Natural enemies in alternative plants during the soybean and corn offseason in Cruz Alta, Rio Grande do Sul

ABSTRACT. Identifying the behavior of natural enemies during the crop offseason is a key tool for integrated pest management. The objective of this work was to evaluate the population density of natural enemies of the plants Chloris distichophylla, Andropogon bicornis, and Erianthus angustifolium and to analyze the influence of the structural complexity of these plants on the present population. During the offseasons of 2014, 2015, and 2016, 150 plants of each species were evaluated and subdivided into different clump diameters. The species Lycosa spp., Eriops connexa, Cicloneda sanguinea, Coleomegilla quadrifasciata, Lebia concinna, and Harmonia axyridis were identified. A. bicornis was the plant with the highest population density, followed by C. distichophylla and E. angustifolium. Plants with greater structural complexities sheltered a higher population density of natural enemies.