摘要
【目的】红花玉兰根系为肉质根,对水分极为敏感,本文对红花玉兰苗木进行水淹胁迫试验,探讨水淹环境对其生长和生理生化特性的影响,为确定红花玉兰栽植适合生长的水环境及推广工作提供理论依据。【方法】以1年生红花玉兰苗木为试验材料,采用盆栽水淹方法,设置对照(CK)、水淹4 d(W4)、7 d(W7)、11 d(W11)和15 d(W15)共5个处理,并分别在水淹第1、4、7、11、15天以及胁迫解除后的第2天(R2)、5天(R5)、8天(R8)天测定红花玉兰苗木生长过程中的生长和生理生化指标,分析红花玉兰苗木对水淹胁迫的响应及其水淹胁迫后的自我恢复能力。【结果】随着水淹胁迫时间的增长:W4、W7、W11植株存活率分别降低至95.00%、70.00%、60.00%,W15苗木在解除胁迫2 d后,全部死亡;苗高和地径的增长量呈下降趋势,W11苗木胁迫解除后生长恢复基本停滞;光和色素含量呈下降趋势,W11、W15与CK差异显著;净光合速率(P_n)、蒸腾速率(T_r)和气孔导度(G_s)均呈下降趋势,P_n的各处理均显著低于CK,W11、W15的Gs与CK差异显著;蒸腾速率除W4外均与CK差异显著;可溶性蛋白含量和丙二醛(MDA)含量逐渐增加,各处理下MDA含量均与CK差异显著,可溶性蛋白含量除W4外均与CK差异显著;超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性的变化趋势大致相同,表现为先增加而后降低,W11和W15处理下的SOD和POD均与CK差异显著,CAT活性除W4外均与CK差异显著。【结论】随着水淹胁迫时间的增长,红花玉兰苗木生长和生理活性受到一定程度的抑制,但在水淹胁迫解除后具有一定的恢复能力,且胁迫时间越短恢复能力越强。水淹胁迫持续到11 d左右,基本上能够通过调节自身的保护酶系统活性和渗透调节物质含量来减轻伤害,维持植物体的正常生理代谢功能,从而表现出一定的耐涝潜力。当水淹胁迫持续至15 d时,超过了植株自身的调节能力,导致其死亡。
[Objective]Magnolia wufengensis has fleshy roots,which are very sensitive to water.In this paper,the waterlogging stress test of Magnolia wufengensis was carried out to investigate the effects of waterlogging environment on its growth,physiological and biochemical characteristics,which provided a theoretical basis for determining the suitable water environment for the growth of Magnolia wufengensis and its promotion work.[Method]One-year-old Magnolia wufengensis seedlings were used as experimental materials,and potted waterlogging method was utilized for 5 treatments:control(CK),waterlogging for 4 days(W4),7 days(W7),11 days(W11)and 15 days(W15).The growth,physiological and biochemical indexes of seedlings on days 1,4,7,11,15 after waterlogging and on the 2 nd(R2),5 th(R5),and 8 th(R8)days after stress relief were measured to analyze the response of Magnolia wufengensis seedings to waterlogging stress and self-recovery ability after waterlogging stress.[Result]With the increase of waterlogging stress time,the survival rates of W4,W7,and W11 decreased to 95.00%,70.00%,and 60.00%,respectively,and all W15 seedlings died after 2 days of stress relief;the growth of seedling height and ground diameter decreased,and the growth of W11 seedlings restored to a basic standstill after stress relief;the content of chlorophyll showed a downward trend,and the difference between W11,W15 and CK was significant;Net photosynthetic rate(P_n),transpiration rate(T_r)and stomatal conductance(G_s)showed a downward trend.Net photosynthetic rate and was significantly lower than CK in all treatments;the difference of stomatal conductance between W11,W15 and CK was significant;the transpiration rate was significantly different from CK except W4.Soluble protein content and malondialdehyde content gradually increased.The malondialdehyde content was significantly different from CK in all treatments,and soluble protein content was significantly different from CK except for W4.Superoxide dismutase(SOD),peroxidase(POD)and catalase(CAT)activities showed the same trend,which increased first and then decreased.SOD and POD under W11 and W15 treatments were significantly different from CK,and CAT activities were significantly different from CK except W4.[Conclusion]With the increase of waterlogging stress time,the growth and physiological activities of Magnolia wufengensis seedlings were inhibited to extent,but they had certain recovery ability after the relief of waterlogging stress,and the shorter the stress time was,the stronger the recovery ability was.The waterlogging stress lasts for about 11 days.And it can basically reduce the damage by regulating the activity of the protective enzyme system and the content of osmotic adjustment substance,and maintain the normal physiological and metabolic functions of the plant body.Thus,the result indicates that Magnolia wufengensis has a certain tolerance to waterlog.When the waterlogging stress lasts for 15 days,it exceeded the regulation capacity of the plant itself,which will lead to its death.
作者
王延双
方文
王欣彤
赵秀婷
廖国莉
段劼
马履一
Wang Yanshuang;Fang Wen;Wang Xintong;Zhao Xiuting;Liao Guoli;Duan Jie;Ma Lüyi(Key Laboratory for Silviculture and Conservation of Ministry of Education,Beijing Forestry University,Beijing 100083,China)
出处
《北京林业大学学报》
CAS
CSCD
北大核心
2020年第1期35-45,共11页
Journal of Beijing Forestry University
基金
林业公益行业专项(201504704)
国家自然科学基金项目(31971640)
国家林业局林业科技成果推广计划(知转2017-11),国家林业局林业标准制修订项目(2015-LY-229).
关键词
水淹胁迫
红花玉兰
生理生化
waterlogging stress
Magnolia wufengensis
physiological and biochemistry
