Entomocidal Efficacy of Different Botanical Extracts against Cotton Mealybug, Phenacoccus solenopsis Tinsley (Sternorrhyncha: Pseudococcidae)

Abstract

Use of botanicals is an age-old practice where people used to utilize the extracts from the plant parts to control the insects. In the present study entomocidal effect of different plant extracts was studied against cotton mealybug, Phenacoccus solenopsis (Tinsley), Hemiptera, Pseudococcidae. Two experiments were carried out in the laboratory of Entomology Department, Gomal University, Dera Ismail Khan, Pakistan. Five treatments, viz. Neem (Azadirachta indica), Ak (Calotropis procera), Bitter Cress (Cardamine hirsuta), Ajwain (Trachyspermum ammi), Hareer (Terminalia chebula) and Garlic (Allium sativum) were evaluated at three different concentrations of 1, 2 and 3% and replicated three times. The adults or 3rd instar nymphs of mealybugs were exposed to botanical extracts on Hibiscus rosasinensis leaves in glass petri dishes at constant conditions of 27±20C, 65± 5% R.H. In both experiments, A. indica extracts showed a higher mortality of both adult and 3rd instar of cotton mealybug at all the tested concentrations as compared to other treatments. The efficacy of the evaluated plant extracts increased by increasing the exposure period. From the overall mean results, A. indica (Neem) seed extract at 2% registered highest (51.37%) mortality of the adult cotton mealybug. Similarly, A. indica seed extract at 3% registered highest (45.00%) mortality of 3rd instar of cotton mealybug, whereas, lowest mortality was recorded in C. procera extracts at all the tested concentrations. The present results might help in getting better and safer control of cotton mealybug.