Premium
Insecticidal activity influence of destruxins on the pathogenicity of Paecilomyces javanicus against Spodoptera litura
Author(s) -
Hu Q.B.,
Ren S.X.,
An X.C.,
Qian M.H.
Publication year - 2007
Publication title -
journal of applied entomology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.795
H-Index - 60
eISSN - 1439-0418
pISSN - 0931-2048
DOI - 10.1111/j.1439-0418.2007.01159.x
Subject(s) - spodoptera litura , metarhizium anisopliae , paecilomyces , biology , spore , toxin , depsipeptide , pathogenicity , food science , botany , microbiology and biotechnology , biological pest control , lepidoptera genitalia , biochemistry
The bioactivities of destruxins (dtx), depsipeptides isolated from Metarhizium anisopliae , against Spodoptera litura were tested in laboratory. For contacting toxicities, dtx‐E was more effective than dtx‐A and dtx‐B. The LC 50 s values of dtx‐A, B and E were 197.98, 292.00 and 113.99 mg/l at 48 h after treatment, while the LT 50 s were 42.65, 59.45 and 23.68 h at 300 mg/l. In the experiment of antifeedant activity, dtx‐A, dtx‐B and dtx‐E at five concentrations (200, 100, 50, 25 and 12.5 mg/l) were bioassayed. Destruxins in a dose‐dependent manner gave an apparent antifeedant activity. Generally, dtx‐A, over dtx‐B and dtx‐E had the significant (P < 0.05) larger choice and no‐choice antifeedant indexes (CAIs and NCAIs). At the concentration of 200 mg/l, the CAIs or NCAIs of dtx‐A, dtx‐B and dtx‐E were 96.78, 84.93 and 85.90 or 89.75, 62.42 and 72.28 respectively. Furthermore, the synergistic activity of crude destruxin (CD) for pathogenicity of Paecilomyces javanicus strain Pj01 was detected. The LC 50 s values of single Pj01 and the mixtures of Pj01 plus CD at 100 or 200 mg/l (Pj01‐CD100 or Pj01‐CD200) were respectively 474.63 × 10 5 , and 197.45 × 10 5 or 113.11 × 10 5 spores/ml at the fifth day after treated. Meanwhile, Pj01, Pj01‐CD100 and Pj01‐CD200 gave the LT 50 s values of 6.99 day, 5.49 day and 4.21 day at 100 × 10 5 spores/ml. Clearly, dtx decreased the values of LC 50 and LT 50 of the strain Pj01.