中国十倍体割手密资源抗逆功能标记的遗传多样性分析

Genetic Diversity of Decaploid Saccharum spontaneum L. in China According to Functional Markers Related Stress Tolerance

整倍体割手密是现代甘蔗品种重要的野生亲本和抗逆性状基因源,为了明确其抗逆相关基因的遗传背景,该研究选用来自脱水绑定因子DREB、水通道蛋白AQP、热激蛋白HSP70、WRKY1转录因子和随机引物组成的5对抗旱和耐高温相关功能标记,以63份甘蔗常用亲本材料和8份甘蔗原种作为对照,对中国保育的50份十倍体割手密（Saccharum spontaneum L.）进行遗传多样性分析。结果显示：（1）5对引物共获得119个扩增片段,其中110个为多态性条带,平均多态性条带比例为92.44%,平均多态信息量为92.53%,十倍体割手密抗旱功能标记多态性最高,甘蔗常用亲本材料耐高温功能标记多态性最高。（2）十倍体割手密在抗旱功能标记上具有较低的平均相似性系数值（0.541）和最大的分布范围（0.347-0.800）,且主要集中在0.400-0.600之间,而在耐高温功能标记上甘蔗常用亲本材料虽拥有最大的分布范围（0.238-1.000）,但甘蔗原种具有最低的平均相似性系数值（0.481）,且相似性系数范围主要集中在0.400-0.600之间。（3）UPGMA聚类可将参试材料划分为较明显的两个大组,十倍体割手密与甘蔗常用亲本和甘蔗原种在聚类关系上表现出明显的不同。研究表明,十倍体割手密资源无论是在抗旱功能标记DBF、Aqua方面,还是在耐高温功能标记SCB174、SCB190方面都与甘蔗常用亲本和甘蔗原种具有较大的遗传差异,而且在抗旱功能标记方面表现出更为丰富的遗传变异,因此在后续甘蔗品种抗逆性状改良和亲本创新上应进一步加大十倍体割手密资源的利用。

Orthoploidy Saccharum spontaneum L.is an important wild parent and gene pool related stress tolerance of modern sugarcane varieties,in order to understand their genetic background of resistant genes,we screened 50 clones of decaploid S.spontaneumL.with 63 sugarcane commonly used parents and 8 original species as control in genetic diversity by using these functional markers derived from DREB,AQP,HSP70,WRKY1 and arbitrary primers,of which are related to drought and high temperature tolerance.The results showed that：（1）119 bands were gained,110 of which belong to polymorphic ones,and the mean percentage of polymorphic bands and polymorphism information content reached to 92.44% and92.53% respectively.The polymorphic level of decaploid S.spontaneumL.in the functional markers related drought tolerance was the richest;however the commonly used parents exhibited the most diversity in functional markers related high temperature tolerance.（2）In terms of Jaccard coefficient,decaploid S.spontaneumL.showed low mean value（0.541）and big distribution range（0.347-0.800）in the functional markers of drought tolerance,and most focused on the interval region of 0.400-0.600;for functional markers of high temperature tolerance,the biggest distribution range（0.238-1.000）appeared in commonly used parents,whereas the lowest value of coefficient（0.481）was found in the original materials mainly distribute with the interval region of 0.400-0.600.（3）By using UPGMA cluster method,all accessions could be divided into two big groups,one was consisted of decaploid S.spontaneumL.accessions,which exhibited evident difference from others;the other was composed by commonly used parents and original species.Overall,our results proofed that the decaploid S.spontaneumL.accessions have big genetic differences in functional markers of DBF,Aqua,SCB174 and SCB190 from commonly used parents and original species,and possess more abundant genetic variances in functional markers of drought tolerance.So in future,decaploid S.spontaneumL.resources should be utilized in improving stress tolerance of sugarcane varieties,especially in the impact of drought tolerance.