外源钙对干旱胁迫下喜树幼苗缓解效应  

Alleviating Effect of Exogenous Calcium on Camptotheca acuminata Seedlings under Drought Stress

作　　者：廖向研 谭鹰 邬桥平 刘志贤 LIAO Xiangyan;TAN Ying;WU Qiaoping;LIU Zhixian(Huaiji County Henan Nursery Farm,Huaiji 526400,Guangdong;Huaiji Sanyue Provincial Nature Reserve Management Office,Huaiji 526400,Guangdong;Huaiji County Forestry Technology Extension Center,Huaiji 526400,Guangdong;College of Forestry,Guangxi University,Nanning 530004,Guangxi)

机构地区：[1]怀集县河南苗圃场,广东怀集526400 [2]广东省怀集三岳省级自然保护区管理处,广东怀集526400 [3]怀集县林业技术推广中心,广东怀集526400 [4]广西大学林学院,广西南宁530004

出　　处：《温带林业研究》2023年第4期21-26,共6页Journal of Temperate Forestry Research

基　　金：广西林业科研与推广项目(g19kt112)。

摘　　要：【目的】钙参与植物体内多种生理代谢过程,调控着植物的生长发育。喜树抗旱能力差,研究旨在探究外源钙在提升喜树抗旱性方面的潜力。【方法】本试验以喜树幼苗为试验材料,通过PEG 4000模拟干旱胁迫的方法,分析了不同浓度Ca Cl_(2)对PEG处理下幼苗生长生理的影响。【结果】与对照(0%PEG)相比,10%PEG导致幼苗遭受了明显的胁迫伤害,存活率、生物量降低,叶片相对水分亏缺(RWD)增加,净光合速率(Pn)、水分利用效率(WUE)、胞间CO_(2)浓度(Ci)、叶绿素含量下降,蒸腾速率(Tr)、气孔导度(Gs)、丙二醛(MDA)含量增大,SOD、POD活性减小。在2~6 mg·L^(-1)Ca Cl_(2)作用下,对照处理幼苗表现出低促高抑的效果,在Ca Cl_(2)浓度为6 mg·L^(-1)时,幼苗生长生理受到了明显的抑制,而10%PEG处理幼苗生长生理均得了明显的改善。以幼苗存活率、生物量增量、叶片RWD、Pn、Tr、WUE、Gs、Ci、叶绿素含量、SOD活性、POD活性、CAT活性、MDA含量为评价指标,通过主成分分析进行综合评价,10%PEG+0~6 mg·L^(-1)Ca Cl_(2)4个处理下幼苗生长生理表现排名为:10%PEG+4 mg·L^(-1)Ca Cl_(2)>10%PEG+6 mg·L^(-1)Ca Cl_(2)>10%PEG+2 mg·L^(-1)Ca Cl_(2)>10%PEG+0 mg·L^(-1)Ca Cl_(2)。【结论】研究结果显示外源Ca Cl_(2)能明显提升喜树幼苗抗旱性,在10%PEG 4000处理下,以4 mg·L^(-1)Ca Cl_(2)使用效果最佳。【Objective】Calcium is involved in a variety of physiological metabolic processes in plants and regulates the growth and development of plants.Camptotheca acuminata has poor drought resistance.This study aimed to explore the potential of exogenous calcium in improving the drought resistance of Camptotheca acuminata.【Method】The effects of different concentrations of CaCl_(2)on the growth and physiology of seedlings under PEG treatment were analyzed by PEG 4000 simulated drought stress.【Result】The results showed that compared with the control(0%PEG),10%PEG caused obvious stress damage to seedlings,decreased survival rate and biomass,increased relative water deficit(RWD)of leaves,decreased net photosynthetic rate(Pn),water use efficiency(WUE),intercellular carbon dioxide concentration(Ci)and chlorophyll content,increased transpiration rate(Tr),stomatal conductance(Gs)and malondialdehyde(MDA)content,and decreased SOD and POD activities.Under the action of 2-6 mg·L^(-1)CaCl_(2),the seedlings of the control treatment showed the effect of low promotion and high inhibition.When the concentration of CaCl_(2)was 6 mg·L^(-1),the growth physiology of the seedlings was significantly inhibited,while the growth physiology of the seedlings treated with 10%PEG was significantly improved.The seedling survival rate,biomass increment,leaf RWD,Pn,Tr,WUE,Gs,Ci,chlorophyll content,SOD activity,POD activity,CAT activity and MDA content were used as evaluation indexes,and comprehensive evaluation was carried out by principal component analysis.The physiological performance of seedling growth under 4 treatments of 10%PEG+0-6 mg·L^(-1)CaCl_(2)was ranked as follows:10%PEG+4 mg·L^(-1)CaCl_(2)>10%PEG+6 mg·L^(-1)CaCl_(2)>10%PEG+2 mg·L^(-1)CaCl_(2)>10%PEG+0 mg·L^(-1)CaCl_(2).【Conclusion】The results indicated that exogenous CaCl_(2)could significantly improve the drought resistance of Camptotheca acuminata seedlings.Under the treatment of 10%PEG 4000,the effect of 4 mg·L^(-1)CaCl_(2)was the best.

关 键 词：喜树 干旱胁迫 钙信号 抗性育种 

分 类 号：S792.99[农业科学—林木遗传育种]