Al-Subhi Ali M, Al-Adawi Ali O, Van Wyk Marelize, Deadman Michael L, Wingfield Michael J
Department of Crop Sciences, Collage of Agricultural and Marine Sciences, Sultan Qaboos University, P.O. Box 34, Al-Khod 123, Sultanate of Oman.
Mycol Res. 2006 Feb;110(Pt 2):237-45. doi: 10.1016/j.mycres.2005.08.007. Epub 2005 Nov 7.
Mango (Mangifera indica) sudden decline is an important disease in Oman, which is closely associated with infections by Ceratocystis fimbriata and Lasiodiplodia theobromae. Another Ceratocystis species has also been found associated with symptoms on diseased trees. In this study, we identify that Ceratocystis based on morphology and DNA sequences. Morphological comparisons showed that the fungus from dying mango trees in Oman is similar to C. moniliformis. Both fungi have distinct hat-shaped ascospores, disc-shaped plates at the bases of the ascomatal necks and spines on the ascomatal bases. However, comparison of DNA sequences for ITS1-2, the 5.8S RNA gene, the beta-tubulin gene, and Transcription Elongation Factor (EF1-alpha) gene, confirmed that the fungus from Oman is distinct from C. moniliformis and other related species. Phylogenetically, this fungus formed one of four strongly supported sub-clades. The other sub-clades included isolates of C. bhutanensis, C. moniliformis and C. moniliformopsis, respectively. Based on morphological characteristics and differences in DNA sequences for three gene regions, we conclude that the Ceratocystis sp. from wounds on mango in Oman is a new species, for which we provide the name Ceratocystis omanensis sp. nov.
芒果（芒果属印度种）突然衰退病是阿曼的一种重要病害，与帚状炭疽菌和可可毛色二孢菌的感染密切相关。还发现另一种炭疽菌与患病树木的症状有关。在本研究中，我们基于形态学和DNA序列鉴定炭疽菌。形态学比较表明，阿曼垂死芒果树上的真菌与念珠状炭疽菌相似。两种真菌都有独特的帽状子囊孢子、子囊颈部基部的盘状板以及子囊基部的刺。然而，对ITS1-2、5.8S rRNA基因、β-微管蛋白基因和转录延伸因子（EF1-α）基因的DNA序列比较证实，阿曼的真菌与念珠状炭疽菌和其他相关物种不同。在系统发育上，这种真菌形成了四个得到有力支持的亚分支之一。其他亚分支分别包括不丹炭疽菌、念珠状炭疽菌和拟念珠状炭疽菌的分离株。基于形态特征和三个基因区域DNA序列的差异，我们得出结论，阿曼芒果伤口上的炭疽菌是一个新物种，我们将其命名为阿曼炭疽菌（Ceratocystis omanensis sp. nov.）。
