Phenology and Parasitization Behaviour of Telenomus cuspis (Hymenoptera: Platygastridae) an Egg Parasitoid of Helopeltis antonii (Hemiptera: Miridae) in Cashew

Abstract

Population dynamics of the egg parasitoids of the tea mosquito bug, Helopeltis antonii was investigated between June 2010 and May 2013. Three species of egg parasitoids attacked Helopeltis spp. in cashew orchards viz. Telenomus cuspis Rajmohana and Srikumar, Chaetostricha sp. and Erthymelus helopeltidis Gahan. T. cuspis was the most abundant species and was recorded throughout the year with the exception of March and April. It showed the maximum parasitism rate during the monsoon (28.21 %), exhibiting a significant and positive correlation with rainfall (r = 0.33). The occurrence of Chaetostricha sp. and E. helopeltidis was occasional (1.80 and 2.25 %, respectively) during December, showing a significant and negative correlation with the minimum temperature (r = −0.63). The development time of T. cuspis was 20.6 ± 1.13 days. Longevity was significantly shorter for male (2.83 ± 0.16 days) than for female (4.52 ± 0.11 days). Elements of parasitoid foraging behaviour such as antennal drumming, ovipositor insertion, egg marking, walking and resting were also observed. The level of parasitism provided by T. cuspis suggests a good potential for biological control against Helopeltis spp.