Seasonal Occurrence and Infection Site of Strawberry Anthracnose

Seasonal occurrence of strawberry anthracnose in greenhouses caused by Colletotrichum sp. was examined from 1997 through 1999 at three locations, Kyeongju, Goryeong, and Cheongdo in Kyungbuk province, Korea. Also some factors related to the anthracnose infection such as initial infection sites, inoculation methods, and soil nature were studied through in vitro and field experiments. The anthracnose disease begun to occur from 15 days after transplanting in early October, and continued but gradually decreased thereafter for 2 months until December, After transplanting, initial infection mainly occurred through the runner of which the tissue was more susceptible to the anthracnose than those of the leaf and petiole when the fungal mycelial disk was inoculated. Postplanting inoculation by irrigation with spore suspension was much more effective in inducing the anthracnose disease than preplanting soil mix. However without inoculation, no or little anthracnose occurred regardless of commercial, non-cultivated or diseased field soils when healthy seedlings were planted. This suggests that occurrence of strawberry anthracnose in fields may be related to contamination of plant propagules with the anthracnose pathogen.

딸기탄저병의 시기별 발생과 감염경로

딸기탄저병의 발병특성은 정식 직후 격발하다가 시간이 지날수록 발병율이 감소하였으며, 11월 이후에는 발병이 감소하였다. 정식 직후에는 주로 런너로 침입하였으나 엽병 제거 후는 제거한 상처부위로 주로 침입을 하였다. 식물체의 부위별로는 런너에서 가장 강한 병원력을 보였으며 접종방법별로는 생장점 부위로 관주를 할 경우 가장 발병율이 높았다. 딸기탄저병에 의해 고사된 포기를 제거한 자리에 건전한 포기를 심었을 경우 옮겨 심은 포기에서는 발병이 되지 않았다.