Prediction of heterosis using QTLs for yield traits in rapeseed (Brassica napus L.)

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 F_2:3 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.     

Cmponent Study on Flavonoids From Leaves of Dendrocalamus Latiflorus

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。     

镉处理对绿豆种子萌发及蛋白质含量的影响

采用室内试验方法，研究了不同浓度的Cd^2＋溶液对绿豆种子萌发及蛋白质含量的影响。结果表明，当Cd^2＋溶液浓度低于20mg/L时，种子的发芽率不受Cd^2＋溶液浓度的影响；当Cd^2＋溶液浓度低于10mg／L时，种子的发芽指数不受Cd^2＋溶液浓度的影响；与对照相比。种子的活力指数与发芽势随着Cd^2＋浓度的增加而下降。种子内的蛋白质含量随着Cd^2＋溶液浓度的提高而升高，而蛋白酶活性和自由氨基酸的含量均下降。     

核不育亚麻不育株与可育株同工酶分析

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     

TTCH定量测定辣椒种子的活力及活力丧失原因的探讨

本文以辣椒种子为材料,测定了不同贮存年限的辣椒种子发芽率,用TTCH测定了其活力,结果表明活力指标与发芽率相关极显著,华椒1号的相关系数达0.8912,华椒17号的相关系数达0.9277。实验表明辣椒种子活力下降的内在因素是膜的破坏、活性物质减少及毒素积累等因素引起的。     

转基因食品安全性问题的研究现状

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。     

适合RAPD分析的三种玉米基因组DNA提取方法比较

本文通过对3种玉米基因组DNA提取方法的比较得出，DNA提取时采用一次氯仿／异戊醇抽提方法，得到的DNA质和量都较为理想，并且能够达到RAPD实验的要求。     

大花蕙兰种子萌发的原球茎在不同培养基上的生长效研究

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。     

QTL analysis of seed dormancy in rice (Oryza sativa L.)

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.