优质高产香型杂交稻新组合香优63

Xiangyou 63 was developed at HHRRC using aromatic cytoplasmic male sterile line Xiangxiang 2A and non-aromatic restorer line Minghui 63. It was released to farmers in Jan 1995. Xiangyou 63 is the first quasi-aromatic hybrid rice in China, and Xiangxiang 2A, developed from the cross V20A∥V20B/MR365 by HHRRC, is the first aromatic CMS line in China. The hybrid has so far been planted on more than 20 000 hm2 and seems popular with farmers and consumers. In addition to being aromatic, the hybrid has good grain quality, high-yielding ability, good disease resistance, and wide adaptability.     

Status and Prospects of Hybrid Rice Breeding in Jiangsu, China

HISTORY OF HYBRID RICE DEVELOPMENT China is the first country to use heterosis successfully and commercially in rice. Hybrid rice research was initiated in 1964, the genetic tools essential for breeding hybrid rice combinations, such as the cytoplasmic male sterile line (CMS line or A line), the maintainer line (B line) and restorer line (R line), were developed in 1973. Several hybrid combinations with good heterosis and higher yield potential were identified in 1974. The hybrid…     

K You 48-2

K You 48-2 is a new combination of early hybrid rice with good grain quality and high yield, developed by combining male sterile line K-Qing A having japonica cytoplasm and indica genome aodrestorer line Ce 48-2. In the regional trial of Hubei Province in 1991, its yield was 4.4% higher than that of the CK Weiyou 48-2,     

Studies on the seed production properties of Hunong 5s／Teqing 2

From Nongken 58s/Laser 4 // Xiandang, a photoperiod-sensitive genie male sterile indica rice line, Hunong 5s was developed, and authorized by Hubei Province in 1992, and by the Committee of the State Science Foundation of China in 1993, Hunong 5s was crossed to a indica restorer line Teqing 2 to produce a twoline F1 hybrid Hunong 5s/Teqing 2.     

Breeding of WA type male sterile line with wide compalibility gene

Exploration of the strong heterosis of intersubspecies cross of rice has been hindered by the sterility problem in indica/japonica hybrids. Such incompatibility can be overcome by incorporation of the wide compatibility gene S_5~(11) into indica or japonica breeding lines. An alternation is to develop male sterile lines with S_5~n. From a cross of Zhenshan 97B, the main tainer line of WA type male sterile line Zhenshan 97A, with Pecos, a wide compatibility line from USA, a WA type male sterile line with wide compat ibility named as Shanqin A was successfully developed through successive selling and baekcrossing simultaneously (see figure).     

K You 48-2 Developed by Rice and Sorghum Res Inst,Sichuan Acad of Agri Sci

K You 48-2 is a new combination of early hybrid rice with good grain quality and high yield, developed by combining male sterile line K-Qing A having japonica cytoplasm and indica genome and restorer line Ce 48-2. In the regional trial of Hubei Province in 1991, its yield was 4.4% higher than that of the CK Weiyou 48-2, being significant at 0.05 level. In the same year, in another regional trial of Sichuan Province, its yield was 8.9% higher than that of the CK Weiyou 48-2, being significant at 0.01 level. It has the highest yield among all tested varieties in both provincial trials. It has shown good grain quality with 60% head rice recovery and moderate resistance to rice blast.     

Geographic patterns of genetic diversity and fertility restoration ability of Asian and African origin pearl millet populations

A set of 45 diverse Asian and African origin/bred populations of pearl millet were investigated multi-locationally for morphological traits including grain yield and assessed for their fertility restoration ability on three cytoplasmic male sterility(CMS) systems in two contrasting seasons. Significant genetic variation was found for all the yield linked traits. Multivariate analysis for grain yield and its component traits grouped these populations into five clusters. Most of the Asian origin populations grouped into single cluster(Cluster III) and separated from the rest of the African origin populations indicating the presence of correspondence between clustering pattern and geographical origin of the populations. Clusters dominated with Asian populations(As-As) had linkages with early flowering, short plant height, more number of tillers, small and thin panicles, small seeded and low grain yield compared to the clusters dominated by African populations(Af-Af) or African origin and Asian bred(Af-As) populations.Genetically related populations having common parentage were found grouped in same clusters.Fertility restoration/maintainer frequency of 45 populations on three diverse CMS systems revealed that overall fertility restoration frequency was highest for A1(86%) followed by A4(37%) and for A5(7%) CMS system. Five populations were identified as potential sources for developing maintainer lines for all three CMS systems and eight populations were identified specifically for A;and A;CMS systems. A set of 11 and four populations were identified for restorer line development exclusively for A;and A;CMS system,respectively. Six populations were identified for the development of dual restorers for both A;and A;CMS system.     

Xinyou 752:a new hybrid rice combination with new cytoplasm resource,high yield and good quality

Xinyou 752(Xinlu A/752),developed by theRice Research Institute of Jiangxi Academy ofAgricultural Sciences,was released in Mar,1997 by Jiangxi Seed Board,named Xinyougan22.Till 1998,it had been planted 150000 hafor demonstration in southern China. Xinlu A is an indica CMS line with newcytoplasm resource from Lituo,a japonica ricefrom USA.Its 1000-grain weight is 29.2g,protein content 12.3％,and amylose content13.9％.The fertility of the CMS line is com-pletely abortive and its restorability resemblesthat of WA.It has strong combining abilityand earlier maturity.The restorer line,752,is from the cross of Erliu-Zaizao/BG 910-11. In the national trial of indica hybrid ricewith early and middle maturity in 1996,theaverage yield of Xinyou 752 was 7.0t/ha,8.77％ more than that of the CK,Shanyou10.In the same trial in 1997,its average yieldwas 6.8t/ha,6.81％ more than that of theCK,Shanyou 10.This combination could yield7.8-10.1t/ha under high fertilizer and proper     

Development of Novel Cytoplasmic Male Sterile Source from Dongxiang Wild Rice (Oryza rufipogon)

This study was conducted to develop and characterize a novel cytoplasmic male sterile(CMS)source which was identified from Dongxiang wild rice(Oryza rufipogon)by crossing Dongxiang wild rice as female with Zhongzao 35,an indica inbred variety,as male and continuous backcrossing with Zhongzao 35.Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm(CMS-WA).Sequential planting showed that this novel CMS has complete and stable male sterility.Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm(CMS-HL)and other indica inbred varieties are the maintainers with complete maintaining ability,suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS.So far,we only discovered a unique fertility restoration source for this novel CMS.Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes.Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.     

Development of New InDel Marker to Detect Genotypes of Rf-la Conferring Fertility Restoration of BT-Type Cytoplasmic Male Sterility in Rice

Restorer line breeding is an important approach to enhance the heterosis and improve the yields of japonica hybrid rice. To improve the selection efficiency of restorer lines for BT-type cytoplasmic male sterility （CMS） in japonica rice, a functional marker InDeI-Rf-la based on the difference of nucleotide sequence in Rf-la locus between BT-type CMS lines and restorer lines was developed to detect the genotypes of different rice materials. Conventional indica rice varieties, restorer and maintainer lines without 574 bp deletion could restore the fertility for BT-type CMS in japonica rice. By contrast, most conventional japonica rice varieties except Aichi 106 and Yijing 12, with genotype of rf-larf-la showed the 574 bp deletion maintained sterility for BT-type CMS lines. To further verify the effect of genotyping detection in Rf-la locus, this marker was also used to amplify the genomic DNA in different japonica rice restorer lines, CMS lines, hybrids and F2 segregation population, and three genotypes in Rf-la locus could be distinguished distinctly. Therefore, the marker InDeI-Rf-la could be widely used for genetic id~ntifio.~tinn ~nd m~rkp.r-~.~.~i~fp.d .~.tAr.tinn （MA.~ in hr~=dinn i~nnnir~ r~fnr~=r lin==~     

Xinxiangyou 77,a High-yielding and Fine-quality Semi-aromatic Hybrid Rice

Xinxiangyou 77 was developed at HHRRC using aromatie cytoplasmic male sterile line Xingxiang A and nonaromatic restorer line Minghui 77. It was extensively tested and approved for release to farmers by the Hunan Provincial Crop Variety Release Committee in February,1997. Xingxiang A, improved from the first aromatic     

香型优质杂交稻新香优63的选育与应用

新香优63由香型优质不育系新香A与明恢组选育而成，其产量水平略高于汕优63，但其稻米品质却明显优于汕优63，且部分米粒具有香味，该组合2000年通过贵州省贵阳市品种审定，2001年2月通过湖南省品种认定。     

利用香稻改良杂交水稻稻米品质

To improve grain quality of the high-yielding hybrid rice in China, we introduced the aromatic rice MR365, an improved Indian cultivar with aroma and other desirable grain quality characters such as long grain and low chalkiness, from IRRI in 1984 and began to transfer its aroma and good quality characters into the existing maintainer lines with good combining ability but poor grain quality. In the meantime, we also conducted the research on the inheritance of aroma for increasing the breeding efficiency. Through years of research and breeding practices, two cytoplasmic male sterile (CMS) lines Xiangxiang 2 A and Xinxiang A and a series of quasi-aromatic hybrids mated from these aromatic CMS lines have been developed and released for commercial production in China. It was found that the inheritance of aroma in MR 365 and its derivatives including Xiangxiang 2 A, Xinxiang A and Xiang 2B S was controlled by one pair of recessive major genes based on the identification of aroma by the KOH-soaking method. We also found that there existed disparity in aroma degree among different grains of F2 generation, and different aromatic CMS lines derived from the same aromatic donor such as Xiangxiang 2 A and Xinxiang A had also a little difference in the degree of aroma, which implies that, besides the major genes, aroma may also be affected by the genetic backgrounds or minor genes. Xiangxiang 2 A, developed from the cross of V20A∥V20B/MR365, is the first aromatic CMS line bred in China. It is not only aromatic but has good grain quality and combining ability. Using it as female parent, Xiangyou 63 (Xiangxiang 2A/Minghui 63), the first quasi-aromatic hybrid rice combination in China, was developed and approved to release to farmers in 1995. Xiangyou 63 is characteristic of quasi-aromatic or partially aromatic (because only a portion of or NOT ALL grains are aromatic), good grain quality, high-yielding ability, good blast resistance and wide adaptability. However, Xiangxiang 2 A has an evident drawback, i.e., instablility in male sterility under higher temperature conditions resulting from the existence of restoring minor genes in it, which greatly hampered the extension of its elite hybrid Xiangyou 63 with both high yield and fine quality in commercial production. To improve Xiangxiang 2 A, we made hybridization of Xiangxiang 2 B with V20 B again in 1990. A new aromatic CMS line Xinxiang A was successfully developed in 1994. It not only retains the favorable characteristics of Xiangxiang 2 A in grain quality and combining ability, but also expresses complete and stable male sterility and high seed production yield potential. Up to now, by using it as female parent, a series of quasi-aromatic hybrids have been developed. Some of them such as Xinxiangyou 63 (Xinxiang A/Minghui 63), Xinxiangyou 77 (Xinxiang A/Minghui 77), Xinxiangyou 80 (Xinxiang A/R80), Xinxiangyou 207 (Xinxiang A/R207) and Xinxiangyou 96 (Xinxiang A/R96) have been released to farmers. Such hybrids have been preferred and well welcome by the farmers in China, because they can not only yield higher or as high as but also possess a better grain quality than the current common high-yielding hybrid rice varieties, especially, they are naturally-mixed aromatic rice so that it can be consumed daily just like non-aromatic common rice. The planting area under these hybrids is increasing rapidly in China. It is expected that the quasi-aromatic hybrid rice will have a good prospect in the coming years.     

MR365的香味遗传及在杂交稻育种中的利用

以ＭＲ３６５及其作香味供体育成的香稻不育系湘香２号Ａ、新香Ａ、湘香２号Ｓ与Ｖ２０Ｂ、Ｖ４１Ｂ、珍汕９７Ｂ、明恢６３等非香亲本杂交,采用ＫＯＨ溶液法测定杂交组合Ｆ１、Ｆ２、Ｂ１Ｆ１植株和Ｆ２米粒的香味表现,结果表明,ＭＲ３６５的香味遗传受１对隐性核基因控制。在杂交水稻育种中,利用ＭＲ３６５育成了几个香稻不育系,并选配出一批香型杂交稻组合,其中香优６３、新香优７７、新香优８０等高产优质组合已通过省级审（认）定,具有较好的应用前景。     

MR365的香味遗传及在杂交稻育种中的利用

以MR365及其作香味供体育成的香稻不育系湘香2号A、新香A、湘香2号S与V20B、V41B、珍汕97B、明恢63等非香亲本杂交,采用KOH溶液法测定杂交组合F1、F2、B1F1植株和F2米粒的香味表现,结果表明,MR365的香味遗传受1对隐性核基因控制.在杂交水稻育种中,利用MR365育成了几个香稻不育系,并选配出一批香型杂交稻组合,其中香优63、新香优77、新香优80等高产优质组合已通过省级审(认)定,具有较好的应用前景.     

香型优质杂交稻新香优63的选育与应用

新香优63由香型优质不育系新香A与明恢63配组选育而成,其产量水平略高于汕优63,但其稻米品质却明显优于汕优63,且部分米粒具有香味.该组合2000年通过贵州省贵阳市品种审定,2001年2月通过湖南省品种认定.     

籼型香稻三系不育系贵香1A的选育

贵香1A是贵州大学水稻研究所育成的籼型香稻三系不育系,具有败育彻底,异交习性优良、配合力高、稻米品质较优等特点,2010年7月通过贵州省品种审定.     

籼型优质三系香稻不育系广泰A的选育及应用

广泰A是广东省农业科学院水稻研究所以保持系中间材料荣丰B//米31/W254为母本,具有香味的保持系中间材料天丰B/粤丰B为父本进行杂交,然后通过分子标记辅助选择具有香味且直链淀粉较低的F3代株系与印尼水田谷胞质不育系荣丰A测交,后经连续回交转育而成的优质香稻不育系.该不育系具有败育彻底、育性稳定、柱头外露率高、异交习...     

高蛋白香稻不育系绵香3A的选育与利用

绵香3A是绵阳市农业科学研究所以新香A为母本、大粒B香/改B的F2代优良单株为父本测交,经多代择优回交转育而成的野败不育胞质高蛋白三系香稻不育系。该不育系育性稳定,农艺性状优良,蛋白质含量高达15.5%,配合力强,所配组合产量高、米饭香味浓郁。绵香3A于2003年8月通过四川省技术鉴定,配制的组合绵香3优725于2005年3月通过陕西省农作物品种审定委员会审定。