http://localhost:8080/handle/123456789/3772 2026-04-18T16:16:52Z http://localhost:8080/handle/123456789/5252 DEVELOPMENT OF AN INTEGRATED MANAGEMENT APPROACH AGAINST MAJOR ARTHROPOD PESTS OF CAPSICUM MD. ZAKARIA Capsicum cultivation plays a crucial role in the agricultural economy of Bangladesh, but the infestation of major insect pests poses significant challenges to its productivity and sustainability. The primary objective of this study was to develop an effective Integrated Pest Management (IPM) package to combat major insect pests affecting capsicum. The study conducted between 2018 and 2022 encompassed four experiments. Initially, a field survey was conducted in Rajbari, Bogura, Sylhet, Kishoreganj and Manikganj districts in Bangladesh, focusing on intensive capsicum cultivation areas. Results showed that 36% of the surveyed areas experienced low pest infestation, 22.4% faced moderate infestation, and only 4.8% had severe infestation. Capsicum growers utilized diverse control measures, with 71.14% employing a combination of chemical and other methods, while a mere 5.77% practiced fully non-chemical approaches to combat pests such as thrips, aphids, fruit borers, mites, and whiteflies. The highest healthy fruit yield recorded was 24.38 tons ha -1 , and the maximum benefit-cost ratio (3.12) was observed in Capsicum Grower’s Practice (CGP)-8 (Combination of chemicals, bio-pesticide, mechanical, cultural and mulching materials). The second experiment aimed to screen potential capsicum varieties for their resistance to pests by employing different mulching materials. Among the four varieties tested, California Wonder demonstrated the best resistance to pests and yielded higher produce. Combining California Wonder variety with black polythene mulching showed superior performance in controlling pest infestations at various growth stages, leading to improved yields compared to other varieties and combinations. In the third experiment, eight treatments were tested, focusing on the entire growth period, infestation levels of whiteflies, aphids, thrips, fruit borers, and mites, healthy and infested leaves and fruits per plant, and yield-contributing characteristics. Treatment T 3 , involving Imidacloprid 20% SL @ 0.5 ml/L of water with a 7-day interval exhibited the best results. The lowest performance was observed in the controlled plots (T 8 ), followed by T 7 (field sanitation + pheromone trap). A comparison between two fields indicated that the farmer's field in Hemayetpur village, Singair upazila, Manikganj district, outperformed the experimental field at Sher-e-Bangla Agricultural University, Dhaka. The final experiment conducted in the fourth year aimed to develop an integrated management approach against major capsicum pests using six packages. Package P 2 (black polythene + field sanitation + pheromone trap + Spinosad-45% SC @ 0.4 ml/L of water with a 7-day interval) demonstrated the best performance in terms of insect pest incidence, yield and yield-contributing factors. The untreated controlled plots (P 6 ) exhibited the lowest performance. Overall, the study concludes that package P 2 , comprising black polythene, field sanitation, pheromone trap, and Spinosad-45% SC @ 0.4 ml/L of water, presents an effective integrated management approach against major pests infesting capsicum. A dissertation Submitted to the faculty of Agriculture, Sher-e-Bangla Agricultural University, Dhaka In partial fulfilment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN ENTOMOLOGY 2021-01-01T00:00:00Z http://localhost:8080/handle/123456789/4780 HOST PLANTS, POPULATION DYNAMICS, SPECIES DIVERSITY, BIOLOGY AND MANAGEMENT OF VEGETABLE LEAF MINER DAS, KRISHNA RANI Five experiments were conducted in different locations such as in Entomology laboratory and central farm of Sher- e- Bangla Agricultural University along with nine agricultural regions of Bangladesh during May, 2019 to July, 2021 to study the host plants, population dynamics, species diversity, biology and management of vegetable leaf miner. Thirty three different crop plants, ornamental plants and weeds under families Fabaceae, Solanaceae, Cucurbitaceae, Brassicaceae, Amaranthaceae, Asteraceae, Boraginaceae and Convolvulaceae were recorded as host plants for Liriomyza spp. in nine agricultural regions of Bangladesh. The leaf infestation percent caused by leaf miner on various host plants in these regions showed a substantial variation ranging from 5.24±2.11 to 83.37±18.45 while the highest infestation was recorded on yard long bean and the lowest infestation on bon begun in Dhaka region. Considering population dynamics the lowest number was recorded in September (3) followed by August (6.5) while the highest number was observed in April (362) followed by March (191.25). Weather factors such as average temperature, rainfall, relative humidity and monthly rainy days influenced Liriomyza population. Both morphological characteristics and morphometric measurements revealed that both the species Liriomyza sativae and Liriomyza brassicae were present in the adult leaf miner samples having average head length 1.54 ± 0.05 mm, thorax length 0.53 ± 0.017 mm, abdomen length 0.62 ± 0.015 mm. The molecular analysis confirmed the presence of two species Liriomyza sativae and Liriomyza brassicae in study area. L. sativae reared from water melon plants only exhibited low genetic diversity and the obtained values were 3 (N), 2.0 (h), 1.0 (S), 0.66667 (Hd), 0.0030 (Pi) and 0.66667 (K). The development period from egg to adult was 19.56 ± 2.83 days where egg stage lasted for 2.12 ± 0.31 days, larval stage 4.57 ± 0.49 days and pupal stage 7.85 ± 0.67 days in laboratory condition. Irrespective of sex, the longevity of adult leaf miner was 1.5 ± 0.46 days without food source whereas 4.9 ± 2.20 days with supplementary food source. In case of tomato, Proclaim 5SG @ 1.0g L water, Tracer 45SC @ 0.4 ml L -1 water and Vertimec 018EC @ 1.2 ml L -1 water were most effective against Liriomyza leaf miner in both laboratory and field condition. Regarding yard long bean, Tracer 45SC @ 0.4 ml L -1 water and Ecomac 1.8EC @ 1.0 ml L -1 water were most effective against leaf miner among all tested biopesticides in both laboratory and field condition. These treatments attributed to higher yield and might be effective in controlling vegetable leaf miner. A Thesis Submitted to the Faculty of Agriculture Sher-e-Bangla Agricultural University, Dhaka, In partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY IN ENTOMOLOGY 2021-01-01T00:00:00Z http://localhost:8080/handle/123456789/3773 SURVEY AND MOLECULAR DETECTION OF FRUIT FLY SPECIES OF GUAVA IN BANGLADESH AND ITS INTEGRATED MANAGEMENT RAHMAN, MD. HABIBUR 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 4 which was statistically similar to Male Annihilation Technique (MAT). A DISSERTATION SUBMITTED TO Sher-E-Bangla Agricultural University, Dhaka in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY (Ph.D.) 2021-06-01T00:00:00Z