Leaf mold caused by the fungus Cladosporium fulvum (syn. Passalora fulva) has been a serious disease in greenhouse tomatoes in Cuba, but less damage is seen in outdoor grown plants. This study was conducted to identify races of the causal agent of tomato leaf mold. A total of 36 single conidial isolates obtained from different provinces in Cuba and the reference strain race 0 were inoculated on a differential set of tomato cultivars carrying different Cf resistance genes. Further, a polymerase chain reaction (PCR) was developed using Avr9 gene-specific primers. As result, all isolates could overcome the Cf-9 resistance gene only, but not resistance genes Cf-2, Cf-4 and Cf-5 and must therefore be coined race 9. Race identity was also confirmed by PCR analysis, which showed that the Avr9 gene was not amplified in any of 36 single conidial isolates studied proving that they all lack this gene. This is the first report of the occurrence of race 9 of C. fulvum in Cuba. Pyramiding other Cf genes in hybrid of tomato may provide a more durable level of resistance to C. fulvum.

由真菌Cladosporium fulvum（同名Passalora fulva）引起的霉菌病在古巴的温室番茄中已成为严重的病害，但在室外种植的植物中危害较小。进行该研究以鉴定番茄叶片霉菌的病因。将来自古巴不同省份的36个单一分生孢子分离株和参考菌株0接种到不同的携带不同Cf抗性基因的番茄品种上。此外，使用Avr9基因特异性引物开发了聚合酶链反应（PCR）。结果，所有分离株只能克服Cf -9抗性基因，而不能克服Cf -2抗性基因， Cf -4和Cf -5，因此必须是第9种族。也通过PCR分析证实了种族同一性，这表明在研究的36个单分生孢子分离物中，Avr9基因没有扩增，证明它们均缺乏此基因。这是古巴发生C.fulvum第9种族的第一份报告。金字塔其他比照在番茄的杂合基因可以提供电阻的更耐用的水平C.黄枝孢霉。