外源多效唑对干旱胁迫下闽楠幼苗抗旱性的影响  

Effect of exogenous paclobutrazol on the drought resistance of Phoebe bournei seedlings under drought stress

作　　者：宋艳艳 徐培月 何功秀[1,2] 胡孔飞 及利 杨丽丽[2] 孙洪刚[4] 张勰[5] SONG Yanyan;XU Peiyue;HE Gongxiu;HU Kongfei;JI Li;YANG Lli;SUN Honggang;ZHANG Xie(College of Forestry,Central South University of Forestry and Technology,Changsha 410004,China;National Engineering Laboratory of Southern Forestry Ecological Application Technology,Changsha 410004,China;Hunan Jinghui Agriculture and Forestry Ecological Technology Co.Lud.,Changsha 410004,China;Research Instiute of Subtropical Foresry,Chinese Academy of Forestry,Hangzhou 310000,China;Hunan Academy of Forestry,Changsha 410004,China)

机构地区：[1]中南林业科技大学林学院,长沙410004 [2]南方林业生态应用技术国家工程实验室,长沙410004 [3]湖南景辉农林生态科技有限公司,长沙410004 [4]中国林业科学研究院亚热带林业研究所,杭州310000 [5]湖南省林业科学院,长沙410004

出　　处：《应用生态学报》2024年第10期2667-2676,共10页Chinese Journal of Applied Ecology

基　　金：杉木闽楠混交林培育技术研究与示范项目(2021YFD2201303);长沙市雨花区科技计划项目(YHKJ-2022-ZN-02)资助。

摘　　要：为明确外源多效唑对闽楠幼苗抗旱性的响应机制,以2年生闽楠幼苗为试材,采用自然干旱法,研究不同浓度多效唑(25、50、100mg·L^(-1))喷施对干旱胁迫下闽楠幼苗光合系统和抗氧化系统的影响。结果表明:干旱胁迫显著减弱闽楠幼苗的光合作用,打破抗氧化系统的动态平衡,不同浓度多效唑喷施均能有效缓解干旱胁迫下闽楠幼苗受到的胁迫损伤,提升光合系统和抗氧化系统的防御能力,其中100mg·L^(-1)多效唑处理最为有效。100mg·L^(-1)多效唑处理下,与干旱处理相比,闽楠幼苗叶片中叶绿素总量显著增加,最高增幅为51.9%,表观光合电子传递速率、光化学淬灭系数、实际光化学量子产量显著提高,最高增幅分别为67.8%、58.4%、59.7%,净光合速率、气孔导度、蒸腾速率显著增长,最高增幅分别为65.5%、65.4%、68.6%。外源100mg·L^(-1)多效唑通过调控闽楠幼苗光合系统和抗氧化系统提升闽楠幼苗抗旱性的能力最强。To clarify the response mechanism of exogenous paclobutrazol on drought resistance in Phoebe bournei seedlings,we investigated the effects of spraying different concentrations of paclobutrazol(25,50,100 mg·L^(-1))on the photosynthetic and antioxidant systems of 2-year-old P.bournei seedlings under drought stress using natural drought method.The results showed that drought stress significantly reduced the photosynthesis and broke the dynamic balance of antioxidant system in P.bournei seedlings.Spraying with dfferent concentrations of paclobutrazol effectively alleviated the negative impacts of drought stress,and enhanced the defense capability of photosynthetic and antioxidant systems,with the 100 mg·L^(-1) paclobutrazol treatment being the most effective.Under exogenous 100 mg·L^(-1) paclobutrazol treatment,the total chlorophyll in leaves increased significantly,with a maximum increase of 51.9%.The apparent photosynthetic electron transfer rate,photochemical quenching coefficient and actual photochemical quantum yield were significantly increased,with maximum increase of 67.8%,58.4%,and 59.7%,respectively.The net photosynthetic rate,stomatal conductance and transpiration rate,were enhanced,reaching maximum increase of 65.5%,65.4%,and 68.6%,respectively.In summary,exogenous 100 mg·L^(-1) paclobutrazol has the strongest ability to enhance drought resistance of P.bournei seedlings by regulating photosynthetic and antioxidant systems.

关 键 词：闽楠 多效唑 干旱胁迫 抗旱性 

分 类 号：S792.24[农业科学—林木遗传育种]