Confirmatory Evidence of Commercially Exploitable Sex Pheromone Polymorphism in Helicoverpa armigera

The polyphagous nature and high extent of morphological variability in Helicoverpa armigera field populations often lead to a mismatch and inconsistency between actual trap catches and ground truths while using the commercially available combination of 97: 3 Z-11: Hexadecenal (Z11–16: Ald) and Z-9: Hexadecenal (Z9–16: Ald) sex pheromones for trapping male moths. Field trials conducted simultaneously at New Delhi and Sirsa in Haryana in chickpea crop conclusively proved that sex pheromone polymorphism exists in H. armigera aa st variable loadinng sf 1, 5 and 10 mg, the three ratios evaluated (97: 3, 93: 7 and 90: 10 Z-11 and Z- 9 Hexadecenal) gave almost identical catches of male moths. It is concluded that if only one ratio is used in monitoring of the pest it reflects only about 1/3rd of the actual field population. Therefore it is crucial that bouquet of blends be used for effecttve monitoring of the pest.