Investigation on favorable conditions for mycelial growth of Paecilomyces tenuipes

눈꽃동충하초(Paecilomyces tenuipes)의 균사생장조건 구명

Distribution and in vitro growth characteristics of entomopathogenic Paecilomyces species were studied based on the specimens and isolates deposited in Entomopathogenic Fungal Culture Collection (EFCC), Kangwon National University, Chuncheon, Korea. Paecilomyces species were frequently collected from different mountains and valleys and were almost distributed uniformly. Collection period of Paecilomyces species ranged from July to September, with most of the collections at the end of September. P. tenuipes was mostly collected one among different Paecilomyces species. The optimum medium for mycelial growth of P. tenuipes was PDA, whereas in other media such as SDAY and HMA also produced similar growth. The optimum temperature and pH levels were $25^{\circ}C$ and 6.0~7.0, respectively. Best carbon and nitrogen sources were dextrose and tryptone, respectively, while $KH_2PO_4$ was the best mineral source for mycelial growth. Highest mycelial growth was observed when the C/N ratio was 20:1.

본시험은 한국에서 채집되어 강원대학교 동충하초은행(EFCC)에서 보관 중인 눈꽃동충하초의 분포와 배양적 특성을 조사하였다. 눈꽃동충하초는 한국의 산이나 계곡에서 어렵지 않게 채집할 수 있으며 골고루 분포한다. 채집시기는 7~9월로 나타났으며 9월말에 가장 많이 채집할 수 있으며 채집된 눈꽃동충하초의 종은 눈꽃동충하초(P. tenuipes)가 가장 높게 채집되었다. 눈꽃동충하초의 균사배양 최적배지는 PDA배지이며 SDAY와 HMA배지에서도 생장은 가능하며 균사생장에 가장 적합한 온도는 $25^{\circ}C$이며 pH는 6.0~7.0으로 나타났다. 적합한 영양원으로는 탄소원은 dextrose이었으며, 질소원은 tryptone가 가장 우수하였고, 무기염으로는 $KH_2PO_4$에서 가장 고른 성장을 보였다. C/N에서는 20 : 1의 비율이 가장 적합한 것으로 조사되었다.