【摘要】 小麦茎基部可寄居多种真菌,并可导致发褐、坏死等症状,与小麦纹枯病相混淆。为准确诊断小麦纹枯病,根据江苏省小麦茎基部常见寄居菌禾谷丝核菌 Rhizoctonia cerealis、立枯丝核菌 Rhi-zoctonia solani、长蠕孢菌 Helminthosporium spp.、交链孢菌 Alternaria spp.、小麦全蚀病菌 Gaeumanno-myces graminis var.tritici 和禾谷镰刀菌 Fsarium graminearum rDNA 的 ITS 区段序列差别,设计合成了2对特异性扩增引物(DNF77+DNR554,DNF81+DNR564)用于小麦纹枯病菌检测。2对引物均能从小麦纹枯病菌株扩增到特异性的分子片段,说明设计的特异性引物可以用来检测小麦纹枯病菌。采集田间具有小麦纹枯病症状、茎基部变褐及健康麦苗,进行病原菌分离,同时提取这些麦苗茎基部 DNA,利用上述2对引物进行扩增。结果表明,仅从能分离到禾谷丝核菌的麦组织中扩增到约480bp 的特异性条带。说明设计的特异性引物可以对田间小麦纹枯病进行早期、快速分子诊断。更多还原

【Abstract】 According to the difference of rDNA ITS sequence among Rhizoctonia cerealis,Rhizoctonia so- lani,Helminthosporium spp.,Alternaria spp.,Caeumannomyces graminis var.tritici and Fusarium gra- minearum,which usually inhabits bases of wheat plants,two pairs of primers,DNF77+DNR554 and DNF81+DNR564,were designed to detect Rhizoctonia cerealis which cause wheat sharp eyespot.The re- sults showed that a sequence about 480bp could be amplified by PCR from pure cultured R.cerealis iso- lates and infected sheath of wheat by R.cerealis isolates using the designed primers,which could be used to develop a rapid PCR-based diagnostic technique for the sharp eyespot at early stage of R.cerealis infec- ting wheat.更多还原