利用伏马毒素合成基因对玉米种子寄藏镰刀菌的分子检测

我国玉米种子普遍受到拟轮生镰刀菌(Fusarium verticillioides)的侵染,该菌产生的伏马毒素对国家种质库中玉米种质的安全保存有着潜在的影响。fum1基因是F.verticillioides等镰刀菌中伏马毒素生物合成的必需基因。选用3对已知引物Fum5F/Fum5R、P1/P2和P3/P4分别对从玉米种子中分离出的9株镰刀菌和1株阴性对照菌链格孢菌进行PCR扩增检测,在F001和F003菌株中扩增出相应的特异性表达片段。测序表明,这些片段的长度分别为846bp、888bp和703bp,与已知fum1基因(AF155773)的同源性达99%以上。3对引物的检测灵敏度达到88pg/mL。结果表明,这3对引物都能够有效地检测产生伏马毒素的镰刀菌菌株,但引物Fum5F/Fum5R所扩增片段完全来自fum1基因内部,具有更强的特异性。在此定性检测基础上,需要进一步研究定量检测方法并进一步研究伏马毒素对农作物种质保存的影响。

Molecular detection of Fusarium strains producing fumonisins in maize seeds

In this study,three pairs of previously published primers,Fum5F/Fum5R,P1/P2 and P3/P4,were used to detect FB in nine Fusarium strains.In strain F001 and F003,846 bp,888 bp and 703 bp fragments were amplified by Fum5F/Fum5R,P1/P2 and P3/P4,respectively,which were then sequenced.The nucleotide sequences of the three segments amplified from both strains were compared with the fum1 sequence retrieved from GenBank(acc.no.AF155773).The results demonstrated that they had a high identity(>99%).The detection sensitivity was 88 pg/L with the three primers.The results showed that all of the three primers could be used to effectively detect Fusarium strains producing fumonisins.And Fum5F/Fum5R was the best pair because the product amplified was completely from within the gene fum1.