N. Bakthavatsalam ¹, S. P. Singh ¹, P. L. Tandon ¹, M. Chaudhary ¹, S. Preethi ¹

Affiliations
1 Project Directorate of Biological Control (ICAR) P. B. No. 2491, H. A. Farm Post, Bellary Road Hebbal, Bangalore 560 024, Karnataka, IN

Abstract

Chrysoperta carnea (Stephens) is considered as an important predator against Helicoverpa armigera (Hii bner) and other sucking pests. The behavioural response of adult of C. carnea to the volatiles of plants infested by H. armigera was studied under laboratory conditions through electroantennogram and olfactometer. The adults showed good electroantennogram response to volatiles from flowers and bolls of cotton infested by H. armigera. Highest response was noticed to tbe infested bolls than flowers and leaves. In zone resident period studies, the adults spent distinctively more time in the zone 6 (nearest to source) when infested bolls were tested. In dual choice methods, significantly more number of adults reached the synomone arm than the control arm, when infested eotton bolls were tested. The response to infested leaves was very poor.

Keywords

Chrysoperiu carnea, Electroantennogram, Helicoverpa armigera, Infested Cotton, Synomone, Olfactometer.

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N. Bakthavatsalam ¹, S. P. Singh ¹, P. L. Tandon ¹, M. Chaudhary ¹, S. Preethi ¹

Affiliations
1 Project Directorate of Biological Control (ICAR), Post Bag No. 2491, H. A. Farm Post, Bellary Road, Hebbal, Bangalore 560024, Karnataka, IN

Abstract

Hexane wash of gallery and body of Opisina arenosella Walker elicited positive response from the parasitoids namely Goniozus nephantidis (Muesebeck), Brachymeria nephantidis Gahan and Elasmus nephantidis Rohwer, in terms of more number of parasitoids entering the kairomone arm than hexane arm in 'Y' tube olfactometer. Although, numerically, the gallery wash elicited higher response than larval body wash of the host O. arenosella to G. nephantidis, statistically, the treatments were on par. Chemical analysis of kairomonal substances using GCMS revealed the presence of 13-tetradecenal and myristic acid in the gallery wash, in addition to dodecane, pentadecane, hexadecane, heptadecane, eicosane and tricosane. Larval wash showed terpenoids like alpha-terpinene and alpha humulene.

Keywords

Behavioural Responses, Brachymeria nephantidis, Elasmus nephantidis, Goniozus nephantidis, Kairomones, Opisina arenosella.

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