摘要
[目的]探明外源槲皮素(Quercetin,Q)提高板栗苗耐旱性的适宜喷施浓度及其生理机制.[方法]以燕宝(YB)板栗苗为试材,通过盆栽控水的方法,以重度干旱胁迫CK1和正常管理CK2为对照,研究在重度干旱胁迫下喷施不同浓度[600μmol·L-1(QD1)、1200μmol·L-1(QD2)、1800μmol·L-1(QD3)和 2000 μmol·L-1(QD4)、3000μmol·L-1(QD5)]槲皮素对板栗幼苗叶绿素含量、抗氧化酶活性、丙二醛(MDA)和黄酮醇含量的影响.[结果]与同处于重度干旱胁迫下未经槲皮素喷施处理的CK1相比,5种不同浓度槲皮素喷施处理均能显著提高板栗叶片叶绿素含量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性和黄酮醇含量,同时显著降低了板栗叶片丙二醛(MDA)含量,但喷施后板栗苗的状态仍不能恢复到正常管理的CK2.通过主成分分析及隶属函数法,得出QD1、QD2、QD3、QD4、QD5各处理的平均抗旱性度量值分别为0.735、0.641、0.738、1.389、0.828.其中2000μmol·L-1(QD4)槲皮素浓度处理效果更显著.[结论]外源施加槲皮素可以通过提高板栗幼苗抗氧化酶活性、叶绿素含量,减缓MDA增加速度,减缓细胞膜质过氧化的速度,以减轻干旱对板栗叶片细胞的伤害,从而提高板栗幼苗耐旱性,且以2000μmol·L-1(QD4)槲皮素浓度处理效果最好.
Abstract
[Objective]Physiological mechanism and application concentration of foliar quercetin(Q)spray in improving drought resistance of chestnut seedlings were studied.[Method]In an irrigation-controlled pot experiment,seedlings of Yanbao chestnut(YB)were sprayed Q solutions of concentrations at 600 μmol·L-1(QD1),1 200 μmol L-1(QD2),1 800μmol·L-1(QD3),2 000 μmol·L-1(QD4),and 3 000 μmol·L-1(QD5),along with one non-spray control under drought(CK1)and another under normal watering condition(CK2).Contents of chlorophyll,malondialdehyde(MDA),and flavonols as well as antioxidant activities of the seedlings were determined.[Result]The foliar spray of Q significantly elevated the contents of chlorophyll and flavonols as well as the activities of superoxide dismutase(SOD),catalase(CAT),and peroxidase(POD)and reduced MDA in the seedling leaves over those under CK1,but not to the levels under CK2.The principal component and membership function analyses showed the average drought resistance of QD1,QD2,QD3,QD4,and QD5 to be 0.735,0.641,0.738,1.389,and 0.828,respectively,indicating a superior treatment effect of 2,000μmol Q·L-1.[Conclusion]Spraying Q solutions on the chestnut seedlings appeared to mitigate cellular damages induced by drought stress.The treatment raised the antioxidant enzyme activities and chlorophyll content while reduced MDA that retarded cell membrane peroxidation on the leaves with the greatest effect displayed by the application of Q at a concentration of 2 000 μmol·L-1.
基金项目
国家重点研发计划项目(2022YFD2200400)
教育部工程研究中心项目(PT2022-01)
维普
万方数据