Variation in composition of cacao floral visitors (Theobroma cacao) among five production systems in Sara Ana, Alto Beni, Bolivia

Summary

The Cocoa (Theobroma cacao) production systems vary from monocultures to complex agroforestry according to their structure and the diversity of accompanying trees. These variations create different environmental conditions, which can affect the entomofauna associated with these crops. In this study, we compared the composition of floral visitors among five production systems, considering environmental variables and the variety of cacao trees. Arthropods were captured directly on open flowers using tangle-traps. We applied a detrended correspondence analysis to characterize the composition of floral visitors and used the model selection approach to elucidate the effect of crop systems, tree characteristics, and environmental conditions on the composition of arthropods. We captured ten insect orders of which Hemiptera, Hymenoptera, Diptera, Coleoptera, and Thysanoptera were the most representative. We found variation in arthropod composition between the successional agroforestiy system and both types of monocultures (P < 0.05); however, there were no differences in order richness, heterogeneity, or abundance of floral visitors among cacao production systems (P> 0.40). The abundance of thrips, varied according to the number of open flowers and the production system (negative binomial distribution: X24 = 14.96, P < 0.001). Entomofauna studies in cocoa crops help to identify potential pollinators and understand their ecology; with this knowledge, pollination yields in these production systems can be improved.