Genetic Diversity and Population Genetic Structure From Different Host Populations of Spodoptera litura Based on Microsatellite Markers

Abstract

Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) is an agricultural pest with a wide distribution range and many host plants, which can cause serious economic losses. In this study, 157 samples were collected from eight hosts (tobacco, soybean, taro, peanut, chili, sweet potato, corn, and sorrel) in Fuli Town, Fuchuan County, Hezhou City, Guangxi Zhuang Autonomous Region. Seven microsatellite loci were used to analyse the genetic diversity, genetic structure and genetic differentiation of these populations. The results showed that the number of alleles (Na) among the eight populations ranged from 2.43 to 6.14, the average polymorphism information content (PIC) was 0.4574, the mean observed heterozygosity (H_O) and expected heterozygosity (H_E) were 0.4926 and 0.5693, respectively. The genetic diversity of different host populations was high. Bayesian clustering and the NJ phylogenetic tree showed that there were certain genetic structures among different host populations, which could be roughly divided into four genetic groups. The fixed coefficient (F_ST) between populations ranged from 0.010 to 0.208, with low to highly differentiated populations as a whole. This study is helpful to understand the occurrence regularity of Spodoptera litura from different host plants, and provides a theoretical foundation for rational crop layout adjustments and the establishment of an effective integrated control system.