新鉴定高抗TMV普通烟草枯斑资源的N导入片段长度多样性

为了解我国普通烟草（Nicotiana tabacum）资源对烟草花叶病毒（Tobacco mosaic virus，TMV）的抗性基因状况，为烟草抗病育种的亲本选择提供信息，利用N基因特异分子标记鉴定出携带N基因的普通烟草资源，并采用N导入片段的特异分子标记鉴定了N导入片段的长度。结果表明，供试的63份接种TMV表现枯斑的普通烟草（简称普通烟草枯斑资源）可划分为3大类型，分别为Coker176类型:GL3.50和GL4.06标记阴性、TN4.39、TN5.226、TN5.51标记阳性；Samsun NN类型:GL3.50、GL4.06、TN4.39、TN5.226标记阳性，TN5.51阴性；Xanthi nc类型:GL3.50、GL4.06、TN4.39、TN5.226、TN5.51标记阳性。402等51份资源的N导入片段长度属于Coker176类型，Ky160等2份资源的N导入片段长度属于Samsun NN类型。Ky52等10份资源的N导入片段长度属于Xanthi nc类型。N导入片段较短的枯斑资源，推测其连锁累赘可能较小，育种利用潜力较大。本文较系统地鉴定了普通烟草抗TMV的枯斑资源的N导入片段长度，可为抗TMV种质资源的育种利用提供参考。 

N introgression segment length polymorphism of newly tested Nicotiana tabacum germplasm highly resistant to tobacco mosaic virus

In order to understand the status of Nicotiana tabacum germplasm highly resistant to tobacco mosaic virus (TMV), to provide information for highly resistant parents selection in tobacco breeding, tobacco germplasm with N gene were selected by using N gene-specific molecular markers, and their N introgression segment lengths were tested by using N introgression segment specific molecular markers. Results showed that 63 tested tobacco germplasm could be divided into three main categories, Coker176 type:GL3.50 and GL4.06 marker negative, TN4.39, TN5.226, TN5.51 marker positive; Samsun NN type:GL3.50, GL4.06, TN4.39, TN5.226 marker positive, TN5.51 marker negative; Xanthi NC type:GL3.50, GL4.06, TN4.39, TN5.226, TN5.51 marker positive. The N introgression segment length of 402 and other 51 germplasm belonged to Coker176 type. The N introgression segment length of Ky160 and other 1 germplasm belonged to Samsun NN type. The N introgression segment length of Ky52 and other 9 germplasms belonged to Xanthi NC type. Germplasm with short N introgression segment may have less linkage drag, and are of greater breeding potential. The N introgression segment lengths of TMV highly resistant germplasm were evaluated in this paper, which could provide information for selecting highly resistant parents in variety development.