基于分子标记的入侵陕西草地贪夜蛾种群生物型分析

草地贪夜蛾Spodoptera frugiperda J. E. Smith是一种世界性入侵害虫，为了明确入侵陕西的草地贪夜蛾的种群生物型并了解其发生及扩散规律，本研究对采集自陕西省8个地市180个草地贪夜蛾样本分别进行了基于COI和Tpi分子标记的生物型鉴定。分析发现入侵陕西的草地贪夜蛾84%是水稻型母本与玉米型父本杂交形成的杂合玉米型草地贪夜蛾。COI分子标记的结果显示，样本中水稻型占比为84.44%，玉米型为15.56%；基于Tpi基因片段的结果表明除商洛样本SL-3外，其它样本均为玉米型。值得注意的是，SL-3与非洲特异型序列同源性达100%，此非洲特异单倍型为陕西省内首次、国内第2次出现。本研究为草地贪夜蛾的迁飞扩散规律及早期预警提供了新的理论基础。

Biotype identification of Spodoptera frugiperda populations invaded in Shaanxi Province based on molecular markers

The fall armyworm, Spodoptera frugiperda J. E. Smith is a worldwide invasive pest. In order to clarify the biotypes of the fall armyworm population invaded Shaanxi, and to further understand the population diffusion rules, 180 samples collected from 8 cities in Shaanxi Province were identified based on COI and Tpi molecular markers. The analysis found that about 84% of the fall armyworm samples that invaded Shaanxi were heterozygous corn strain population formed by crossing rice-strain female with corn-strain male parents. The result based on COI gene fragments showed that, the proportion of the samples belonged to rice-strain and corn-strain was 84.44% and 15.56%, respectively. Based on Tpi gene analyses, except for the Shangluo sample SL-3, which belonged to an African-specific haplotype (ASH), all other samples belonged to corn-strain. It was worth noting that the sequence homology between SL-3 and the African-specific haplotype was 100%. This African-specific haplotype was reported for the first time in Shaanxi Province and for the second time in China. This study provided a new theoretical basis for migrating and early warning of S. frugiperda.