浙北稻区杂交粳稻与常规粳稻优势比较分析

[目的]为杂交粳稻高产组合的选育及推广提供参考。[方法]以2002～2006年嘉兴市杂交晚粳稻与常规晚粳稻区域试验结果为材料,对其性状特点进行比较分析。[结果]杂交粳稻组合的分蘖率、株高和每穗粒数与常规粳稻品种相比有较强的竞争优势,但有效穗数少、成穗率和结实率偏低,增产不显著;稻瘟病抗性有了显著提高,但白叶枯病抗性偏差;垩白粒率和透明度有改观,碱消值略降,但其他品质性状与常规粳稻无差异。杂交粳稻组合的分蘖率、生育期、每穗粒数、结实率和千粒重等性状与产量呈不同程度的正相关,但株高与产量呈负相关。[结论]浙北稻区杂交粳稻高产新组合应朝穗、粒、重兼顾协调的方向发展。     

南方稻区单季杂交晚粳稻组合优势分析

南方稻区单季杂交晚粳稻组合优势分析结果表明,与单季常规晚粳相比,单季杂交晚粳组合主要在生物产量、每穗实粒数、千粒重、实际产量上有竞争优势,其他性状优势不明显,尤其是有效穗数及结实率偏低,是造成参试组合平均产量水平不高的主要原因;单季杂交晚粳组合主要品质性状与单季常规粳稻相比,整体水平高于常规品种,在出糙率和精米率上有竞争优势,但在外观品质和食味品质方面却低于常规品种。2年试验相关分析表明,杂交晚粳组合产量与主要农艺性状相关性和常规晚粳相比,存在较明显的差异,且年度之间差异较大。杂交晚粳组合产量与每穗实粒数呈极显著正相关,可能说明每穗实粒数是决定杂交晚粳组合产量的重要因素。对我国杂交晚粳稻发展中存在的主要问题和发展方向进行了探讨,提出了杂交晚粳稻育种应重视稻米外观品质的改良和食味品质的提高。     

江苏省杂交粳稻与常规粳稻主要性状比较

根据2004-2005年江苏省杂交粳稻和常规粳稻区域试验结果,比较了它们的主要农艺性状和品质性状。结果表明,与常规粳稻相比,杂粳组合主要农艺性状表现为在产量和穗粒结构上优势明显,穗大粒多,增产优势明显,但存在结实率偏低的问题;主要品质性状表现为整体水平低于常规品种,但杂交粳稻籽粒较长、较宽,具有一定的粒型优势。根据分析结果,对江苏省杂交粳稻发展中存在的问题和发展方向进行了探讨。     

江苏省杂交中粳与常规中粳产量要素比较

通过对2003年和2004年江苏省常规中粳和杂交中粳区域试验产量前三位品种产量要素的比较可知，杂交中粳的大穗大粒优势明显，杂种优势主要体现在穗粒等穗型指标上，而穗数等群体指标和结实率低于常规稻。利用常规粳稻的稳产性和丰产性，发挥杂交中粳的杂种优势，是提高江苏省粳稻产量的一个发展方向。     

杂交粳稻与常规粳稻主要性状的比较分析

对8个杂交晚粳稻与7个常规晚粳稻进行对比分析,结果表明,杂交粳稻组合的分蘖率、株高和每穗总粒数比常规粳稻品种有较强的竞争优势,表现单株分蘖强,植株高大,穗大粒多,产量优势明显,但有效穗数、成穗率和结实率为负优势,表现穗数偏少,成穗率和结实率偏低。提出今后嘉兴稻区杂交粳稻更高产新组合选育的方向和目标。     

杂交粳稻与常规粳稻农艺性状比较研究

通过试验研究认为,杂交粳稻新组合的丰产性比常规粳稻要好,其主要增产因子是穗大粒多,但有效穗和千粒重不及常规粳稻.杂交粳稻新组合的主要不足是植株偏高,结实率偏低.     

辽宁省杂交粳稻与常规粳稻产量性状相关分析

对11个辽宁省新育成的杂交粳稻品系与常规粳稻产量性状进行了比较,结果表明:杂交粳稻新组合的丰产性比常规粳稻好,其主要增产因子是穴穗重、株高、穴茎秆重、穗粒数;产量性状较好的杂交粳稻品系有5215、2015、9946、辽优3006、辽优5273、辽优5206.     

杂交粳稻与纯系粳稻收获指数比较研究

在南京和洪泽两地研究了５个杂交粳稻及其亲本和３个纯系粳稻的生物量、稻谷产量和收获指数。结果表明,当杂交粳稻的亲本包括在纯系粳稻内,杂交粳稻的生物量、稻谷产量极显著地大于纯系粳稻,而收获指数相反;当亲本不包括在内,杂交中熟中粳的生物量虽极显著地大于生产上栽培的纯系粳稻,但因收获指数相反,两者平衡后,稻谷产量无显著差异。生产上栽培的纯系粳稻生物量、稻谷产量和收获指数均极显著地大于杂交粳稻亲本。纯系矮秆粳稻的收获指数极显著地大于中秆粳稻,生物量极显著地小于中秆粳稻,稻谷产量无显著差异。粳稻保持系的生物量、稻谷产量极显著地大于粳稻恢复系,收获指数相反。     

江苏省杂交中粳与常规中熟中粳水稻主要性状的比较分析

[目的]对江苏省杂交中粳与常规中熟中粳水稻主要性状进行比较分析。[方法]利用2013—2016年江苏省杂交中粳和常规中粳区域试验数据,对新选育的杂交中粳与常规中熟中粳品种的主要农艺及品质性状进行比较分析。[结果]与中熟中粳相比,杂交中粳组合表现为植株高大、穗大粒多,但穗数较少、结实率偏低;主要品质性状表现为整体水平低于常规中熟中粳品种,但在整精米率和粒型上具有一定的优势。[结论]该研究为杂交粳稻育种的改良及推广提供参考。     

两系杂粳组合与三系杂粳组合杂种优势比较

比较两用核不育系Q226S、Q038S所配两系杂交粳稻组合及三系杂交粳稻组合杂种优势的构成后发现,无论哪类组合,其优势构成因素中,每穗总粒数、实粒数一般都具有正向优势,但两系组合穗、粒、重三因素结构更趋合理,这也是两系杂交粳稻组合可选性较强的主要原因。研究认为：保证一定的单株穗数,并中幅提高每穗结实粒数是当前杂交粳稻组合选育切实可行的路线。     

BT型不育系9703A的选育及其所配组合优势分析

9703A是用寒丰A与早熟晚粳9703转育而成的BT型三系不育系,具有农艺性状一致、不育性稳定、异交结实率高、容易制繁种等特点;所配组合矮秆抗倒,千粒重高,丰产性好,配合力水平高,具有较好的应用前景。9703A不育系及利用该不育系配组育成的新组合苏粳优3号(V优008)于2007年1月通过了江苏省农作物品种审定。     

Prospects of utilization of inter-subspecific heterosis between indica and japonica rice

The Asian cultivated rice(Oryza sativa L.) grown worldwide is divided into two subspecies, indica and japonica. It is well known that the heterosis of inter-subspecies is usually stronger than that of intra-subspecies. Since the 1970 s, indica hybrid rice, an intra-subspecific hybrid rice, has being widely used in China and even in the world. However, the inter-subspecific hybrid rice between indica and japonica is still unavailable. The major obstacle is the hybrid sterility of the inter-subspecies. In recent decades, the genetic and molecular basis of indica-japonica hybrid sterility was understood more and more clearly. Some breeding approaches for overcoming inter-subspecific hybrid sterility were proposed and used to develop the indicajaponica hybrid rice. The updated understanding will offer new approaches for development of breeding lines for overcoming indica-japonica hybrid sterility, which facilitates developing of inter-subspecific hybrid rice.     

杂交稻组合作再生稻种植品比试验

以广两优676为对照,进行杂交稻组合作再生稻种植品比试验,结果表明:杂交稻组合II优1273、天优3301、泸优明占表现产量高、米质优、整齐度好、适应性强,可进一步推广种植。     

Comparison of grain yield and quality of different types of japonica rice cultivars in the northern Jiangsu plain,China

In recent years, an increasing number of different types of japonica rice cultivars have been released in the southern rice region of China. The grain yield and quality of these new cultivars showed significant differences in large scale planting. However, the causes of the differences remain little known. Therefore, three typical types of japonica rice cultivars were used in this study to investigate their grain yield and quality. A scanning calorimeter(DSC), X-ray powder diffractometer(XRD), rapid viscosity analyzer(RVA) and taste analyzer were used to evaluate the cooking and eating properties. The results showed that the yield of non-soft hybrid japonica rice cultivars was significantly higher than that of non-soft inbred japonica rice cultivars and soft inbred japonica rice cultivars. Soft inbred japonica rice cultivars had a low amylose content and moderate protein content, which are the main reasons for the superior cooking and eating quality. In addition, the relative crystallinity of soft inbred japonica rice cultivars was significantly higher than that of non-soft inbred and non-soft hybrid japonica rice cultivars, which is considered the major factor resulting in higher transition temperature and gelatinization enthalpy(ΔHgel). Non-soft hybrid japonica rice cultivars had a higher number of large starch granules than soft inbred and non-soft inbred japonica rice cultivars. The setback value(SB) and breakdown value(BD), indirectly reflecting the cooking and eating quality of the three types of japonica rice cultivars, also confirmed that soft inbred japonica rice cultivars with a low SB value and a high BD value had better palatability than the other two types. This study provides guidance for future plantation of different types of japonica rice cultivars in large rice-producing areas.     

高产环境下韩国粳稻与云南粳稻主要性状的对比研究

在玉溪水稻高产栽培环境下,对引进的75个韩国水稻材料的经济性状与本地75个水稻材料进行对比研究。结果表明,韩国水稻材料分蘖力较强,结实率不高,但生育期偏短,穗型偏小,千粒重不高,因此,难于直接应用于生产,但大多数韩国水稻材料的米粒透明度要好于当地材料。研究结果为利用韩国水稻材料的优异性状改造本地品种（材料）提供了理论依据。     

四川省主要杂交稻组合DNA杂合性的比较

利用9个随机引物分析了近年来四川省选育的籼型杂交水稻新组合的DNA杂合性。结果表明,不同的引物揭示多态性的能力存在差异;同一引物在不同的水稻组合间扩增的多态性也不一样。14个组合DNA杂合性变异较小,分布于0.2283～0.3451之间。14个组合可以分为3类,但经t检验表明,13个组合与汕优63无显著差异。     

标记辅助改良热带粳稻利用水稻亚种间杂种优势

培育亚种间杂交水稻品种是开发水稻产量潜力的一个重要研究内容。本研究通过复合杂交结合分子标记辅助选择(MAS)培育出新型的籼稻基因渗入热带粳稻品系。这些基因渗入系表现出良好的农艺性状，经RAPD标记检测，遗传上更相似于热带粳稻，大部分品系具有广亲和特性。进一步用SSR和SSR-RAPD分子标记分析这些籼稻渗入系热带粳稻与3个温敏核雄性不育系间的遗传差异性，利用具有较大的分子标记多态性的组合亲本配制杂交稻种子，鉴定获得了多个具有强杂种优势的组合。结果表明，MAS是亚种问杂交水稻育种中辅助选择杂交亲本、鉴定广亲和位点、育种品系的遗传多样性和遗传距离分析和杂交稻组合选配的有效技术手段。     

Comparison of agronomic performance between inter-sub-specific hybrid and inbred japonica rice under different mechanical transplanting methods

Mechanical transplanting has been applied to rice cultivation to save labor costs and ease labor shortages in Asian countries, especially in China. However, little information is available related to the characteristics of agronomic performance when comparing inter-sub-specific hybrid rice (IHR) and inbred japonica rice (IJR) under mechanical transplanting method. In 2013 and 2014, field experiments were conducted using IHR (Yongyou 2640) and IJR (Wuyunjing 24) under two cultivation patterns, that is, pot seedlings mechanically transplanted (PS) and carpet seedlings mechanically transplanted (CS). Grain yield, yield components, leaf area index (LAI), leaf area duration (LAD), aboveground biomass, crop growth rate (CGR), nitrogen (N) uptake, and N accumulation were investigated. When compared with CS, PS displayed significantly increased grain yield for both varieties because the larger sink size allowed higher N accumulation from panicle initiation to maturity. Moreover, total aboveground biomass under PS increased significantly compared with that under CS; that is, higher photosynthetic productivity resulted from a greater LAI and higher LAD during the grain filling stage. Higher N absorption capacity in the middle and late growth periods resulted in significantly enhanced total N uptake under PS. When compared with IJR for both treatments, IHR generated 75.2% more grain yield. However, the characteristics creating high yield of IHR were different from those of IJR. Greater aboveground biomass production as well as higher N uptake and accumulation created higher grain yield in IHR than in IJR. These results suggest higher yield could be achieved using PS with IHR, attributing to exploit both yield superiority and productive potential.