稻曲病菌的Nested PCR检测

为设计稻曲病菌(Ustilaginoidea virens)专化性PCR引物,测定了1991-2001年采集的多个水稻品种、不同水稻产区的菌株的ITS和5.8S rDNA区序列。U. virens的ITS1、ITS2和5.8S rDNA区域的长度为 624-625bp, 序列高度保守。在与麦角菌科其它种比较的基础上,设计了U. virens专化性嵌合引物。采用PCR方法可以灵敏地检测目标真菌,并且与传统的组织观察结果很好地吻合。这一结果为深入研究稻曲病的侵染规律和建立田间早期诊断技术提供了可能。

SPECIFIC AND SENSITIVE DETECTION OF THE FUNGAL PATHOGEN USTILAGINOIDEA VIRENS BY NESTED PCR

A 624-625 bp fragment of the inner space region of ITS and 5.8S rDNA of strains of Ustilaginoidea virens were sequenced, which collected from diverse rice varieties and geographical origins in different years in order to design PCR primers for its detection. Alignment of the sequence data of all collections revealed the ITS region of this pathogen was almost completely conservative. Based on the comparison with the ITS sequences of other Clavicipitaceous fungi, specific primers for U. virens were developed. The objective fungus was successfully detected with its specific primer set with high specificity and sensitivity, and the PCR results correlated well with assessments based on conventional technique of histological inspection. This result could provide a useful technique to study disease cycle and early prediction of field incidence of false smut.