Protection of Peach Trees from Bacterial Shot Hole with Bordeaux Mixture Spray during the Postharvest Season

복숭아 수확후 보르도액 살포에 의한 세균성구멍병 방제효과

This experiment was carried out to investigate the prevention of bacterial shot hole by Bordeaux mixture when it was sprayed on peach trees after harvest. bordeaux mixture was sprayed on \`Mibaeko\` peach trees 1 to 3 times after mid September, and the occurrence of bacterial shot hole was examined in the next year. Bacterial shot hole in leaves appeared from mid May and thereafter increased gradually. The more times was sprayed Bordeaux mixture, the less peaches were diseased with bacterial shot hole. At the beginning of August, the peach harvest time, the disease incidence of the untreated control plot was 27.4 to 38.1%, while the disease incidence was 9.7 to 31.8% when Bordeaux mixture was sprayed. The control value ranged from 16.5 to 64.6%. Occurrence of the fruit disease was similar to that of the leaf disease. Incidence of the fruit disease in the untreated control was 17.2 to 21.6%, but incase of the chemical treatment, it was 5.0 to 12.2 %, showing 41.9 to 70.9% of the control value. Chemical injury on peach leaves were not found in the 4-12 and 408 types, but occurred in some degrees in the 6-6 type of Bordeaux mixture.

복숭아 수확 후 보르도액의 살포효과를 구명하기 위하여 미백도 품종에 대해 9월 중순부터 1∼3회 살포한 후 이듬해 5월부터 세균성구멍병 이병율을 조사하였을 때, 보르도액 살포에 의한 방제효과는 살포횟수가 많을수록 높게 나타났다. 복숭아 수확기인 8월 상순의 경우 잎에서는 무처리구의 27.4%∼38.1%에 비해 보르도액 살포구에서는 9.7%∼31.8%의 이병율로 16.5%∼64.6%의 방제가를 보였고, 과실에서도 잎에서와 비슷한 경향이었는데 무처리구의 17.2%∼21.6%에 비해 41.9%∼70.9%의 방제가를 나타내었다. 보르도액 살포로 인한 약해는 6-6식 보르도액에서 2정도의 약해를 나타내었고, 4-12식 및 4-8식 보르도액에서는 약해가 없었으며, 복숭아 품종간에는 차이를 보이지 않은 경향이었다.