Entomopathogenic fungus, Beauveria bassiana can be used in integrated crop management and pharmaceutical applications. Recently some efforts have been given to the fungus to improve its biological performances, but low fungal transformation efficiency is one of the limitations. In this work, B. bassiana ERL1170 isolate was used for fungal transformation by restriction enzyme-mediated integration, where pBARKS1-Bbs-cecropinA was linearied using HindIII. The fungal transformation comprised two steps, preparation of competent blastospores and integration of the plasmid into the cells. To prepare competent blastospores, 2-d cultured blastospores were individually treated with 0.1, 0.2, 0.4 and 0.8 M lithium acetate (LiAc). Secondly in the integration step, concentration of LiAc and calcium chloride (CaCl2), and time period of heat shock were investigated as follows: LiAc, 1, 2 and 4 M; CaCl2, 50, 100 and 200 mM; and heat shock at 42℃, 20, 40 and 60 min. Consequently, combination of 0.2 M LiAc in preparing competent blastospores and 2 M LiAc and 200 mM CaCl2 in the second step showed the highest transformation efficiency. This work would be helpful in the fungal transformation of B. bassiana.

• Se Jin Lee(Deparment of Agricultural Biology, Chonbuk National University)
• Jeong Seon Yu(Deparment of Agricultural Biology, Chonbuk National University)
• Hee Won Yang(Deparment of Agricultural Biology, Chonbuk National University)
• Jong Cheol Kim(Deparment of Agricultural Biology, Chonbuk National University)
• Jae Su Kim(Deparment of Agricultural Biology, Chonbuk National University)