Population dynamics of Aceria guerreronis Keifer (Acari: Eriophyidae) and associated predators on coconut fruits in Northeastern Brazil

Abstract

Neotropical Entomology 37(4): 457-462 (2008) PALAVRAS-CHAVE: Ácaro do coqueiro, ácaro predador, controle biológico, PhytoseiidaeABSTRACT -Aceria guerreronis Keifer can cause severe damage to coconuts in several countries around the world. Rare studies have been conducted to determine the predatory mites associated with A. guerreronis in Brazil. The study evaluated the prevalence of A. guerreronis and associated predators on the bracts and on the surface of the fruits underneath the bracts, for 12 months, on coconut palms grown along the coast of the States of Alagoas, Paraíba and Pernambuco, Northeastern Brazil. Mites of 10 families were found, but by far the most abundant species was A. guerreronis, corresponding to 99.5% of the mites collected. The prevailing species amongst the predators were the Phytoseiidae mites Neoseiulus baraki (AthiasHenriot) and Neoseiulus paspalivorus (De Leon). These are fl at mites that have short limbs, characteristics that allow them to invade the main habitat occupied by A. guerreronis. Other predators were found, but in low numbers, due mainly to their diffi culty in reaching the fruit areas most inhabited by A. guerreronis. However, these mites could prey on that pest when it leaves its preferred habitat to disperse. No signifi cant correlations were observed between the levels of abiotic factors and the population levels of A. guerreronis or of the phytoseiids associated with it. This probably occurred due to the simultaneous and confl icting effects of those factors on the mites in the fi eld, or to signifi cant differences between the climatic factors measured in the environment and those prevailing in the habitat occupied by A. guerreronis.

Status of Aceria guerreronis Keifer (Acari: Eriophyidae) as a Pest of Coconut in the State of Sao Paulo, Southeastern Brazil

“…However, this was not the case. Although the predatory mites A. neochiapensis, E. citrifolius, Proprioseiopsis neotropicus (Ehara), and Proprioseiopsis ovatus (Garman) were found in this study, but not in studies conducted in northern and northeastern Brazil (Lawson-Balagbo et al 2008, Reis et al 2008, de Souza 2010, their densities were very low, corresponding to not more than three mites per 1,000 fruits. In addition, these mites were also infrequent, occurring in at most 3.3% of the analyzed plants, contrasting with the occurrence of the coconut mite on 35.3% of the plants.…”

“…Studies to evaluate the levels of occurrence of the coconut mite and its natural enemies in Brazil have been conducted almost exclusively in the north and northeast regions (Navia et al 2005, Reis et al 2008, de Souza 2010. Unpublished observations in São Paulo suggest its incidence to be low; growers from this state do not consider it as major problem on coconut.…”

Morphological variation and reproductive incompatibility of three coconut-mite-associated populations of predatory mites identified as Neoseiulus paspalivorus (Acari: Phytoseiidae)

“…It causes severe damage to the crop by attacking the meristematic tissues underneath the bracts. According to recent assessments the abundance of the coconut mite and its damage to the crop may be lower, and the predator fauna associated with coconut mite may be richer in certain areas of Brazil than in Africa (Benin, Ghana and Tanzania) and Sri Lanka (Fernando et al 2003;Lawson-Balagbo et al 2008;Reis et al 2008;Negloh et al 2010;Fernando et al, unpublished). Over the past two decades, attempts were made to control the pest through the use of chemicals and biopesticides.…”

“…The predatory mite Neoseiulus paspalivorus (DeLeon) (Acari: Phytoseiidae) is the most common natural enemy associated with the coconut mite in Brazil (Lawson-Balagbo et al 2008;Reis et al 2008). In Benin and Ghana, West Africa, N. paspalivorus was also frequently reported on infested coconuts (Negloh et al 2010).…”

Pode Euseius alatus DeLeon (Acari: Phytoseiidae) predar Aceria guerreronis Keifer (Acari: Eriophyidae) em coqueiro?

“…A espécie é encontrada predominantemente em folhas (Gondim Jr & Moraes 2001), mas ocasionalmente também é coletado em frutos infestados por Aceria guerreronis Keifer (Reis et al 2008). As dimensões relativamente grandes do predador difi cultam sua penetração abaixo das brácteas dos frutos, onde se encontra A. guerreronis; a distância entre a superfície do fruto e a superfície ventral das brácteas pode variar de 75 μm a 99 μm, dependendo da variedade (Aratchige 2007).…”