Bark beetles in a mixed plantation of Bertholletia excelsa and Hevea brasiliensis in the southern amazon

Abstract

Bark beetles (Curculionidae: Scolytinae) are wood borers with the potential to cause significant damage in forest plantations. Studies of this group are more common in plantations of Eucalyptus, and Pinus, but the increase of planting with other forest species, such as Brazil nut and rubber trees, indicates the need for monitoring of Scolytinae in these additional forest areas. Thus, the objective of this work was to evaluate an assemblage and the main species of bark beetles in a mixed plantation of Brazil nut trees (Bertholletia excelsa Bonpl.) and rubber trees (Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg.) in Southern Amazonia. Twelve ethanol traps were used and collections were carried out biweekly for one year. The collections were evaluated descriptively way with entomofaunistic analysis, and population fluctuation and its dispersion were determined. A total of 2,738 individuals were collected, with a total of 17 species distributed in nine genera, of which Cryptocarenus Eggers 1937 and Xyleborus Eichoff 1864 showed the greatest representation. Cryptocarenus diadematus Eggers, Cryptocarenus heveae (Hagedorni), Cryptocarenus seriatus Eggers, Xyleborus affinis Eichhoff, and Xyleborus spinulosus Blandford were categorized as dominant, very abundant, very frequent, and constant. The assemblage of Scolytinae in the Brazil nut tree and rubber tree mixed plantation had a greater abundance in the rainy season, with the highest averages and population peaks. The species with the greatest representation also presented a greater number of individuals in the rainy season with aggregate dispersion.

Coleoborers (Curculionidae: Scolytinae) in native and homogeneous systems of Brazil nut (Bertholletia excelsa bonpl.) in the Southern Amazon, Brazil

“…The species Cryptocarenus seriatus showed a positive correlation with the maximum temperature and Cryptocarenus hevea with precipitation. Monteiro, Garlet and Carvalho [ 41 ] studied the occurrence of Scolytinae in a consortium of Brazil nut and rubber tree, also in the Southern Amazon, and found that the species Cryptocarenus diadematus was negatively correlated with the average and maximum temperatures and positively with the minimum temperature, maximum humidity, minimum humidity and precipitation. In the same study, these authors found a positive correlation between precipitation and abundance of Cryptocarenus seriatus .…”