High Temperature Effect on Survival of Dysdercus koenigii (Hemiptera: Pyrrhocoridae)

Under natural environmental conditions, insects are highly subjected to thermal stress. Data concerning the effects of high temperature on the survival of Dysdercus koenigii (F.) are scarce. In the present work, the survival rate of all immature stages and adults of D. koenigii exposed to very high temperatures were studied. All stages were exposed to four high temperatures (40, 42.5, 45 and 47.5 degrees C) for time periods ranging from 1 to 420 minutes, depending on the temperature treatment. Insects were then returned to normal temperature conditions. The survival rate of all stages decreased with the increase in the time of exposure at all temperatures examined. The lethal time needed to cause mortality in 50% and 90% of all stages decreased rapidly with the increase in the temperature from 40 to 47.5 degrees C. Based on these results, we concluded that the survival rates of all stages of D. koenigii were significantly affected when they were exposed to high temperature stress.