灰葡萄孢蚕豆分离物的遗传多样性

作者：黄燕，朱振东，段灿星，武小菲，东方阳

影响因子：

刊物名称：中国农业科学

出版年份：2014

卷：47  期：12  页码：2335-2347

文章摘要：

【Objective】Botrytis cinerea is one of the most important pathogens causing chocolate spot, blossom blight and pod rot in broad bean. B. cinerea is a species complex that comprises two cryptic species, Group I and Group II, and exhibits a great morphological and genetic diversity. However, the status of B. cinerea species complex from broad bean as well as their genetic characteristics have been poorly understood. Therefore, this study aims to determine the status and investigate the genetic diversity and genetic differentiation of isolates of B. cinerea complex from broad bean obtained from six different geographic regions. 2336 中 国 农 业 科 学 47 卷 【Method】The B. cinerea isolates were observed for cultural characteristics on potato dextrose agar. Transposons types of the isolates were detected using Flipper- and Boty-specific primers. Group determination of the isolates was analyzed by PCR-RFLP of Bc-hch gene, and their genetic characteristics was analyzed using SSR markers. 【Result】 All the 100 isolates were identified as B. cinerea group II. Three colony types, including mycelial type, sclerotial type and conidial type, were produced, and 76 isolates belonged to sclerotial type. Three transposon genotypes were identified in 92 isolates, which contained Boty-only, Fliper-only and Boty + Fliper genotypes. The most prevalent transposon genotype was Boty-only which was detected in isolates from Chongqing, Sichuan, Gansu and Hebei, while genotype Fliper-only was only found in isolates from Jiangsu. SSR analysis detected 92 multilocus genotypes (MLGs) among the 100 isolates with averaged gene and genotypic diversity of 0.5140 and 0.9982, respectively. Analysis of AMOVA revealed that genetic variation within populations accounted for 86.70% of the total genetic variation. The standardized index of association (rD) was estimated to range from 0.0312 to 0.1261 with the average value of 0.0491. In all comparsions, the values of fixation index (FST) ranged from 0.0085-0.2650 with the average value of 0.1330. All 100 isolates were divided into 10 genetic groups by UPGMA clustering analysis, and most of genetic groups included isolates from different geographic regions. In addition, two genetic groups were inferred in 92 MLGs by Bayesian analysis, and both populations from Chongqing and Sichuan belonged to one group, the population from Qinghai belonged to the other group, while popultions from Jiangsu, Hebei and Gansu were admixture of two genetic groups.【Conclusion】The populations of B. cinerea complex from broad bean made up of only B. cinerea group II. The sclerotial type was main colony morphology. Most of the isolates belonged to transposon genotypes whose distribution existed distinct geographic difference. Great genetic diversity was found in all six populations, and genetic variation mainly presented within populations. Sexual reproduction was the main mode of reproduction. Moderate to large genetic differentiation was detected among most populations.