小孢子链格孢的IGS-RFLP分析

用基因间隔区特异性引物对10个小孢子链格孢种和作为对照的1个大孢子链格孢种(茄链格孢)(Al-ternaria solani)进行扩增,小孢子链格孢种获得约3.0kb片段,而大孢子链格孢种获得约4.0kb片段,大孢子种和小孢子种可通过IGS扩增片段明确区分.分别用限制性核酸内切酶HaeⅢ和MspⅠ对小孢子链格孢的扩增产物进行限制性酶切,可产生不同的酶切图谱.根据酶切图谱可以把细链格孢和细极链格孢区分.IGS扩增产物表现出长度和序列结构上的多态性,是一个良好的遗传标记,对于一个种内的不同菌株具有一定鉴别意义,但是由于利用现有引物一些菌株难以扩增出PCR产物,该方法的利用受到一定限制.

IGS-RFLP of small-spored Alternaria

Intergenic spacer was amplified with specific primers to analysis the small-spored species and big-spored(Alternaria solani)species.The small-spored ones could produce a single band about 3.0kb,while A.solani could produce a 4.0kb band,so the small-spored species and big-spored species could be distinguished easily by products of IGS.The PCR products were digested with restriction endoenzyme HaeⅢand MspⅠrespectively,and different patterns were obtained from each enzyme,by combining the restriction patterns of two enzymes,Alternaria alternataand Alternaria tenuissimacould be differentiated from each other.IGS displayed polymorphism in the length and the sequence structure,it could be treated as a good genetic marker and significant to identify kinds of different strains.For some isolates could not get PCR products,so its applying value is limited.