New Horizons in Insect Science Towards Sustainable Pest Management

13

DNA Barcoding for Identification

of Agriculturally Important Insects

S. K. Jalali, Rakshit Ojha and T. Venkatesan

A. K. Chakravarthy (ed.), New Horizons in Insect Science: Towards Sustainable Pest Management,
DOI 10.1007/978-81-322-2089-3_2, © Springer India 2015

S. K. Jalali () · R. Ojha · T. Venkatesan
National Bureau of Agricultural Insect Resources,
Post Bag No. 2491, H. A. Farm Post, Hebbal Bellary
Road, Bangalore, Karnataka 560024 India
e-mail: [email protected]

Abstract

Molecular characterization and DNA barcoding is a taxonomic method

that uses a short genetic marker in an insect DNA to identify a species,

including an unknown species. The DNA barcode method of identifica-

tion includes, for example, identifying insect species from any developing

stage and part; otherwise, identifying insects morphologically generally

depends on adult stage and male genitalia. The utility of DNA barcoding

for these purposes is subject to debate; however, in insects at least, it is

approximately 650 bp of the mitochondrial gene, cytochrome oxidase I

( COX I). The approximate number of described insect species in India is

59,000; however, the number of barcodes generated from India is 4.6 % of

known species, while the corresponding global scenario is about 16 % of

described species; a lot of emphasis is required to catch up with the world

scenario. In order to speed up taxonomic identification, DNA barcoding

is now been considered as an alternative tool for insect biodiversity iden-

tification in India and the world. The present chapter deals with the use

of barcode in the identification of insects belonging to different orders

and families, using the neighbour-joining approach with the bootstrap-

ping method and the Kimura-2 parameter to obtain a clear phylogenetic

signal. In a neighbour-joining tree for all sequences, two clades were ob-

tained: the first cluster consisting of hymenopteran insects and the other

consisting of other orders. This phylogeny also agrees with the traditional

phylogeny of insects. The present results, thus, favour DNA barcoding as

a decisive tool in quick and reliable identification of insects.

Keywords

COX 1 · DNA barcoding · India · Phylogeny

Introduction

Insects are the most abundant of all life on earth

and have evolved into a tremendous range of

different forms. It took nearly 200 years for