Habitat complexity and mite population on Caryocar brasiliense trees

Abstract

. The objective was to study the habitat complexity of mite populations on Caryocar brasiliense trees under natural and cultivated field conditions. The study was performed in the municipality of Montes Claros, in the state of Minas Gerais, Brazil, over 3 years. Three types of areas were studied: 1) Cerrado, 2) pasture, and 3) a university Campus. Several chlorotic spots were detected on leaves with larger populations of Tetranychus sp. and Eutetranychus sp. (Tetranychidae). The greatest numbers of Agistemus sp. (Stigmaeidae) on leaves and Histiostoma sp. (Histiostomidae) and Proctolaelaps sp. (Ascidae) on fruits were observed in the pasture, and that of Histiostoma sp. on leaves in the pasture and on the university Campus. In general, the herbivorous mites (e.g., Tetranychus sp.) found on C. brasiliense plants were correlated with more clayey soils with a higher cationic exchange capacity; larger populations of mites (e.g., Agistemus sp. and Histiostoma sp.) were found on the C. brasiliense trees with the largest crown sizes; and associations between predator mites (e.g., Agistemus sp.) and phytophagous mites (e.g., Tetranychus sp.1) were observed. Greater habitat diversity and more complex plant architectures favored the mite populations. The positive effect of loamier soil on herbivorous mites indicates that these species are adapted to Cerrado conditions. Some recorded species of herbivorous mites can be pests in commercial plantations of C. brasiliense.

Free-feeding organisms and galling insects (Hymenoptera) interactions on Caryocar brasiliense (Malpighiales: Caryocaraceae) trees, a savanna plant from Brazil

“…Lady beetles feed on sternorrhynchan hemipteran (e.g., aphids) and phytophagous mites, when these predators are very small (non-case of N. fulgurata) (Wäckers et al, 2017;Kaneko, 2018), and, consequently, favoring the phytophagous mite population, maybe, due to less competition with sucking insects. Another possibility is this lady beetle feeding also on Agistemus sp., bigger than species of the Tetranychidae genus, increasing phytophagous mites and reducing this important mite predator (Leite et al, 2020b). Sycophila sp.…”