干旱胁迫及复水对槟榔幼苗形态和生理特性的影响  

Effects of drought stress and rehydration on the morphology and physiological characteristics of betel nut seedlings

作　　者：戚金存 刘大泉 刘泓 金鑫 陈明婉 吕猛 杨福孙 李昌珍 QI Jin-cun;LIU Da-quan;LIU Hong;JIN Xin;CHEN Ming-wan;LYU Meng;YANG Fu-sun;LI Chang-zhen(College of Tropical Agriculture and Forestry,Hainan University,Haikou 570228,China)

机构地区：[1]海南大学热带农林学院,海南海口570228

出　　处：《江苏农业学报》2024年第4期615-624,共10页Jiangsu Journal of Agricultural Sciences

基　　金：海南省棕榈类(槟榔)现代农业产业技术体系项目(HNARS-1-G3)。

摘　　要：本研究采用盆栽控水法,对槟榔幼苗在干旱胁迫和复水过程中发生的形态和生理特性变化进行研究,以评价干旱胁迫和复水对槟榔幼苗的影响。以正常浇水为对照(CK),设置干旱时间分别为5 d、10 d、15 d、20 d、25 d、30 d,在每个干旱时间节点取样后立即进行复水,并在复水后1 d、4 d、7 d分别取样。研究结果表明:干旱后,槟榔幼苗根冠比增加;复水后,根冠比除干旱5 d恢复到CK水平外,其余处理均未恢复到CK水平。根、茎、叶和种核含水量以及净光合速率(A)、蒸腾速率(E)、胞间CO_(2)浓度(Ci)、气孔导度(Gs)均随着干旱时间的延长呈现递减趋势;在干旱胁迫30 d时根、茎、叶和种核含水量以及A、E、Ci和Gs达到最低,与CK相比分别下降了21.87%、28.97%、75.01%、34.24%、100.00%、92.64%、75.05%和95.70%;复水后,根、茎、叶和种核含水量以及A、E、Ci和Gs均在干旱20 d前复水后恢复效果明显,但在干旱25 d复水后效果不明显。过氧化物酶(POD)活性呈现先升后降再升高趋势,过氧化氢酶(CAT)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量则随着干旱时间的延长呈现先升后降趋势;SOD活性在干旱10 d时达到最大值,与CK相比增加了9.48%;CAT和POD活性则在干旱15 d达到最大值,与CK相比分别增加317.99%和44.88%;MDA在干旱25 d时达到最高,与CK相比增加了59.99%。综上所述,槟榔幼苗能维持正常生长的最长干旱时间是20 d,当持续干旱超过20 d后,将对槟榔幼苗造成无法逆转的伤害,故在持续干旱20 d内必须对槟榔幼苗进行灌溉。In this study,changes in morphological and physiological characteristics of betel nut seedlings during drought stress and rehydration were investigated by using potting water control method to evaluate the effects of drought stress and rehydration on betel nut seedlings.Normal watering was used as the control(CK)and the drought time was set to 5 d,10 d,15 d,20 d,25 d,and 30 d.Rewatering was performed immediately after sampling at each drought time node,and sampling was performed on 1 d,4 d,and 7 d after rewatering,respectively.The results showed that the root-crown ratio of betel nut seedlings increased after drought.After rewatering,the root-crown ratio did not return to the CK level except for the 5 d drought treatment.The water content of roots,stems,leaves and seed kernels,net photosynthetic rate(A),transpiration rate(E),intercellular CO2 concentration(Ci)and stomatal conductance(Gs)showed decreasing trends with the extension of drought time.The water content of roots,stems,leaves and seed kernels,as well as A,E,Ci and Gs reached the minimum at 30 d of drought stress,decreasing by 21.87%,28.97%,75.01%,34.24%,100.00%,92.64%,75.05%and 95.70%,respectively,compared with CK.The water content of roots,stems,leaves and seed kernels,and A,E,Ci and Gs all recovered significantly after rewatering before 20 days of drought,but the recovery effect was not obvious at 25 days of drought.Peroxidase(POD)activity showed a trend of increasing first,then decreasing and then increasing,while catalase(CAT)activity,superoxide dismutase(SOD)activity and malondialdehyde(MDA)content increased first and then decreased with the extension of drought time.The activity of SOD reached the maximum at 10 d of drought,increasing by 9.48%compared with that in CK.The activities of CAT and POD reached the maximun at 15 d of drought,increasing by 317.99%and 44.88%,respectively,compared with CK.The content of MDA reached the highest at 25 d of drought,which increased by 59.99%compared with CK.In summary,the longest drought time for betel nut seedl

关 键 词：槟榔幼苗 干旱胁迫 复水 形态指标 生理特性 

分 类 号：S792.91[农业科学—林木遗传育种]