聚乙二醇模拟干旱胁迫对细叶云南松种子萌发及生理的影响  

Effects of PEG Simulated Drought Stress on Seed Germination and Physiology of Pinus yunnanensis

作　　者：韦秋思 徐圆圆[2] 郑党斌 赵毅辉[2] 杨梅[2] 

机构地区：[1]广西雅长林场,广西百色533209 [2]广西大学林学院,广西南宁530004

出　　处：《贵州农业科学》2016年第2期43-47,共5页Guizhou Agricultural Sciences

基　　金：广西林业厅科技项目"细叶云南松幼林栽培技术及林木综合利用研究"

摘　　要：为探明细叶云南松种子萌发期对干旱胁迫的耐受性,采用不同浓度的PEG-6000溶液(0%,0.5%,1.0%,1.5%,2.0%,2.5%,3.0%,3.5%,4.0%)模拟干旱条件研究其种子萌发、保护酶活性的变化。结果表明:1)随着干旱胁迫程度的加剧,细叶云南松种子的发芽率、发芽势和发芽指数总体呈先升高后下降趋势,在前15d,0.5%PEG浓度下发芽率最高,为29.50%,说明低浓度(0.5%)PEG胁迫可以在一定程度上促进细叶云南松种子萌发。2)随着PEG浓度的升高,细叶云南松种子中MDA含量呈低—高—低的变化,PEG浓度为1.0%和2.5%时MDA含量分别为最低和最高,为对照的0.90倍和1.85倍;SOD活性先升高再降低,1.0%PEG胁迫下SOD活性达最高,为222.30U/g FW,4.0%PEG胁迫下最低,为对照的0.50倍;CAT活性逐渐降低,4.0%PEG胁迫下其活性最低,为对照的49.34%。结论:轻度干旱(0.5%PEG浓度)对细叶云南松种子萌发有一定的促进作用,但细叶云南松种子的抗旱能力不强。The seed germination and protective enzyme activity of P.yunnanensis seeds were determined under different PEG concentration（0%,0.5%,1.0%,1.5%,2.0%,2.5%,3.0%,3.5% and4.0%）to study the drought tolerance of P.yunnanensis at seed germination stage.Results：1）The germination rate,germination potential and germination index of P.yunnanensis seeds present the first rising and then declining trend overall with increase of drought stress.The germination rate of P.yunnanensis seeds under 0.5% PEG is 29.50%（maximum）prior to 15 d,which indicates that 0.5% PEG stress can promote germination of P.yunnanensis seeds to a certain extent.2）The DNA content in P.yunnanensis seeds shows the low-high-low trend with increase of PEG concentration.The MDA content of P.yunnanensis seeds under 1.0% and 2.5% PEG is 0.90 time and 1.85 times that of CK respectively.The SOD activity of P.yunnanensis seeds shows a first rising and then declining trend with increase of PEG concentration and the SOD activity of P.yunnanensis seeds under 1.0% PEG is the maximum（222.30U/gFW）but the SOD activity of P.yunnanensis seeds under 4.0% PEG is 0.50 time that of CK.The CAT activity of P.yunnanensis seeds reduces gradually with increase of PEG concentration and the SOD activity of P.yunnanensis seeds under 4.0% PEG is the minimum,50.66% lower than CK.In conclusion,Mild drought（0.5% PEG concentration）has a certain promotion effect on germination of P.yunnanensis seeds but the drought resistance of P.yunnanensis seeds is not strong.

关 键 词：细叶云南松 种子萌发 聚乙二醇 干旱胁迫 

分 类 号：S791.257[农业科学—林木遗传育种]