EVALUATUON OF PLANT EXTRACT AND MECHANICAL BAND AGAINST MANGO MEALYBUG (DROSICHA MANGIFERAE)

Abstract

The experiment was conducted at the Entomology laboratory and mango orchard at Sher-e-Bangla Agricultural University campus, Dhaka during the period from November, 2013 to May, 2014 to study the effect of some plant extracts and mechanical bands against mango mealybug. In laboratory seven plant extractsleaf of (neem, korobi, marigold, nishinda,tobacco,tomatoand neem seed kernel)were used to evaluate against 1st,2nd, 3rd instar nymph and adult female of mango mealybug. In field different mechanical bands(cotton, white plastic sheet, black plastic sheet, only grease, red cloth, black cloth, white cloth, cotton with insecticide, white plastic sheet with grease, black plastic sheet with grease) were used.In case of 1st instar mango mealybug at dipping and spraying neem seed kernel extract gave the highest mortality at 24 h, 48 h, 72 h, 96 h and 120 h resulted 5%, 10%, 15%, 13.3% and 5%, 11.67%, 13.33%, 16.67% and 8.33% respectively. Similar trend was found at 2nd and 3rd instar mango mealybug nymph in both dipping and spraying method. Neem seed kernel gave the highest mortality from 24 h to 120 h of post treatment. Treatment with all plant extracts following both spraying and dipping methods did not show any effect on the mortality of adult female of mango mealybug.Regarding the mechanical bands in field, black plastic sheet with grease gave the maximum reduction resulted 71.33%, 83.00%,and 84.70% in inflorescence, stem and leaf respectively at the 1stinstar nymph.At 2nd instar 79.25%, 71.33% and 86.33% reduction was found in inflorescence, stem and leaf respectively. At 3rd instar 87.33%, 86.67% and 94.33% reductionwas found in inflorescence, stem and leaf, respectively.