate variance components and repeatability 3 identify promising rice genotypes with good agronomic performance and high yield potential. The trials were conducted in three irrigated lowland locations from June to November 2020, using a randomized complete block design with three replications. The results showed that the G×E interaction effect was significant on days to flowering, days to harvest, plant height, number of tillers, and panicle length. The genotype's main effect was significant on yield. Four IPB lines IPB189-F-13-1-1, IPB189-F-23-2-2, IPB193-F-17-2-3, and IPB193-F-30-2-1 had a higher average yield than Ciherang and Inpari 32 varieties. The IPB189-F-23-2-2 had a panicle length stability across the three test locations and a higher average yield than the checks.... The pathogen, Xanthomonas oryzae pv. oryzae Xoo, secretes transcription-activator-like effectors TALes to recognize effector-binding elements EBEs and induce, at minimum, one of OsSWEET11, OsSWEET13 and OsSWEET14 to increase sugar content in the invasion sites, and simultaneous introduction of mutations in EBE regions of all three OsSWEET promoters using CRISPR/Cas9 in rice line Kitaake and elite mega varieties IR64 Mackill and Khush, 2018 and Ciherang-Sub1 Toledo et al., 2015 confers them robust and broad-spectrum resistance to rice blight Eom et al., 2019;Oliva et al., 2019. The promoter of maize ZmSWEET4c was strongly selected during domestication and the higher gene expression in maize than maize ancestor teosinte leads to larger grains . ...SWEET Sugars Will Eventually be Exported Transporter proteins, an essential class of sugar transporters, are involved in vital biological processes of plant growth and development. To date, systematical analysis of SWEET family in barley Hordeum vulgare has not been reported. In this study, we genome-wide identified 23 HvSWEET genes in barley, which were further clustered into four clades by phylogenetic tree. The members belonging to the same clade showed relatively similar gene structures and conserved protein motifs. Synteny analysis confirmed the tandem and segmental duplications among HvSWEET genes during evolution. Expression profile analysis demonstrated that the patterns of HvSWEET genes varied and the gene neofunctionalization occurred after duplications. Yeast complementary assay and subcellular localization in tobacco leaves suggested that HvSWEET1a and HvSWEET4, highly expressed in seed aleurone and scutellum during germination, respectively, functioned as plasma membrane hexose sugar transporters. Furthermore, genetic variation detection indicated that HvSWEET1a was under artificial selection pressure during barley domestication and improvement. The obtained results facilitate our comprehensive understanding and further functional investigations of barley HvSWEET gene family, and also provide a potential candidate gene for de novo domestication breeding of Arbuscular Mycorrhizal Fungi AMF belong to the Glomeromycota clade and can form root symbioses with 80% of Angiosperms, including agronomically-interesting crops species such as wheat, maize and rice. By increasing nutrient availability, uptake and soil anchoring of plants, AMF can improve plant’s growth and tolerance to abiotic stresses. AMF can also reduce symptoms and pathogen load on infected plants, both locally and systemically, through a phenomenon called Mycorrhiza-Induced Resistance MIR. There is scarce information on rice mycorrhization, despite the high potential of this symbiosis in a context of sustainable water management in rice production systems. Results We studied the symbiotic compatibility global mycorrhization & arbuscules intensity and MIR phenotypes between six rice cultivars from two subspecies indica IR64 & Phka Rumduol; japonica Nipponbare, Kitaake, Azucena & Zhonghua 11 and three AMF genotypes Funneliformis mosseae FR140, Rhizophagus irregularis DAOM197198 & R. intraradices FR121. The impact of mycorrhization on rice growth and defence response to Xanthomonas oryzae pv. oryzae Xoo infection was recorded via both phenotypic indexes and rice marker gene expression studies. All three AMF genotypes colonise the roots of all rice varieties, with clear differences in symbiotic compatibility depending on the combination under study. AMF interaction induced either neutral, beneficial, or negative effects on rice growth, but only neutral to beneficial effects on the extent of Xoo symptoms on leaves. R. irregularis DAOM197198 proved to be the most colonising AMF in terms of global mycorrhization and arbuscule intensities, inducing rice growth and reducing symptoms caused by Xoo in all rice varieties. Transcriptomic analyses by RT-qPCR on leaves of two rice cultivars contrasting in their interactions with AMF, shows two different pattern of response both on growth and defence marker genes, that can be related to their phenotypic responses. Conclusions The symbiotic compatibility between rice and AMF depends both on plant cultivar and AMF genotypes. Under our conditions, it drives beneficial, neutral, or negative effects on rice growth, and in some cases, MIR phenotypes after Xoo leaf infection. The interactions between rice and AMF genotypes drive different transcriptomic responses, shedding light on molecular markers of compatibility at the leaf CGIAR system of international agricultural research centers has made major contributions to crop improvement in developing countries, particular in rice and wheat. This paper brings together an expanded set of evidence on the diffusion and productivity impact of CGIAR crop improvement research through 2020, and breaks out these impacts by crop, region, and over time. By 2016-2020, CGIAR-related crop improvement technologies are estimated to have been adopted on about 221 million hectares across Asia, Africa and Latin America and had generated economic welfare gains of $57 billion annually. These welfare gains were increased in the 2010s at about the same rate as in the 1990s, at about $ billion/year, through technology diffusion to new areas as well as variety turnover in previously affected areas. In the early days of the “Green Revolution,” these welfare impacts were largely confined to rice and wheat in Asia, but in the most recent decades have grown to include a larger range of crops and geographies, notably to Sub-Saharan Africa. Although improved crop varieties have been the main technology through which CGIAR crop centers have achieved these impacts, CGIAR-related integrated pest management and natural resource management technologies have also made significant contributions to crop Kumar Dwivedi Santosh KumarMignon A. NatividadAmelia HenryBackground Harvest index is an important component of grain yield and is typically reduced by reproductive stage drought stress in rice. Multiple drought response mechanisms can affect harvest index including plant water status and the degree of stem carbohydrate mobilization during grain filling. In this study, we aimed to dissect the contributions of plant water status and stem carbohydrate mobilization to harvest index. Pairs of genotypes selected for contrasting harvest index but similar biomass and days to flowering were characterized at ICAR-RCER, Patna, India and at IRRI, Philippines. Results Multiple traits were related with harvest index across experiments, including mobilization efficiency at both sites as indicated by groupings in principal component analysis, and plant water status as indicated by direct correlations. Biomass-related traits were positively correlated with harvest index at IRRI but biomass was negatively correlated with harvest index at ICER-RCER, Patna. We observed that some pairs of genotypes showed differences in harvest index across environments, whereas other showed differences in harvest index only under drought. Of all time points measured when all genotypes were considered together, the stem carbohydrate levels at maturity were most consistently negatively correlated with harvest index under drought, but not under well-watered conditions. However, in the pairs of genotypes grouped as those whose differences in harvest index were stable across environments, improved plant water status resulted in a greater ability to both accumulate and remobilize stored carbohydrate, starch. Conclusion By distinguishing between genotypes whose harvest index was improved across conditions as opposed to specifically under drought, we can attribute the mechanisms behind the stable high-harvest index genotypes to be more related to stem carbohydrate remobilization than to plant water status. The stable high-harvest index lines in this study Aus 257 and Wanni Dahanala may confer mechanisms to improve harvest index that are independent of drought response and therefore may be useful for breeding improved rice Gita Lestari Mohammad UbaidillahRed rice contains high anthocyanin and bioactive antioxidant compounds that prevent free radical reactions. Cempo Salamet has potential as an antioxidant source, and the characteristics are red colored grains, 4-5 months old, 169 cm plant height, 7 productive tillers per plant, and resistance to blast disease. IR64 had been developed with the following characteristics 3 months old, 85 cm plant height, 20-35 productive tillers per plant, resistance to brown leafhoppers pigment. This study aimed to obtain information on the segregation of the F3 population from crosses between the Cempo Salamet and IR64 varieties. Research methods included preparation and maintenance with genotype analysis. PCR analysis was conducted using SSR markers with primer RM346, RM316, RM228, and RM339. The segregation in F3 plants was 50% for >130 cm plant height, 51% for 10-19 tillers per plant, 67% for g/100-grain weight, and 33% strong red for colour intensity. The findings demonstrated that SSR markers RM346, RM339, and RM228 could validate Cempo Salamet, IR64, and F3 DNA bands. However, RM316 could not validate all DNA bands in the research sample. ABSTRAK Beras merah mengandung antosianin yang tinggi dan senyawa bioaktif antioksidan yang mampu mencegah terjadinya reaksi radikal bebas. Cempo Salamet berpotensi sebagai sumber antioksidan yang memiliki karakteristik biji berwarna merah, umur 4-5 bulan, tinggi tanaman 169 cm, anakan produktif 7 batang, tahan terhadap penyakit blas. IR64 telah banyak dibudidayakan dengan karakteristik umur 3 bulan, tinggi tanaman 85 cm, anakan produktif 20-35 batang, tahan terhadap wereng coklat, akan tetapi tidak mengandung pigmen. Penelitian ini bertujuan mendapatkan informasi segregasi populasi F3 hasil persilangan antara varietas Cempo Salamet dan IR64. Metode penelitian meliputi persiapan dan pemeliharaan tanaman serta analisis genotipe bioaktif. Analisis PCR menggunaan marka SSR dengan primer RM 346, RM 316, RM 228, dan RM 339. Terjadi segregasi karakter morfologi pada populasi F3 yaitu diperoleh tanaman dengan tinggi >130 cm 50%, 10-19 anakan 51%, bobot 100 bulir dengan 2,2 g 67%, dan intensitas warna bulir dengan merah kuat 33%. Penelitian menunjukkan marker SSR yang dapat memvalidasi pita-pita DNA yaitu RM346, RM339, and RM228, sedangkan RM316 tidak dapat memvalidasi keseluruhan pita-pita DNA pada sampel Heat stress is one of the major abiotic threats to rice production, next to drought and salinity stress. Incidence of heat stress at reproductive phase of the crop results in abnormal pollination leading to floret sterility, low seed set and poor grain quality. Identification of QTLs and causal genes for heat stress tolerance at flowering will facilitate breeding for improved heat tolerance in rice. In the present study, we used 272 F8 recombinant inbred lines derived from a cross between Nagina22, a well-known heat tolerant Aus cultivar and IR64, a heat sensitive popular Indica rice variety to map the QTLs for heat tolerance. Results To enable precise phenotyping for heat stress tolerance, we used a controlled phenotyping facility available at ICAR-Indian Institute of Wheat and Barley Research, Karnal, India. Based on 'days to 50% flowering' data of the RILs, we followed staggered sowing to synchronize flowering to impose heat stress at uniform stage. Using the Illumina infinium 5K SNP array for genotyping the parents and the RILs, and stress susceptibility and stress tolerance indices SSI and STI of percent spikelet sterility and yield per plant g, we identified five QTLs on chromosomes 3, 5, 9 and 12. The identified QTLs explained phenotypic variation in the range of to 21. 29%. Of these five QTLs, two high effect QTLs, one novel and one known were mapped in less than 400 Kbp genomic regions, comprising of 65 and 54 genes, respectively. Conclusions The present study identified two major QTLs for heat tolerance in rice in narrow physical intervals, which can be employed for crop improvement by marker assisted selection MAS after development of suitable scorable markers for breeding of high yielding heat tolerant rice varieties. This is the first report of a major QTL for heat tolerance on chromosome 9 of rice. Further, a known QTL for heat tolerance on chromosome 5 was narrowed down from 23 Mb to 331 Kbp in this near-isogenic lines NILs of Oryza sativa subsp. indica cv. IR64 Dro1-NIL, Sta1-NIL, Dro1+Sta1-NIL with DEEPER ROOTING 1 DRO1, a novel gene for steeper root growth angle, and/or with Stele Transversal Area 1 Sta1, a QTL for wider stele area, were tested under flooded lowland FL, alternate wetting and drying lowland AWD, and rainfed upland UP conditions in 2013 and 2014 to compare the effects of DRO1 and Sta1 on yield across different water management regimes. Genotypic variation and water management effects were significant for grain yield, aboveground biomass, and harvest index, as well as their interactions with year, but no significant genotype × water interaction was detected. Dro1-NIL had 14% higher yield than that of IR64 across the three water conditions due to higher harvest index, aboveground biomass, leaf area index, and number of grains. Sta1 tended to reduce the carbon isotope composition δ¹³C, leading to a higher harvest index of Sta1-NIL than that of IR64, but grain yield was not increased. Dro1+Sta1-NIL had the highest fraction of intercepted radiation, cumulative radiation interception, and panicle number, with a small but insignificant yield improvement over IR64, but the combination of DRO1 and Sta1 did not surpass the increment from the effects of DRO1 alone. AWD in the more rainy year 2014 attained both higher water productivity and higher biomass, with significant water by year interaction for water productivity. Genotypic variation in water productivity was related with higher leaf area index and fraction interception, with Dro1-NIL larger than in IR64 and Hu Jianbo CaoJie ZhangShiping WangThe major disease resistance gene Xa4 confers race-specific durable resistance against Xanthomonas oryzae pv. oryzae, which causes the most damaging bacterial disease in rice worldwide. Although Xa4 has been one of the most widely exploited resistance genes in rice production worldwide, its molecular nature remains unknown. Here we show that Xa4, encoding a cell wall-associated kinase, improves multiple traits of agronomic importance without compromising grain yield by strengthening the cell wall via promoting cellulose synthesis and suppressing cell wall loosening. Strengthening of the cell wall by Xa4 enhances resistance to bacterial infection, and also increases mechanical strength of the culm with slightly reduced plant height, which may improve lodging resistance of the rice plant. The simultaneous improvement of multiple agronomic traits conferred by Xa4 may account for its widespread and lasting utilization in rice breeding programmes Low phosphorus availability is a major factor limiting rice productivity. Since root traits determine phosphorus acquisition efficiency, they are logical selection targets for breeding rice with higher productivity in low phosphorus soils. Before using these traits for breeding, it is necessary to identify genetic variation and to assess the plasticity of each trait in response to the environment. In this study, we measured phenotypic variation and effect of phosphorus deficiency on root architectural, morphological and anatomical traits in 15 rice Oryza sativa genotypes. Rice plants were grown with diffusion-limited phosphorus using solid-phase buffered phosphorus to mimic realistic phosphorus availability conditions. Results Shoot dry weight, tiller number, plant height, number of nodal roots and shoot phosphorus content were reduced under low phosphorus availability. Phosphorus deficiency significantly reduced large lateral root density and small and large lateral root length in all genotypes, though the degree of plasticity and relative allocation of root length between the two root classes varied among genotypes. Root hair length and density increased in all genotypes in response to low phosphorus. Nodal root cross-sectional area was significantly less under low phosphorus availability, and reduced cortical area was disproportionately responsible for this decline. Phosphorus deficiency caused a 20 % increase in the percent cortical area converted to aerenchyma. Total stele area and meta-xylem vessel area responses to low phosphorus differed significantly among genotypes. Phosphorus treatment did not significantly affect theoretical water conductance overall, but increased or reduced it in a few genotypes. All genotypes had restricted water conductance at the base of the nodal root compared to other positions along the root axis. Conclusions There was substantial genetic variation for all root traits investigated. Low phosphorus availability significantly affected most traits, often to an extent that varied with the genotype. With the exception of stele and meta-xylem vessel area, root responses to low phosphorus were in the same direction for all genotypes tested. Therefore, phenotypic evaluations conducted with adequate fertility should be useful for genetic mapping studies and identifying potential sources of trait variation, but these should be confirmed in low-phosphorus Peng M. R. C. LazaRomeo M. VisperasGurdev S KhushGenetic improvement in grain yield has been intensively studied in wheat Triticum aestivum L., barley Hordeum vulgare L., oat Avena sativa L., maize Zea mays L., and soybean [Glycine max L. Merr.]. Such information is limited in rice Oryza sativa L.. The objective of this study was to determine the trend in the yield of rice cultivars-lines developed since 1966. Twelve cultivars-lines were grown at the International Rice Research Institute IRRI farm and the Philippine Rice Research Institute farm during the dry season of 1996. Seven cultivars-lines were grown at IRRI farm in the dry season of 1998. Growth analyses were performed at key growth stages, and yield and yield components were determined at physiological maturity. Regression analysis of yield versus year of release indicated an annual gain in rice yield of 75 to 81 kg ha-1, equivalent to 1% per year. The highest yields obtained with the most recently released cultivars was 9 to 10 Mg ha-1, which is equivalent to reported yields of IR8 and other early IRRI cultivars obtained in the late 1960s and early 1970s at these same sites. Therefore, the 1% annual increase in yield may not represent genetic gain in yield potential. The increasing trend in yield of cultivars released before 1980 was mainly due to the improvement in harvest index HI, while an increase in total biomass was associated with yield trends for cultivars-lines developed after 1980. Results suggest that further increases in rice yield potential will likely occur through increasing biomass production rather than increasing of rice varieties tolerant to submergence, high-yielding and good quality is essential due to increased flooding in the lowland areas in the Mekong delta, Vietnam. The purpose of this experiment was to develop rice varieties tolerant to submergence on the basis of a combination of two breeding methods by molecular markers, single cross and backcross. Evaluating tolerance of F8 and BC2F4 generation on the basis in the field of flooded and unflooded conditions to select promising lines to meet for farmers applying into production. The Sub1 gene was introgressed into the new breeding lines. Some high yielding and good submergence tolerant lines were developed BC2F4-4-3 however, also many lines failed were not acceptable due to their long duration between 120-130 days or their high rate of unfilled grain. This is a opportunity to improve good rice varieties for condition of breeding submergence rice varieties in Vietnam. © Society for the Advancement of Breeding Research in Asia and Oceania SABRAO S KhushIn the 1960s there were large-scale concerns about the world's ability to feed itself. However, widespread adoption of "green revolution" technology led to major increases in food-grain production. Between 1966 and 1990, the population of the densely populated low-income countries grew by 80%, but food production more than doubled. The technological advance that led to the dramatic achievements in world food production over the last 30 years was the development of high-yielding varieties of wheat and rice. These varieties are responsive to fertilizer inputs, are lodging resistant, and their yield potential is 2-3 times that of varieties available prior to the green revolution. In addition, these varieties have multiple resistance to diseases and insects and thus have yield stability. The development of irrigation facilities, the availability of inorganic fertilizers, and benign government policies have all facilitated the adoption of green-revolution technology. In the 1990s, the rate of growth in food-grain production has been lower than the rate of growth in population. If this trend is not reversed, serious food shortages will occur in the next century. To meet the challenge of feeding 8 billion people by 2020, we have to prepare now and develop the technology for raising farm productivity. We have to develop cereal cultivars with higher yield potential and greater yield stability. We must also develop strategies for integrated nutrient management, integrated pest management, and efficient utilization of water and soil S KhushWR CoffmanThe Genetic Evaluation and Utilization GEU program of the International Rice Research Institute IRRI is an interdisciplinary program for the improvement of rice crops. Scientists trained in diverse disciplines such as plant breeding, plant pathology, entomology, agronomy, cereal chemistry, plant physiology, and soil chemistry work together and contribute their specialized skills to this joint endeavor. The program has five interrelated components 1 germ plasm collection and conservation, 2 research in disciplinary areas, 3 development of improved germ plasm, 4 distribution, evaluation and exchange of germ plasm internationally, 5 training of young forty thousand rice varieties from different countries are being maintained in the IRRI germ plasm bank. These varieties have been screened for grain quality, resistance to various diseases and insects, and tolerance to various environmental stresses such as drought, high and low temperatures and problem soils. Donor parents for resistances to each of the problem areas have been identified. These parents were utilized for developing improved germ plasm. Varieties with resistance to as many as five diseases and five insect species have been developed. These multiple resistant varieties are grown on millions of hectares of rice land. Seeds of improved breeding materials are exchanged internationally and 194 scientists from different countries have been trained in rice improvement work. Di Indonesia yang sebagian besar masyarakatnya berprofesi sebagai petani ternyata menjadikan negara tersebut sebagai negara agraris. Indonesia banyak menghasilkan petani-petani handal dan tidak kalah dengan petani dari negara lain. Hasil pertanian sangat melimpah di Indonesia, mulai dari rempah-rempah, sayur-mayur dan buah-buahan, ubi, kentang, kopi, cokelat, padi, buah-buahan, dan lain sebagainya. Semua komoditi yang dihasilkan dari pertanian Indonesia tersebut ternyata tidak hanya dikonsumsi oleh masyarakat di dalam negeri, akan tetapi hasil panen adakalanya di ekspor ke luar negeri. Tak heran jika hasil ekspor juga menyumbang terhadap Anggaran Pendapatan Belanja Negara APBN tiap tahunnya. Intensifikasi Pertanian Untuk meningkatkan hasil pertanian sehingga dapat menghasilkan produk panen yang berkualitas tinggi, maka pemerintah dan banyak para petani di Indonesia mencari terobosan terbaru untuk memperoleh hasil panen yang optimal yakni dengan membuat sistem pertanian melalui teknik intensifikasi pertanian, diversifikasi pertanian, maupun ekstensifikasi pertanian. Ketiga upaya peningkatan produksi panen tersebut sudah dilakukan sejak tahun 1950 yang dilatarbelakangi oleh ketertarikan pemerintah untuk mengkonversi lahan tanaman tebu menjadi lahan tanaman padi. Rata-rata hasil produksi padi di Indonesia pada tahun 1956-1960 yakni berkisar 2 ton per hektar Jatileksono, 1987. Selanjutnya pada tahun 1960 dan seterusnya swasembada pangan beras menjadi program utama pemerintah Indonesia. Sehingga pada waktu itu, pemerintah Indonesia berupaya semaksimal mungkin untuk meningkatkan produksi pada guna memenuhi kebutuhan di dalam negeri akibat lonjakkan jumlah penduduk Indonesia yang semakin meningkat tajam. A. Intensifikasi Pertanian Intensifikasi pertanian merupakan usaha yang dilakukan petani untuk meningkatkan hasil pertanian dengan cara mengoptimalkan lahan pertanian yang sudah tersedia. Intensifikasi dianjurkan untuk menghasilkan produk pertanian yang tahan penyakit, menghasilkan buah,sayur dan makanan pokok yang berkualitas tinggi dan unggul. Dalam pelaksanaan intensifikasi pertanian adakalanya para petani memperhatikan masalah pengelolaan tanah, pengadaan bibit unggul, penanaman, pemupukkan, pemberantasan hama serta penyakit pada tanaman, pemanenan dan kegiatan selama pasca panen. Program Intensifikasi pertanian di Indonesia dilatarbelakangi oleh keinginan pemerintah dan rakyat untuk memperoleh hasil panen yang layak, cukup untuk memenuhi kebutuhan di dalam negeri, serta mampu untuk program intensifikasi pertanian diharapkan mampu untuk mengurangi dan mengendalikan hama tanaman yang sangat merugikan bagi petani, terutama hama jenis wereng, kutu busuk, kutu buah, ulat daun, serta tikus yang merupakan hewan pengerat dan sering menurunkan produksi tanaman padi. Program intensifikasi pertanian terutama untuk meningkatkan produksi padi dibentuk sejak tahun 1960 melalui program BIMAS Bimbingan Massal. Dalam proses perkembangannya, ternyata masyarakat Indonesia sangat dikeluhkan dengan adanya program intensifikasi pertanian terutama untuk padi. Sebab, para petani dirugikan dengan adanya berbagai hama pengganggu tanaman sehingga pada tahun 1961, 1962 hingga 1969 produksi padi para petani Indonesia banyak yang mengalami serangan hama, serta tak heran jika banyak yang gagal panen. Akibat peristiwa tersebut, pemerintah mulai berupaya untuk mencarikan solusi atas permasalahan tersebut, sehingga pada tahun 1970 hingga 1980, pemerintah membuka ruang kepada rakyat untuk mengatasi masalah hama pada tanaman padi yakni dengan menggunakan berbagai jenis dan formulasi pestisida dengan beranekaragam bahan aktifnya. Pada saat itu, penggunaan pestisida dilakukan untuk memberantas hama penggangu tanaman, namun bukan untuk mencegah atau mengendalikan agar hama tanaman tidak timbul kembali dan merusak tanaman. Pada tahun 1970, 1971, hingga 1979, penggunan pestisida di kalangan petani sangat meningkat tajam, sehingga pada saat itupula produksi bahan makanan, seperti hasil pertanian kentang, ubi, padi, dan berbagai macam buah lainnya mencapai 34%, dan penggunaan pestisida pada saat itu terbukti mampu mematikan hama tanaman. Namun, dengan penggunaan pestisida yang berlebihan di kalangan para petani Indonesia ternyata memberikan efek sangat buruk bagi lingkungan dan manusia itu sendiri. Sehingga pada tahun 1990 ke atas, penggunaan pestisida mulai dikurangi bahkan dilarang dengan alasan bahwa pestisida mampu mempercepat laju pencemaran udara dan pencemaran tanah, menimbulkan berbagai penyakit yang diderita oleh manusi jika terpapar oleh senyawa pestisida terutama bagi para petani maka akibatnya adalah kulit mengalami iritasi, mata merah dan berair, keracunan makanan akibat senyawa pestisida yang bercampur. Dan efek buruk lainnya dari penggunaan pestisida yakni dapat meracuni buah dan sayur. Jika pestisida masuk dan terakumulasi di dalam daging buah dan dikonsumsi manusia, maka kemungkinan besar yang mengonsumsi makanan yang tercemar pestisida tersebut akan mengalami penyakit kanker, jika pada laki-laki menyebabkan prilakunya menjadi kewanita-wanitaan, dan lain sebagainya. Ada beberapa langkah penting untuk melaksanakan intensifikasi pertanian secara menyeluruh yakni dengan program “Panca Usaha Tani” atau “Lima Usaha Tani“. Panca usaha tani ini berkembang pesat pada era pemerintahan presiden Soeharto yang merupakan bagian dari REPELITA pembangunan pertanian sangat digalakkan pada saat itu. Berikut ini panca usaha tani yang dapat dilakukan diantaranya 1. Pemilihan dan Penggunaan Bibit Unggul Sebelum memanfaatkan lahan pertanian secara baik, maka para petani sebaiknya menggunakan bibit unggul baik yang dihasilkan dari hasil panen bibit sebelumnya atau ketika dibeli di pasaran. Bibit unggul menjadi kunci penting untuk menghasilkan tanaman yang berkualitas, tanaman subur, sehat, tinggi, berbuah bagus, akarnya kokoh, serta tahan terhadap berbagai macam serangan hama dan penyakit. Bibit unggul yakni jenis bibit yang disiapkan dan memiliki keunggulan dibandingkan varietas lainnya seperti bibit yang tahan terhadap penyakit dan jamur, bibit yang memiliki produktivitas tinggi, daya vigor tinggi, peka terhadap rangsangan pupuk, fase juvenile yang singkat, serta mempunyai keberanekaragaman bentuk, ukuran, dan warna. Contoh bibit unggul seperti pada padi IR 64, PB 4, pada bibit padi rajalele, dan jagung tongkol untuk produksi bahan makanan pokok. 2. Pengelolaan Lahan dan Tanah Pertanian Secara Tepat dan Terencana Setelah memperoleh bibit unggul, langkah selanjutnya yakni mengelola tanah untuk dipakai dalam penyemaian bibit dan media tumbuh kembang bibit hingga proses pemanenan. Untuk mengelola lahan pertanian dapat ditempuh melalui cara modern dan konvensional tradisional/manual. Cara modern dapat ditempuh dengan menggunakan cara mekanik yakni menggunakan traktor yang sudah modern, sedangkan cara manual/konvensional dapat dilakukan dengan menggunakan alat seperti cangkul. Metode tradisonal menggunakan cangkul memiliki kelemahan yakni sangat tidak efisien dan membutuhkan waktu cukup lama untuk menggarap lahan pertanian. 3. Pengaturan Irigasi atau Saluran Air Pengaturan pasokan air yang dialirkan ke lahan-lahan pertanian sangat penting untuk membuat struktur dan komponen tanah menjadi lembab dan berair sehingga akan memberikan nutrisi dan menjaga tanaman agar tetap sehat, tidak layu, dan kelangsungan hidupnya terjaga dengan baik. Sebaiknya gunakan air secukupnya dan berdasarkan kebutuhan untuk dialiri di lahan pertanian. Umumnya pemberian air tidak boleh melebih titik layu lahan. Dan pasokan air yang cukup di atas lahan sangat penting untuk kelangsungan pertumbuhan dan perkembangan tanaman, serta meningkatkan produktivitas panen nantinya. 4. Pemberian Pupuk Pada Dosis Yang Tepat Tanpa pemberian pupuk buatan, sebenarnya tanah sendiri sudah memiliki unsur hara esensial bagi tanaman. Pemberian pupuk tambahan dilakukan dengan melihat usia tanaman serta menempatkan pupuk pada jarak tertentu. Terkadang para petani jika memberikan pupuk terlalu dekat dengan akar tanaman, maka tak menutup kemungkinan tanaman tersebut akan layu dan berujung pada kematian tanaman, oleh karena itu memberi jarak yang cukup saat pemupukan tanaman sangat penting. Pemberian pupuk pada tanaman dapat dengan menggunakan pupuk dari kotoran hewan ternak, seperti pupuk kandang yang memiliki komposisi dari feses kambing,ayam,unta,sapi dan lainnya. Pupuk kompos dan NPK buatan yang berasal dari sisa-sisa dedaunan juga penting sebagai tambahan nutrisi bagi tumbuhan. Pemberian pupuk perlu melihat usia tanaman yang akan diberi pupuk, dosis, serta cara dan jenis pupuk yang hendak ditambahkan pada tumbuhan. Sehingga jika pemberian pupuk tidak tepat akan berefek pada pertumbuhan dan perkembangan tanaman. 5. Pemberantasan Organisme Penggangu Tanaman Pemberantasan organisme pengganggu tanaman bertujuan sebagai pemeliharaan tanaman. Sebab, masalah yang umum dihadapi oleh para petani yakni hama dan penyakit pada tanaman. Hama tanaman yang sangat mengganggu terutama ulat dan wereng yang merusak struktur daun, serta gulma yang menggangu pada taanaman untuk tumbuh dan berkembang. Terkadang penggunaan pestisida kimia tidak semata-mata untuk memberantas hama, dapat juga menggunakan pestisida alami, misalnya dengan menggunakan predator alami misalnya Ular untuk memutus mata rantai perkembangan tikus di sawah agar produktivitas panen padi meningkat, sehingga keseimbangan eksositem terus terjaga dengan baik. Adanya intensifikasi pertanian tentunya memiliki dampak nyata di dunia pertanian. Tentunya intensifikasi pertanian memiliki dampak positif dan dampak negatif. Dampak positif dengan adanya intensifikasi pertanian yakni produksi panen menjadi meningkat akibat pemilihan benih bibit yang berkualitas, ekosistem di lahan pertanian menjadi stabil, hasil panen rata-rata meningkat seperti yang pernah terjadi 1960-1970 sehingga produksi makanan pernah meningkat hingga 34% dan mampu memenuhi kebutuhan pangan nasional. Sementara itu dampak negatif dari adanya intensifikasi pertanian seperti; 1 Dampak pengelolaan tanah yang kurang diperhatikan dapat merusak struktur tanah dan ekosistem di dalamnya dan ini banyak terjadi pada saat penggunaan alat berat seperti traktor. 2 Dampak buruk pemupukan secara terus-menerus dan tidak terkendali secara baik dapat menyebabkan tanah menjadi asam sehingga pH tanah menjadi menurun, sehingga hasil pertanian tidak produktif. Termasuk unsur hara Nitrogen yang terkandung di dalam pupuk dapat menyebabkan terbentuknya larutan nitrit di dalam tanah yang dapat meresap di sumur warga sekitar daerah pertanian. 3 Dampak dari penggunaan pestisida berlebih dapat menyebabkan dapat menyebabkan mudah berkembangnya hama dan gulma menjadi resisten kebal terhadap senyawa obat/pestisida, terjadinya resurgensi hama timbul kembali, terjadinya ledakan populasi hama terutama yang umum adalah hama ulat dan wereng, keracuanan serta iritasi kulit pada manusia, terjadinya pencemaran udara, air, dan tanah, serta berefek buruk bagi daging buah/sayur yang terpapar senyawa kimia pestisida dapat meracuni hasil panen;buah,sayur,dan sebagainya. B. Ekstensifikasi Pertanian Ekstensifikasi pertanian yaitu perluasan areal pertanian ke wilayah yang sebelumnya belum pernah dimanfaatkan manusia. Program ekstensifikasi pertanian memiliki sasaran terhadap lahan-lahan seperti lahan hutan, padang rumput steppe, lahan gambut pada rawa-rawa, serta bentuk-bentuk lain pada tanah marginal lahan terpinggirkan. Dalam peristilahan internasional dikenal dengan “agricultural land expansion”. Ekstensifikasi pertanian bertujuan untuk mengatasi masalah kurangnya lahan produktif pertanian, perluasan lahan dilakukan dengan mencari lahan-lahan baru yang bisa ditanami tanaman dan menghasilkan nilai tambah dari hasil panen untuk memenuhi kehidupan masyarakat. Ekstensifikasi pertanian biasanya dilakukan di wilayah-wilayah Indonesia seperti Irian Jaya, Kalimantan, Sumatera, dan Sulawesi. Ekstensifikasi pertanian dapat dilakukan oleh petani itu sendiri atau melalui perantara pemerintah sebagai pusat penyelenggara. Namun, biasanya ekstensifikasi pertanian ini dilakukan sendiri oleh petani, berkesinambungan, dan adanya pengawasan dari pemerintah setempat. Berikut ini macam-macam dari ekstensifikasi pertanian yang masih terus diterapkan pada pertanian Indonesia. 1. Perluasan Lahan Pertanian dengan Pembukaan Hutan Baru Sistem pertanian nomaden berpindah-pindah lahan pertanian sudah sering dilihat pada para petani Indonesia. Sistem pertanian nomaden sudah dilakukan oleh petani Indonesia sejak dulu. Cara pertanian nomaden dilakukan secara serentak terhadap lahan tertentu, atau sendiri-sendiri yakni dengan cara membakar tumbuhan di sekitar lahan, kemudian tanahnya digarap dan atau dicangkul kemudian ditanami berbagai jenis sayur mayur, tanaman buah, tanaman obat dan jenis lainnya. Keuntungan dari pembukaan lahan hutan untuk lahan pertanian yakni tingkat kesuburan lahan masih tinggi akibat banyaknya dedaunan yang menyusun komposisi tanah di dalamnya. 2. Perluasan Lahan Pertanian dengan Pembukaan Lahan Kering Perluasan lahan pertanian dengan pembukaan lahan kering dapat dilakukan dengan penangan khusus. Lahan kering maksudnya yaitu lahan atau tanahnya kering, tandus, atau tanahnya kurang subur akibat sedikitnya kandung unsur hara. Dalam pemanfaatannya, lahan kering dapat dimanfaatkan dengan penambahan jenis tanaman yang dapat meningkatkan kesuburan tanah di lokasi itu yakni dengan menanam berbagai tumbuhan seperti kacang-kacangan, pohon lamtoro, dan dapat menambah nutrisi dalam tanah berupa tambahan air, pupuk. 3. Perluasan Lahan Pertanian dengan Pembukaan Lahan Gambut pada Tanah Rawa Lahan gambut umumnya tersebar di wilayah atau daerah rawa-rawa. Di tanah gambut, sangat potensial jika ditanami jenis tumbuhan tertentu sehingga dapat meningkatkan produksi panen. Di tanah gambut beberapa jenis tanaman yang dapat ditanam yakni kangkung, genjer, tanaman pakis, dan padi. Di Indonesia yang memiliki lahan gambut/berawa banyak terdapat di Kalimantan dan Sumatera. Adanya ekstensifikasi pertanian tentunya memberikan dampak positif dan dampak negatif. Salah satu dampak postifinya yakni lahan yang kering,gersang,tandus dapat dioptimalkan kembali fungsinya sehingga dapat ditanami berbagai jenis tanaman yang dapat meningatkan produktivitas panen untuk memenuhi kebutuhan hidup masyarakat. Sementara itu untuk dampak negatif diantaranya; 1. Terjadinya kerusakan ekosistem pada lahan-lahan tertentu. Dapat kita lihat misalnya pada lahan hutan yang sebenarnya hutan itu sendiri memiliki banyak flora dan fauna yang ada di dalamnya. Jika hutan dihabisi, pohon-pohonnya ditebang atau dibakar, maka kemungkinan besar hewan-hewan yang tinggal di ranting-ranting pohon dan sekitaran hutan tersebut akan kehilangan habitat asli mereka, sehingga kepunahan jenis di hutan tersebut kemungkinan besar akan terjadi. 2. Berkurangnya habitat alami hewan di alam. Hal ini dapat kita lihat pada saat penebangan pohon, pembakaran hutan, dan pembangunan gedung-gedung, sehingga hewan-hewan asli penghuni habitat di wilayah tersebut akan kehilangan tempat tinggal, serta aktivitas kesehariannya pun mulai terganggu dan rusak. 3 Terjadinya pemanasan global Global Warming karena aktivitas pembakaran dan penyempitan hutan dan pepohonan yang semakin sulit ditemui. C. Diversifikasi Pertanian Diversifikasi pertanian yakni pemanfaatan lahan pertanian untuk dua kepentingan yang memiliki daya guna sekaligus. Hal ini bertujuan untuk menghindari ketergantungan dari satu hasil pertanian, artinya petani dapat menggunakan satu lahan untuk dua kepentingan bisnis misalnya dapat ditempuh dengan berbagai cara seperti; 1 Memperbanyak jenis kegiatan pertanian; Contohnya selain petani menanam jagung, juga petani tersebut berternak itik dan maupun berternak ikan, membuka tambak. 2 Memperbanyak jenis tanaman pada suatu lahan tertentu; Contohnya Dalam sebuah ladang, selain ditanami singkong, juga ditanamai padi ladang, atau juga ditanamai jagung, tanaman palawija, kacang tanah, sayur-mayur, ubi jalar, dan lain sebagainya. Diversifikasi pertanian sangat penting dilakukan oleh para petani untuk menghasilkan produksi panen yang banyak dan beragam dari hanya memiliki satu lahan saja. Dari kegiatan Diversifikasi pertanian tentu petani banyak diuntungkan karena selain mendapatkan hasil panen beragam, juga kesejahteraan hidup penghasilan berupa uang akan semakin banyak sehingga dapat mengurangi tingkat kemiskinan di kalangan masyarakat berpenghasilan rendah. Selain itu, kegiatan diversifikasi pertanian dapat menambah pengalaman masyarakat petani untuk dapat mengelola lahan dengan berbagai teknik, serta pengetahuan untuk memberi nilai jual dan peluang menghasilkan banyaknya upah pertanian semakin meningkat. Diversifikasi pertanian terbukti mampu memberikan sumbangsih terhadap kesadaran kepada masyarakat untuk bertani. Sebab pekerjaan seperti mencangkul, menanam buah dan sayur mayur tidak hanya ditugaskan kepada petani semata. Seorang guru, siswa, pekerja kantor, dan apapun jenis profesi dapat melakukan program diversifikasi pertanian, contohnya yaitu menanam berbagai jenis tanaman obat, sayur, bunga, dan sebagainya di lahan yang terdapat di halaman rumah, dan lingkungan sekolah. Hal ini penting untuk melatih manusia untuk memiliki jiwa tani. What difference can a “mega variety” make? When it comes to rice, the mega variety IR64 – developed by CGIAR researchers at the International Rice Research Institute IRRI – was widely cultivated in over 10 million hectares within two decades of its release, making a difference in millions of lives worldwide. IR64 was first released in the Philippines in 1985, soon followed by releases in Bhutan, Burkina Faso as FKR42, Cambodia, China, Ecuador as NIAP11, The Gambia, India, Indonesia, Mauritania, Mozambique, Vietnam and Sahelian regions of West Africa. Since its introduction, the strain has contributed greatly to farmer incomes through higher yields and improved grain quality, which has in turn resulted in higher prices and earlier maturity, allowing for higher cropping intensity. IR64 was widely cultivated in over 10 million hectares within two decades of its release, making a difference in millions of lives worldwide Due to its multiple characteristics desired by farmers and consumers, its rapid spread and its wide cultivation, IR64 became known as a “mega variety”. In the field, IR64 is known for its high yield, early maturity and disease resistance. Other qualities that helped IR64 stand out was that it had one of the highest levels of head rice recovery at milling, and was one of the first varieties with multi-pest and disease tolerances to blast and bacterial blight diseases and brown planthopper infestation, which can kill plants or transmit the incurable rice ragged stunt and rice grassy diseases. IR64 was the first variety to have a desirable combination of intermediate amylose content, soft gel consistency, intermediate gelatinization temperature, translucent, and long slender grains. For consumers this translates to an excellent cooking quality, even becoming a quality standard in many countries where it is cultivated. In addition to being a quality standalone variety that is now cultivated in most rice-growing countries, IR64 has also served as a parent in thousands of crosses over the years, and in marker-assisted backcross breeding and various marker studies, making its impact for food security even greater. Header photo A farmer separating full grains from empty grains with nothing but gravity and a gentle breeze in Victoria, Laguna, Philippines. Photo by IRRI.

ir 64 merupakan contoh bibit unggul