拟三属间杂交品系神农高糖蔗种质来源鉴定

Identification of a Putative Trigeneric Hybrid Shennong Gaotangzhe for its Germplasm Origin

新品种选育的关键在于优异种质资源的创制和利用,远缘杂交是创新种质的重要手段。近年来,有机构宣称培育了一种由高粱、玉米、甘蔗属间杂交而成的神农高糖蔗新品系。为了准确地鉴定其种质来源,本研究利用形态学、SCo T标记和GISH技术对神农高糖蔗进行了研究。形态学初步鉴定结果表明:从根、茎、叶等不同器官的形态特征来看,神农高糖蔗与甘蔗、玉米、高粱都具有较多相似之处,无法准确地甄别出神农高糖蔗是否为真杂种。根据SCo T标记的聚类结果,可以将12份供试材料分成I、II、III 3大类,I类包括3份高粱材料和神农高糖蔗,6份甘蔗材料均聚为II类,2份玉米材料聚为III类。在整个聚类图中神农高糖蔗和非洲甜高粱的相似系数最大,说明神农高糖蔗与非洲甜高粱的遗传距离较小,它们之间存在较小的遗传差异。比较基因组原位杂交结果表明,神农高糖蔗只含有甜高粱的血缘,而不含有甘蔗和玉米的血缘。本研究结合3种鉴定方法,可以基本确定神农高糖蔗并非甘蔗、高粱和玉米的属间杂种,而是甜高粱的一个品系(品种)。本研究结果不仅揭露了虚假报道,避免不必要的损失,还探讨了甜高粱作为甘蔗远缘杂交种质资源的利用前景。

Improvement and innovation of germplasm resources are the keys of breeding new cuhivars, and the distant hybridization is an important way in improving germplasm. A new variety named ＇ Shennong has been promoted in recent years, which is declared as a hybrid of Sorghum, maize and sugarcane. In Gaotangzhe ＇ order to iden- tify the real germplasm sources of ＇Shennong Gaotangzhe ＇,we used morphology,SCoT markers and GISH technology to analyze the possible genetic origin of ＇ Shennong Gaotangzhe ＇ in this study. Among them, the results of prelimina- ry identification of morphology indicated that ＇ Shennong Gaotangzhe ＇ was very similar to sugarcane, maize and sor- ghum only based on the characteristics of roots, stems,leaves and other organs, so it was unable to accurately distin- guish ＇ Shennong Gaotangzhe ＇ for true hybrids. According to the cluster results of SCoT markers, 12 tested materials could be divided into three categories named I, II and III, the category I included three kinds of Sorghum and the ＇ Shennong Gaotangzhe ＇, the six tested materials of sugarcane belonged category II, and the two kinds of maize be- longed category III. From the cluster diagram sorghum was the largest. It showed that the ge , the similar coefficient of ＇ Shennong netic distance between ＇Shennong Gao Gaotangzhe＇ and African sweet tangzhe ＇ and African sweet sor- ghum was closer and the genetic differences was smaller than the others. The results of comparative-GISH revealedthat ＇ Shennong Gaotangzhe ＇ shared a common ancestor with or maize. Combined with the three methods identified in this sweet sorghum, but without the descendant of sugarcane study,the ＇ Shennong Gaotangzhe ＇ was identified as a variety （line） of sweet sorghum, but not a hybrid of sugarcane, sorghum and maize. The results of the study not only reveal the false reports for avoiding unnecessary losses, but also explore the prospect of sweet sorghum as a germ- plasm resource of sugarcane for distant hybridization.