오이 흰가루병 방제를 위하여 길항세균 B. amyloliquefaciens M27 균주의 배양액과 식물추출물(유카립투스)을 혼합한 새로운 혼합제를 만들어 실험하였다. 오이 흰가루병 방제를 위하여 병 발생 전과 직후부터 농도별로 처리한 효과를 조사한 결과, 500배의 희석배수로 처리할 경우가 우수한 효과를 보였다. 혼합제는 병 발생 후보다는 병 발생 전부터 예방위주로 처리하였을 때 방제효과가 높게 나타났다. 오이 흰가루병이 발생하기 전부터 5일 간격 4회, 7일 간격 3회, 10일 간격 2회 처리하였을 때 흰가루병이 각각 4.4%, 8.0%, 27.9% 발생하였고, 무처리구에서는 45.4% 발생하였다. 흰가루병 발생 후에는 5일 간격 4회, 7일 간격 3회, 10일 간격 2회 처리구에서 흰가루병이 각각 11.5%, 25.2%, 51.8% 발생하였고, 무처리구에서는 64.3% 발생하였다. 비닐하우스 포장에서 미생물 혼합제를 500배로 희석하여 5일 간격 2회 처리하였을 때가 7일 간격 3회 처리와 10일 간격 2회 처리하였을 때 보다 높은 방제효과를 나타내었다. 이상의 결과에서 M27균주와 유카립투스 추출물을 혼합한 혼합제는 오이 흰가루병 방제용 미생물제의 유망한 후보가 될 수 있을 것으로 생각한다.
Bacillus amyloliquefaciens M27 was selected as a control agent for the biological control of cucumber powdery mildew. The new mixture of B.amyloliquefaciens M27 and plant (Eucalytus) extract was developed to improve the control activity of B.amyloliquefaciens M27 against cucumber powdery mildew. The mixed formulation showed the high preventive and curative control effect against cucumber powdery mildew when it was diluted at 500 times and foliar-sprayed. Its control effect was higher in preventive spraying than curative spraying. When 500-fold diluted solution of the formulation was sprayed preventively four times at five-day intervals, three times at seven-day intervals and twice at ten-day intervals, the diseased leaf area was shown to be 4.4%, 8.0%, 27.9%, respectively; Whereas the diseased leaf area in the control plot was 45.4%. When the 500-fold diluted formulation was sprayed curatively four times at five-day intervals, three times at seven-day intervals and twice at ten-day intervals after occurred cucumber powdery mildew, the diseases leaf area was 11.5%, 25.2%, 51.8%, respectively; whereas in the control plot, the diseases leaf area was 64.3%. When the 500-fold diluted formulation was treated four times at five-day intervals in the plastic house, its control effect was higher than that treated three times at seven-day intervals and twice at ten-day intervals. As the results, the mixed formulation of B.amyloliquefaciens M27 and plant extract could be a promising candidate of bio-fungicides for the environment-friendly control of powdery mildew of cucumber.
