Original Research Article……….. International Journal of Agricultural Invention (online available at www.agriinventionjournal.com) International Journal of Agricultural Invention 2(1): 82-84: June, 2017 ISSN: 2456 – 1797 (P) A note on parasitisation of top borer by Isotima javensis Rohwer (Hymenoptera: Ichneumonidae) *Arun Baitha1, G. M. Tripathi1, Ram Ji Lal1, Rashmi Nigam2 1Division of Crop Protection, ICAR-Indian Institute of Sugarcane Research, Lucknow, U.P., India 2Department of Plant Pathology, J. V. College, Baraut, Baghpat, U.P., India *Corresponding email:
[email protected] ARTICLE INFO ABSTRACT Original Research article Isotima javensis is a solitary ecto parasitoid of the sugarcane top borer, S. exceptalis. It Received on April 15, 2017 attacks the prepupal stage and deposits an egg either on the prepupa or near its vicinity. The Accepted on May 25, 2017 extent of parasitisation was observed 2.12%, 4.28%, 7.14%, 5.88% and 5.23 % in I, II, III, IV and V broods of top borer, respectively. The contribution of mortality of pupae of the Article Authors Arun Baitha, G. M. Tripathi, Ram top borer by parasitisation is high in III and IV broods (Aug-Oct), the time when the brood Ji Lal, Rashmi Nigam infestation remains generally very high. The maximum female ratio (59.72%) was observed Corresponding Author Email in III brood of parasitisation followed by 55.20 % in IV brood. In I and II broods, however
[email protected] more or less equal number of males and females can be observed in the field. Equality in the sex ratio at this time ensures fertilisation of almost all the females for retaining the PUBLICATION INFO vigour and vitality of the species.