The papaya mealybug Paracoccus marginatus Williams and Granara De Willink (Hemiptera: Pseudococcidae) has caused serious damage to papaya production since it invaded Ghana lately in 2009. To ease forecasting and develop a sampling technique to ensure effective monitoring and control of this mealybug species, studies on the population dynamics and distribution were undertaken in the Suhum-Kraboa-Coaltar and Akwapim South districts in the Eastern region of Ghana from July 2010 to May 2011. Multiple correlation studies were carried out between weather parameters and the different stages of P. marginatus on both leaf and fruit populations. Population trends revealed two similar peaks between August and September, and between January and March for the two districts, and an additional peak between April and May for the Akwapim South district. There was synchrony in the fluctuation patterns for crawlers, adults and egg sacs. Results on seasonal abundance revealed significantly (P < 0.05) higher densities of P. marginatus in the dry season than in the wet season on both fruits and leaf populations. Distribution patterns on fruit canopies reversed with change in season, while that on leaf canopies remained constant irrespective of seasons. Abiotic factors such as rainfall, temperature and relative humidity, as well as habitat type were found to have an influence on the dynamics and distribution of P. marginatus with more effects on crawlers and adults than on egg sacs and on fruits than leaf populations.
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