Managing Fusarium oxysporum f. sp. vasinfectum Race 4 with beneficial microorganisms including entomopathogenic fungi

Abstract

Fusarium spp. are dangerous pathogens of several commercially important crops around the world. Among non-chemical alternatives, beneficial microorganisms offer a potential control option for Fusarium and other soilborne pathogens. A greenhouse study was conducted using cotton as a model plant and F. oxysporum f. sp. vasinfectum Race 4 (FOV Race 4) as the pathogen to evaluate the efficacy of commercial formulations of microbial and botanical biopesticides. Streptomyces lydicus (Actinovate® AG), Bacillus amyloliquefaciens (Stargus®), giant knotweed extract (Regalia®), entomopathogenic fungi - Beauveria bassiana (BotaniGard® ES), Isaria fumosorosea (PFR-97™ 20% WDG), and Metarhizium brunneum (M. anisopliae; Met52® EC) were applied to FOV Race 4 infested soil in three treatment regimens, and the growth of susceptible Pima cotton seedling growth and health was monitored for 5 weeks. Treatments were generally effective against antagonizing FOV Race 4 especially when applied multiple times at a lower rate or once at a higher rate. Entomopathogenic fungi were as effective as other products that are exclusively used for disease management. Beauveria bassiana provided superior control for a long period compared to other treatments. This study reports the efficacy of non-chemical alternatives against FOV Race 4 and the potential of using entomopathogenic fungi for disease management in addition to their normal role of arthropod pest management.