MacKenzie S J, Mertely J C, Seijo T E, Peres N A
University of Florida, Gulf Coast Research and Education Center, Wimauma 33598.
Plant Dis. 2008 Oct;92(10):1432-1438. doi: 10.1094/PDIS-92-10-1432.
Evidence that Colletotrichum fragariae causes disease on hosts other than strawberry is limited. In the fall of 2006, fungal isolates from silver date palm with leaf spot symptoms and from cyclamen with leaf spot and stem rot symptoms were identified as C. fragariae. After confirming the pathogenicity of the isolates on their host of origin, a representative isolate from each host was compared to C. fragariae and to C. gloeosporioides/Glomerella cingulata isolates from strawberry. Date palm and cyclamen isolates bore conidia on setae, and conidia were tapered and in the size range of C. fragariae reference isolates. Sequence data from the combined internal transcribed spacer (ITS) regions 1 and 2 and the gene for the 5.8 ribosomal RNA from the cyclamen and date palm isolates matched the sequence for C. fragariae reference isolates. Based on these characteristics, it was concluded that the C. fragariae species designation was correct for both isolates. However, the date palm isolate was a weak pathogen on strawberry compared with other isolates and had a distinct AT-rich DNA banding pattern. The ability of the cyclamen isolate to cause crown rot on strawberry was comparable with the strawberry reference isolates, and the AT-rich DNA banding pattern of the cyclamen isolate was identical to the C. fragariae isolates from strawberry. The results indicate that C. fragariae is a pathogen on hosts other than strawberry and that there is more diversity among C. fragariae isolates than previously reported.
草莓炭疽菌在草莓以外的寄主上引发病害的证据有限。2006年秋季，从出现叶斑症状的银枣椰树以及出现叶斑和茎腐症状的仙客来上分离得到的真菌菌株被鉴定为草莓炭疽菌。在确认这些分离菌株对其原始寄主的致病性后，将来自每个寄主的一个代表性菌株与草莓炭疽菌以及从草莓上分离得到的胶孢炭疽菌/围小丛壳菌菌株进行了比较。枣椰树和仙客来分离菌株在刚毛上产生分生孢子，分生孢子呈锥形，大小在草莓炭疽菌参考菌株的范围内。来自仙客来和枣椰树分离菌株的内部转录间隔区（ITS）1和2以及5.8核糖体RNA基因的序列数据与草莓炭疽菌参考菌株的序列相匹配。基于这些特征，得出结论，这两个分离菌株的草莓炭疽菌物种命名是正确的。然而，与其他分离菌株相比，枣椰树分离菌株在草莓上是一种弱病原菌，并且具有独特的富含AT的DNA条带模式。仙客来分离菌株在草莓上引起冠腐病的能力与草莓参考菌株相当，并且仙客来分离菌株的富含AT的DNA条带模式与从草莓上分离得到的草莓炭疽菌菌株相同。结果表明，草莓炭疽菌是草莓以外寄主上的病原菌，并且草莓炭疽菌分离菌株之间的多样性比之前报道的更多。
