Flutuação populacional da mosca-negra-dos-citros, Aleurocanthus woglumi (Hemiptera: aleyrodidae) e de seus inimigos naturais em um plantio de citros, Manaus, Amazonas, Brasil

Abstract

The citrus blackfly, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) is an important Asiatic pest which has been damaging the brazilian citriculture since it was introduced in the country, in 2001. This study had the aim to verify the populational fluctuation of citrus blackfly, A. woglumi, and of its possible natural enemies and the influence of biotic and abiotic factors on the fluctuation in Manaus/AM. The evaluations occurred fortnightly in a Sweet Orange (Citrus sinensis L.) crop, at Sítio Brejo do Matão (0251‟12.6‟‟ S; 06002‟40.6‟‟ O), during the period of December 2011 to November 2012. For the population fluctuation study of citrus blackfly and its associated and efective natural enemies, ten plants from the crop were selected at random. In each plant was placed a yellow sticky trap. On these same plants was conducted the population fluctuation study of citrus blackfly immatures (eggs and nymphs) and their distribution per quadrants (north, south, east and west). It was chosen at random a branch per quadrant in each tree, and from each branch were removed six leaves from the base, middle and apex of the branch totalizing 24 leaves per tree. The highest citrus blackfly peak occurred during the period of higher rainfall. There were no difference on the quantity of adults, eggs and nymphs of A. woglumi during rainy and dry period. There were no difference on the quantity of eggs and nymphs of A. woglumi among the quadrants. There were collected the natural enemies of A. woglumi from Neuroptera order, Chrysopidae family and Coleoptera: Coccinelidae. These preying on blackfly nymphs. The parasitic action of insects from Hymenoptera order belonging to Aphelinidae and Encyrtidae families was verified. Among the populations of parasitoids found, the genus Cales sp. and Arrenophagus sp. were the most correlated to the population fluctuation of citrus blackfly. The results of this work reflect the viability of establishing an integrated managing program of A. woglumi, being necessary complementary studies about the population fluctuation of A. woglumi and the biology of its natural enemies in a way the MIP program can be done effectively.