Study of diversity of culturable gut bacteria in diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)

Abstract

The diamondback moth (DBM) Plutella xylostella (Lepidoptera: Yponomeutidae), a well-known destructive insect pest that infests Bracicaceous (=Cruciferae) crops, like broccoli, brussel sprouts, cauliflower, collards, mustard, rapeseed, radish, and turnip worldwide, has developed resistance to synthetic insecticides. Microbial symbionts provide an diverse range of benefits in insect nutrition, e.g. by providing essential amino acids, digestive enzymes or vitamins and responsible for insecticide resistance. The population of DBM was collected from field of Malligere village, Shivamogga district of the state Karnataka, India. The different bacterial strains were isolated from third instar larvae of DBM and characterized each strain based on morphology and biochemical characterization. Most of the isolates were gram negative bacteria. All the isolates were shown positive results for citrate utilization test and catalase test. The genomic DNA, 16Sr RNA sequencing, PCR were done for identification of isolates at genus level. Six different bacterial isolates were identified such as Enterobacter cloacae, Enterococcus gallinarum, Proteus mirabilis, Providencia sp., Enterobacter hormaechei and Proteus mirabilis. This study aimed to determine the diversity and characterization of gut bacteria of diamondback moth.