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951.
Three double low (erucic acid and glucosinolates) self-incompatible lines and 22 varieties from different origins were selected to produce 66 hybrids according to a NC II mating design. Field experiments for identification of hybrid performance and heterosis were conducted in two successive rapeseed growing seasons in Wuhan, China. After heterosis identifications, SI-1300 and Eagle were chosen to construct an F2 segregating population. One hundred and eighty four F2:3 lines were planted at Wuhan and Jingmen to test yield traits. F2 plants and the 25 parents were analyzed using simultaneously AFLP (amplified fragment length polymorphism) and SSR (simple sequence repeat) markers. A total of 270 and 718 polymorphic loci were detected in the F2 population and among the 25 parental lines, respectively. Of the 718 polymorphic loci, 178 were significantly correlated to yield traits. With the use of one-way ANOVA, 84 common QTLs were detected for 12 traits at two trial locations. Although the genetic distances based on general/specific heterozygosities and single-locus QTLs showed significant correlations with hybrid performance and heterosis for some yield traits, the determination coefficients were low. The results suggested that neither heterozygosities nor QTLs for yield traits were suitable to predict hybrid performance and heterosis in Brassica napus. 相似文献
952.
从麻竹(Dendrocalamus latiflorus)叶中分离得到四个黄酮类化合物。经性质和光谱(UV,IR,MS,1HNMR,13CNMR等)法鉴定其结构,分别为牡荆苷(?),芦丁(II),山奈酚-3-O-β-D-芸香糖苷(III),山奈酚-3-O-β-D-葡萄糖基(1-2)-α-L-鼠李糖苷(IV)。四种化合物均为首次从该植物中得到。 相似文献
953.
954.
核不育亚麻不育株与可育株同工酶分析 总被引:4,自引:0,他引:4
本文采用聚丙烯酰胺凝胶电泳法,对核不育亚麻不育株和可育株分别进行了过氧化物酶同工酶、酯酶同工酶的比较研究,找到了过氧化物酶同工酶在不育株和可育株整个营养生长时期的变化规律;同时发现了不育株和可育株雄蕊的两种同工酶酶谱存在着显著差异。也就是说,雄性不育基因调控了同工酶的形成和差异,进而影响了相应组织的生长 相似文献
955.
956.
WANG Jian-ping QIN Hai-feng WEN Xiao-ming Institute of Horticulture Inner Mongolia Academy of Agriculture husbandly Sciences Huhhot China 《华北农学报》2006,(Z3)
近年来转基因食品在世界范围内发展迅速,人们对转基因食品的安全性也日益关注。文章介绍了转基因食品的发展现状、转基因食品安全性研究的内容、评价原则。 相似文献
957.
958.
大花蕙兰的种子在1/2 MS培养基上萌发并生长到直径0.5~1.0 mm后,转接到新的培养基继续生长并进行茎叶和根的分化。试验选择MS、1/2 MS、KC、VW四种培养基,各添加NAA 1 mg/L,pH值5,2。每个培养皿接种原球茎20个,培养温度25℃,光照强度3000 lx。经过90d的培养,期间每隔15d进行称重,计算出原球茎生长过程中质量的增加。结果证明萌发后的原球茎在1/2 MS培养基上生长最佳,其次为MS和KC,VW培养基不适宜原球茎的继续生长。 相似文献
959.
Use of Molecular Markers in Breeding for Oligogenic Disease Resistance 总被引:12,自引:0,他引:12
A. E. Melchinger 《Plant Breeding》1990,104(1):1-19
960.
Effective cumulative temperature (ECT) after heading would be a more reasonable parameter for seed sampling of pre-harvest sprouting/seed dormancy (SD) tests in segregating populations than the days after flowering. SD is an important agronomic trait associated with grain yielding, eating quality and seed quality. To identify genomic regions affecting SD at different grain-filling temperatures, and to further examine the association between SD and ECT during grain-filling, 127 double haploid (DH) lines derived from a cross between ZYQ8 (indica)/JX17 (japonica) by anther culture were analyzed. The quantitative trait loci (QTLs) and their digenic epistasis for SD were identified using a molecular linkage map of this population. A total of four putative QTLs for SD (qSD-3, qSD-5, 6 and 11) were detected on chromosomes 3, 5, 6 and 11, together explaining 41.4% of the phenotypic variation. Nine pairs of digenic epistatic loci were associated with SD on all but chromosome 9, and their contributions to phenotypic variation varied from 2.87%–8.73%. The SD QTL on chromosome 3 was identical to the QTLs found in other mapping populations with different genetic backgrounds, which could be a desirable candidate for gene cloning and marker-assisted selection in rice breeding. 相似文献