Production of Bacillus thuringiensis biopesticide using penicillin fermentation waste matter and application in agriculture
Song Gun Choe, Hang Ryol Maeng, Song Jin Pak, Song Nam U
Abstract
Bacillus thuringiensis (Bt) has been widely used in pest control, but the large scale production of this biopesticide is expensive because of the high cost of the medium and production method. In this study, we attempted to use inexpensive penicillin fermentation waste matter for the growth of Bacillus thuringiensis. The penicillin fermentation waste samples were used under conditions: without pre-treatment, with Na2CO3 treatment, with acetic acid treatment and with drying treatment. The penicillin fermentation waste matter with Na2CO3 treatment gave the highest cell counts. A maximum spore count (24.5 ×108cfu/ml) was obtained by cultivating B. thuringiensis 2387 in medium containing 5% penicillin fermentation waste matter. Insecticidal potency of Bacillus thuringiensis biopesticide(Bt insecticidal concentrate) was about 8 000IU/㎎. Bt insecticidal concentrate showed 77–90% insecticidal efficacy against Pieris rapae, Plutella xylostella and Heliothis virescens in the field trial.