japonica rice is mainly distributed in Northeast China and accounts for 44.6% of the total cultivated area of japonica rice in China. The comprehensive using of inter-subspecies heterosis is the main breeding mode of ...japonica rice is mainly distributed in Northeast China and accounts for 44.6% of the total cultivated area of japonica rice in China. The comprehensive using of inter-subspecies heterosis is the main breeding mode of super japonica rice varieties in this region. Improving rice quality at relative high yielding level is the current research focus. Performing crosses between indica and japonica lines allows for the recombination of regulatory genes and genetic backgrounds, leading to complicated genetic rice quality characteristics, which can be used to explore patterns of quality improvement. In the present study, we utilize recombinant inbred lines （RILs） derived from indica-japonica hybridization to analyze the effect factors of rice quality derived from genetic factors, which contain both regulatory genes concerning rice quality and genetic backgrounds＇ random introduction frequency coming from indica （Di value）, and the improvement strategy was further discussed. The regulatory genes involved in amylase content （Wx） and nitrogen utilization efficiency （NRT1.1B） were the major factors affecting the amylose content （AC） and protein content （PC） in RILs, respectively. Both the Di value and the major grain width gene （GS5） had regulatory effects on milled rice width （MRW） in RILs, and their interaction explained the major variance of MRW in the RILs. With the mediation of MRW and chalkiness degree （C）, Di value had a further impact on head rice rate （HR）, which was relatively poor when the Di value was over 40%. In Northeast China, the Di value should be lowered by backcrossing or multiple crosses during the breeding of indica-japonica hybridization to maintain the whole better HR and further to emphasize the use of favorable genes in individual selection.展开更多
Chunyou 284 is a medium- japonica hybrid combination,as well as an indica-japonica subspecific hyrbid with super-high yield,which was developed from Chunjiang 23A,a thermo-sensitive CMS line with very early anthesis t...Chunyou 284 is a medium- japonica hybrid combination,as well as an indica-japonica subspecific hyrbid with super-high yield,which was developed from Chunjiang 23A,a thermo-sensitive CMS line with very early anthesis time,and C84,an indica-japonica intermediate type restorer line with wide compatibility.This combination has the advantages of high yield potential,early maturity,excellent comprehensive agronomic traits and wide adaptability.It was approved by Jiangsu Provincial Crop Variety Approval Committee in June,2018.The breeding process,main characteristics,cultivation techniques and seed production points of the combination were introduced.展开更多
在大田条件下比较了5个超级稻品种和对照汕优63的物质生产及氮素吸收利用特性。结果表明,超级稻物质生产与积累优势始于拔节期,并随着生育进程而扩大,抽穗以后的干物质量积累优势明显。超级稻对氮素的吸收积累总量达196.5（184.3-200.8...在大田条件下比较了5个超级稻品种和对照汕优63的物质生产及氮素吸收利用特性。结果表明,超级稻物质生产与积累优势始于拔节期,并随着生育进程而扩大,抽穗以后的干物质量积累优势明显。超级稻对氮素的吸收积累总量达196.5（184.3-200.8）kg hm^-2,较对照的176.5kg hm^-2增加20.0kg hm^-2,其中拔节前与对照相当,拔节至抽穗期增加9.2kg hm^-2,抽穗至抽穗后25d增加4.9kg hm^-2,抽穗后25d至成熟期增加4.3kg hm^-2。氮素吸收速率拔节至孕穗阶段达最高峰,超级稻为3.68（3.44-3.96）kg N hm^-2d^-1,对照为3.55kg N hm^-2d^-1;孕穗期以后吸氮速率随着生育进程而逐渐下降,抽穗25d以后,对照基本不具再吸收能力,而超级稻仍具一定吸收能力（0.36kg N hm^-2d^-1）。超级稻生育中、后期氮素吸收利用能力的提高促进了抽穗和灌浆结实期植株特别是叶片含氮率的提高,孕穗期、抽穗期、抽穗后25d、成熟期叶片含氮率均与相应生育阶段的干物质积累量显著相关,与最终总生物量极显著相关。超级稻在10.5t hm^-2产量水平下的百千克籽粒吸氮量在1.83kg左右。展开更多
为阐明籼、粳超级稻茎秆抗倒支撑特征的差异,以当地主栽且具有代表性的2个超级杂交籼稻组合和2个常规粳型超级稻品种为试验材料,在稻麦两熟制条件下对籼、粳超级稻茎秆形态特征、充实性状和力学特性以及弯曲力矩、抗折力、倒伏指数、田...为阐明籼、粳超级稻茎秆抗倒支撑特征的差异,以当地主栽且具有代表性的2个超级杂交籼稻组合和2个常规粳型超级稻品种为试验材料,在稻麦两熟制条件下对籼、粳超级稻茎秆形态特征、充实性状和力学特性以及弯曲力矩、抗折力、倒伏指数、田间表观倒伏率和实收产量等进行了系统的比较研究.结果表明,1）粳稻实收产量较籼稻高12．30％,差异极显著；基部0~20 cm 节间抗折力极显著高于籼稻、倒伏指数极显著低于籼稻,没有出现明显倒伏现象,而籼稻扬两优6号和两优培九两年平均田间表观倒伏率分别达11．97％和12．50％；2）粳稻基部四个节间弯曲力矩均极显著小于籼稻,抗折力均极显著大于籼稻,最终粳稻基部第1至第4节间的倒伏指数均极显著低于籼稻；3）粳稻各节间长度和株高以及基部节间外径、秆型指数、单穗质量、重心高和相对重心高度均小于籼稻,差异显著或极显著,而穗下节间长/秆长粳稻极显著大于籼稻；4）粳稻六个伸长节间的茎秆粗度和茎壁厚度均小于籼稻,其中,基部第1至第4伸长节间的茎秆粗度达到显著或极显著水平；5）粳稻各节间茎秆干质量均小于籼稻,两优培九各节间叶鞘干质量极显著高于其他3个品种,且粳稻基部第2节间单位节间茎秆干质量略高于籼稻,而基部第1、3、4、5、6节间粳稻单位节间茎秆干质量均低于籼稻；6）粳稻单穴固持力和抗弯阻力均显著或极显著大于籼稻,而按压恢复度显著或极显著小于籼稻.可见粳稻固持抗倒能力较强,籼稻抗倒恢复能力较强,且粳稻能协调实现高产与抗倒,这可能与其弯曲力矩小、抗折力大、株高矮、节间配置合理、重心低以及基部节间物质充实足等有关.展开更多
基金sponsored by the National Natural Science Foundation of China(31371587,31430062)the Cultivation Plan for Youth Agricultural Science Technology Innovative Talents of Liaoning Province,China(2015035,2015036)the Program for Changjiang Scholars and Innovative Research Team in University,China(IRT13079)
文摘japonica rice is mainly distributed in Northeast China and accounts for 44.6% of the total cultivated area of japonica rice in China. The comprehensive using of inter-subspecies heterosis is the main breeding mode of super japonica rice varieties in this region. Improving rice quality at relative high yielding level is the current research focus. Performing crosses between indica and japonica lines allows for the recombination of regulatory genes and genetic backgrounds, leading to complicated genetic rice quality characteristics, which can be used to explore patterns of quality improvement. In the present study, we utilize recombinant inbred lines （RILs） derived from indica-japonica hybridization to analyze the effect factors of rice quality derived from genetic factors, which contain both regulatory genes concerning rice quality and genetic backgrounds＇ random introduction frequency coming from indica （Di value）, and the improvement strategy was further discussed. The regulatory genes involved in amylase content （Wx） and nitrogen utilization efficiency （NRT1.1B） were the major factors affecting the amylose content （AC） and protein content （PC） in RILs, respectively. Both the Di value and the major grain width gene （GS5） had regulatory effects on milled rice width （MRW） in RILs, and their interaction explained the major variance of MRW in the RILs. With the mediation of MRW and chalkiness degree （C）, Di value had a further impact on head rice rate （HR）, which was relatively poor when the Di value was over 40%. In Northeast China, the Di value should be lowered by backcrossing or multiple crosses during the breeding of indica-japonica hybridization to maintain the whole better HR and further to emphasize the use of favorable genes in individual selection.
基金Supported by National Key R&D Program of China(2017YFD0100405)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ASTIP-201X-CNRRI)+3 种基金Independent Research Project of State Key Laboratory of Rice Biology(2017ZZKT10204)the Major Scientific Technological Project of New Varieties of Agriculture(Grain)of Zhejiang Province(2016C02050-5-1)the Fundamental Research Fund for China National Rice Research Institute(2017RG003-1)Breeding of High-yield Genetically Modified Rice Varieties(2016ZX08001004-001)
文摘Chunyou 284 is a medium- japonica hybrid combination,as well as an indica-japonica subspecific hyrbid with super-high yield,which was developed from Chunjiang 23A,a thermo-sensitive CMS line with very early anthesis time,and C84,an indica-japonica intermediate type restorer line with wide compatibility.This combination has the advantages of high yield potential,early maturity,excellent comprehensive agronomic traits and wide adaptability.It was approved by Jiangsu Provincial Crop Variety Approval Committee in June,2018.The breeding process,main characteristics,cultivation techniques and seed production points of the combination were introduced.
文摘在大田条件下比较了5个超级稻品种和对照汕优63的物质生产及氮素吸收利用特性。结果表明,超级稻物质生产与积累优势始于拔节期,并随着生育进程而扩大,抽穗以后的干物质量积累优势明显。超级稻对氮素的吸收积累总量达196.5（184.3-200.8）kg hm^-2,较对照的176.5kg hm^-2增加20.0kg hm^-2,其中拔节前与对照相当,拔节至抽穗期增加9.2kg hm^-2,抽穗至抽穗后25d增加4.9kg hm^-2,抽穗后25d至成熟期增加4.3kg hm^-2。氮素吸收速率拔节至孕穗阶段达最高峰,超级稻为3.68（3.44-3.96）kg N hm^-2d^-1,对照为3.55kg N hm^-2d^-1;孕穗期以后吸氮速率随着生育进程而逐渐下降,抽穗25d以后,对照基本不具再吸收能力,而超级稻仍具一定吸收能力（0.36kg N hm^-2d^-1）。超级稻生育中、后期氮素吸收利用能力的提高促进了抽穗和灌浆结实期植株特别是叶片含氮率的提高,孕穗期、抽穗期、抽穗后25d、成熟期叶片含氮率均与相应生育阶段的干物质积累量显著相关,与最终总生物量极显著相关。超级稻在10.5t hm^-2产量水平下的百千克籽粒吸氮量在1.83kg左右。
文摘为阐明籼、粳超级稻茎秆抗倒支撑特征的差异,以当地主栽且具有代表性的2个超级杂交籼稻组合和2个常规粳型超级稻品种为试验材料,在稻麦两熟制条件下对籼、粳超级稻茎秆形态特征、充实性状和力学特性以及弯曲力矩、抗折力、倒伏指数、田间表观倒伏率和实收产量等进行了系统的比较研究.结果表明,1）粳稻实收产量较籼稻高12．30％,差异极显著；基部0~20 cm 节间抗折力极显著高于籼稻、倒伏指数极显著低于籼稻,没有出现明显倒伏现象,而籼稻扬两优6号和两优培九两年平均田间表观倒伏率分别达11．97％和12．50％；2）粳稻基部四个节间弯曲力矩均极显著小于籼稻,抗折力均极显著大于籼稻,最终粳稻基部第1至第4节间的倒伏指数均极显著低于籼稻；3）粳稻各节间长度和株高以及基部节间外径、秆型指数、单穗质量、重心高和相对重心高度均小于籼稻,差异显著或极显著,而穗下节间长/秆长粳稻极显著大于籼稻；4）粳稻六个伸长节间的茎秆粗度和茎壁厚度均小于籼稻,其中,基部第1至第4伸长节间的茎秆粗度达到显著或极显著水平；5）粳稻各节间茎秆干质量均小于籼稻,两优培九各节间叶鞘干质量极显著高于其他3个品种,且粳稻基部第2节间单位节间茎秆干质量略高于籼稻,而基部第1、3、4、5、6节间粳稻单位节间茎秆干质量均低于籼稻；6）粳稻单穴固持力和抗弯阻力均显著或极显著大于籼稻,而按压恢复度显著或极显著小于籼稻.可见粳稻固持抗倒能力较强,籼稻抗倒恢复能力较强,且粳稻能协调实现高产与抗倒,这可能与其弯曲力矩小、抗折力大、株高矮、节间配置合理、重心低以及基部节间物质充实足等有关.
