Biological control of pepper pests in organic agriculture

During 2016-2017, experiments were performed at Vegetable Research and Development Station Bacau, Romania, in order to evaluate the biological control of major pests of organic peppers grown in tunnels. The main pests in pepper crops were onion thrips (Thrips tabaci Lind.), two-spotted spider mite (Tetranychus urticae Koch), corn earworm (Helicoverpa armigera Hbn.) and greenhouse whitefly (Trialeurodes vaporariorum Westw). Release of Amblyseius swirskii At.-H. at rates of 700,000-1,000,000 ex. ha^‑1 was effective against onion thrips in peppers during August-September. The predator, Phytoseiulus persimilis At.-H. has a very good efficiency in control of two-spotted spider mite in peppers at 50,000-100,000 ex. ha^‑1 release rate. In control of corn earworm, the best efficacy (95.8%) was achieved by treatment with Konflic at 0.3%, followed by Neem oil at 0.3% (efficacy 86.7%) and ProBalance at 0.3% (efficacy 45.2%), 3 days after treatment. In order to control greenhouse whitefly attack, the variants with Eretmocerus eremicus Rose and Zolnerowich had a parasite rate of 25.4% in the third decade of August, compared to 18.3% parasitism with Encarsia formosa Gahan at the same release rate (6 ex. m^‑2).