Population dynamics of the dusky cotton bugOxycarenus laetus Kirby in relation to climatic variation (Heteroptera: Lygaeidae)
The population trend of the dusky cotton bug,Oxycarenus laetus Kirby is studied for two years, on three principal hosts namelyAbutilon indicum, Sida acuta andThespesia populnea in relation to climatic variation. Population density varies significantly over the months as shown from the analysis of variance thereby indicating that the population build up is favoured by certain climatic factors. Regression analysis shows that variables such as temperature and relative humidity have very significant effect on the growth of the population. Peak population is recorded during hotter months March–July; the population is at its low ebb during colder winter months November–January. High temperature (35°C–40°C) and moderately high humidity (45–60%) seem to be the favoured climate for rapid growth of the population, whereas very high humidity adversely influence the population as indicated by the negative regression values obtained consistently in both years.