Interference of Volunteer Corn from Different Origins and Emergence Time on Soybean Yield and Stress Metabolism

Abstract

Volunteer corn occurrence with soybean is favored by the glyphosate-resistant (GR) corn cultivation preceding soybean and no-tillage systems. Volunteer corn interference causes significant losses in soybean grain yield. The levels of crop losses change with the corn density, origin, and time of emergence. High levels of weed interference in crops can result in the production of reactive oxygen species and lead to the occurrence of oxidative stress. The objectives of this study were to evaluate the effects of interference of (1) different origins (individual plants and clumps) and times of emergence of volunteer corn on soybean growth, yield components, and grain yield loss; and (2) if the volunteer corn interference causes oxidative stress in soybean. Field experiment and laboratory analyses were performed. The evaluated variables were soybean yield components, grain yield, hydrogen peroxide - H2O2 content, and antioxidant enzyme superoxide dismutase - SOD, catalase - CAT, and ascorbate peroxidase - APX activities. Volunteer corn interference reduced the yield components and soybean yield. The highest yield losses were observed with volunteer corn clumps regarding individual plants. The interference of volunteer corn emerged 10 days before or on the same day as soybean caused the greater yield losses than those emerged 10 days after, independently of its origin. The content of H2O2 and enzyme SOD, CAT and APX activities changed in soybean leaves in response to the interference of volunteer corn plants and clumps. However, the results indicate that the volunteer corn interferences does not cause oxidative stress in soybean.

Pre-emergence control and interference of voluntary maize plants on a soybean crop in Brazilian Cerrado

“…The results of the highly competitive potential of voluntary maize plants interspersed with soybean were similar to those obtained by Rizzardi, Piasecki, Schons, Caverzan, and Langaro (2019), where competition from nine voluntary maize plants per m 2 reduced soybean yields by 75.9%. Alms et al (2016) observed a 71% reduction in soybean yield due to the presence of six maize plants per m 2 in repeated experiments with two different crops.…”

Interference and Economic Threshold Level of Transgenic Volunteer Soybean Plants in Maize Crop

“…The grain losses at harvest of these crops have caused an expansion in the incidence of volunteer plants in the succession crop. They can compete for space, water, nutrients, light, and host pests and diseases (Alms et al, 2016;Petter et al, 2016;Piasecki & Rizzardi, 2018;Rizzardi et al, 2019).…”