International Journal of Tropical Insect Science (2018) 38, 145-158

Fazil Hasan, M. Shafiq Ansari, Mukesh K. Dhillon, Mohammad Muslim, Amarpal Singh Bhadauriya, Aditya Kumar Tanwar and Salman Ahmad (2018)
Diapause regulation in Zygogramma bicolorata (Coleoptera: Chrysomelidae), a biocontrol agent of Parthenium hysterophorus
International Journal of Tropical Insect Science 38 (2), 145-158
Abstract: Zygogramma bicolorata Pallister is a potential biocontrol agent of Parthenium hysterophorus L. (Asteraceae). This study was carried out to understand the effect of abiotic (temperature and moisture) and biotic factors (age and reproductive status) on the induction and termination of diapause in Z. bicolorata. We also evaluated the effect of diapause on longevity and fecundity of Z. bicolorata. In Z. bicolorata the induction of diapause occurred between the months of July and December. No diapause was observed in May and June, which coincided with the commencement of the monsoon rains. The percentage of diapause induction in Z. bicolorata was found to increase from one generation to another as well as with the age of adults. Diapause significantly increased the fecundity of females as compared to the fecundity in pre-diapause conditions. Soil moisture (80% RH) played an important role in providing the conditions for initiation and termination of diapause. Similarly, 18.4 and 12.5% of diapause adults resumed their activity in 6 and 5 days when exposed to temperatures of 40° and 45° C for 2 h every day, respectively. Exposure of adults to low temperatures, i.e. 5° and 10° C induced 94.3 and 92.5% diapause, respectively, with no adult mortality. Thus, our findings reveal suitable conditions for preventing and inducing diapause in Z. bicolorata, which is of great importance in the suppression of P. hysterophorus. We discuss the implications of these findings in the control of P. hysterophorus.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: English)
Link to article at publishers website
Database assignments for author(s): Mukesh K. Dhillon, M. Shafiq Ansari

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Parthenium hysterophorus (weed)		India
Zygogramma bicolorata (weed bioagent)	Parthenium hysterophorus (weed)		India