Temporal Variation in the Incidence of Legume Pod Borer, Maruca vitrata Geyer (Lepidoptera: Crambidae) on Cowpea and Lablab and its relationship with abiotic factors

Temporal Variation in the Incidence of Legume Pod Borer, Maruca vitrata Geyer (Lepidoptera: Crambidae) on Cowpea and Lablab and its relationship with abiotic factors)

Cowpea and lablab are the two inevitable crops and contribute to significant share in the vegetable production, infested by different insect pests and among them the legume pod borer, Maruca vitrata is a prime menace. The incidence of M. vitrata was recorded on both cowpea (CO 7) and lablab (Rohini) was observed at Department of Pulses, TNAU, Coimbatore during Kharif and Rabi seasons of 2011-12.In cowpea, the mean incidence of 1.09 to 4.54 webbings/ plant was recorded during 34th (IV week of August) and 38th (III week of September) SMWs respectively and lablab suffered with a maximum damage of 3.90 webbings in 42nd SMW (III week of October) while 0.57 webbings during 50th SMW (II week of December). In cowpea, the larval incidence showed a significant positive correlation with minimum RH and rainfall and in lablab, there was a positive correlation recorded with rainfall. About 62.6 and 89.1 per cent variation in larval damage was influenced by weather parameters on cowpea and lablab respectively.. .