Use of sex pheromones and light traps for monitoring the population of adult moths of cotton bollworms in Hyderabad, Sindh, Pakistan

Cotton bollworms, spiny bollworm Earias, insulana Boisduval, spotted bollworm, Earias vittella Fabricius, american bollworm, Helicoverpa armigera (Hubner) and pink bollworm, Pectinophora gossypiella (Saunders) are major pest of cotton (Balouch et al., 1990). Two main cotton growing localities Hala and Saeedabad, Hyderabad, Sindh, Pakistan have been selected for study. The light traps and specific sex pheromone traps were used and fixed on one hector area in each locality to monitor the adult population of all species mentioned above. The lures of traps were changed after the interval of 15 days and data were collected weekly. The metrological observations were taken weekly and also took the rainfall data of 2006 and 2007 from Metrology department of Sindh. The adult moths of all species were present in great number through out the cotton season in both localities except H. armigera which was present in noticeable number only in Hala, that was 92 in 2006 and 122 in 2007 while in Saeedabad they were very few in number even they did not reach to double figure, but remaining three species were more than one hundred in Saeedabad, among these pectinophora was in greater number i.e. about 161 adult moths (98% of these were only male, caught by sex pheromones alone). Sex pheromones proved more effective for monitoring the adult moth of all species except H. armigera, i.e. 48 adults were captured by light traps and only 26 were caught by pheromones. P. gossypiella was very attractant to sex pheromones, only 2 % were captured through light trap, but response of Earias species were positive to both techniques, here also pheromones seemed more successful in capturing the adult moth than light trap with little variation in both years. The population of all species was present throughout the cotton season, but high infestation occurs in August to September and reached to its peak in September because of low rain fall in Hala and Saeedabad during both years but the infestation was higher in 2007 than 2006 because of the less rain in 2007 in comparison to 2006.