Effect of biological control agents in the management of powdery mildew disease of cucumber under field conditions

Abstract

The seed or root treatment with biocontrol agents or useful microorganisms may improve plant growth as well as provide protection against pathogens through a variety of mechanisms like induced systemic resistance, production of antibiotics or enzymes, production of plant hormones, competition with pathogens for space or nutrients, and direct parasitism on plant pathogens. In this study, Bacillus pumilus strain MK5 and Trichoderma atroviride ta001 were evaluated separately as well as in combination to control the powdery mildew disease of cucumber caused by fungi (Podosphaera xanthii or Erysiphe cichoracearum) for different two crop seasons (2021 and 2022). The minimum severity of powdery mildew (1.62%) was recorded under combined treatment of Trichoderma atroviride ta001 seed priming plus soil application with Bacillus pumilus strain MK5 as well as foliar sprays of T. atroviride ta001+ B. pumilus strain MK5 and provided 86.79% disease control over untreated plots. Maximum disease severity (12.27%) was observed under untreated control as compared to other treatments.