Premium
Efficacy of Beauveria bassiana (Bals.) Vuill. against the spruce bark beetle, Ips typographus L., in the laboratory under various conditions
Author(s) -
Kreutz J.,
Vaupel O.,
Zimmermann G.
Publication year - 2004
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.1439-0418.2004.00813.x
Subject(s) - beauveria bassiana , biology , bark beetle , conidium , bassiana , bioassay , bark (sound) , horticulture , curculionidae , entomopathogenic fungus , botany , biological pest control , zoology , ecology
In laboratory bioassays, the efficacy of the entomopathogenic fungus Beauveria bassiana against the spruce bark beetle, Ips typographus , was tested under various conditions. Four of the tested isolates and the commercial product Boverol ® caused 99–100% mortality when tested at a concentration of 1.0 × 10 7 conidia/ml at 25°C. Using B. bassiana isolate 138 at a concentration of 1.0 × 10 6 , the median survival time (MST) was 6.1 d and significantly longer compared with the MST of 4.2 and 4.0 d at 1.0 × 10 7 and 1.0 × 10 8 conidia/ml, respectively. In the next experiment, the beetles were maintained on spruce bark, filter paper or artificial diet during the bioassay with Boverol ® , and significant differences in the MST of 3.6, 2.5 and 5.3 d, respectively, were noticed. The experiment with Boverol ® at different temperatures showed that the beetles lived significantly longer at 15°C (MST 8.7 d) than at 20, 25, 30 and 35°C. At 25°C, the beetles died most rapidly (MST 3.5 d). At different relative humidities (RH) of 40, 70 and 100%, nearly all beetles were dead after treatment with a suspension of Boverol ® at 1.0 × 10 7 conidia/ml. At 40% RH, 49% of the untreated beetles died after 7 d. The best effects were achieved with the following bioassay: beetles were fed for three days on artificial diet, then dipped into a solution of 1.0 × 10 7 conidia/ml and transferred on a piece of spruce bark in Petri dishes at 25°C and 70% RH.