Injury and damage dynamics of Diceraeus melacanthus Dallas, 1851 (Hemiptera: Pentatomidae) in corn subjected to early defoliation

ABSTRACT The green-belly stink bug is an early pest in the second crop of corn, following soybean. The dynamics of infestations by this pest in systems where corn is defoliated in the early stages is still unknown. Therefore, the objective was to evaluate the feeding of the stink bug on corn subjected to early defoliation. In a greenhouse, used a 2 x 4 factorial design, with two cultivars: BRS3042 VTPRO2 and 1F640PRO2, and four treatments: Without stink bug and with plant cutting (WSB-C); With stink bug before cutting (SB-BC); With stink bug after cutting (SB-AC); With stink bug and without cutting (SB-WC), with ten repetitions. Cutting of the plants was performed at the V3 stage, at a height of five centimeters above the soil. Infestation with stink bugs was carried out five days after emergence and/or after cutting, with two stink bugs per pot. The following were evaluated: injury score, height, stem diameter, fresh and dry plant weight. The plants that were not cut (SB-WC) presented the highest values in height and diameter, resulting in injury scores around 1 compared to those that were infested after the cut (SB-AC), which had scores varying between 3 and 4 and had smaller height and diameter. It was concluded that removing the leaf surface impairs the establishment of the corn plant, and with the infestation of the green-belly stink bug, the severity of the damage increases.