Seasonal prevalence of giant mealy bug Drosicha mangiferae (Homoptera: Pseudococcidae) in the college of home economics, Dhaka, Bangladesh

Abstract

The seasonal prevalence of giant mango mealy bug, Drosicha mangiferae and their host preference was observed fortnightly at the College of Home Economics in Dhaka City from January 2015 to January 2016. Tree and bird species were also noted during the study period. 24 rows of 190 trees belonging to 23 species were identified and observed for counting mealybug population. Out of 18,312 recorded Mealy bugs, 73% were found on the host plants and the rest 27% were in the corridor site. Mealybugs were most abundant during January to March that gradually decreased during April to July. Among 23 species of plants, 11 species were susceptible to mealybug attack whereas the mealybugs have never been seen to attack or climb the rest 12 species of plants. No Mealy bug was found during August to December. Mealybugs were found at a temperature ranging 19 °C to 30 °C, rainfall 1 mm to 359mm, relative humidity 66-84% and average day length 651.5 minute to 813 minute. Mealybugs were negatively and weakly correlated with temperature (r = -0.446), rainfall (r = -0.454), relative humidity (r = -0.032) and day length (r= -0.379). A total of 23 bird species was recorded, belonging to 8 Orders and 16 Families where prevalence of insectivorous bird; which could play role in mealybug population control, is comparatively low. Establishing an ecological balance between mealybugs and its natural predators is recommended for preventing the outbreak of mealybug.