Effect of green-belly stink bug, Dichelops furcatus (F.) on wheat yield and development

• Dichelops furcatus (F.) is a pest of corn and soybean in southern Brazil.
• Knowledge about its damage to the wheat crop is limited.
• During vegetative period 1 bug per plant reduces plant height, but not grain yield.
• During booting 2 bugs per plant reduces grain yield, but not at milky grain stage.
• At milky grain 8 bugs per m2 reduced proportion of normally developing seedlings.

The green belly stink bug, Dichelops furcatus (F.) (Hemiptera: Heteroptera: Pentatomidae) is a pest of corn and soybean in southern Brazil. It also occurs on wheat, but information on its damage to this crop is limited. To determine the need for sustainable IPM programs, the impact of this bug on wheat production should be determined. Studies were conducted in the screenhouse with 1, 2 and 4 bugs caged for 16 days on single plants, cv. ‘BRS Parrudo’. During the vegetative period (plants ca. 25 cm tall), all infestation levels significantly reduced plant height and ear head length, but did not reduce grain yield. Feeding damage caused tissue necrosis on leaves. During the booting stage, grain yield was significantly reduced with 2 and 4 bugs per plant; ear heads were small, discolored and abnormally developed. In 2013 and 2014 field trials, plants were infested for 18 days with 2, 4 and 8 bugs per m2 at vegetative, booting, and milky grain stage. At these infestation levels, there was no significant reduction in grain yield. There was a significant decrease in the number of normal seedlings resulting from seeds exposed to 8 bugs per m2 at the milky grain stage. Results suggest that, in general, there is no need to control D. furcatus on wheat, unless numbers are ≥8 bugs per m2 during reproductive period.