Host Range of the Newly Invasive Mealybug Species Paracocccus Marginatus Williams and Granara De Willink (Hemiptera: Pseudococcidae) in Two Ecological Zones of Ghana

The papaya mealybug Paracoccus marginatus Williams and Granara De Willink (Hemiptera: Pseudococcidae) has a wide host range and great potential to cause damage to economically important fruits, vegetables, and ornamental plants. It has already caused serious damage to the papaya industry since it invaded Ghana lately in 2009. To determine the host range of this mealybug species, host plants were sampled in 3 districts in the Eastern region and Legon in the Greater Accra region of Ghana. A total of 50 plant species in 20 families were identified as host of P. marginatus, including economically important hosts such as Carica papaya, Manihot esculenta, Mangifera indica, Solanum melongena Citrus sp and Theobroma cacao. Favourite hosts included Carica papaya, Manihot esculenta, Solanum melongena, hibiscus sp, Jathropha sp, Plumeria sp, Abutilon indicum and Adansonia digitata. Three new families, Plumbaginaceae, Bombaceae, and Lythraceae and eight new plant species; Launaea taraxacifolia, Euphorbia heterophylla, Codiacum variegatum, Codiacum aucubaefolium, Securinega virosa, Adansonia digitata, Lagerstroemia indica, and Plumbago auriculata were identified as hosts of P. marginatus. Paracoccus marginatus was also found to co-exist with other mealybug species in some economically important host plants. The wide host range of P. marginatus calls for quick action to be taken in other to reduce its devastating impact on economically important food crops, fruits, and vegetables in Ghana and to prevent its spread to other African countries.