Biology and management of tomato fruit borer, Helicoverpa armigera (Hb.) using African marigold as trap crop

Tomato is one of the major vegetable crop grown throughout the world. its ripe fruit is consumed as fresh vegetable and also in the form of various processed products. in kashmir, it is grown over an area of 1200 hectares with an annual production of 27715 tonnes. tomato fruit borer is one of the limiting factor for the successful cultivation of this crop. Tomato fruit borer (Helicoverpa armigera) is prevalent throughout the Kashmir valley and was found in all the ten locations of the four districts surveyed in 2003 and 2004. Among the locations, pooled data of the two years revealed that fruit damage was highest (19.59%) in Noorbagh of district Srinagar and lowest (1.61%) in Awneera of district Pulwama. Whereas, on an overall mean basis district Anantnag recorded lowest (1.85%) and district Srinagar recorded highest (17.36%) fruit damage. However, hybrids were generally more damaged than local varieties. The effect of marigold which act as a trap crop alongwith various combinations of tomato showed that 3:1 combination recorded lowest fruit damage and larval population but trapped more larvae on trap crop. Thus, the yield was higher than other treatments. However, tomato equivalent yield was 2455714 kg/ha in 2003 and 28399.99 kg/ha in 2004. Efficacy of insecticides viz. imidacloprid (0.03%), deltamethrin (0.01%), fluvalinate (0.01%), fenvalerate (0.03%), chlorpyriphos (0.05%) and endosulfan (0.07%) were sprayed on tomato crop during 2003 and 2004. All these insecticides were superior to control but the imidacloprid at 0.03% concentration was the best treatment recording 28000 kg/ha and 32000 kg/ha in 2003 and 2004, respectively. Different developmental stages of H. armigera observed six larval instars and the total larval period was 17.1 ± 0.21 days, pupal period 8.6 ± 0.22 days and the duration for total life span for male was 30.2 ± 0.23 days and for female it was 38.7 ± 0.24 days. It was observed that 3:1 combination proved to be the best treatment without using any type of insecticide and among the insecticides, imidacloprid (0.03%) was the best treatment