Dual Action of (Hypocreales; Cordycipitaceae) Endophytic Stains as Biocontrol Agents against Sucking Pests and Plant Growth Biostimulants on Melon and Strawberry Field Plants.

Entomopathogenic fungi (EPF) can colonize plant tissues and serve crops not only as biopesticides but also as biostimulants that promote plant growth and trigger defense mechanisms. In this context, field trials were conducted evaluating two commercial strains of the entomopathogen (Hypocreales: Cordycipitaceae), GHA (Botanigard) and PPRI 5339 (Velifer ES) and a wild strain (AP0101) isolated from Achaia, Greece. The three strains were investigated in the field for their endophytic effects on melon (Cucurbitales: Cucurbitaceae) and strawberry sp. (Rosales: Rosaceae) plants and in particular for their ability to colonize plant tissues, control infestations of sucking insects (Hemiptera: Aphididae), (Hemiptera: Aphididae) and (Thysanoptera: Thripidae), and improve plant growth parameters (plant height, number of flowers and fruits). All experimental fungal strains successfully colonized both plants. A significant decrease in the aphid and thrip populations was observed in the treated plants compared to the untreated control. As for plant growth, the number of flowers and fruits was significantly increased in plants treated with strains AP0101 and PPRI 5339. Our results clearly indicate that fungal endophytes can efficiently act as dual action agents demonstrating both insecticidal and growth-promoting effects.