Studies on Egg Parasitoids of Helopeltis spp. (Hemiptera: Miridae)

Abstract

Survey conducted consecutively for three years from 2010 to 2013 at the Directorate of Cashew Research, Puttur and the Shanthigodu Experimental station, Karnataka, South India determined three species of egg parasitoids; Telenomus sp. (Hymenoptera: Platygastridae), Chetostricha sp. (Hymeoptera : Trichogrammatidae) and Erthymelus helopeltidis (Hym: Myrmaridae) on Helopeltis spp. Telenomus sp. was the predominant species and was recorded throughout the season except during the month of March and April. It showed maximum parasitism during monsoon (June and July) season (range of 6.89-28.21%), exhibiting significant positive correlation with rainfall (r 0.33). The occurrence of Chaetostricha sp. and E. helopeltidis were comparatively lower with a maximum of 1.80 and 2.25 per cent, respectively during the month of December as former showing significant negative correlation with minimum temperature (r -0.63). The mean developmental period of Telenomus sp. was 20.6 ± 1.13 days and male and female longevity were 2.83 ± 0.16 and 4.52 ± 0.11 days, respectively. Five distinct kinds of behaviour were observed; drumming with antennae on the eggs, ovipositor insertion, egg marking, walking and resting.