基于单条斑茅染色体无性系的甘蔗抗旱机理研究

Development of drought-resistant germplasm and mechanism research of drought-resistant is the key work of plant resistant breeding. Erianthus arundinaceus, which is one of the close relative genus to Saccharum and contain benefit resistant genes, had been used in the sugarcane breeding program for long time. Previous researches on the breeding history and the analysis of the drought tolerance of Erianthus arundinaceus showed that the benefit trait can be introduced into sugarcane genetic background and separated in the offspring of high generations. Based on the results, this study is intended to further perform the backcross between the BC4 progeny of Erianthus arundinaceus and sugarcane with the objective is creating and selecting the clone which has only one Erianthus arundinaceus chromosomes and a high level of drought resistance. The comparative transcriptome was used to analyze the changes of gene expression of the clone and ROC22 before and after drought stress. The differential expressed genes were screened and identified to reveal the metabolic pathways and regulatory networks in response to drought stress. Then identifying the genes that specifically expressed in the progeny of Erianthus arundinaceus, analyzing the expression characteristics of these genes in different clones，clarifying the relationship between their expression and drought resistance and clarifying the molecular mechanisms of drought resistance in sugarcane. This work will provide new strong drought-resistant germplasm for sugarcane breeding and also provide a new perspective for resolving the molecular mechanism of sugarcane drought resistance. Moreover, the results will allow us to gain the theoretical support for genetic improvement of sugarcane.

抗旱种质资源的开发和抗旱机理研究是抗旱育种的重点工作。斑茅是具有优良抗性基因并得到杂交利用的甘蔗近缘属植物之一。基于多年斑茅杂交利用和抗性分析发现，斑茅的优良抗旱性可以导入到甘蔗遗传背景中，且在高代回交群体中发生分离。在此基础上，本研究拟利用甘蔗与高代斑茅后代BC4进行杂交，结合GISH分析和抗性鉴定，创制、筛选仅含单条斑茅染色体且抗旱性好的无性系材料；利用比较转录组分析该无性系与ROC22在干旱胁迫前后的基因表达变化情况，筛选、鉴定二者响应干旱胁迫的差异表达基因，构建基因调控和代谢网络；鉴定在斑茅后代中特异表达的响应干旱胁迫的基因，分析其在不同抗性材料中的表达特征，明确其表达与抗旱性的关系，阐明甘蔗抗旱分子机制及斑茅染色体的导入对抗旱机制的影响。本研究可以为甘蔗育种提供新的抗旱性种质资源，为抗旱分子机理解析提供新的视角；同时也为斑茅有利基因挖掘和利用奠定基础，为甘蔗抗性分子改良提供理论。

斑茅是具有优良抗性基因并得到杂交利用的甘蔗近缘属植物之一。基于多年斑茅杂交利用和抗性分析发现，斑茅的优良抗旱性可以导入到甘蔗遗传背景中。本研究利用甘蔗与高代斑茅后代BC4进行杂交，结合GISH分析和抗性鉴定，创制了一批含不同条数斑茅染色体无性系材料；利用比较转录组分析了斑茅后代材料在干旱胁迫前后根和叶的基因表达变化情况，筛选、鉴定二者响应干旱胁迫的差异表达基因，构建了基因表达调控网络；为甘蔗抗旱分子机制及斑茅染色体的导入对抗旱的影响提供的依据。研究成果为甘蔗育种提供新的抗旱性种质资源，为抗旱分子机理解析提供新的视角；同时也为斑茅有利基因挖掘和利用奠定基础，为甘蔗抗性分子改良提供理论。