共查询到20条相似文献,搜索用时 828 毫秒
1.
2.
3.
水稻最适叶面积指数和总颖花数的品种差异 总被引:4,自引:0,他引:4
以淮北地区不同历史年代的水稻品种为试验材料,研究叶面积和颖花量与品种产量能力进展的关系。结果指出:随品种最适叶面积指数和适宜总颖花量的增加,水稻品种的产量能力明显提高。因此确认高产品种选育应以增加最适叶面积指数和颖花量并适当减少穗数,应用半矮秆基因为途径。本文根据试验资料提出了目前淮北主要水稻品种的适宜群体指标,为良种选育和高产栽培提供依据。 相似文献
4.
5.
7.
8.
越南水稻品种资源分类及其利用状况 总被引:2,自引:0,他引:2
通过2000-2001年水稻品种资源调查,越南现有水稻品种676个,年种植面积583.73万hm2.越南水稻品种资源可分为国内选育品种、国外引进品种、地方品种3大类,前2类品种又分为已通过国家审定注册和未审定注册2种.国内选育的水稻品种370个,年种植面积255.54万hm2,其中已审定注册的品种为74个,年种植面积188.75万hm2;国外引进水稻品种119个,年种植287.67万hm2,其中已审定注册的水稻品种19个,年种植面积192.35万hm2;地方品种187个,年种植面积40.52万hm2. 相似文献
9.
水稻耐盐育种研究进展 总被引:2,自引:0,他引:2
培育耐盐水稻品种是盐碱地的粮食作物增产和对盐碱地改良的重要途径之一。水稻对盐胁迫中度敏感,其耐(敏)盐性状是受多基因控制的数量性状,易受环境条件等因素影响。到2015年,利用AFLP、RFLP、SSR等分子标记手段在水稻12条染色体上定位的耐盐QTL已有250多个,其中以第1、2、6和7染色体上居多,但克隆的水稻耐盐基因相对较少。水稻耐盐品种的选育现仍以常规育种为主,即主要通过筛选耐盐种质及耐盐鉴定,再利用杂交和回交等方法将耐盐基因导入到优良水稻品种中,从而选育出综合性状优良的耐盐品种。本文阐述了国内外水稻种质耐盐性鉴定技术和指标、耐盐种质筛选、耐盐品种选育以及耐盐性的遗传及分子机理等研究进展,并对今后水稻耐盐育种研究工作提出了展望与建议。 相似文献
10.
盐胁迫对水稻的影响及水稻耐盐育种研究 总被引:4,自引:0,他引:4
盐胁迫是盐渍化地区水稻生产的主要制约因素之一。盐胁迫对水稻的形态发育及生理生化代谢产生不利影响,其作用机理主要表现在渗透胁迫和离子毒害等。耐盐水稻品种的选育方法主要是筛选耐盐材料,将常规选育和转基因、分子标记辅助选择等现代生物技术相结合,选育耐盐性强且具有实用价值的品种。 相似文献
11.
《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
12.
《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
13.
14.
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
15.
16.
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
17.
18.
19.
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
20.
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