Population Dynamics of Sugarcane Woolly Aphid, Ceratovacuna lanigera Zehntner and its Natural Enemies

The study revealed that the peak incidence of sugarcane wooly aphid was observed during fourth week of October (4. 64 pest grade) and then, onwards the pest population gradually decreased during fifth week of January. Micromus activity reached its peak during second week of November (3.31 grubs/leaf) and later population gradually declined till third week of January whereas Dipha aphidivora population reached its peak during fourth week of November (3.06 larvae/leaf). Eupeodes confracter population varied from 0.04 to 1.25 maggots/leaf from second week of August to third week of November with a mean of 0.23 maggots/leaf. The correlation studies revealed that, the pest grade was significant and was positively correlated with evening relative humidity whereas, highly significant negative correlation was observed with maximum temperature. The population of natural enemies viz., Micromus igorotus, D. aphidivora and E. confracter was negatively correlated and significant with maximum temperature.