水稻理想株型的研究进展

介绍了理想株型的涵义及发展历史，并从茎、叶片、穗、根系等4个方面，对水稻理想株型的研究进展进行了综述，提出了理想株型必须适应当地生产实际和生态条件、建立生态适应理想株型育种指标数学模拟体系等未来水稻理想株型研究的6个方向。     

水稻理想株型育种研究进展

理想株型与杂种优势利用相结合是实现水稻单产突破的重要途径之一。综述了理想株型的概念、株型构成因子及其相互关系、国内外株型育种的主要理论及存在的问题。提出了动态理想型的株型观点和水稻动态理想型的主要塑造途径,对水稻动态理想型育种进行了展望。     

浅谈水稻理想株型育种

简述了理想株型的发展历史及株型育种经历的三个发展阶段,阐述了理想株型的形态特征、理想株型育种的理论基础、应用这一理论所取得的成果以及发展前景。提出了进一步发挥水稻的高产潜力是理想株型与杂种优势利用相结合。     

水稻株型的分子机理研究进展

株型是水稻产量的重要决定因素，创制理想株型品种是提高水稻产量的重要途径。20世纪50年代的矮化育种和70年代的杂交水稻培育是水稻增产的两次革命，但近几年水稻产量增长放缓，通过理想株型与杂种优势的结合进而实现超高产将成为第三次育种革命的关键。本文简要回顾了水稻株型分子调控机理的最新研究概况，重点关注了叶形、穗型和粒型等方面所取得的进展，并展望了水稻理想株型未来的研究趋势，为通过分子设计育种创制水稻理想株型，进一步提高水稻产量提供参考。     

浅谈水稻理想株型育种

简述了理想株型的发展历史及株型育种经历的三个发展阶段，阐述了理想株型的形态特征、理想株型育种的理论基础、应用这一理论所取得的成果以及发展前景。提出了进一步发挥水稻的高产潜力是理想株型与杂种优势利用相结合。     

两份新株型水稻品系的农艺性状与遗传特性分析

[目的]理想株型水稻能提高光合作用效率、经济产量和抗病能力.通过探究两份新株型水稻种质的农艺性状变异和遗传特性,为水稻高产抗病育种提供优异理想株型种质资源.[方法]以两个重组自交系中发现的两份自然重组的新株型种质08yi和RIL60以及由同一自交系选育出来的常规种质08yc和RILc为材料,进行不同生长时期的株型构成因...     

水稻理想株型的遗传基础研究

水稻是我国最主要的粮食作物之一,20世纪50年代矮源基因在育种中的应用和70年代杂种优势的利用使水稻产量实现了两次飞跃。近年来,虽然水稻产量徘徊不前,但基于理想株型的综合设计让水稻产量的新突破成为可能。本文从水稻根、茎、叶、穗、分蘖等几部分的遗传进展综述了水稻理想株型的设计塑造。     

水稻理想株型研究综述

理想株型与杂种优势利用相结合是实现水稻单产突破的重要途径之一。本文综述了理想株型的概念、发展历史、各株型构成因子研究状况和存在的问题。阐述了理想株型与环境优势达到最大的统一才能使水稻获得高产优质的观点,并提出了实现这一观点应采取的措施。     

水稻理想株型的研究进展

本文就水稻理想株型的特征特性和株型栽培的研究现状进行了综述,并提出了今后水稻株型研究的方向。     

超级稻高产栽培株型模式

在２０世纪中期 ,日本的Ｔｓｕｎｏｄａ就提出高产水稻株型应该是茎秆矮壮挺立 ,叶片短且直立。松岛省三认为多穗、矮秆、短穗是高产株型。在我国自杨守仁提出水稻高产理想株型以来 ,许多水稻专家也相继提出各自的高产理想株型模式 ,如袁隆平提出高产水稻功能叶为“长、直、窄、凹、厚”的株型模式 ,黄耀祥提出“半矮秆丛生快”超高产株型模式 ,周开达提出“重穗型”株型。近年来 ,随着超级稻集成技术的形成与示范推广 ,对水稻超高产株型模式又有了新的认识和发展。通过对协优９３０８高产栽培株型模式的研究 ,对于超高产栽培和育种具有深远…     

Practice and Thought on Developing Hybrid Rice for Super High Yield by Exploiting Inter-subspecific Heterosis

Since the breakthrough of grain yield owing to the development of dwarf rice and three-line system hybrid rice, rice breeding for high yield hardly had showed significant progress in the next successive two decades. It was considered that utilizing heterosis between subspecific varieties (Oryza sativa L.) would be an effective approach to increase yield further. During 1987-1993,an indica-japonica hybrid Yayou 2 yielded as high as 10.5 t/ha; however, it failed to be commercialized because of seed purity problem due to non-uniform emasculation by chemical agent in seed production, and sensitivity of seed setting in F1 plants to environmental conditions. In the past decade, two inter-subspeific hybrids, Liangyoupeijiu (Peiai 64S/9311, javanica/indica) and Liangyou E32 (Peiai 64S/E32, javanica/japonica); both of them exhibited grain yield higher than 10.5 t/ha, and were widely judged as the pioneers of super hybrid rice. Liangyoupeijiu has been successfully popularized over 4 million hectare in wide climatic areas, while Liangyou E32 made a yield record and offered a model of plant ideotype for super hybrid rice. It was considered that in combination with plant ideotype, active physiological functions, and wide-range adaptability to ecological conditions, exploitation of indica-japonica heterosis would be the key approach for super hybrid rice breeding.     

Progress in ideotype breeding to increase rice yield potential

The ideotype approach has been used in breeding programs at the International Rice Research Institute (IRRI) and in China to improve rice yield potential. First-generation new plant type (NPT) lines developed from tropical japonica at IRRI did not yield well because of limited biomass production and poor grain filling. Progress has been made in second-generation NPT lines developed by crossing elite indica with improved tropical japonica. Several second-generation NPT lines outyielded the first-generation NPT lines and indica check varieties. China's “super” rice breeding project has developed many F₁ hybrid varieties using a combination of the ideotype approach and intersubspecific heterosis. These hybrid varieties produced grain yield of 12 t ha⁻¹ in on-farm demonstration fields, 8–15% higher than the hybrid check varieties. The success of China's “super” hybrid rice was partially the result of assembling the good components of IRRI's NPT design in addition to the use of intersubspecific heterosis. For example, both designs focused on large panicle size, reduced tillering capacity, and improved lodging resistance. More importantly, improvement in plant type design was achieved in China's “super” hybrid rice by emphasizing the top three leaves and panicle position within a canopy in order to meet the demand of heavy panicles for a large source supply. The success of “super” hybrid rice breeding in China and progress in NPT breeding at IRRI suggest that the ideotype approach is effective for breaking the yield ceiling of an irrigated rice crop.     

高产花生理想株型的研究

粮食安全是涉及国家稳定和发展的重大战略问题。花生作为重要的油料作物,对解决我国油料供应矛盾具有重要作用。近年来,我国花生产业得到稳步提高,花生育种工作也得到了长足发展,但以目前花生生产状况而言,若要进一步发挥花生生产潜力、提高花生产量,须要借鉴小麦、水稻和玉米三大作物的理想株型研究。本文以花生往年高产创建的株型等相关参数,提出了花生高产理想株型以期指导花生育种工作和花生高产攻关,进一步促进我国花生高产。     

提高水稻杂种优势水平的可能途径

 杂交水稻的单产处于徘徊状态。提高单产的可靠途径在于扩大双亲的遗传差异, 进一步提高杂种优势水平。培育“杂交水稻超高产群体理想型”, 应用分子标记辅助相互轮回选择法累加不同组群的优势基因和应用分子标记技术挖掘与利用野生稻中的远缘优势基因, 有可能大幅度地提高杂交水稻的单产潜力。     

Agronomic performance of rice breeding lines selected based on plant traits or grain yield

Selection for yield per se has greatly contributed to yield improvement in many crops. It is expected that selection based on plant traits is more effective in increasing crop yield potential. This study was conducted to compare the effectiveness of trait-based and yield-based selection in increasing rice yield and to determine whether lines with ideotype traits have the potential to express higher yield under optimal crop management conditions. Lines were selected based on plant traits or on grain yield measured in a breeder's replicated yield trial. The main target traits for selection were plant height, leaf and panicle morphology, grain size, total dry weight, and grain-filling percentage. Yield performance of trait-based selection was compared with that of yield-based selection in an agronomic trial with optimum crop management for three seasons. Trait-based selection increased leaf area index and total dry weight but reduced spikelet number per m² and harvest index compared with yield-based selection. Consequently, selection based on plant traits did not increase grain yield compared with selection based on yield per se. In one of the three seasons, yield of trait-based selection was significantly lower than that of yield-based selection. Among all tested breeding lines, maximum yield was produced by yield-based selection and minimum yield came from trait-based selection. These results suggest that lines with ideotype traits did not express higher grain yield than lines selected based on yield per se under optimal crop management conditions, and yield-based selection was as effective in increasing rice grain yield as trait-based selection in the late generations of the breeding cycle.     

将乐县水稻新品种试种筛选浅析

引进9个省内外水稻优质新品种在将乐县进行了试种,筛选出了3个植株形态好、产量高、抗倒伏、抗稻瘟病等综合性状好的品种,其中嘉糯1优6号产量达10444.5kg/hm^2,丰优559产量达9178.5kg/hm^2,天优3301产量达8683.5kg/hm^2,适合于在将乐县种植。     

Ideotype breeding for submergence tolerance and cooking quality by marker-assisted selection in rice

Submergence tolerance and jasmine-like cooking quality are desirable for rice varieties grown in rainfed and irrigated lowland ecosystems in the Mekong region of Southeast Asia. Hybridization between varieties IR57514 and Kao Dawk Mali 105 (KDML105) was initiated with the goal of producing an ideotype that combines submergence tolerance and jasmine-like cooking quality. Through the single seed descent (SSD) method, a large population of recombinant inbred lines (RILs) was developed, and we demonstrated the potential of using marker-assisted selection (MAS) in the identification of the ideotype from the offspring. Four markers, R10783Indel, Waxy, Aromarker and GT11, were used to select the favored alleles of the Sub1, Wx, badh2 and SSIIa loci, respectively. The ideotype was classified into two groups: ideotype1 (ID1), carrying the Sub1^IR, badh2^KD, Wx^KD and SSIIa^KD alleles and consisting of 66 RILs and ideotype2 (ID2), carrying the Sub1^IR, badh2^KD, Wx^KD and SSIIa^IR alleles and consisting of 31 RILs. Submergence tolerance, cooking quality, grain quality and agronomic characteristics of the IDs were evaluated and compared with those of the parents. All of the ID1 lines exhibited submergence tolerance and jasmine-like cooking quality and displayed a low amylose content, a fragrance and a high alkali spreading value, whereas the ID2s showed the same characteristics as ID1, except for a low alkali spreading value, which was inherited from IR57514. A wide range of agronomic characteristics was observed in both of the ID groups, and some of the IDs were superior in the yield component, as compared to their parents. This study provides further support that the precision of markers used in MAS can enhance the development of ideotypes in rice.     

Construction of SSR Linkage Map and Analysis of QTLs for Rolled Leaf in Japonica Rice

Genetic analysis of rolled leaf is important to rice ideotype breeding. To detect loci controlling rolled leaf of japonica restorer lines, SSR marker genotypes and phenotypes of flag leaf rolling index (LRI) were investigated in Xiushui 79 (P1, a japonica rice variety), C Bao (P2, a japonica restorer line) and 254 recombinant inbred lines derived from the cross between P1 and P2 , and in two environments. A genetic map of this cross was constructed, QTLs for LRI were detected and their interactions with environments were analyzed. Among 818 pairs of SSR primers, 90 primers showed polymorphism between P1 and P2, and 12 markers showed highly significant correlation with LRI in both environments based on single marker regression analysis. The genetic map containing 74 information loci has a total distance of 744.6 cM, with an average of 10.1 cM between two adjacent loci. Three QTLs (qRL-1, qRL-7 and qRL-8-1) were detected with two softwares: WinQTLCart 2.5 and QTLNetwork2.0. qRL-8-1 was a new locus, accounting for 15.5% and 12.8% of phenotypic variations in the two environments, respectively. The phenotypic variation explained by additive effect was 6.6%. No interaction was found between qRL-8-1 genotype and environments.     

Yield potential and radiation use efficiency of “super” hybrid rice grown under subtropical conditions

China's “super” hybrid rice breeding project has developed many new varieties using a combination of the ideotype approach and intersubspecific heterosis. It is controversial whether these “super” hybrid varieties have increased the yield potential of irrigated rice. This study was conducted to compare grain yield and yield attributes among “super” hybrid, ordinary hybrid, and inbred varieties. Field experiments were done in Liuyang (moderate-yielding site) and Guidong (high-yielding site) counties, Hunan Province, China, in 2007 and 2008. Two varieties from each varietal group were grown in each field experiment under moderate and high N rates. Grain yield, yield components, aboveground total dry weight, harvest index, total N uptake, and crop radiation use efficiency (RUE) were measured for each variety. A significant difference in grain yield was observed among the varieties and varietal groups but not between the two N rates. “Super” hybrid varieties have increased rice yield potential by 12% compared with ordinary hybrid and inbred varieties. The higher grain yield of “super” hybrid varieties was attributed to improvement in both source and sink. “Super” hybrid varieties produced more biomass than ordinary hybrid and inbred varieties. Long growth duration and high accumulated incident radiation were partially responsible for high biomass production for the “super” hybrid varieties. “Super” hybrid varieties had significantly larger panicle size (spikelets per panicle) than ordinary hybrid and inbred varieties, which resulted in larger sink size (spikelets per m²). Crop RUE did not explain the yield superiority of “super” hybrid rice. Our study suggests that “super” hybrid rice varieties do not necessarily require more N fertilizer to produce high grain yield.