小麦和玉米籽粒赤霉菌产毒类型的PCR检测

为了建立一种准确、快速鉴定赤霉菌毒素的方法,根据赤霉菌毒素生物合成调控路径T ri5-T ri6基因保守序列,设计了一对通用引物,用于检测和鉴别产生脱氧雪腐镰刀菌烯醇(DON)和雪腐镰刀菌烯醇(N IV)毒素的赤霉菌特异DNA片断。结果表明,产生毒素DON的赤霉菌具有一个300 bp的特异DNA片断,而产生毒素N IV的则为360 bp。PCR检测与HPLC或GC/M S化学分析结果完全一致。利用这一方法分析检测了小麦、玉米籽粒中赤霉菌产毒类型,发现除健康籽粒外,在所有轻微、中度、严重感染赤霉病的小麦或玉米籽粒中,均同时检测到DON及N IV的两种DNA片断,表明这一对通用引物对两种毒素特异DNA片断的扩增效率相同。这些结果说明,该技术是一种经济、快速、可靠的PCR检测技术,可广泛用于赤霉菌及其毒素检测鉴定中。

PCR Identification of Mycotoxin-chemotypes from Grains of Wheat and Maize Associated with Head Blight

To develop a rapid and accurate method for the identification of mycotoxin-chemtypes from Fusarium head blight (FHB), a pair of primers was designed based on the conserved sequences of Tri5-Tri6 genes involved in the biosynthesis of Fusarium mycotoxins, which could detect the DNA fragments specific for mycotoxin-chemotypes deoxynivalenol (DON) and nivalenol (NIV). The results indicated that a 300 bp fragment from DON-chemotypes and a 360 bp fragment from NIV-chemotypes were amplified. The mycotoxin-chemotypes identified by PCR were confirmed by chemical analysis of HPLC or GC/MS. Further analyses showed that both DON-and NIV-specific DNA fragments were simultaneously amplified from the grains of wheat and maize with a light, intermediate or severe symptom of FHB, whereas no PCR product was detected in healthy grains, indicating that the PCR assay is a cost-effective, rapid and reliable method, and could efficiently amplify fragments from two mycotoxin-chemotypes. This PCR assay could be widely used in detection of DON-and NIV-mycotoxin chemotypes for plant quarantine and the safety controls of food and livestock.