ABSTRACT The objective of this study was to determine the effects of temperature, rainfall, plant age, leaf organic compounds, leaf nitrogen (N) and potassium (K) levels, leaf trichomes, predators, and parasitoids on intensity of pest attack on Phaseolus vulgaris. Higher densities of Bemisia tabaci and Caliothrips brasiliensis were observed in periods of higher temperature, with the opposite being observed for Aphis cracivora. Higher attacks of Empoasca kraemeri and A. cracivora in older plants and B. tabaci in younger plants were observed. On the other hand, higher numbers of the parasitoid Adialytus spp. and predator Cycloneda sanguinea were observed in older plants. Older plants possessed leaf nonacosane concentrations and these compounds correlated positively with A. cracivora. Higher attack of A. cracivora in plants with higher N leaf concentration and decreased attack of E. kraemeri with plants with higher K leaf concentrations were observed. Glandular trichomes correlated negatively with B. tabaci and Adialytus spp. and positively with E. kraemeri and A. cracivora. The natural enemies Encarsia formosa, which are important, of the parasitoid of B. tabaci; Adialytus spp., Orius spp., spiders and C. sanguinea correlated with A. cracivora; and Orius spp., which in turn correlated with E. kraemeri.
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