Population Dynamics of the Introduced Ladybird Beetle, Curinus coeruleus Mulsant in Relation to its Psyllid Prey Heteropsylla cubana Crawford in Bangalore

Curinus coeruleus Mulsant, a ladybird beetle has been Introduced Into India for the control of the subabul psyllid Heteropsylla cubana Crawford. It has established Itself In the subabul fields of the University or Agricultural Sciences, Bangalore. In the present Investigation, population dynamics of the predator and the prey along with weather parameters were studied. The study revealed the dependence of H. cubana on weather parameters partlcularly rainfall. The population or psyllids gradually declined during summer (May) which was followed by the decline or predator population. Build up of the psyllid population started with the onset of rains, which favoured emergence of new flush of subabul during the third week or May. C. coeruleus populatlon also gradually Increased after the psyllid build up. Partial regression coefficient revealed a strong negative correlation between adult predators and wind speed. Predator adult population had a significant positive relationship with maximum temperature (r = 0.6958), minimum temperature (r = 0.5378)and hours of sunshine (r = 0.6273) but significant negative, relationship with relative humidity (r = -0.7352), psyllid nymphs (r = -0.4250) and wind speed (r = -0.9093). Multiple regression equation was also fitted to predict the predator adult population.