Evaluation of Biological Control Agents (Beauveria bassiana and Metarhizium anisopliae) Compared with the Chemical Insecticide Oxamyl for Management of the Fig Wax Scale Insect (Ceroplastes rusci) and Its Impact on Final Fruit Quality

This laboratory study was conducted to evaluate the insecticidal efficacy of two entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae, in comparison with the chemical insecticide Oxamyl ۲۴% SL, against different nymphal instars and adult stages of C. rusci. The goal was to identify effective management strategies that minimize chemical residues and enhance the quality of the final fruit product. The results demonstrated that Oxamyl ۲۴% SL was the most potent treatment, achieving the highest overall mean mortality rates across all stages, with peak efficacy observed against the second nymphal instar (۵۷.۵۸%) and the pre-oviposition adult stage (۴۹.۸۲%). Among the biological agents, B. bassiana exhibited significantly superior pathogenicity compared to M. anisopliae against all tested stages, with overall mean mortality rates ranging from ۳۲.۳۴% to ۴۴.۵۹%. The maximum efficacy of B. bassiana (۷۴.۱۲% mortality) was recorded against the first nymphal instar at ۳۰ days post-exposure, highlighting its cumulative effect. Notably, nymphal stages were consistently more susceptible to all treatments than adult stages. The study concludes that B. bassiana represents a highly promising biological alternative for integration into Integrated Pest Management (IPM) programs. Its high cumulative mortality and ability to penetrate the insect's protective wax coating offer a sustainable strategy for suppressing C. rusci populations. Adopting such a biological control agent could significantly reduce reliance on chemical insecticides like Oxamyl, thereby lowering pesticide residues in harvested figs and contributing to the production of safer, higher-quality fruit for the fresh market and food processing industries.

کلیدواژه ها:

Biological control ، Ceroplastes rusci ، Fig quality ، Food safety ، Entomopathogenic fungi ، Oxamyl ، pesticide residue