Biocontrol evaluation of Beauveria bassiana BVECA48 strain against Macrostylus nebulosus weevil in coffee plantations

Overview

This research project focuses on evaluating the entomopathogenic fungus Beauveria bassiana strain BVECA48 as a biological control agent against the Macrostylus nebulosus weevil, a pest that has been causing foliar damage in coffee seedlings and regrowths in plantations in Grecia, Costa Rica since 2019. The study aims to reduce reliance on chemical pesticides by leveraging a naturally occurring fungal strain isolated from mummified insects. Beyond pest control, the project explores the endophytic capacity of the fungus to promote plant growth, offering dual benefits for coffee production systems.

Technical specifications

Key research components:

• Morphological identification and purification of the BVECA48 strain, stored in PDA medium and oil at the Biological Control Laboratory of the National University of Costa Rica
• Laboratory assays evaluating mycelial growth, degree of sporulation, and radial growth on PDA medium
• UV light resistance testing to assess field viability under tropical conditions
• Aggressiveness bioassays targeting the Macrostylus nebulosus weevil under controlled conditions
• Field-level evaluations in natural coffee plantation environments to assess real-world effectiveness in the insect-host relationship
• Planned molecular identification of the fungal strain to confirm genetic characterization

Potential applications:

• Biological pest management in coffee cultivation systems
• Reduction of chemical pesticide use in tropical agricultural settings
• Potential integration with other crops affected by curculionid pests

Technology readiness level

The research is at an early stage. The fungal strain has been isolated, morphologically identified, and purified. Initial laboratory characterization tests (sporulation, radial growth, UV resistance, and aggressiveness bioassays) are planned or underway. Molecular identification of the strain is pending due to budget constraints. Field evaluations in natural coffee plantation conditions have not yet been initiated. The project requires additional funding to complete molecular analysis and proceed to comprehensive field validation before the strain can be recommended as a viable biocontrol option for commercial deployment.