Influence of Certain Streptomyces Isolates on the Management of Gray Mold in Strawberries

Youness, Hamam E. H.; Amin, Mohsen Mohamady; El-deeb, Abdullah B. A.

doi:10.21608/ejp.2025.403757.1149

Influence of Certain Streptomyces Isolates on the Management of Gray Mold in Strawberries

Document Type : Original Article

Authors

¹ Plant Pathology Research Institute, Agricultural Research Center (ARC), Giza, Egypt.

² Department of Agriculture Botany- Microbiology, Faculty of Agriculture, Al-Azhar University, Cairo, Egypt.

10.21608/ejp.2025.403757.1149

Abstract

Strawberry is a very important crop in Egypt for local consumption and export. Gray mold, caused by Botrytis cinerea, represents one of the most severe diseases in pre- and post-harvest stages. In this study, twelve isolates of Streptomyces were obtained from healthy-looking strawberries collected from local markets. All isolates inhibited the linear growth of the pathogen on medium in vitro, and the most promising isolates identified based on their morphological and biochemical characteristics were Streptomyces lavendulae, S. glaucescens, S. albus, S. violaceoruber, and S. flavotricini. All five isolates effectively protected strawberry fruits from gray mold when applied as foliar treatments on Festival and Fortuna strawberry varieties. S. glaucescens provided 96.3 and 87.3% protection compared to 0.0% in the control, and reducing the infected area in infected fruits to 32.5 and 49.8% compared to 83.9 and 81.2% in the control for Festival and Fortuna, respectively. Soluble solids content, vitamin C, and color density showed no significant differences among treated strawberries with such Strptomyces isolates, or they decreased. However, the levels of firmness and titratable acidity varied depending on the varieties.

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