HOST PLANTS, POPULATION DYNAMICS, SPECIES DIVERSITY, BIOLOGY AND MANAGEMENT OF VEGETABLE LEAF MINER

Abstract

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.