9种莎草科植物种子萌发期抗旱性评价

Evaluation of drought resistance of nine Cyperaceae species seeds during germination

为了解不同抗旱性莎草科(Cyperaceae)植物在生产应用中的生态价值及适应性差异,本研究测定不同浓度聚乙二醇(PEG-6000)溶液对9种莎草科植物种子相对萌发率、相对萌发速率、相对萌发指数、相对胚芽长和相对胚根长5个指标的影响,并采用隶属函数法进行抗旱性综合评价。结果表明:随干旱胁迫强度的增加,9种莎草科植物种子萌发期各指标均呈降低趋势,种质间差异较大。其中,PEG浓度≤10%时,羽状穗砖子苗(Mariscus javanicus)、毛轴莎草(Cyperus pilosus)、高秆莎草(Cyperus exaltatus)和两歧飘拂草(Fimbristylis dichotoma)的种子萌发率与对照差异不显著(P>0.05);低浓度(5%PEG浓度)的干旱胁迫能促进羽状穗砖子苗、毛轴莎草和两歧飘拂草胚根的生长。隶属函数综合评价显示,9种莎草科植物种子萌发期抗旱性表现为毛轴莎草>碎米莎草(Cyperus iria)>高秆莎草>蕨状薹草(Carex filicina)>羽状穗砖子苗>风车草(Cyperus alternifolius)>球穗扁莎(Pycreus flavidus)>两歧飘拂草>十字薹草(Carex cruciata)。

To understand the ecological value and adaptability of different drought-resistant Cyperaceae species in terms of production and application,the relative germination rate,relative germination speed,relative germination index,relative plumule length,and relative radical length of nine Cyperaceae species were measured under simulated drought stress induced by different concentrations of PEG-6000 solution.Membership function analysis was used to evaluate drought resistance.The results showed that all seed germination indexes of the nine Cyperaceae species decreased as drought stress intensity increased,and there was a significant difference among the germplasms.When the concentration of PEG was≤10%,the seed germination rates of Mariscus javanicus,Cyperus pilosus,Cyperus exaltatus,and Fimbristylis dichotoma were similar to that of the control.Drought stress with a low concentration of PEG solution(5%)promoted seed germination of germplasms such as M.javanicus,C.pilosus,and F.dichotoma.Based on the MFA of the drought resistance of the nine Cyperaceae species,the order of drought resistance was C.pilosus>Cyperus iria>C.exaltatus>Carex filicina>M.javanicus>Cyperus alternifolius>Pycreus flavidus>F.dichotoma>Carex cruciata.