Studies on the parasites of Orthaga sp., a pest of Syzygium fruticosum Roxb. at Delhi.

Abstract

In Delhi Orthaga sp. is a serious pest of Syzygium fruticosum, wild 'Jamun'. A severe attack was observed during June '62 in Delhi in I.A.R.I. area. Three parasites viz (i) Phanerotoma n. sp., a primary egg-larval parasite, (ii) Devorgilla sp. near inquinata Morley a larval parasite and (iii) Perilampus microgastris Ferriere a secondary parasite of the first two, were reared. The percentage of parasitism by Phanerotoma sp. ranged from 1.88 to 26.21, and that by Devorgilla sp. from 8.21 to 30.76, while Perilampus attacked 0.38 to 4.95 per cent of the grubs of the two primary parasites. Multiparasitism between Phanerotoma sp. and Devorgilla sp. was about 3.0%. The sex ratio of Devorgilla sp. and Phanerotoma sp. was 2:1 and 1:3, respectively. A detailed account of the immature stages of all the three parasites is given in this paper.