Population genetic structure and migration pattern of Nilaparvata lugens (Stål.) (Hemiptera: Delphacidae) populations in India based on mitochondrial COI gene sequences

Despite the economic and ecological impact of the brown planthopper, Nilaparvata lugens infestation associated with rice cultivation in India, studies on its genetic structure are lacking. Hence, the present study was conducted to assess the genetic variability of N. lugens in India. The study evaluated the diversity in N. lugens populations using mitochondrial cytochrome oxidase subunit I gene sequences from India, and compared them with the Bangladesh, China and Japan populations. In all, 47 unique haplotypes were identified and the haplotype number varied from 6 to 18 in the sampled populations. Genetic diversity indices like nucleotide diversity (0.004), average number of nucleotide differences (1.98), haplotype diversity (0.667) and haplotype number (47) of N. lugens populations from India revealed a low level of genetic diversity. A highly significant negative correlation of the demographic history of N. lugens populations along with no significant sum of square deviations indicated possible recent expansion of the brown planthopper in India. A non-significant correlation in isolation pattern by distance results indicated that geographic barriers present in the country are not sufficient for genetic differentiation among N. lugens from different migratory populations. In this study, the genetic diversity of N. lugens populations from India is compared with other Asian populations