Molecular Characterization of Chilli Leaf Curl Virus and Its Vector Management

Abstract

Chilli leaf curl virus is the devastating virus, causing 100% marketable fruit loss. ChiLCV belongs to the genus Begomovirus of the family Geminiviridae and is transmitted by the white fly (Bemisia tabaci). Polymerase chain reaction of Chilli leaf curl virus infecting chilli samples using CLCVF/CLCVR primers amplified the expected product of size nearly 400 bp from chilli-infected samples. PCR products of size 420 bp were obtained, sequenced and assembled. After the nucleotide sequences were translated, 126 amino acid lengths were predicted. The present isolate producing Chilli leaf curl virus formed cluster with other known isolates of ChiLCV , according to the cluster phylogram based on pairwise and multiple sequence alignment of the nucleotide sequence of the CP gene of 3 isolates of ChiLCV and 16 isolates of ToLCJV. Sequence comparisons revealed that ChiLCV has the highest nucleotide sequence identity from ChiLCV -New Delhi [JN663852.1], PePLCBV-Bangladesh [MT636372.2], and ChiLCV -Bareilly [MW528221.1] at about 98.29%, 97.8%, and 96.24%, respectively. Three applications of treatments were applied to chilli plants to manage the ChiLCV vector whitefly (Bemisia tabaci): Eucalyptus oil @ 2%, Bougainvillea leaf extract @ 10%, bioagents (Beauveria bassiana & Lecanicillium lecanii), acetamiprid 20% SP @ 0.02%, diafenthiuron 50% WP @ 0.12%, and a combination of these treatments along with an untreated check. As a consequence of the spraying of acetamiprid 20% SP (2.67 Nos./6 leaves), diafenthiuron 50% WP (2.33 Nos./6 leaves), and L. lecanii (4.33 Nos./6 leaves), the lowest population of whiteflies was observed throughout the crop period. But in case of combination treatment T8 (Bougainvillea leaf extract @ 10% : L. lecanii 2×108 cfu/g @1.5% : Diafenthiuron 50% WP @ 0.12%) showed significant increase in fruit yield as compared to control pot.