초록
공주와 논산 육묘장에서 Pseudomonas syringae pv. syringae에 의한 세균점무늬병이 애호박에 심각한 피해를 주고 있지만, 점무늬병을 방제하기 위한 방제법이 개발되어 있지 않다. 종자처리와 방제약제를 선발하기 위하여 살균제 6종을 선택하여 병원균의 생장억제효과, 유묘에서 병 방제효과, 종자처리에 의한 병원균 및 병 방제효과를 각각 조사하였다. King's B배지에서 병원균 생장억제효과는 oxytetracycline 170 ppm, oxytetracycline 15 ppm + Streptomycin sulfate 188 ppm, oxolinic acid 200 ppm, streptomycin 200 ppm 처리 순으로 효과가 높게 확인되었다. Oxytetracycline 1.5% + streptomycin sulfate 18.8% WP와 oxytetracycline 17% WP의 유묘처리 시 방제가는 각각 71.4%, 49.4%이었다. Oxytetracycline 1.5% + streptomycin sulfate 18.8% WP를 인위적으로 감염된 종자에 처리하였을 때, 병원균의 생장을 완전히 억제하였으며, 유묘 발아실험에서 96% 방제효과를 나타내었다. Oxytetracycline 17% WP 2,000배 처리구에서 인위 감염 종자로부터 80 cfu/g의 병원균이 검출되었으며, 유묘발아실험에서 90%의 방제효과를 보였다. Streptomycin 20% WP의 2,000배액을 종자 처리하였을 때 병원균이 280 cfu/g으로 검출되었으며, 유묘발아실험에서 60% 방제효과를 나타내었다. 이러한 결과 oxytetracycline 1.5% + streptomycin sulfate 18.8% WP가 Pseudomonas syringae pv. syringae 에 의한 세균점무늬병의 방제와 종자처리를 위한 최적의 살균제로 판단된다.
Bacterial leaf spot, caused by Pseudomonas syringae pv. syrinage, is a very damaging disease to green pumpkin in Gong-ju and Non-san nursery. However, there is no good method to control the disease in Korea. Growth inhibition of pathogen on medium, control efficacy on seedling stage, and seed treatment effect of 6 anti-bacterial pesticides were investigated for selection of the best pesticide for seed treatment and control of the disease. Growth inhibition zone on King's B medium were the largest by oxytetracycline 170 ppm and oxytetracycline 15 ppm + streptomycin sulfate 188 ppm, oxolinic acid 200 ppm, streptomycin 200 ppm were next respectively. Control efficacy of oxytetracycline 1.5% + streptomycin sulfate 18.8% WP and oxytetracycline 17% WP on seedling stage were 71.4% and 49.4%, respectively. Seed treatment of oxytetracycline 15 ppm + streptomycin sulfate 188 ppm on the artificially inoculated seeds inhibits pathogen growth completely from the treated seeds and 96% control efficacy on grow-out test of the treated seeds. Seed treatment of streptomycin 100 ppm (2,000 dilution of streptomycin 20%) on the artificially inoculated seeds allow 280 cfu/g of pathogen growth from the treated seeds and 60% control efficacy on grow-out test of the treated seeds. Seed treatment of oxytetracycline 85 ppm (2000 dilution of oxytetracycline 17% WP) on the artificially inoculated seeds allow 80 cfu/g of pathogen growth from the treated seeds and 90% control efficacy on grow-out test of the treated seeds. These results suggested that oxytetracycline 1.5% + streptomycin sulfate 18.8% WP was the best pesticide for seed treatment to control of the bacterial spot disease by Pseudomonas syringae pv. syringae.
