Populations of phytophagous bugs influenced by crop background and wild plants

Abstract

Plant-insect interaction governs the dynamics of insect populations with respect to their interrelation with the environment. The objective of the present study was to identify the influence of antecedent crops, species and diameters of wild plants on the quiescent population of phytophagous stink bugs. The experiment was conducted in the months of June and July in Parada Link, municipality of Santa Maria, Rio Grande do Sul state, Brazil in two fields under crops of rice and soybean. In the off season, alternative host wild plants such as Andropogon bicornis , Andropogon lateralis , and Erianthus angustifolius with 10, 20, 30 and 40 cm in diameter were selected. Six wild plants were sampled for each crop, species, and diameter, totaling 144 experimental units. The stink bug species were identified and quantified. Soybean and rice previous cultivation, as well as the species and diameter of the wild plant, influence the quiescent population of Dichelops furcatus , Edessa meditabunda , E. rufomarginata , Euchistus heros , Piezodorus guildinii , and Tibraca limbativentris phytophagous stink bugs. The host plants A. bicornis , A. lateralis , and E. angustifolius were utilized for the maintenance of the populations of phytophagous stink bugs in the off-season periods. Soybean cultivation in floodplain areas has a negative impact on the quiescent population of T. limbativentris .