辣椒新品种“鄂椒香帅”的选育

"鄂椒香帅"是以BL8为母本,CA1324-4为父本育成的鲜食长线椒辣椒杂交一代品种。该品种植株生长势较强,株高55 cm,开展度52 cm,叶片绿色,卵圆形,少茸毛,单叶互生,分枝性较强且分枝处有紫色斑块,始花节位8~9节,花冠白色,花萼平展;坐果力较强,果实长28~32 cm,果实横径1.3 cm,果肉厚0.2 cm,果实长羊角形,椒条顺直,果面较光滑,三心室,单果质量约26 g,果色绿色,肉质脆,味辣,适合鲜食。抗疮痂病、中抗黄瓜花叶病毒病(CMV),挂果性好,产量高;适合长江流域地区春夏季露地和高山栽培。     

Genetic diversity and classification of Nelumbo germplasm of different origins by RAPD and ISSR analysis

In this study, RAPD and ISSR markers were used to investigate the genetic diversity and genetic relationships among different germplasm of Nelumbo including 70 Chinese ornamental cultivars, 7 wild Thai genotypes, 2 Nelumbo lutea genotypes and 8 hybrids of Nelumbo nucifera and N. lutea. High genetic diversities of 96.4% and 91.2% respectively were detected in the Nelumbo accessions using RAPD and ISSR markers. A dendrogram based on both RAPD and ISSR clustering data indicated that: (1) the genotypes of N. nucifera and N. lutea from different geographical origins were clustered into different groups. This indicated significant genetic differentiation attributed to extensive periods of geographical isolation and lack of gene exchange; (2) the Thai wild genotypes were separated from Chinese genotypes. This indicated genetic divergence between germplasm from Southeast Asia and that from China. Geographical location appears to have affected genetic diversity due to adaptation of the plants to the different environments. A new Southeastern Asia Lotus category is suggested as an addition to the current lotus cultivars classification system; (3) data on three morphological traits (namely: plant size, petal shape and flower color), showed that only the data on plant size was consistent with the dendrogram constructed from molecular data. This finding suggests that using data on genetic relationships in combination with morphological characteristics would serve to improve the classification system of lotus cultivars currently in use. The finding of previously unknown germplasm in this study indicated the potential of RAPD and ISSR techniques in identifying and managing lotus resources. Both marker techniques are potentially useful in improving the current strategies in breeding and germplasm conservation to enhance the ornamental and economic value of lotus.     

辣椒热激蛋白HSP90家族基因鉴定及分析

借助生物信息学工具对辣椒热激蛋白HSP90家族基因进行鉴定，并分析其理化性质、结构特征、系统进化关系以及在各组织器官和高温胁迫下的表达模式。结果表明，辣椒基因组中含有7个HSP90家族基因，分布于5条染色体上，内含子数2 ~ 19不等，含有5个保守基序；系统进化关系分析显示辣椒7个HSP90家族基因分为3组；亚细胞定位结果显示辣椒HSP90蛋白定位于细胞质与内质网中；基于已发表的转录组数据进行组织表达分析，HSP90在不同组织中的表达模式不同；高温处理可不同程度地激活HSP90的表达。     

EXOGENOUS APPLICATION OF POTASSIUM NITRATE TO ALLEVIATE SALT STRESS IN RICE SEEDLINGS

□ Overall growth characteristics of many plant species cultivated in soil affected by salinity could be alleviated by the application of potassium nitrate (KNO₃) to the soil. The aim of this research was to investigate salt-tolerance in a salt-sensitive rice cultivar, ‘Pathumthani 1’ (PT1), in response to the exogenous application of 11.8 mM KNO₃, in comparison to ‘Homjan’ (HJ), a salt tolerant cultivar. Water potential (ψ_w) in both the roots and leaves of PT1 seedlings under salt stress dropped significantly, while it was maintained in PT1 pretreated with KNO₃, and similarly in HJ. The reduction of leaf water potential was positively related to total chlorophyll degradation, leading to diminished chlorophyll fluorescence, directly affecting growth in plants exposed to salt stress. In salt-sensitive PT1, the application of 11.8 mM KNO₃ improved salt-tolerance via the conservation of water use efficiency, the maintenance of photosynthetic pigments, enhancement of chlorophyll a fluorescence, and stimulation of growth characters.