茶树接种AM真菌在干旱胁迫下的生理响应  

Physiological Response of Tea Plants Inoculated with Arbuscular Mycorrhizal Fungi under Drought Stress

作　　者：鲁薇 邬晓龙 胡贤春[1] 郝勇 刘春艳[1] LU Wei;WU Xiaolong;HU Xianchun;HAO Yong;LIU Chunyan(College of Horticulture and Gardening,Yangtze University,Jingzhou 434025,China;College of Urban Construction,Yangtze University,Jingzhou,434023,China)

机构地区：[1]长江大学园艺园林学院,湖北荆州434025 [2]长江大学城市建设学院,湖北荆州434023

出　　处：《茶叶科学》2024年第5期718-734,共17页Journal of Tea Science

基　　金：国家自然科学基金(32102315);茶树生物学与利用国家重点实验室开放基金(SKLTOF20200122)。

摘　　要：为探究干旱胁迫下丛枝菌根(Arbuscular mycorrhizal,AM)真菌对茶树生长及生理的作用机理,以福鼎大白茶(Camellia sinensis cv.‘Fuding Dabaicha’)茶树实生苗为试验材料,采用温室盆栽法,在正常水分和干旱胁迫下分别接种或不接种AM真菌幼套近明球囊霉(Claroideoglomus etunicatum),探究AM真菌在不同干旱胁迫时长(4周、6周、8周)下对茶树实生苗生长、光合、渗透调节及气孔开度等的生理响应。结果显示,在两种不同的水分条件下,接种AM真菌处理均显著促进了茶树生长,增加了地上部和地下部生物量,改善了根系构型,与不接种AM真菌相比,茶树根系总长度、二级侧根和三级侧根的数量、叶片渗透势分别增加了20.00%~38.77%、48.90%~163.33%、60.00%~442.86%、29.77%~41.24%,降低了干旱胁迫下茶树叶片气孔密度和相对电导率,与不接种AM真菌相比分别降低了16.00%~42.37%、2.21%~6.67%,且在干旱胁迫下的效果更为显著。干旱胁迫显著抑制了AM真菌对茶树根系的侵染和茶树的生长,表现为抑制了茶树根系构型的建立,降低了叶片叶绿素含量、最大光量子效应(QY_max)、叶片相对含水量(RWC)、气孔开度及渗透势等。接种AM真菌能显著缓解这种抑制效应,改善茶树对干旱胁迫的生理响应,从而促进茶树生长。研究表明,AM真菌可通过优化茶苗根系构型,提高茶苗叶片的保水和光合能力,调节气孔及渗透平衡,从而促进植株对水分和养分的吸收,缓解干旱对茶树的损伤,提高茶树实生苗的抗旱能力,且随着干旱时间的延长AM真菌的促进效果更为显著。To explore the mechanism of arbuscular mycorrhizal(AM)fungi on the growth and physiological characteristics of tea plants under drought stress,tea cultivar‘Fuding Dabaicha’was used as experimental material to inoculate with or without(Claroideoglomus etunicatum)under well-watered and drought stress.Plant growth performance,photosynthesis,osmotic regulation and stomatal aperture were determined to investigate the effect of AMF on tea seedlings under different duration of DS(4 weeks,6 weeks and 8 weeks).The results show that under well-watered and drought stress conditions,AMF inoculation significantly promoted plant growth performance,increased the shoot and root biomass,improved the root system architecture,in particularly increased total root length,secondary and tertiary lateral root numbers,and leaf osmotic potential by 20.00%-38.77%,48.90%-163.33%,60.00%-442.86%,29.77%-41.24%,decreased the stomatal density and relative conductance under drought stress by 16.00%-42.37%and 2.21%-6.67%respectively.The effects were more significant under drought stress.Whereas,drought stress significantly inhibited the root AMF colonization and plant growth,as evidenced by impaired establishment of root system architecture,reduced leaf chlorophyll content,maximum light quantum effect(QY_max),leaf relative water content,stomatal aperture and osmotic potential,etc.AMF inoculation could significantly alleviate this inhibitory effect,improve the physiological response of tea plants under drought stress and thus promote tea plant growth.The results indicate that AMF could promote the absorption of water and nutrients,alleviate the damage of drought stress and improve the drought resistance of tea seedlings by improving root morphology,promoting the water retention and photosynthetic capacity,adjusting the stomatal and osmotic balance,and the promotion effect of AMF became more significant with the extension of drought time.

关 键 词：茶树生长 生理特性 丛枝菌根真菌 干旱胁迫 

分 类 号：S571.1[农业科学—茶叶生产加工] S326[农业科学—作物学]