HOST PLANTS OF THE COTTON MEALYBUG, PHENACOCCUS SOLENOPSIS TINSLEY (HOMOPTERA: PSEUDOCOCCIDAE) IN THREE SELECTED TOWNS OF NIGERIA, AND ITS INFESTATION PATTERN

Abstract

Reconnaissance surveys were carried out for field infestation of Phenacoccus solenopsis Tinsley from 2006 to 2010 in seventy five (75) vegetable gardens located in three (3) towns– Ogbomoso, Abeokuta and Ibadan in Nigeria. No cotton mealybug infestation was observed in Abeokuta and Ibadan, but twenty four (24) plants in 16 different families were observed as its hosts in Ogbomoso area. Of the 24 species, weeds constituted 45.8%, vegetables 29.1%, herbs 12.5%, cereals 4.2%, fruit trees 4.2% and pulse 4.2% each. Infestations started on the abasial leaf surface and advanced to the mid-ribs, petiole, young and succulent stems and buds. Corchorus olitorius and Amaranthus hybridus were the most susceptible of the trialled plant species with heavy root infestation in addition to that of the leaf. On heavily infested plants, certain ants were found together with P. solenopsis; on cowpea however, Aphis craccivora and the ants formed a complex with the mealybug on the flower buds. Of the three towns surveyed, P. solenopsis could be said to be restricted to backyard gardens around Ogbomoso at the moment. However, a nation-wide survey is very necessary now to determine the current status of the mealybug in Nigeria.