Fluctuation and temporal-spatial distribution of tuthillia cognata (hemiptera, psyllidae) and ocyptamus persimilis (diptera, syrphidae) on camu-camu myrciaria dubia (myrtaceae) in ucayali, Peru

Tuthillia cognata Hodkinson, Brown & Burckhardt, 1986 (Hemiptera, Psyllidae), is a main pest on camu-camu culture Myrciaria dubia H.B.K. Mc Vaugh (Myrtaceae) in the Peruvian Amazon. The aim of the current research was to evaluate the fluctuation and spatial and temporal distribution of T. cognata and biological control by Ocyptamus persimilis (Curran, 1930) (Diptera, Syrphidae), from January to November 2004 at San Juan and Padre Bernardo villages, Pucallpa, Ucayali, Peru. The number of nymphs and adults of T. cognata were found higher during the wet than in the dry season, but not the number of eggs neither of colonies. Eggs, nymphs and adults preferred the upper third of plant in comparison to the middle and lower third in both places. The exception was the presence of eggs at San Juan, without a distinct preference by any part. No differences were observed in the percentage of infestation by T. cognata between both places and between dry and wet seasons. For O. persimilis there were no differences in number of eggs, larvae and pupae between dry and wet seasons. Eggs, larvae and pupae preferred the upper third of the plants in comparison to the other parts in both places. Both species, T. cognata and O. persimilis, presented an aggregate dispersion model. A direct relation between number of colonies of T. cognata and O. persimilis was found. However no correlation was found between number of eggs, nymphs, and adults of T. cognata and number of eggs, larvae, and pupae of O. persimilis.