30份割手密种质资源苗期抗旱性综合评价

Comprehensive evaluation on drought resistance of thirty Saccharum spontaneum L.accessions in seedling stage

【目的】依据生理生化指标综合评价不同基因型割手密种质资源的苗期抗旱性,为甘蔗抗旱性育种的亲本选育提供参考。【方法】以30份割手密野生种质为试验材料进行盆栽试验,测定割手密苗期干旱胁迫处理前后的6项生理生化指标,采用主成分分析、模糊隶属函数分析和聚类分析对割手密的抗旱性进行综合评价。【结果】与正常供水相比,干旱胁迫下各割手密种质材料的过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、过氧化物酶(POD)活性增强,丙二醛(MDA)、可溶性糖(SS)、脯氨酸(Pro)含量增加,但各指标的变化程度因材料不同而存在一定差异。相关性分析结果表明,在干旱胁迫下,不同割手密种质材料叶片的过氧化氢酶活性和脯氨酸含量之间呈显著正相关(P<0.05),超氧化物歧化酶活性和脯氨酸之间呈极显著正相关(P<0.01);过氧化物酶活性和超氧化物歧化酶活性之间呈显著负相关;过氧化氢酶活性与丙二醛含量之间也呈显著负相关,其他指标之间无显著相关性(P>0.05)。主成分分析表明,SOD活性、POD活性、CAT活性和Pro含量、SS含量、MDA含量可作为割手密抗旱性评价的重要指标。通过模糊隶属函数分析和聚类分析可将30份割手密种质材料划分为4类,其中高度抗旱材料1份(90⁃53),中高度抗旱材料2份,中度抗旱材料14份,低度抗旱材料13份。【结论】CAT活性、SOD活性、POD活性、MDA含量、SS含量、Pro含量可作为割手密苗期的抗旱性评价指标。30份参试割手密种质中,90⁃53的抗旱性最强,2015⁃22、88⁃301次之,2015⁃104的抗旱性最弱。

【Objective】In order to provide reference for parent selection of drought resistance breeding in sugarcane,physiological and bio⁃chemical indices were used to evaluate the drought resistance of different genotypes of Saccharum spontaneum in seedling stage.【Method】Thirty S.spontaneum accessions were used as the materials under the normal water and drought stress treatment,and six physiological and biochemical indices were determined at the seedling stage.Comprehensive evaluation of drought resistance was implemented by the methods of principal component analysis,fuzzy membership function analysis and cluster analysis.【Result】Compared with the normal water suppy,the activities of CAT,SOD,POD and the contents of MDA,SS and Pro increased under drought stress,but the changes of each index were diferent due to diftrent materials.The results of correlation analysis showed that under drought stress,CAT activity of leaves was significantly positively correlated with Pro content(P<0.05);SOD activity of leaves was extremely positively correlated with Pro content(P<0.01);There was a significant negative correlation between POD activity and SOD activity;There was also a significant negative correlation between catalase activity and MDA content,while there was no significant correlation between other indicators(P>0.05).The principal component analysis showed that the activities of SOD,POD,CAT and the contents of Pro,SS,MDA could be used as important indicators for drought re⁃sistance evaluation.Fuzzy membership function analysis and cluster analysis showed that the 30 accessions could be divided into 4 catego⁃ries,including 1 accession as the high drought⁃resistant type(90⁃53),2 accessions as the medium high drought⁃resistant type,14 accessions as the drought⁃resistant type and 13 accessions as the drought⁃sensitive type.【Conclusion】The activities of CAT,SOD,POD and the con⁃tents of MDA,SS and Pro could be used as the drought resistance evaluation index of S.spontaneum at the seedling stage.Among the 30 accessions tested,the 90⁃53 had the strongest drought resistance,followed by 2015⁃22 and 88⁃301,2015⁃104 had the weakest drought resist⁃ance.