Population estimates and light trap catches of black cutworm (Agrotis ipsilon Hfn.) on cabbage

The population estimates of Agrotis species (Lepidoptera: Noctuidae) was observed at weekly interval during two consecutive years on cabbage crop. The appearance of Agrotis ipsilon Hufner and Agrotis segetum Schiffer Mueller larval population was noticed from May to October at different localities. The damage was evident just 2–3 days after transplanting. Maximum number of larvae (0.53 larvae and 0.85 larvae/8400 cm³⁾ and maximum damage (29% and 46.61%), was recorded one week after transplanting the crop at Palampur and Matiana locations, respectively. At Palampur and Menjha, the adults of A. ipsilon started appearing in the 15^th standard week. The maximum number (two years pooled data) of adults at Palampur (116.5 adults/trap) and Menjha (97.5 adults/trap) were caught in the 20^th standard week whereas, at Shilaroo (79.5 adults/trap) and Matiana (71.0 adults/trap), they were caught in 23^rd standard weeks. Thereafter, the catches gradually declined at all the selected locations. Further, pest monitoring is discussed in the light of population estimates of A. ipsilon.