BIO-ECOLOGY HOST PREFERENCE AND MANAGEMENT OF CUCURBIT FRUIT FLY

Abstract

Thestudy was conducted in the experimental field and laboratory of Sher-e-Bangla Agricultural University (SAU), Sher-e-Bangla Nagar, Dhaka, Bangladesh, during March 2016 to August 2018 to evaluate bio-ecology, host preference and management of cucurbit fruit fly. In Bangladesh, farmers were faced problem in cultivation of cucurbitaceous crops in the field due to cucurbit fruit fly (Bactrocera cucurbitae), the main insect pest of cucurbitaceous crops.The study revealed that, cucurbit fruit fly can attack all types of cucurbitaceous crops. But the infestation become low in kharif season and high in rabi season. Among different types of cucurbitaceous crops cucurbit fruit fly attacks more in bitter gourd and less in sweet gourd. In bio-ecology study, theaverage days for egg incubation (1.7 and 2.7 days), larval period (4.3 and 5.5 days), pupal period (5.9 and 9.8 days),male adult longevity (5.9 and 13.3 days) and female adult longevity (6.7 and 15.8 days) of cucurbit fruit fly were observed at room temperature(±30℃ and ± 85 RH) and laboratory condition(25℃ and 80% RH), respectively.Average ovipositional period of adult female cucurbit fruit flies under room temperature and laboratory condition were 1.4 and 2.9 days, respectively.Average length and breadth of cucurbit fruit flies eggs, larvae, pupa, adult male and female were 1.14 and 0.22,7.9and 2.04,6.2 and 2.38,7.4 and 11.4 and 9.3 and 15.69 mm, respectively.In early, mid and late fruiting stage, the lowest fruit infestation by number and percent fruit infestationby number over control were found in T 2 (6.28 and 76.72%, 12.89 and 83.78% and 14.67 and 83.20%, respectively), using the poison bait trap in the field. In early, mid and late fruiting stage, the lowest fruit infestation by weight and percent fruit infestationby weight over control were found in T 2 (19.30 and 78.73%, 6.18 and 92.48% and 11.98 and 86.63%,

respectively). In early, mid and late fruiting stage, the highest percent edible portion of infested bitter gourd was found in T 2 (66.58%, 75.25% and 75.84%, respectively). The highest number of fruit per plot, single fruit weight, length of single healthy fruit and yield of bitter gourd were found in T 2

(62.33 fruits/plot, 86.04g, 20.66 cm and 17.87 ton/ha, respectively). From the comparative study, poison bait trap (50.00 fruit fly/ trap) was more effective than pheromone trap (19.00 fruit fly/ trap) in terms of capturing adult cucurbit fruit flies throughout the cropping season. The highest benefit cost ratio (BCR) (2.47) was calculated in T 2 , where the total adjusted net return was counted as benefit. In the study of IPM packages for cucurbit fruit fly management, the highest captured fruit flies (36.00 flies) was found in IPM package 1comprised with pheromone trap along with poison bait trap.In early, mid and late fruiting stage, the lowest fruit infestation by number, fruit infestation by weight, edible portion of infested fruit, length of single fruit and girth of single fruit were found in IPM package 1 (22.44%, 11.83%, 90.75%, 21.61 cm and 12.78 cm; 16.66%, 17.37%, 87.67%, 23.22 cm and 14.05 cm and 13.68%, 25.87%, 92.91%, 22.75 cm and 13.24 cm, respectively). The highest number of fruit per plot, single fruit weight and yield of bitter gourd were found in IPM package 1 (76.33 fruits/plot, 50.13g and 12.76 ton/ha, respectively)in the field.