Effect of temperature ramping on the mortality of mango mealy bug, Droschia mangiferae under laboratory conditions

Abstract

Effective alteration of temperature regimes is found prudent to check the insect pest menace as insects are poikilothermic. Effect of high (40-50 °C), moderate (14 °C and18 °C) and low temperature (-4-0 °C) regimes on the survivability of mango mealy bug, Droschia mangiferae was noted in laboratory condition. High temperature regime starts from 40 °C and low temperature from -4 °C respectively. Temperature of both high and low was subsequently increased for 2 °C for each step. Extent of sample insect mortality, in gross, was in consonance with the degree of elevated high temperature and also with the retention time. Even exposure of 10-20 minutes was sufficient to achieve 100% mortality at 480 and 50 °C. However, moderate temperature of 14 °C and 18 °C has very little visible effect on the morbidity of the mealy bug. When the sample was kept at low temperature of 4 °C and 0 °C, for 10 and 20 minutes respectively, 86.7% and 100% died.