叶面喷施亚精胺对干旱胁迫下闽楠幼苗生理的影响

Effects of Spermidine on Physiology of Phoebe bournei Seedlings Under Drought Stress

为了解决闽楠苗木繁育中常因水分亏缺导致生长不良及死亡的问题,以1年生闽楠幼苗为材料,研究干旱胁迫下施加不同浓度外源亚精胺对闽楠幼苗光合生理的影响,探究亚精胺对闽楠幼苗干旱胁迫的缓解作用。结果表明:外源亚精胺处理可在一定程度上提高P_(n)、Gs及抗氧化酶活性,降低Pro和MDA含量,缓解干旱胁迫对闽楠的影响;其中0.1 mmol/L浓度的亚精胺效果最好,其处理后P_(n)和WUE明显高于其他处理,尤其到干旱胁迫后期效果显著,胁迫第32天P_(n)和WUE分别比CK高82.1%、123.7%,差异显著;抗氧化酶SOD、CAT分别比CK高41.1%和35.1%,差异显著;Pro、MDA分别比CK低21.6%、22.6%,差异显著。

In order to solve the problem of poor growth and even death caused by water shortage in the breeding of Phoebe bournei seedlings,this study used the 1-year-old P.bournei seedlings with different concentrations of exogenous spermidine to study the mitigation effect of spermidine on the drought stress of P.bournei seedlings.The results showed that treatment with exogenous spermidine can increased the net photosynthetic rate(P_(n)),stomatal conductance(Gs)and the activities of antioxidant enzymes(SOD,POD,CAT)of P.bournei to some extent,reduced the contents of proline(Pro)and malondialdehyde(MDA),and alleviated the influence of drought stress on P.bournei.Among them,spermidine at a concentration of 0.1 mmol/L had the best effect.After treatment,P_(n) and WUE were significantly higher than those of other treatment groups,especially in the late stage of drought stress.P_(n) and WUE were 82.1%,123.7%higher than the control on the 32nd day of stress,the antioxidant enzymes SOD and CAT were 41.1%and 35.1%higher than the control,and Pro and MDA were 21.6%and 22.6%lower than the control,respectively.