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Abstract
Aim:
To identify the volatile organic compounds (VOCs) from wild and cultivated
jute species imparting varying degree of non-preference for oviposition and
feeding to jute hairy caterpillar, S. obliqua Walker.
Methodology: Different host species of S. obliqua viz.,
Corchorus olitorius, C. aestuans, C. pseudo-olitorius, C. fascicularis, C.
tridens and C. trilocularis were used to find out the feeding and
oviposition preference of S. obliqua. Headspace volatiles were collected from
different genotypes of jute and the chemical analysis was done with Gas
chromatography - Mass Spectrometry (GC-MS).
Results: The chemical
compounds of VOCs responsible for causing non-preference mechanism of host
plant selection to S. obliqua. The chemical complexity and chemistry
of volatiles from cultivated and wild jute species indicated significant
variation. The VOCs identified in C. aestuans was comparatively more
than cultivated species and were different from other cultivated and wild
species of jute. Very low preference index for larval feeding and oviposition
preference of S. obliqua was due to the possible deterrent effect of
volatile organic compounds.
Interpretation: The GC-MS
analysis of VOCs from C. aestuans (WCIN-179) indicated strong
repellent action on S. obliqua that makes it resistant due to
non-preference mechanism resulting in less preference for egg laying and feeding.
The uniqueness and novelty of C. aestuans confirmed on the basis of
very unique VOCs profile which makes it resistant against S. obliqua
through multiple mechanisms, i.e., antibiosis and non-preference
recording least suitable for egg laying, biology and growth of insects.
Key words: GC-MS, Hairy
caterpillar, Jute, Oviposition, Volatile Organic Compounds
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