Occurrence of Gray Mold on Prunus mume Caused by Botrytis cinerea in Korea

Gray mold caused by Botrytis cinerea occurred on Prunus mume Sieb. & Zucc. in an experimetal orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea from 2005 to 2007. The symptoms usually started with water-soaking lesions and hollow depression on the fruit surface. The conidia of the pathogen appeared on the surface fruits. The conidia were one celled and mostly ellipsoid or ovoid in shape and were colorless or pale brown in color. The conidia were $6{\sim}17{\times}4{\sim}10{\mu}m$ in size and conidiophores were $15{\sim}30{\mu}m$ in length. The sclerotial formed abundantly on potato-dextrose agar, They were flat or irregular in shape and black in color The optimum temperature for sclerotial formation was $20^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea Persoon: Fries. This is the first report on gray mold of P. mume caused by B. cinerea by in Korea.

Botrytis cinerea에 의한 매실나무 잿빛곰팡이병 발생

2005년부터 2007년까지 경남농업기술원 과수포장에서 Botryitis cinerea에 의한 매실나무 잿빛곰팡이병이 발생하였다. 병징은 과실이 담갈색을 띄며 약간 함몰되면서 시간이 경과됨에 따라 대형으로 나타난다. 심하게 감염될 경우 부패되어지고 병반부위에 회색의 곰팡이가 많이 형성된다. 분생포자는 무색, 단포자이며 난형 또는 타원형으로 크기는 $6{\sim}17{\times}4{\sim}10{\mu}m$였고, 분생포자경 위에 분생포자가 많이 형성되었다. 분생포자경은 갈색으로 격막이 있고, 폭은 $15{\sim}30{\mu}m$였다. 균사생육과 균핵형성 적온은 $20^{\circ}C$였다. 병반에서 분리한 병원균의 균학적 특징을 조사한 결과 Botrytis cinerea Persoon: Fries에 의한 매실나무 잿빛곰팡이병으로 동정되었다.