香根草根系分泌物对重金属胁迫下两种草坪草种子萌发的影响  

Effects of vetiver grass root exudates on the germination of two turfgrass species under heavy metal stress

作　　者：牛学礼 丘雯鑫 杨锦玉 刘金祥 章武 NIU Xueli;QIU Wenxin;YANG Jinyu;LIU Jinxiang;ZHANG Wu(Lingnan Normal University,Zhanjiang 524048,Guangdong,China)

机构地区：[1]岭南师范学院,广东湛江524048

出　　处：《草业科学》2020年第6期1074-1087,共14页Pratacultural Science

基　　金：岭南师范学院科研处19年校级人才专项(1170919629);广东省自然科学基金项目(2020A1515010238);广东省科技创新战略专项资金项目(2018A03013)。

摘　　要：为探究香根草(Vetiveria zizanioides)根系分泌物对高羊茅(Festuca arundinacea)和多年生黑麦草(Lolium perenne)在重金属胁迫条件下种子萌发的缓解效应,采用室内水分发芽床试验,研究了香根草根系分泌物水浸液对单一的不同浓度重金属(锌、铜、镉)胁迫下两种草坪草的种子萌发和幼苗生长的影响。结果表明:与对照相比,香根草根系分泌物水浸液显著(P<0.05)提高了200 mg·L^-1的Cu^2+胁迫下两种草坪草种子的发芽率以及200 mg·L^-1的Cd^2+胁迫下高羊茅的发芽率。与蒸馏水相比,香根草根系分泌物显著(P<0.05)增加了多年生黑麦草在200、400、600 mg·L^-1Zn^2+,100、200 mg·L^-1 Cu^2+以及200 mg·L^-1 Cd^2+胁迫下的苗长;50 mg·L^-1 Cu^2+以及50、100、200 mg·L^-1 Cd^2+胁迫下的根长。香根草根系分泌物显著(P<0.05)增加了高羊茅在50、200 mg·L^-1 Cu^2+和50、100、200 mg·L^-1 Cd^2+胁迫下的苗长,以及50、100 mg·L^-1 Cu^2+和200 mg·L^-1 Cd^2+胁迫下的根长、最长根和根数。本研究为香根草根系分泌物提高高羊茅和多年生黑麦草种子在Cu和Cd胁迫下的萌发特性提供科学依据,也为香根草更广泛的利用方式提供基础资料。The aim of the present study was to explore the effect of vetiver grass(Vetiveria zizanioides)root exudates(RE)on alleviating the effects of heavy metal toxicity on the germination of tall fescue(Festuca arundinacea)and perennial ryegrass(Lolium perenne).Moisture germination bed text was employed to study the effects of vetiver grass RE on the germination and seedling growth of two turfgrass species under the single stresses of zinc(Zn),copper(Cu),and cadmium(Cd)at different concentrations.The results showed that vetiver grass RE significantly(P<0.05)improved the seed germination percentages(SGP)of the two turfgrass species under Cu^2+stress at 200 mg·L^-1 and improved the SGP of tall fescue under Cd^2+stress at 200 mg·L^-1 compared to the control treatment.Compared to distilled water,vetiver grass RE significantly(P<0.05)increased the shoot length(SL)of perennial ryegrass under Zn^2+treatments at 200,400,and 600 mg·L^-1,Cu^2+treatments at 100 and 200 mg·L^-1,and Cd^2+treatment at 200 mg·L^-1.Vetiver grass RE also increased perennial ryegrass root length(RL)under Cu^2+treatment at 50 mg·L^-1 and Cd^2+treatments at 50,100,and 200 mg·L^-1.In addition,vetiver grass RE significantly(P<0.05)increased the SL of tall fescue under Cu^2+treatments at 50 and 200 mg·L^-1 and Cd^2+treatments at 50,100,and 200 mg·L^-1,and increased the RL,with the longest roots and greatest root numbers under Cu^2+treatments at 50 and 100 mg·L^-1 and Cd^2+treatment at 200 mg·L^-1.This experiment provides a scientific basis for improving the germination characteristics of tall fescue and perennial ryegrass using vetiver grass RE under Cu^2+and Cd^2+stresses,and provides basic information for the wider utilization of vetiver grass.

关 键 词：香根草 根系分泌物 重金属胁迫 高羊茅 多年生黑麦草 种子萌发 

分 类 号：S688.4[农业科学—观赏园艺]