Gray Mold of Safflower Caused by Botrytis cinerea

Botrytis cinerea에 의한 잇꽃 잿빛곰팡이병

The gray mold disease was severely occurred on safflower grown in experimental farm of Kyongsangnam-do Agricultural Research and Extension Services in 1999. At first, the infected leaves discolored gray or dark from the tip and gradually expanded to downword. The fungus also attacked stem, pod and calyx. The infected area became dark and dried, and frequently gray mold grown on the infected area. The causal organism was isolated and proved its pathogenecity according to Koch's postulate. Conidia of the fungus in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized $7.4{\sim}16.8{\times}5.3{\times}10.4\;{\mu}m$. Conidiophores were observed with their wide size of $2.9{\times}15.5\;{\mu}m$. The temperature range for mycelial growth was between $5^{\circ}C\;and\;30^{\circ}C$ with the optimum temperatures of $20^{\circ}C\;and\;25^{\circ}C$. The causal organism was identified as Botrytis cinerea and based on mycological characteristics examined. This is the first report on gray mold of safflower caused by Botrytis cinerea in Korea.

1999년 5월 경상남도농업기술원 잇꽃 재배포장에서 잎, 줄기, 꼬투리, 꽃받침에 잿빛곰팡이병이 발생하였다. 병징은 처음 잎, 줄기, 고투리와 꽃받침 끝부분이 암갈색으로 변하고 나중에 회갈색의 병징이 나타나다가 결국 고사하며 그 부분에 잿빛곰팡이가 아주 많이 형성한다. 분생포자는 무색, 단포자이며 난형 또는 타원형으로 크기는 $7.4{\sim}16.8{\times}5.3{\sim}10.4;{\mu}m$였고, 분생자경 위에 분생포자가 아주 많이 형성되었다. 분생자경은 갈색으로 격막이 있고 폭은 $2.9{\sim}15.5\;{\mu}m$였다. 균사생육 온도는 $5^{\circ}C$에서 $30^{\circ}C$이며 적온은 $15^{\circ}C$에서 $25^{\circ}C$이었다. 병반에서 분리한 병원균은 Botrytis cinerea에 의한 잇꽃 잿빛곰팡이병균으로 동정되었다.