海南水稻上一种新病害的病原鉴定及室内药剂毒力测定

Pathogenic Identification of a Rice Disease in Hainan and Its Laboratory Test with Fungicides

近年来,海南水稻生产上出现一种类似稻瘟菌的病害,该病害分布广、危害严重,已经成为当地水稻生产的一个潜在威胁。本研究从海南不同地区水稻上分离到该病的病原菌,接种实验发现该分离物能引致与田间病害相同的症状。分生孢子形态鉴定和ITS序列分析表明,其为新月弯孢菌(Curvularia lunata)。杀菌剂室内抑菌实验结果表明,欧宝和凯润对其有较好的抑制作用。

A rice disease has occurred in recent years in Hainan with its symptoms similar to those of rice blast disease, and caused huge economic loss. The pathogen of the rice disease collected from different areas in Hainan was isolated. After inoculated with the isolates the young and adult plants of healthy rice showed the same symptoms as in the field. The morphological characteristics and the pathogenicity of these fungal isolates were studied. An ITS rDNA fragment of the fungi was amplified and the nucleotide sequences were tested and then analyzed using Megablast in GenBank. The results showed the pathogen was Curvularia lunata（Walker） Boedijn. Toxicity of 5 fungicides on mycelial growth of C. lunata was tested in laboratory. The results showed that Opal and Cabria could inhibit very well the mycelial growth of C. lunata.