Phytopathology. 2007 Sep;97(9):1112-8. doi: 10.1094/PHYTO-97-9-1112.
ABSTRACT The Sigatoka disease complex of banana involves three related ascomycetous fungi, Mycosphaerella fijiensis, M. musicola, and M. eumusae. The exact distribution of these three species and their disease epidemiology remain unclear, because their symptoms and life cycles are rather similar. Disease diagnosis in the Mycosphaerella complex of banana is based on the presence of host symptoms and fungal fruiting structures, which hamper preventive management strategies. In the present study, we have developed rapid and robust species-specific molecular-based diagnostic tools for detection and quantification of M. fijiensis, M. musicola, and M. eumusae. Conventional species-specific polymerase chain reaction (PCR) primers were developed based on the actin gene that detected DNA at as little as 100, 1, and 10 pg/mul from M. fijiensis, M. musicola, and M. eumusae, respectively. Furthermore, TaqMan real-time quantitative PCR assays were developed based on the beta-tubulin gene and detected quantities of DNA as low as 1 pg/mul for each Mycosphaerella sp. from pure cultures and DNA at 1.6 pg/mul per milligram of dry leaf tissue for M. fijiensis that was validated using naturally infected banana leaves.
摘要 香蕉的叶斑病复合群涉及三种相关的子囊菌，即斐济球腔菌、M. musicola 和 M. eumusae。这三种物种的确切分布及其疾病流行病学仍不清楚，因为它们的症状和生命周期非常相似。香蕉球腔菌复合体中的疾病诊断基于宿主症状和真菌果实结构的存在，这阻碍了预防性管理策略的制定。在本研究中，我们开发了快速而稳健的基于分子的物种特异性诊断工具，用于检测和定量 M. fijiensis、M. musicola 和 M. eumusae。基于肌动蛋白基因开发了常规的物种特异性聚合酶链反应（PCR）引物，可分别从 M. fijiensis、M. musicola 和 M. eumusae 中检测到低至 100、1 和 10 pg/mul 的 DNA。此外，基于β-微管蛋白基因开发了 TaqMan 实时定量 PCR 检测方法，从纯培养物中每种 Mycosphaerella sp. 中检测到低至 1 pg/mul 的 DNA，从自然感染的香蕉叶片中验证了对 M. fijiensis 的检测，其 DNA 含量为每毫克干叶组织 1.6 pg/mul。
