Red Spot of Broad Bean (Vicia faba) Caused by Botrytis fabae

Red spot disease was found on broad bean (Vicia faba) in several farmer's field located in Changseon-myon, Namhae-gun, Gyeongnam provice in Korea. The typical symptoms of the disease were appeared on leaves and stems. The infection rates of the disease in the surveyed area were ranged from 16.4 to 84.6%. Lesions on the leaves were round with 1~4.2 mm in size and on the stem were narrow long fusiform with 1~15 mm in size. Conidia and conidiaphores were not readily farmed on PDA, however, a few conidia were formed on PDA added in extracts of 10 g of broad bean leaves. Conidia were light yellow green in color, globose or obovoid in shape, and 10~24$\times$8~22 $\mu$m in size. Conidiophores were cylindrical in shape, light brown in color and 3.6~12.8 $\mu$m in wide. Sclerotia of the fungus were readily formed in artificial media such as PDA. They were ellipsoid to irregular in shape, 1.2~11.8 mm in size and dark in color, The optimum temperature far growth of the fungus was about 2$0^{\circ}C$. On the basis of mycological characteristics, the fungus was identified as Botrytis fabae. This is the first report on the red spot of broad bean caused by Botrytis fabae in Korea.

Botrytis fabae에 의한 잠두 붉은점무늬병

2001년 경상남도 남해군 창선면 잠두 재배포장에서 잎과 줄기에 붉은점무의 병이 심하게 발생하였다. 이 병의 병징은 잎에 원형의 붉은점무늬가 많이 생기고 병반의 크기는 1~4.2mm이며, 줄기에는 가늘고 긴 방추형 모양의 병반이 생기고 크기는 1~l5mm이었다. 포장에서 발생율은 16.4~84.6%이 었다. 분생포자와 분생포자병은 PDA배지 상에서 잘 형성되지 않았으나, PDA배지에 잠두 잎 추출액을 첨가하였을 때는 보다 양호하게 형성되었다. 분생포자는 원형 또는 난형이며 담황록색고 크기는 10~24$\times$8~22 $\mu$m 이었다. 분생포자병은 원통형, 담갈색이고 크기는 3.6~12.8 $\mu$m이었다. 균사생육은 적온은 2$0^{\circ}C$에서 균핵 형성은 15$^{\circ}C$-2$0^{\circ}C$에서 가장 잘 형성하였고, 검은색이고 구형 또는 부정형이며, 균핵의 크기는 1.2-11.8mm였다. 병원균의 균학적 특징과 병원성을 검정한 결과 이 병을 Botrytis fabae에 의한 잠두 붉은점무늬병으로 명명하고자 제안한다.