Seasonal incidence and Predatory potential of Harmonia dimidiate (Fab.) in relation to Tuberculatum nervatus Chakrabarti and Raychaudhuri

Seasonal incidence of Harmonia dimidiata and its prey aphid, Tuberculatus nervatus were studied on Quercus serrata. The predators and aphids had significant positive correlation (r=0.772 for the year 2004–2005 and r=0.751 for 2005–2006). Abiotic factors such as temperature, relative humidity, total rainfall and sunshine had negative correlation with the predator. The feeding potential of larval stages and adult males and females were evaluated in the laboratory. Among the different larval instars, IV instar larvae were the most voracious (92.13±5.06). The adult male (79.0±4.11) consumed lesser number of aphids than females (86.05±2.27).