들깨 잿빛곰팡이병의 생물학적 방제 II. 미생물농약의 제조 및 그 방제효과

An antagonistic bacteria, Bacillus licheniformis Nl strain which effectively inhibited mycelial growth of gray mold rot pathogen, Botrytis cinerea was isolated from the rhizosphere of perilla crop. Powder soy formulation by B. lichentfomis Nl strain as a biocontrol agent was developed far the first time and estimated its control effect on perilla leaves in this study. First of all, far the mass production of antifungal metabolites of B. lichentfomis Nl strain in flask liquid culture, the most effective carbon and nitrogen source were selected as glucose and tryp-tone, respectively, For the formulation, vegetative biomass of B. licheniformis Nl strain from 5-day-old liquid culture in nutrient broth added glucose and tryptone was mixed with soy flour, rice flour glucose, FeSo$_4$~7$H_2O$, and MnCl$_2$. 4$H_2O$, and dried and pulverized. In plastic house test, powder soy formulation effectually controlled gray mold rot as the control value of 93.1 %, was more effective than chemical fungicide, benomyl showing the control value of 86.1%. Thus, development of powder soy formulation of B. lichentfomis Nl will aid large-scale application of biological control in field trials. Botrytis cinerea에 의한 들깨 잿빛곰팡이병의 생물학적 방제를 위해 선발한 Bacillus lirheniformis Nl 글주를 제제화하여 미생물농약을 제조하고 이의 방제 효과를 검정하였다. Nl균주의 길항력에 미치는 탄소원과 질소원의 영향을 실험한 결과 탄소원으로는 glucose, 질소원으로는 tryptone이 가장 높은 효과를 보였다. 또한 Nl 균주를 이들 glucose와 tryptone을 첨가한 NB배지에 대량배양하고 그 배양액에 콩가루, 쌀가루, glucose, FeSo$_4$~7$H_2O$ 및 MnCl$_2$. 4$H_2O$ 을 첨가하여 수화형 미생물농약 Soy제제로제조하고,이 병원균에 대한 방제효과를 하우스내에서 폿트 검정한 결과 방제가가 93.1%로서 유의성은 없으나 베노밀 수화제에 의한 86.1%보다 높았다.