$Entomologist, Agricultural Research Station, Sankeshwar- 591 314, Karnataka, India. E mail: sharanu_desh@rediffmail.com
Department of Agricultural Entomology, College of Agriculture, University of Agricultural sciences, Dharwad- 580 005, Karnataka, India.
The study revealed that the incidence of sugarcane woolly aphid, Ceratovacuna lanigera started during fifth week of May and reached its peak during third week of October and afterwards the pest gradually declined with negligible activity during third week of January. Micromus igorotus population initiated from second week of June (0.18 grubs/leaf) and reached its peak during third week of November (3.48 grubs/leaf). Whereas Dipha aphidivora population initiated during first week of June (0.07 larvae/leaf) which reached the peak during fourth week of November (2.93 larvae/leaf) The Eupeodes confracter population varied from 0.03 to 0.92 maggots/leaf from first week of August to second week of December with a mean of 0.17 maggots per leaf. The pest grade was highly significant and positively correlated with morning (r= 0.44**) and evening (r= 0.58**) relative humidity whereas, significant negative correlation was observed with number of rainy days (r= -0.29*). The correlation with weather parameters revealed that, M. igorotus and D. aphidivora were negatively correlated and was non-significant with minimum temperature whereas significantly positively correlated with evening relative humidity. D. aphidivora and E. confracter population were significantly and positively correlated with morning relative humidity.
Population dynamics, Ceratovacuna lanigera, natural enemies and weather parameters
