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121.
不同小麦品种籽粒灌浆特性的研究 总被引:8,自引:1,他引:8
以黄淮南片主产麦区广泛种植和新近育成推广的12个小麦品种为供试材料,对籽粒灌浆特性进行研究.结果表明:籽粒平均灌浆速度及最大灌浆速度均与百粒重、籽粒体积和籽粒最大体积呈极显著的正相关;籽粒灌浆持续期仅与饱满指数呈显著的正相关,而与百粒重无显著相关.供试品种的籽粒平均灌浆速度和最大灌浆速度,均以郑州853、陕农7859为最快,灌浆持续期最短,属晚花基因型品种;冀麦5418和徐州21的灌浆持续期最长,属早花基因型品种.还探讨了黄淮麦区南片小麦籽粒灌浆模式. 相似文献
122.
大豆重组自交系群体荚粒性状的QTL分析 总被引:16,自引:1,他引:16
利用大豆重组自交系soy01群体中的255个家系进行2年田间试验,采用两种作图方法,寻找一粒荚、四粒荚、每荚粒数等5个荚粒性状稳定的QTL。结果表明,利用区间作图法,2年共找到24个荚粒性状QTL,解释的遗传变异为5%~80%;利用复合区间作图法,2年共找到27个荚粒性状QTL,解释的遗传变异为4%~73%。利用复合区间作图法,2年找到2个重复出现、稳定的四粒荚QTL和2个每荚粒数QTL,为大豆荚粒性状QTL的精细定位和分子标记辅助育种提供了基础和依据。 相似文献
123.
黑龙江春玉米种植区高产品种籽粒灌浆、脱水特性及产量分析 总被引:1,自引:3,他引:1
为了研究不同高产玉米品种在黑龙江春玉米区种植的可行性,以‘先玉335’和‘郑单958’为试材,通过对比分析,探讨2个品种在该地区种植的灌浆和脱水特性。结果表明,‘先玉335’灌浆迅速,生理性脱水快,产量高;‘郑单958’灌浆持续期略长,前期和中期灌浆速率较‘先玉335’慢,但后期灌浆速率和自然性脱水速率都快,产量较高。从气温和降雨特点来看,在黑龙江春玉米种植区部分积温较高地区,可考虑将‘郑单958’作为品种更替及多样化的备选材料。 相似文献
124.
Summary The genetic variation for seed yield losses and the response to selection for reduction of such losses was studied by a six-week delay in the timing of harvest in various segregating populations from four lentil crosses. The bulk segregating populations had previously been subjected to different numbers of selection by means of a delayed harvest. The loss in seed yield from a delayed harvest in the two seasons 1981/82 and 1982/83 accounted for 551 and 105 kg/ha seed, representing 34 and 11% of the yield from a correctly timed harvest respectively. Pod drop accounted for 65% of this loss, whereas dehiscence gave 35% of the loss in both seasons. The parents of cross 4 differed significantly for pod dehiscence, with genotype 74TA 550 showing relative indehiscence. Selection by means of a delayed harvest of bulk populations decreased pod dehiscence, mean seed weight and bulk mean yield. 相似文献
125.
Fine mapping of the genetic locus L1 conferring black pods using a chromosome segment substitution line population of soybean 下载免费PDF全文
Qingyuan He Hongyan Yang Shihua Xiang Dong Tian Wubin Wang Tuanjie Zhao Junyi Gai 《Plant Breeding》2015,134(4):437-445
The colour of plant organs is a useful trait in crop breeding. The pod colours of soybeans primarily include black, brown and tan types, which are controlled by two classical genetic loci, L1 and L2. Most wild soybeans have black pods, which reflect a possible role in adaptation to the natural environment. Here, an improved chromosome segment substitution line (CSSL) population SojaCSSLP3 was established to identify the L1 gene. The segment on the 19th chromosome represented by the SSR marker Satt313 was found to link with locus L1. The region was further delimited three times with increased SSR and InDel markers using a population derived from a heterozygous plant of CSSL124 from SojaCSSLP3. The L1 gene was finally located in a 184.43‐kb region between SSR_19p09 and Indel_19P7. Thirteen putative genes in this region were analysed with qRT‐PCR. The expression level of Glyma19 g27460, which is a member of the SANT superfamily with a MYB DNA‐binding domain, was significantly upregulated in black pods and was recognized to be the most likely candidate for the L1 gene. 相似文献
126.
Nehemia Anthony Mashiringwani Kingstone Mashingaidze Josephine Kangai Klaus Olsen 《Euphytica》1994,76(1-2):33-44
Summary Grain filling rate in wheat (Triticum aestivum L. emend. Thell.) positively influences grain yield under a wide range of conditions. The effective utilization of this trait in breeding depends on an understanding of its genetic control. A study was, therefore, conducted to determine the genetic basis of grain filling rate in six crosses of wheat. Higher order genic interactions and/or linkage were important in the genetic regulation of grain filling rate (GFR) in the majority of crosses. Additive ([d]) and dominance ([h]) gene effects were important in the control of GFR in main ears (ME) and whole plant ears (WPE). Additive and additive × additive epistatic effects were the most important in the genetic control of GFR in last ears (LE). Location effects on genetic effects for GFR were significant (P < 0.05) in all ear types of some crosses except in ME. Genotype × environment interaction effects were important (P < 0.001) in LE and WPE.It was concluded that the inheritance of GFR is complex and is dependent on ear type. Breeding procedures that facilitate the exploitation of non-additive and additive gene effects were recommended for the genetic improvement of grain filling rate of wheat. 相似文献
127.
128.
为探究油菜叶片与角果间光合特性的差异,以双低高油甘蓝型油菜杂交种秦优7号为材料,在不同光照、CO2浓度、温度和一日之内不同时间点等条件下比较了叶片和角果间气体交换参数的差别,结果显示:叶片和角果的气体交换参数随光强、CO2浓度、温度、一日之内时间的变化趋势基本相同。在同等光照条件下,叶片的净光合速率、气孔导度、水分利用效率和气孔限制值均高于角果,而胞间CO2浓度蒸腾速率低于角果;叶片的光饱和点、光补偿点、光呼吸速率明显比角果低,而光量子效率显著高于角果。在同等CO2浓度条件下叶片的净光合速率、水分利用效率、气孔限制值均明显高于角果,而胞间CO2浓度低于角果;叶片的CO2饱和点、CO2补偿点均比角果低,而羧化效率则显著高于角果。叶片进行光合反应的最适温度低于角果,在各自最适和相同温度范围内叶片的净光合速率、气孔导度、蒸腾速率、气孔限制值均明显高于角果,而叶片的胞间CO2浓度、水分利用效率则比角果明显降低。在整个日变化范围内叶片的净光合速率、气孔导度、气孔限制值、水分利用效率明显比角果高,而叶片的胞间CO2浓度、蒸腾速率则明显比角果低。 相似文献
129.
The ability to predict grain protein concentration at harvest (CP) in Swedish malting barley (Hordeum distichum) from observations of soil conditions, sowing day, fertilisation rate, remote sensing at early stem elongation and the temperature sum during grain filling, was tested for two cultivars; Astoria (Secobra, France) and Wikingett (Svalöf-Weibulls, Sweden) in 16 fertilisation trials in southern Sweden, encompassing 3 years (2001–2003). Fertilisation was applied either as a single dose at sowing, or as both a starting application and an application at early stem elongation. The highest total application rate was 160 kg N ha−1 y−1. The soil was analysed for phosphorus, potassium, magnesium and calcium in the layer 0–0.3 m, and mineral N down to 0.6 m. Canopy reflectance observations at BBCH 32 was used to calculate a vegetation index (TCARI(32)) to reflect the canopy (leaf and straw) chlorophyll concentration. Harvested grain CP correlated only marginally with the observed soil variables. It was, however, for a specific cultivar, possible to make a prediction of grain CP based on day of sowing and TCARI(32) with . Part of the sowing day effect might be due to thermal stress during grain filling, as the risk for high temperatures during this phase was higher when sowing was late. This might also explain why the introduction of accumulated temperature during grain filling, into a model already including sowing day and TCARI(32) as independent variables, did not improve the predictability of grain CP. 相似文献
130.
试验研究早晚季不同水稻材料籽粒灌浆特性与耐光氧化反应特性的关系结果表明,耐光氧化反应特性强的适强光生态型水稻品种其达最大灌浆速率的时间较迟,且灌浆生长盛期终止亦迟,各参数在早晚季灌浆结实期保持相对稳定;而不耐光氧化的适弱光生态型品种则反之,其达最大灌浆速率的时间早,且生长盛期结束亦早,各参数在早晚季灌浆结实期稳定性相对较差。 相似文献