Compatibility Of Beauveria Bassiana With Amblyseius Barkeri To Control Frankliniella Occidentalis And Application Of An Efficient Attractive Card

This research focused on Beauveria bassiana, Frankliniella occidentalis and Amblyseius barkeri. The virulence of eight B. bassiana isolates against first instar nymph of F. occidentalis was evaluated in a laboratory-controlled environment, and its compatibility with the predatory mite A. barkeri were tested in greenhouse. In addition, an efficient attractive card to F. occidentalis was examined in greenhouse.The major results are listed as follows:The virulence of eight B. bassiana isolates against first instar nymph of F. occidentalis was evaluated in a laboratory-controlled environment. Four isolates NA-2, TL-7, SZ-15 and RSB had high virulence to the first instar nymph with 90.83%, 90.80%, 92.50% and 100.00% mortality at the dose of 108 conidia?mL-1, respectively. Among the four isolates, isolate RSB was the most virulent, with LT50 of 2.383d and LC50 of 1.53×103 conidia?mL-1.The non-target effects of RSB on A. barkeri, an important predator of F. occidentalis, were investigated.Results showed that RSB-treated A. barkeri could develop into adult stage. RSB did not significantly reduce the developmental duration, fecundity and longevity of A. barkeri compared with control, with the developmental duration of 5.9 d, fecundity of 33.850 d and longevity of 1.78 individual, indicating that the isolate RSB had no significant negative effects on the non-target predator A. barkeri.The effects of an emulsifiable conidial formulation of B.bassiana RSB and A. barkeri were tested for efficacy against F. occidentalis in hanging over. The number of F. occidentalis was lowest on the 9th day after application(1.17 individual per leaf), then slowly rised on the 11th day (3.17 individual per leaf). The results showed that combined applications of B.bassiana RSB and A. barkeri reduced populations of F. occidentalis.The effects of an emulsifiable conidial formulation of B.bassiana RSB and A. barkeri were also tested for efficacy against F. occidentalis in greenhouse. The results showed that the fungus significantly reduced both the adult and nymph populations of F. occidentalis. And combined applications of both natural enemies resulted in greater F. occidentalis reduction than applications of mites alone or control. The dropping rate of adult thrips was 62.88% on the3th day after application, and was highest on the 9th day (77.53%), then slowly declined; the dropping rate of nymph thrips was lower than the dropping rate of adult thrips. It reached 73.99% on the 3th day after spray, and then decreased to 59.63% on the 11th day.An efficient attractive card to F. occidentalis was also determined in greenhouses with different vegetables.The average numbers of F. occidentalis caught by the attractive cards was highest 5 times more than the common sticky cards after seven days. The attractive card, as a tool of monitoring and control, was convenient to use, efficient.