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71.
陆地棉MADS-box基因GhMADS13的功能分析   总被引:1,自引:0,他引:1  
为了研究GhMADS13的功能,利用NCBI上提交的序列设计引物进行PCR扩增,扩增序列与提交序列的ORF (Open reading frame)的一致性为100%.qRT-PCR结果表明:棉花的各个组织中,GhMADS13在花中的表达量最高,是表达量低的根的几百倍;花器官中GhMADS13在萼片、花瓣、雄蕊、心皮和胚珠中都有表达,表达量虽有差异,但差异不大,其在胚珠中的表达量最高.将GhMADS13插入到pBI121载体上,构建了植物超表达载体.通过浸花法转化拟南芥,获得了2个转基因株系,分子检测和表型数据统计的结果表明GhMADS13的转录水平越高植株越矮小,角果的长度越短,种子的数目越少.根据GhMA DS13的qRT-PCR结果和异位表达分析,推测GhMADS13主要抑制胚珠的发育.  相似文献   
72.
棉花品种遗传纯度的SSR分子标记鉴定技术研究   总被引:7,自引:2,他引:5  
为建立适合于SSR标记的棉花品种纯度鉴定方法,利用78个SSR标记对12个棉花常规品种进行标记基因型分析.通过比较不同品种不同单株标记基因型,发现棉花品种的非纯SSR位点存在3种主要类型.通过综合分析非纯SSR位点率和异型单株率对品种遗传纯度的影响,建立了利用SSR标记在分子水平上鉴定棉花品种纯度的方法.利用该方法鉴定的12个棉花品种中有3个品种(C5、C9和Cll)的遗传纯度在98%以上,非纯SSR位点和异型株均较高的2个品种(C3和C6)遗传纯度分别为67.31%和31.79%,该方法弥补了以往分子纯度计算方法中只考虑单株混杂、不考虑SSR位点混杂的缺陷,可比较客观地反映品种的遗传纯度状况.  相似文献   
73.
A large number of regional crop trials have demonstrated the ubiquitous existence of genotype × environment interactions (G×E), which make it complicated to select superior cultivars and identify the ideal testing sites. The GGE (genotype main effect plus genotype × environment interaction) biplot is the most powerful statistical and graphical displaying tool available for regional crop trial dataset analysis. The objective of the present study was to demonstrate the effectiveness of the biplot in evaluating the high and stable yields of candidate cultivars simultaneously, and in delineating the most adaptive planting region, analyzing trial location discrimination ability and representativeness, and identifying the ideal cultivar and trial locations. The lint cotton yield dataset with nine experimental genotypes and 17 test locations (three replicates in each) was collected from the national cotton regional trial in the Yangtze River Valley (YaRV) in 2012. The results showed that: (1) the effects of genotype (G), environment (E), and genotype × environment interaction (G×E) were significant (P < 0.01) for lint cotton yield. Differences among environments accounted for 78.7% of the treatment total variation in the sum of squares, whereas the genotype main effect accounted for 8.7%, and the genotype × environment interaction accounted for 12.6%. (2) The “ideal cultivar” and “ideal location” view of the HA-GGE biplot identified Zhongcj408 (G2) and Nannon12 (G9) as the best ideal genotypes; Cixi in Zhejiang Province and Jiangling in Hubei Province were the most ideal locations.(3) The “which-won-where” view of the biplot outlined the adaptive planting region for each experimental cultivar. (4) The “similarity among locations” view clustered the trial locations into four groups, among of which the two outlier locations, Shehong (SH) and Chengdu (QBJ), located in Shichuan Basin in the upper reaches of YaRV, were clustered in one group, whereas the Nanyang (NY) of Henan Province at the northern edge of YaRV was singled out as a sole group. Such location clustering results implied an apparent association with the geographical environment.  相似文献   
74.
《Plant Production Science》2013,16(3):224-228
Abstract

Abstract : Cotton (Gossypium hirsutum L.) and soybean (Glycine max (L.) Merr.) cultivars were grown under arid (Urumqi, Xinjiang, China) and humid (Matsudo, Chiba, Japan) conditions to analyze their abilities to adapt to arid conditions in terms of transpiration, leaf movement and leaf temperature. Under the arid condition, the leaf temperature of the cotton cultivars was higher than that of the soybean cultivar and the air temperature. There was no significant difference in leaf temperature among the cotton and soybean cultivars under the humid condition. The flow rate of stem sap in the cotton cultivars under the arid condition was always higher than that in the soybean cultivar, and was largely affected by vapor pressure deficit (VPD). Under the humid condition, however, the flow rates of stem sap were lower in the cotton cultivars than in the soybean cultivars. These results indicate that cotton can avoid heat stress by the high transpiring ability possibly supported by well-developed root systems, which leads to higher drought resistance under the arid condition. Soybean would adapt to arid conditions by the combination of paraheliotropic leaf movement and reduced transpiration.  相似文献   
75.
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77.
陆地棉原生质体培养与植株再生   总被引:11,自引:0,他引:11  
以陆地棉品种“珂字201”为材料,比较了IAA+KT和2,4-D+KT在愈伤诱导和悬浮培养中的效应,结果表明:愈伤组织诱导中,IAA和2,4-D表现为正效应,且2,4-D的效应强于IAA;KT表现为负效应;胚性愈人务悬浮培养中;3种激素都表现出负效应。以胚性细胞悬浮系了原生质体的分离和培养试验,分离原生质体的最佳酶组合为纤维素酶3%+果胶酶1.5%,原生质体培养的最佳激素为IAA0.5mg/L+K  相似文献   
78.
基因型对陆地棉花药离体培养反应的影响   总被引:3,自引:0,他引:3  
对27种棉花基因型的花药在离体培养中的反应进行了比较,结果表明:所有的基因型在合适的培养条件下均能高频率地形成愈伤组织,但不同基因型间愈伤组织诱导率和诱导量不同;再生植株的花药比原始亲本的花药易诱导出愈伤组织;品种间杂种表现出部分优势,但不明显。本试验中,仅鲁棉6号和Siokra1-3两个品种诱导获得了胚性愈伤组织、胚状体和再生植株,且二者之间也存在着差别。从基因型在棉花花药培养中的效应、外界调控对棉花不同基因型花药培养效果的影响、棉花花药培养与体细胞培养基因型差异的比较等三个方面进行了讨论,提出了棉花花药培养愈伤组织诱导和植株再生是受两套遗传基因控制的遗传性状,并提出了棉花组织培养植株再生的阈值问题  相似文献   
79.
X. F. Zhu    X. D. Wang    J. Sun  T. Z. Zhang  J. J. Pan 《Plant Breeding》1998,117(6):549-552
Paired A- and B-lines, cytoplasmic male-sterile (CMS)-lines and main-tainer lines, respectively, were crossed with R-lines (restorer) to produce A × R, R × B and B × R hybrids, which were used in 1993 and 1996 to predict the performance of three lypes of CMS cotton lines available in China. A significant difference in yield and yield components was revealed between paired A × R and B × R hybrids. This difference was greatly influenced by both CMS cytoplasm and the interaction between cytoplasm and nuclear genotypes. It is suggested that there are detrimental effects of CMS cytoplasm on yield and yield components. General combining ability of near-isogenic CMS lines was also affected by this negative effect. The detrimental effect was closely related to an increased number of immature seeds per boll, which might be caused by partial female sterility associated with CMS cytoplasm. The possibility of developing specific combinations of CMS Upland × Upland restorer hybrids that express enough heterosis for yield to overcome the detrimental effect of the CMS cytoplasm is discussed.  相似文献   
80.
陆地棉品种与陆地棉族系种质系间杂种优势及其组成分析   总被引:7,自引:1,他引:6  
游俊  刘金兰 《作物学报》1998,24(6):834-839
采用NCⅡ遗传交配设计,选用3个陆地棉常规品种和5个陆地棉族系种质系材料杂交,杂种F1代产量和纤维品质优势表现明显。通径分析结果表明,提高铃重,单株铃数的中亲优势,适当降低单铃种子数和株高的优势。在其它性状适宜的情况下,可以显著地提高皮棉产量的中亲优势。各个优势组合在产量优势来源上有差异。种质系材料在杂种优势利用上具有很大潜力。  相似文献   
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