Introduction of Beauveria bassiana as a biological control agent for Tribolium castaneum in Kerman province

Abstract

Barley, Hordeum vulgare, one of the important crops in the word, is used in malting, feed and food industries. The red flour beetle, Tribolium castaneum, was found wherever grains or other dried foods are stored. Disinfestations of barley using chemical methods to kill insects, in this research, for the first time we isolated the pathogenic KB512 of entomopathogenic fungi Beauveria bassiana from soil and insects, which produced aerial and submerged conidia and blastospores in laboratory conditions. We investigated the best conditions for the production and utilisation of spore suspension to spray the larvae of T. castaneum, which is one of the important pests in Kerman province (Iran). One hundred and eighty isolates that naturally infected by T. castaneum were reared during spring and summer seasons 2010–2011. The pathogenicity test was carried out with direct spray. To bioassay the isolates, three concentrations of the spore suspension were prepared as follows: 1 × 10⁶ and 1 × 10⁸ conidia/ml. The pests were sprayed by aerial conidial suspension, which was prepared by 0.01% Tween 80 in distilled water, and the controls were sprayed by 0.01% Tween 80 in distilled water. After spraying the pests, the plates were incubated at 25 ± 1 °C and 80% of relative humidity. Then, the treated pests were monitored every day for the fungal growth and mortality.

Keywords:

• Beauveria bassiana
• biological control
• entomopathogenic fungi
• Tribolium castaneum