www.tjprc.org editor@tjprc.org DIVERSITY OF TWO GENES FROM CHEWING PEST PLUTELLA XYLOSTELLA (L.) POPULATIONS NATIVE TO DIFFERENT GEOGRAPHICAL REGIONS OF KARNATAKA, INDIA B. N. CHAITANYA 1 , R. ASOKAN 2 & T. SITA 3 1, 2 Division of Biotechnology, Indian Institute of Horticultural Research (IIHR), Bangalore, Karnataka, India 3 Head Division of Biotechnology, St. Martin’s College of Engineering, Dollapally, Hyderabad, Telangana, India ABSTRACT Plutella xylostella (L.), the Diamondback Moth (DBM), is a serious pest of cruciferous crops across the world, resulting in crop damage. To evaluate the extent of genetic variation in this species, five populations were collected across Karnataka, India. Two important genes: Ecdysteriod receptor(EcR) and Juvenile hormone epoxidase hydrolase (JHEH) were considered for the same. The former is involved in molting process wherein, the later in reproduction and development. In the present study, we have successfully cloned and sequenced both the genes which resulted in 671 and 798 bp amplicons for both EcR and JHEH gene respectively. Further, on sequence alignment with Bioedit, neither nucleotide variation nor parsimony regions for EcR were reported. In case of JHEH, 56 (7.01 %) nucleotide variations along with 43 parsimony informative sites were chronicled. Further, translating nucleotides, 223 and 266 amino acids were generated respectively. Phylogenetic analysis supported that, populations of DBM under study clustered into a single clade, deciphering perseverance of low genetic variations. The data generated with this study aids in designing a safe and effective management strategy like Ribonucleic acid interference (RNAi). KEYWORDS: Ecdysteriod Receptor, Juvenile Hormone Epoxidase Hydrolase, RNAi, Genetic Diversity Received: Oct 31, 2015; Accepted: Nov 13, 2015; Published: Nov 15, 2015; Paper Id.: IJASRDEC201526 INTRODUCTION Amidst various Lepidopteran insect pests affecting cruciferous crop like cabbage (Brassica oleracea) across the world, the Diamondback Moth (DBM), Plutella xylostella (L.) is paramount (Lim, 1986). Crop damages caused due to DBM infestation may even reach 100 % (Calderon et al., 1986). Global annual management expenditure costs one billion US dollars for DBM alone (Talekar et al., 1993; Capinera, 2001; Ahamad et al., 2012). Present management strategies rely upon the overuse of chemical insecticides including organophosphates, Pyrethroids, avermectins, pyrazoles and oxadiazines, which has resulted in resistance gain (Liu et al., 2012, Zhao et al., 2006, Santos et al., 2011). Also, DBM is the first insect pest that has developed resistance against Bacillus thuringiensis protein toxins at field levels (Sarfraz et al., 2005). At this juncture, a safe, eco-friendly and efficient management strategy is required to control the outburst of this insect pest. Hence, understanding the genome for better knowledge on intraspecific variations could be a resort in confirming population structure and dynamics, their adaptability and response to different selection pressures, which aid in developing efficient biological pest management system like Ribonucleic acid interference (RNAi). Since RNAi exhibits sequence precision in degrading the target mRNA, it can be used as bio-pesticide Original Article International Journal of Agricultural Science and Research (IJASR) ISSN(P): 2250-0057; ISSN(E): 2321-0087 Vol. 5, Issue 6, Dec 2015, 191-198 © TJPRC Pvt. Ltd.