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水稻温敏型两用核不育系繁殖存在的问题及解决办法 总被引:2,自引:0,他引:2
水稻两用核不育系冷水串灌繁殖和海南冬繁存在安全性差、产量不高不稳、种子质量差等问题,已严重影响到两系法杂交水稻的健康发展.利用全国740个气象站点近50 a的历史气象资料,根据水稻两用核不育系育性敏感期可育和抽穗扬花期安全对温度的要求,运用计算机处理技术,研制出不同不育起点温度水稻两用核不育系最佳繁殖基地和时段的计算机决策系统,根据该系统筛选出不育起点温度为22℃的水稻两用核不育系最佳繁殖基地为云南省保山市,最佳育性敏感始期为8月3日.2010年在云南省保山市对不育起点温度为22℃的C815S进行了大面积繁殖,获得8.44 t/hm2的高产.介绍了在低纬度高海拔地区繁殖水稻两用核不育系所具有的优势和应注意的事项. 相似文献
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两系法杂交水稻研究和应用中若干问题的思与行 总被引:6,自引:0,他引:6
指出了当前我国两系法杂交水稻研究和应用中面临的主要问题,即两系法杂交水稻体系中不育系的称谓和分类不规范,生产上利用的水稻两用核不育系育性温光反应特性研究不清楚,水稻两用核不育系繁殖和两系法杂交稻制种基地选择不当等。针对当前情形,结合多年育种实践,提出了解决这些问题的对策及措施。建议将水稻两用核不育系分为长光高温不育型、高温不育型、短光低温不育型、低温不育型等四种类型。提出了水稻光温不育机理设想,即水稻光温敏核不育系育性转换是主效不育基因与其位置相近的发育感光基因或(和)发育感温基因相互作用的结果,微效不育基因可影响两用核不育系的不育起点温度。只有深入研究光温敏型不育系育性的光温组合效应,且获得具体的光温指标,才能更好地指导两系法杂交水稻制种和不育系繁殖。提出了水稻两用核不育系育性光温特性的鉴定方法以及两系法杂交稻种子生产应根据不育系育性温光特性和历史气象资料来合理安排基地和时段。 相似文献
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培育两系杂交稻是作物杂交优势利用育种领域中的一项重大革新。早在 1 973年 ,石明松发现水稻光敏核不育株农垦5 8S ,并于 1 981年提出两用核不育系概念 ,杂交水稻育种开始进入一个新的阶段即两系法阶段。两系法杂交优势利用 ,因其只需要光温敏核不育系和恢复系两个育种材料而得名。光温敏核不育系在低温或短日照条件下表现可育 ,自交结实繁殖种子 ;在高温或长日照条件下表现不育 ,可以用来与恢复系制种 ,生产杂交种子。由于光温敏核不育系能一系两用 ,与三系法相比 ,生产种子少了一个环节 ,便简化了种子生产程序。尤其是光温敏核不育系由… 相似文献
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概述了水稻两用核不育系育性转换规律、不育起点温度和育性漂移的研究,介绍了两用核不育系的选育途径与方法,分析了两用核不育系选育存在的主要问题,简述了两用核不育系选育的成果,并对今后的研究方向做了展望。 相似文献
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综述了水稻两用核不育性遗传背景、多样性产生的原因和光温因子对两用核不育系育性的影响。光照是诱导光敏型核不育水稻育性转换的主导因素,温敏型不育水稻育性表达起主要作用的因子是温度,水稻两用核不育系的不育性遗传比较复杂,F_2育性分离的遗传模式也不一致,有单基因遗传模式、双基因遗传模式、三基因遗传模式、质量—数量基因遗传模式和非典型分离模式等。 相似文献
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综述了籼型两用核不育系的繁殖途径和核心种子的生产,着重讨论了冷水串灌繁殖籼型两用核不育系的繁殖技术.认为对近年来选育成功的两系超级稻不育系亲本繁殖技术深入研究是今后的主攻方向. 相似文献
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湖北光敏核不育水稻的制种技术 总被引:2,自引:0,他引:2
光敏核不育水稻是一种新的水稻种质资源,其种子生产与三系水稻种子生产存在较大差异。(1)光敏核不育水稻可一系两用。在自然条件下,可在其不育期间制种,在可育期间繁殖。(2)利用人工长短光照可以诱导育性转换,进行少量的繁殖制种。(3)光长、温度影响育性稳定,是光敏核不育水稻制种最重要的限制因子。(4)杂交种保纯难度大。除了机械混杂、生物学混杂外,光敏核不育水稻还存在自身混杂,即在同一株生产出杂交种和不育系种子。 近年来,在光敏核不育水稻(简称二系,下同)杂种优势鉴定的同时,开展了对其亲本特性的观察及繁殖制种研究。1990年,湖北省… 相似文献
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《Plant Production Science》2013,16(2):189-198
AbstractGrain number per spike of wheat is lower in early sowing than in the conventional standard cultivation in Yamaguchi, Prefecture, Japan. Components of the grain number per spike in five cultivars were analyzed with respect to temperature during the spike development period throughout three growing seasons 2001/2002, 2002/2003 and 2003/2004 to find the cause of the problem of early sowing cultivation. The plants sown in early-October and late-November were called the early sown group and the standard group, respectively, in the following. Three of the five cultivars, Hokushin, Akitakko and Nanbukomugi, showed a strong winter habit, which requires very cold temperatures for spike differentiation. The other two cultivars, Iwainodaichi and Airakomugi, had a moderate winter habit. Grain number per spike and grain yield were decreased by early-sowing (compare with the standard group) in almost all cultivars throughout the three growing seasons. The three cultivars which had a strong winter habit had fewer spikelets per spike in the early-sown group than in the standard group. The other two cultivars which had a moderate winter habit had fewer grains per spikelet in the early-sown group. The higher the temperature during the spikelet formation phase, which is from flag leaf initiation to terminal spikelet initiation, the higher the number of spikelets per spike in the standard group. The spikelet number per spike in the early-sown group increased with the increase in productive tillers under fertile conditions. Such conditions also increased the grain number per spike. 相似文献
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《Journal of Crop Improvement》2013,27(2):415-432
Summary This paper reviews the effects of allelopathic interactions in agroecosystems in Spain on plant physiological activity and their ecological advantages. The phenological stage of growth of donor plants and the effective allelochemicals in the soil solution while studying the role of phenolic compounds were highlighting. Finally possible future prospects and conclusions regarding weed control by allelochemi-cals under integrated crop management strategies are discussed. 相似文献
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以翔实的资料对2009年中国稻米生产、消费、进出口、供求平衡、库存、价格走势、购销政策和国际稻米供求等情况进行了全面地分析,对影响2010年稻米市场价格走势的各种因素进行了深入研究,并在此基础上对2010年我国稻米市场价格走势进行了预测,结论是我国稻米价格仍呈上行趋势。 相似文献
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Corné Kempenaar Thomas Been Johan Booij Frits van Evert Jean-Marie Michielsen Corné Kocks 《Potato Research》2017,60(3-4):295-305
Precision agriculture is a farming management concept based on observing, measuring and responding to inter- and intra-field variability in crops. In this paper, we focus on responding to intra-field variability in potato crops and analyse variable rate applications (VRAs). We made an overview of potential VRAs in potato crop management in The Netherlands. We identified 13 potential VRAs in potato, ranging from soil tillage to planting to crop care to selective harvest. We ranked them on availability of ‘proof of concept’ and on-farm test results. For five VRAs, we found test results allowing to make a cost-benefit assessment. These five VRAs were as follows: planting, soil herbicide weed control, N side dress, late blight control and haulm killing. They use one of two types of spatial data: soil maps or biomass index maps. Data on costs and savings of the VRAs showed that the investments in VRAs will pay off under practical conditions in The Netherlands. Savings on pesticide use and N-fertilizer use with the VRAs were on average about 25%, which benefits the environment too. We foresee a slow but gradual adoption of VRAs in potato production. More VRAs will become available given ongoing R&D. The perspectives of VRAs in potatoes are discussed. 相似文献
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Summary Diurnal changes in net photosynthetic rate were measured in a furrow-irrigated potato crop and in a riverbed crop where the
water table was always maintained at 20–28 cm from the soil surface. In the irrigated crop, the photosynthetic rate during
mid-afternoon was about half the peak rate observed at noon. This reduction was accompanied by a near tripling of stomatal
resistance, a 45% reduction in transpiration, and a 5-fold increase in the difference between leaf and air temperatures. No
such changes were observed in the riverbed crop where the photosynthetic rate remained nearly constant at about 0.9 mg m−2 s−1 between 9 a.m. and 4 p.m. Tuber yield in the riverbed crop was about 30% higher than in the irrigated crop. 相似文献
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体细胞无性系变异是一种重要的细胞工程育种技术,其应用于棉花育种的前提是建立高效的组织培养诱导再生植株体系.本文简要综述了棉花离体诱导植株再生研究的现状,重点讨论了棉花体细胞无性系变异的表现、利用方法及机理,提出了当前研究存在的问题并对今后的研究进行了展望. 相似文献