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To isolate of antagonistic bacteria to Phytophthora capsici, which cause Phytophtora blight in red peper, 237 isolates of Pseudononas spp. and 260 isolates of Bacillus spp. were screened in selective media from rhizosphere soils of red Pepper at Kyongsan, Kyongju, Yongchon and Euisung in Kyongbuk. Among total 497 isolates, 8 isolates of Pseudononas spp and 4 isolates of bacillus spp. inhibited the mycelial growth of Phytophthora capsici above 50%. These antagonistic bacteria showed more inhibitory effect on TSA (tryptic soy agar) than V-8 juice agar. Four isolates, P0704, P1201, B1101, showing the most prominent antagonistic activity were selected and identified as P. cepacia (P0704, P1201), B. polymyxa (B1101) and B. subtilis (B1901), respectively. Cell free filtrates of these isolates were shown to inhibit zoosporangia germination and mycelial growth of P. capsici indication taht these isolates turned out to be bacteria producing antifungal substances. As a result of antagonistic test to Phytophthora blight in green house P. cepacia(P0704) showed the highest antagonistic effect with 46.7% and the rest of them were in the range of 13.4% to 26.7%.
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