中蔗系列品种(系)苗期抗旱性综合评价及抗旱指标筛选

Comprehensive evaluation of drought resistance for sugarcane Zhongzhe varieties submitted to drought stress

干旱严重影响甘蔗的产量和品质,是制约甘蔗产业发展的主要环境胁迫之一。中蔗系列品种具备较好的综合农艺性状和育种应用潜力,但其抗旱性及具体生理响应尚缺乏系统分析。研究以中蔗系列品种(系)中蔗1号(ZZ1)、中蔗2号(ZZ2)、中蔗5号(ZZ5)、中蔗6号(ZZ6)、中蔗9号(ZZ9)、中蔗13号(ZZ13)为对象,以新台糖22(ROC22)为参照材料,对幼苗进行土壤自然干旱处理后,系统分析了生长、根系活力、叶片相对含水量、抗氧化酶活性和氧化产物、渗透调节物质、光合参数和叶绿素荧光参数等24项指标的抗旱系数;采用主成分分析法、加权隶属函数分析和聚类分析法联合分析,结果显示:ZZ9、ZZ5抗旱能力最强,ZZ6与ZZ13次之,ZZ2、ZZ1与ROC22抗旱能力相似。关联分析表明,根系活力、生长情况、叶片相对含水量、光合参数和叶绿素荧光参数等指标与甘蔗苗期抗旱性密切相关,可以作为甘蔗苗期抗旱评价的优选指标。

Drought seriously affects the yield and quality of sugarcane,which is one of the main factors restricting the development of sugarcane industry.Previous research of field trials has showed that the varieties of Zhongzhe(ZZ)are elite lines for sugarcane breeding.However,it is unclear how drought-resistant they are and what their physiological reaction is in response to drought.In this study,the six ZZ varieties,ZZ1,ZZ2,ZZ5,ZZ6,ZZ9,and ZZ13,were compared with ROC22 under drought treatment using one-month-old seedlings.A total of 24 traits were analyzed,including growth rate,root activity,leaf relative water content,the activity of antioxidant enzyme and oxidation production,osmoregulation substances,photosynthetic parameters and chlorophyll fluorescence parameters.Analyses through principal components analysis(PCA),weighted membership functions analysis,and assay of fluorescence intensity of chlorophyll demonstrated:ZZ9,ZZ5,ZZ6,and ZZ13 showed higher level of drought resistance than ROC22.ZZ2 and ZZ1 have the similar level of drought resistance with ROC22.Further correlation analysis show that root activity,growth rate,relative water content of leaves,photosynthetic efficiency and fluorescence intensity of chlorophyll showed tight relationship with drought resistance,and those can be used as the representative indicators for drought resistance evaluation for sugarcane seedlings.