An application No. 1627/DEL/2008 dated July 8, 2008 entitled “A process for the mass production of Bacillus thuringiensis (Bt) biocide using millet grain based agro-medium” invented by ICAR-VPKAS, Almora has been granted patent No. 336230. The inventors of this mass production of Bt. are M. Mohan, S.N. Sushil, J.C. Bhatt, S. Saha, H.S. Gupta and J. Stanley.
The invention employs cost effective high yielding agro based growth medium for the early, profuse sporulation and the process for the mass production of bio-insecticide, Bacillus thuringiensis. The millet based agro based medium comprised of finger millet grain powder; defatted soybean, etc. This medium is supplemented with solid media with crop wastes to make it solid for mass production. The media described in this present invention is suitable for the efficient mass production of Bt spore-crystal toxin used for the management of insect pests.
The invention discloses a process for preparation of biocide using a cold tolerant/environmentally competitive and highly entomopathogenic isolate (strain VLBt 6) of Bacillus thuringiensis subsp. galleriae/colmeri (MTCC 8997) isolated from the North-Western Himalaya. The strain is highly entomopathogenic and capable of producing larger quantity of delta- endotoxin (crystal toxin) with broad range as well as enhanced pesticidal/insecticidal activity. Further, the strain is found highly insecticidal against diamondback moth Plutella xylostella, cabbage butterfly Pieris brassicae, cabbage semiloopers Thysanoplusia ni and T. orichalcea, cabbage leaf webber Crocidolomia binotalis, amaranth leaf webber Hymenia recurvalis and tomato fruit borer Helicoverpa armigera etc. The biocide is found quite toxic to the specific target insects, but is harmless to plants and other non-targeted organisms. Furthermore, it is cold tolerant and thus tends to sporulate even at low temperature.
The solid and liquid media (VLBt S and VLBt L) and the production process described here are conveniently suitable for the efficient mass production of spore delta endotoxin (crystal toxin) from many Bt strains at village or farmer’s household level at small entrepreneurs level as well as at industries level using big fermenters and other downstream processing equipments. The process of the present invention makes use of locally, abundantly available agro-industrial by-products thereby significantly reducing the overall cost of technology in addition to providing environmentally safe technology. The media described in the present invention do not require addition of many mineral salts for induction of sporulation. The external adjustment of media pH is also not required at any stage of the fermentation process. The present invention also provides a composition of formulation containing the biocide preferably delta endotoxin as an active ingredient and conventional acceptable carrier.