Seasonal incidence of papaya mealybug, Paracoccus marginatus Williams and Granara de Willink and its natural enemies with weather parameters

Abstract

Seasonal incidence of papaya mealybug, Paracoccus marginatus Williams and Granara de Willink was studied during 2013-2014 in relation to weather parameters. It was observed that the insect was prevalent throughout the year. The peak activity of papaya mealybug was observed from 13th to 18th meteorological week. The maximum population was recorded (105.8 mealybugs/5 cm2/leaf/plant) in the 18th meteorological week. The mealybug incidence was positively correlated with maximum temperature and sunshine hours. Whereas, it was negatively correlated with minimum temperature, rainfall and relative humidity. In case of natural enemies of papaya mealybug it was observed that the highest population of Acerophagus papayae, Pseudleptomastix maxicana, Aprostocetus nr. purpureus and coccinellids were recorded (12.2, 7.4, 6.2 and 6.4 adults/leaf/ plant) in the 18th, 15th, 9th and 11th meteorological week, respectively. Further it was also noticed that natural enemies population was density dependent and positively correlated with maximum temperature and sunshine hours. Whereas, it was negatively correlated with minimum temperature, rainfall, morning and afternoon relative humidity.