유기농 감자재배지에서 감자역병에 의한 병 진전 및 수량감소 |
류경열, 지형진, 최두회, 천정욱, 김종태, 김병섭 |
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Disease Progress and Yield Loss of Potato Late Blight Caused by Phytophthora infestans in Organic Farming Fields |
Kyoung Yul Ryu, Hyeong Jin Jee, Du Hoi Choi, Jeong Uk Cheon, Jong Tae Kim, Byung Sup Kim |
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Abstract |
Late blight of potato caused by Phytophthora infestans is one of the most destructive disease in organic farming as well as in the conventional cultivation in Korea. Incidence and progress of the disease largely depend on climatic conditions around the fields. However, the disease completely destroys whole leaves of the plant within two weeks in organic farming fields. While, potato leaves in conventional farming fields remain healthy for 5 weeks after the first symptom appearance, because fungicides were applied four times in average to control the disease. Area under disease progress curve (AUDPC) of organic farming fields ranged from 2314 to 2421 and quickly expanded compare to that of conventional farming fields. The tuber yield in the organic farming fields ranged from 0.96 ton per 10a to 1.5 ton per 10a, while it was 2.7 ton per 10a in conventional farming fields. Tuber yields were reduced to 42~63% by the infection of late blight and the reduction rate was closely related with the time of first occurrence of the disease in organic farming fields. Physiological races of the pathogen were diversified with R0,1,3,4,5,7,10,11 in organic farming fields at Hongchun area. Pathogen races were distributed with similar pattern at different areas of organic farming fields. |
Key Words:
Disease progress, Organic farming, Phytophthora infestans |
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