中文摘要：

割手密是甘蔗杂交育种中重要的野生血缘供体亲本和抗逆性状基因源。选用根据植物抗旱和耐高温相关基因（DREB,Aquaporin;HSP70,WRKY1）设计的引物对或单条引物与随机引物之一组成的5对功能标记（DBF/Arb1,DBF/Arb2,Aqua/Arb1;SCB174,SCB190）对22份云南八倍体割手密进行抗逆功能标记的遗传多样性评价,同时选用13份甘蔗骨干亲本和10份近年云南主栽甘蔗品种作为对照。多态性统计显示,5对功能标记引物共获得113个条带,其中106个为多态性条带,17个为群体特异带,平均多态性条带比例为93.81%,平均多态信息量为0.914 0,八倍体割手密多态性表现最为丰富;遗传相似性系数分析表明,八倍体割手密无论在抗旱还是耐高温标记方面均有较大的相似性系数范围;群体遗传分化分析表明,八倍体割手密在抗旱和耐高温标记方面都与骨干亲本和主栽品种存在较小基因流,多数仅有30%左右的遗传变异来自于群体之间;UPGMA聚类结果也表明,云南八倍体割手密材料与骨干亲本和主栽甘蔗品种在5对抗逆功能标记上表现出明显的遗传差异。以上结果均表明,云南八倍体割手密在耐高温基因HSP70、WRKY和抗旱基因DREB、AQP等4个抗逆基因（尤其是HSP70和AQP）功能标记上较骨干亲本和近年云南主栽甘蔗品种拥有更为丰富的遗传变异,而且八倍体割手密中还有很多抗逆血缘未渗透到现代甘蔗品种中。因此,甘蔗品种改良上应加大云南八倍体割手密资源的利用力度。

英文摘要：

Saccharum spontaneum L. is a wild progenitor and donor species of resistance genes related to environmental stress in sug- arcane breeding programs. In order to know the genetic background of octoploid clones of S.spontaneum and utilize these wild clones more efficiently, five functional PCR markers, namely, DBF/Arbl, DBF/Arb2, Aqua/Arbl, SCB174, and SCB190, which were designed from stress resistance genes DREB, Aquaporin, HSP70 and WRKY1, or paired with arbitrary primer, were used to analyze the genetic diversity of 22 octoploid clones collected from Yunnan. Thirteen key parental lines and 10 major sugarcane cultivars of Yunnan were used as two control populations. The results showed that in total, 113 DNA bands were amplified, of which 106 were polymorphie. There were 17 bands that were population-specific. The mean value of percentage of polymorphie bands （PPB） was 93.81%. The mean value of polymorphism information content （PIC） was 91.40%. The octoploid clones showed the highest level of genetic polymorphism according to the PPB and PIC values. A wider range of Jaccard similarity coefficients was found among the oc- toploid clones using functional markers of both drought resistant and heat tolerant genes than among the key parental lines and major cultivars. Population genetic differentiation analysis indicated that the oetoploid S. spontaneum clones shared lesser gene exchanges with the two control populations, and only about 30% of the genetic variations were derived among groups. UPGMA clustering results also confirmed that the octoploid S.spontaneum clones exhibited obvious genetic divergence from beth control populations by all the five functional markers. Compared with beth control populations, the octoploid S.spontaneum clones from Yunnan possess much more abundant genetic variations for heat tolerance and drought resistance genes HSPTO, WRKY, DREB and AQP （especially HSP70 and AQP）. Much of these genetic variations have not been introgressed into the modern sugarcane cultivars. Therefore,