中国重要农业害虫韭菜迟眼蕈蚊多态性EST-SSR标记的开发

【背景】韭菜迟眼蕈蚊是我国重要的农业害虫,然而它的遗传资源有限。本研究旨在开发韭菜迟眼蕈蚊EST-SSR标记,为研究不同地区的韭菜迟眼蕈蚊种群结构和遗传多样性奠定基础。【方法】从韭菜迟眼蕈蚊的表达序列标签(EST序列)中设计16对简单重复序列(SSR)引物,进一步筛选出9对具有多态性的SSR引物。【结果】从42095条unigene中确定了3383个SSR位点。利用查找到的SSR位点共设计出16对引物,进一步检测筛选发现9对引物具有多态性,引物的每个位点平均有3.33个等位基因。利用9对引物对30头韭菜迟眼蕈蚊进行检测,共获得30个等位基因,观测杂合度和期望杂合度的范围分别为0.0000~0.6875和0.0370~0.6877;其中,9个位点中有5个位点显著偏离Hardy-Weinberg平衡。【结论与意义】本研究成功从迟眼蕈蚊EST序列中筛选出9个具有多态性的微卫星位点,这为进一步分析该害虫种群的遗传结构和遗传多样性奠定了基础。

Development of polymorphic EST-SSR markers from Bradysia odoriphaga (Diptera: Sciaridae), a serious agricultural pest in China

Background] The chive gnat, Bradysia odoriphaga Yang and Zhang (Diptera:Sciaridae), is a severe agricultural pest in China. Knowledge on the biology, dispersal, and other important aspects of this insect is limited. Filling this knowledge gap is hampered by the lack of suitable the genetic markers. The aim of the present study was to develop simple sequence repeat (SSR) markers from expressed sequence tags (ESTs) that can be used for genetic diversity and structure analysis of B. odoriphaga.Method] The SSRs primers were designed and tested based on the ESTs of B. odoriphaga obtained in this study.Result] A total of 3383 SSRs were identified from 42095 unigenes. Sixteen pairs of primers were designed and tested in 30 B. odoriphaga larvae, of which nine primer pairs produced polymorphic amplicons. Thirty alleles were identified from 30 larvae using the nine markers, with an av-erage of 3.33 alleles per locus (ranged from 3 to 4). The range of observed and expected heterozygosity was 0.0000~0.6875 and 0.0370~0.6877, respectively. Five of the nine loci exhibited significant departure from Hardy-Weinberg equilibrium.Conclusion and significance] The nine polymorphic microsatellite loci developed in this study can be used to research the genetic diversity and structure of B. odoriphaga populations.