SURVEY AND MOLECULAR DETECTION OF FRUIT FLY SPECIES OF GUAVA IN BANGLADESH AND ITS INTEGRATED MANAGEMENT

Abstract

Fruit fly is one of the major insect pests of fruits and vegetables in the world. Fruit flies belong to the family Tephritidae (Order: Diptera) are considered as a very destructive group of insects that cause enormous economic losses in agriculture, especially in a wide variety of fruits, vegetables, and flowers. The identification and management of fruit flies in guava orchard is complex and complicated. The purpose of this study was morphological identification, molecular detection of the most invasive species of fruit flies attacking the vulnerable stage of guava fruit and their management with some promising control options. A survey was conducted at four intensive guava growing regions of Bangladesh (North, Central, South & Hill tracts) to evaluate the extent of infestation of fruit flies, losses due to its infestations, farmer’s interest, and management of fruit fly. It revealed that more than 90 percent farmers were young, and 27 percent landless farmers were involved in guava farming at surveyed locations. However, female farmers involvement was comparatively low. Most popular guava variety was Thai payara and 31 percent area was covered by this promising variety. Other two popular local varieties were viz., Shorupkati and kanchannagar. Almost 20-25 percent yield loss was reported due to fruit fly attack. Fruit fly infestation was observed at ninety seven percent guava orchards in different surveyed locations. Guava farmers mainly used polybag to reduce the fruit fly infestation. Eighty-five percent guava farmer usually practiced trap with pheromone and polybag simultaneously. In morphometric study, examined the species identification of fruit flies infesting guava in Bangladesh. Oriental fruit fly (Bactrocera dorsalis Hendel) was found as the major species which covered seventy eight percent of total fruit fly population and other species were melon fly (Zeugodacus cucurbitae), pumpkin fruit fly (Zeugodacus tau), peach fruit fly (Bactrocera zonata) and. Dacus longnicornis. Data analyses based on five fruit fly taxa revealed moderate performance of this genetic marker COI. BLAST analysis revealed that the observed species showed 98-100% homology with the sequence of Bactrocera dorsalis, Zeugodacus cucurbitae, Zeugodacus tau, Bactrocera zonata and Dacus longnicornis, respectively. Present study investigated the population genetic diversity and structure of 35 populations and haplotype distribution of fruit fly in Bangladesh sampled throughout 12 geographical populations. The population genetic diversity and haplotype distribution study results revealed low genetic diversity of fruit fly of four different species in sampled areas. Significantly negative departures from zero for Tajima’s D neutrality tests values also support population expansions. To find out the effective and sustainable management technique to improve the guava production by reducing the fruit fly infestation, a study was conducted at on-station and Farmers’ field of Savar and Gazipur of Dhaka district and Sher-e-Bangla Agricultural University for testing and rearing the collected sample. Tretment T (Wrapping of twig and fruits with micro nets) showed the higher level of mean number 129.67 of healthy fruit and weight 42.79 g of healthy fruits but the lowest number reduction over control per fruit was obtained from wrapping of twig and fruits with micro nets treated plot. The total fruit yield 34.23 t/ha was significantly higher in the plots treated with the components of T viii

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which was statistically similar to Male Annihilation Technique (MAT).