Lin Zhenyue, Wei Jingjing, Zhang Muqing, Xu Shiqiang, Guo Qiang, Wang Xin, Wang Jihua, Chen Baoshan, Que Youxiong, Deng Zuhu, Chen Rukai, Powell Charles A
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guanxi University, Nanning, Guanxi 530004, China; and College of Crop Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guanxi University, Nanning, Guanxi 530004, China.
Plant Dis. 2015 Mar;99(3):325-332. doi: 10.1094/PDIS-06-14-0661-RE.
Sugarcane twisted leaf disease, caused by Phoma sp., was first reported in Guangxi, China, in 2012, when more than 5% of sugarcane was infected in the field. Three single-spore isolates were recovered from symptomatic leaves. Sequences from five fungal loci, 28S nrDNA (LSU), 18S nrDNA (SSU), the internal transcribed spacer regions 1 and 2 and 5.8S nrDNA (ITS), β-tubulin (TUB), and the translation elongation factor alpha (TEF-α) were amplified from the disease-associated isolates. The twisted leaf disease pathogen was identified and formally described as Phoma sorghina var. saccharum through phylogenetic analyses, morphological observations, and the pathogenicity of the isolates on sugarcane. P. sorghina var. saccharum can be differentiated from related species based on the morphology of pycnidia and chlamydospores that formed regular, glabrous, papillate ostioles. Chlamydospore-anamorph was unicellular, botryoid-alternarioid shape, as well as the binucleate, frequently branched hyphae. We also showed that mycelial growth of P. sorghina var. saccharum was optimal at pH 4.0 and 20 to 25°C. Additionally, among 13 chemical compounds tested, carbendazim was found to be the most effective in suppressing the radial growth of the fungus. Mycelial growth in vitro was completely inhibited at concentrations of 100 and 50 ppm, and 87.6% of mycelial growth was inhibited at 10 ppm. Carbendazim is therefore a potentially effective fungicide to control this disease in China.
由茎点霉属（Phoma sp.）引起的甘蔗扭曲叶病于2012年在中国广西首次报道，当时田间超过5%的甘蔗受到感染。从有症状的叶片中分离出三个单孢分离株。从与病害相关的分离株中扩增出五个真菌基因座的序列，即28S核糖体DNA（LSU）、18S核糖体DNA（SSU）、内部转录间隔区1和2以及5.8S核糖体DNA（ITS）、β-微管蛋白（TUB）和翻译延伸因子α（TEF-α）。通过系统发育分析、形态学观察以及分离株对甘蔗的致病性，鉴定并正式描述了扭曲叶病病原体为高粱茎点霉甘蔗变种（Phoma sorghina var. saccharum）。高粱茎点霉甘蔗变种可根据形成规则、无毛、具乳头状小孔的分生孢子器和厚垣孢子的形态与相关物种区分开来。厚垣孢子无性型为单细胞，葡萄状-链格孢状，以及双核、常分枝的菌丝。我们还表明，高粱茎点霉甘蔗变种的菌丝生长在pH 4.0和20至25°C时最佳。此外，在测试的13种化合物中，多菌灵被发现对抑制该真菌的径向生长最有效。在100 ppm和50 ppm浓度下，体外菌丝生长完全受到抑制，在10 ppm浓度下，87.6%的菌丝生长受到抑制。因此，多菌灵在中国是控制这种病害的一种潜在有效杀菌剂。
