Brevibacillus choshinensis restricts harmful Eurygaster integriceps in wheat-sown fields and enhances beneficial insect population

Abstract

This study was conducted to determine the effects of plant growth-promoting bacteria (Brevibacillus choshinensis) on Eurygaster integriceps Puton, 1881 (Hemiptera: Scutelleridae) and the predators Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) and Coccinella septempunctata L. (Coleoptera: Coccinellidae) during the 2022–2023 season. The study was laid out according to a completely randomized factorial design with five replications, including areas with and without B. choshinensis application. Sampling was carried out every 7 days until the harvest period. Predator insect species C. carnea, C. septempunctata and Sunn pest (E. integriceps) found in wheat plots were determined using the visual counting method. According to the results, B. choshinensis treatment boosted beneficial insect population and restriced E. integriceps over control plants. E. integriceps population reduced up to 75%, 100%, 66% and 92% compared to control at the 1st., 2nd., 3rd. and 4th. observation times, respectively. In addition, foliar B. choshinensis treatment reduced E. integriceps population by 6.3-fold (from 0.63 to 0.10) over control plots. Number of beneficial insects per plot were determined as 1.35 and 6.75 at control and PGPB treatmen, respectively, therby increasing by 5-fold over control. In conclusion, it is thought that B. choshinensis can be an alternative bio-insecticide that can be used to control the harmful insect population and to encourage the beneficial insect population. In addition, new researches are needed to understand the mechanisms by which B. choshinensis treatment suppresses E. integriceps populations while attracting beneficial insect communities.