Tobacco cultivar/line Jingyehuang, named JYH, and Beinhart1000-1, named Beinhart, have shown effective resistance to brown spot disease. In this study, populations of P1, P2, F1, and F2 were generated as experimental materials from two crosses between the two cultivars and susceptible cultivar NC82. The joint segregation analysis method of mixed major gene plus polygene genetic model was used to investigate the inheritance of resistance to brown spot disease in tobacco. The results showed that the inheritances of both JYH and Beinhart fitted to a mix genetic model of two major genes with additive-complete dominance effects plus poly-genes with additive-dominance effects (E-5 model). For high resistance material JYH, the additive effect of the first major gene was larger than the second one. For high resistance material Beinhart, the additive effect of two major genes was equal. Heritability of the major genes was 64.72% in JYH×NC82, and 63.88% in Beinhart×NC82 in F2, indicating that resistances to brown spot disease in tobacco cultivars JYH and Beinhart were mainly controlled by major genes.

为发掘与烟草化学成分紧密关联的SSR位点,以24个烟草品种为材料,按照烟草行业标准规定的方法检测其中总糖、还原糖、总氮、总生物碱、钾含量、氯含量;使用109对SSR引物对24个烟草品种的基因组进行扩增,聚丙烯酰胺凝胶电泳检测,共检测到104个多态性位点;与烟草中6个化学指标数据进行关联分析,在P≤0.01的显著性水平下,共发现8个SSR位点与除总生物碱以外的5个指标极显著相关,发掘到的关联位点主要集中在8号连锁群上,3个SSR位点同时关联到总氮与糖类.

Flavonoid are important aroma precursors, which are controlled by many regulatory genes. Chalcone synthase gene (CHS), as one of the key gene of the flavonoid pathway, plays an important role in the synthesis of aroma precursors. The function missing or mutation of the CHS would affect the aroma formation. To explore the effects of CHS down regulatory expression and to provide technical information for breeding high aroma tobacco, we constructed the RNAi expression vectors by Gateway technology. Then the vectors were transformed into the‘Dabaijin599’ by Agrobacterium-mediated method to form basis for further study in the aroma of CHS gene. Thirty of tobacco plants were obtained and 24 of them were identified as transgenic plants.