PRELIMINARY SURVEY OF MEALYBUG INCIDENCE AND INFESTATION ON PAWPAW (Carica papaya L.) IN A RAINFOREST ECOLOGY IN NIGERIA
Keywords:pawpaw, rainforest ecology, relative abundance, species richness, survey,
Field surveys were carried out at four selected locations within Obafemi Awolowo University Campus, Ile-Ife, Nigeria between August and December, 2017 to determine incidence, species richness and relative abundance of mealybugs on pawpaw (Carica papaya L.). Six species of mealybugs namely; Paracoccus marginatus (Williams and Granara de Willink), Ferrisia virgata (Cockerell), Planococcus citri (Risso), Maconellicoccus hirsutus (Green), Phenacoccus solenopsis (Tinsley), and Planococcus njalensis (Laing), were present on pawpaw in the selected locations. The results showed that P. marginatus had the highest mean abundance (160.2 30.36) and had highest relative abundance in the sampling period of August to December. The mean abundance of other mealybug species was P. citri (67.2 9.27), F. virgata (59.4 16.04) and M. hirsutus (52.4 7.16) with the lowest abundance recorded for P. solenopsis (16.2 4.07) and P. njalensis (7.6 1.33) across the locations and the sampling period. The abundance of P. marginatus and M. hirsutus increased progressively throughout the sampling period. In general, there was an increase in population density of the mealybugs from August to December. The significant higher population of P. marginatus and its predominance over other mealybug species suggest its tendency to cause potential damage and yield loss of pawpaw if necessary measures are not put in place to curtail the infestation of the insect.