Population variation and polymorphism of the Cotton Pink Bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) using Inter Simple Sequence Repeats (ISSRs) as molecular markers

Abstract

Abstract The most common pest infesting Egyptian cotton plants is the pink bollworm Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae). Intensive insecticide applications required for effective control in production season, resulting insecticide resistance problems. Some investigation ideas were floating for sponsored management. Thus, PCR based examination of pest population DNA tissue differentiation using eight Inter-Simple Sequence Repeats (ISSRs) primers screening for genetic diversity and population differentiation between some Egyptian field populations, based on similarity in the pattern of SDS-page bands. We detected 117 loci with an average population polymorphism of 97.64%. Genetic distance and similarity between groups were calculated and UPMGA phylogenetic tree were constructed. Based on Nei’s distance the specimens statistically grouped into three major clusters and six sub clusters. The average primer efficiency calculated value of PIC = 0.0027, 0.0029 and 0.22, H = 0.326, 0.346 and 0.266, and MI = 0.0669, 0.0768 and 0.04 for Sharkia, Benisuef and Fayoum respectively. Number of identified alleles Na = 1.92, 2.1 and 2.03 and the effective number of alleles Ne = 1.6, 1.93 and 1.78 respectively. Principal component, correspondence analysis and AMOVA results revealed great variance between populations. Moderate level of gene flow was 0.472 to 0.474 and 0.462. Infinite diversity distinguished by Fixation index Fst was ranged from 0.674 to 0.677 across the genotypes. Estimated Shannon’s index (I) procedures of calculations completed as inter-population differences was 6.62 and Nei’s genetic diversity h = 4.7, 4.656 and 4.60. Eveness was 1.09, 1.089 and 1.079 and estimated diversity was 1.24, 1.23 and 1.298, and species richness was 115, 117 and 117 for the same arrangement respectively. All results indicates a high level of genetic variation exists among the three geographical sample populations of the same pest.