Field Evaluation of Steinernematid and Heterorhabditid Nematodes against Plutella Xylostella (L.) on Cauliflower

The efficacy of three entomopathogenic nematodes viz. Steinernema carpocapsae (PDBC), Heterorhabditis indica (PDBC) and S. carpocapsae (JMU) isolates along with insecticides viz. endosulfan 35EC (0.07%) and carbaryl 50WP (0.1%) against diamond back moth, Plutella xylostella L. on cauliflower was evaluated under field conditions. The entomopathogenic nematodes were evaluated each at a dose of 0.5, 1 and 2 billion/ha. Among the nematode treated plots, S. carpocapsae (JMU) was the most effective treatment. The mortality due to S. carpocapsae (JMU) against P. xylostella @2 billion/ha increased from 12.5% 1 day after application to 52.3% 14 days after treatments and 11.6% 1 day after application to 51.6% 14 days after treatments, respectively during 2005–2006 and 2006–2007. Similar trend was observed for other nematode treatments where the mortality increased with time. However, the insecticide treatments showed highest mortality 1 day after treatment application and thereafter the effectiveness of these treatments declined up to 7 days application. Highest mortality was obtained with endosulfan 35EC and carbaryl 50WP after 3 days application.