外源褪黑素和脱落酸对干旱胁迫下葡萄生理特性的影响

Effects of exogenous melatonin and abscisic acid on physiological characteristics of grape seedlings under drought stress

为了探讨褪黑素(MT)和脱落酸(ABA)两者混合施用对植物响应干旱胁迫的综合效应,以盆栽‘阳光玫瑰’葡萄为材料,通过根灌100μmol·L^-1的MT溶液和叶面喷施50μmol·L^-1的ABA溶液及二者组合处理,研究MT和ABA对干旱胁迫下葡萄生理特性的影响。结果表明,与干旱对照组(Dck)相比,MT处理导致葡萄叶片MDA、H2O2含量和相对电导率分别降低了14.42%、44.11%和21.26%,叶片相对含水量提高了1.12%,同时SOD和POD酶活性分别提高了14.00%和3.01%。这些均表明MT处理有效缓解了干旱胁迫对植株造成的损伤。50μmol·L^-1的ABA处理组叶片MDA含量和相对电导率较干旱对照组提高了9.43%和17.25%,表明ABA处理没有缓解植株的胁迫状态。MT和ABA组合处理具有和MT处理类似的效果。结果表明,褪黑素可以通过减轻膜脂过氧化程度,增强抗氧化系统能力,从而缓解干旱胁迫对葡萄的氧化损伤,提高抗旱性;同时削弱ABA带来的负面效应。

To investigate the combined effect of melatonin(MT)and abscisic acid(ABA)on plant response to drought stress,the potted seedling of‘Shine-Muscat’grape was used as material and the effects of MT and ABA on the physiological characteristics of the grape seedlings under drought stress were determined by the treatments of the root irrigation of MT solution(100μmol·L^-1),the leaf surface spray ABA solution(50μmol·L^-1),and their combination.The results indicated that MT treatment decreased the MDA,H2O2 content,and relative conductivity of grape leaves by 14.42%,44.11%,and 21.26%,respectively,comparing with the drought control group(Dck).The content of relative water content of leaves increased by 1.12%.The activities of SOD and POD enzyme were improved by 14.00%and 3.01%,respectively.The MT treatment effectively mitigated the damage to the plant caused by drought stress.However,the MDA content and the relative conductivity of leaves in the treatment of 50μmol·L^-1 ABA were 9.43%and 17.25%higher than those in the drought control group,which indicated that the stress state of the plants was not alleviated under ABA treatment.In addition,the combination of MT and ABA had a similar effect to that of MT.The results suggested that MT can reduce the degree of membrane lipid peroxide and enhance the ability of antioxidant system,so as to alleviate the oxidative damage of grape under drought stress and improve the drought resistance.At the same time,MT alleviated the negative effects of ABA.