摘要
[目的]研究水杨酸(SA)对盐胁迫下莴笋的缓解效应,为盐碱地莴笋种植提供理论技术依据.[方法]以无NaCl胁迫且不喷施SA为对照1(CK1),以200 mmol/L NaCl胁迫不喷施SA为对照2(CK2);设置叶面喷施0.1、0.3、0.6、1.2、2.4 mmol/L 5个SA处理,动态测定莴笋的生长生理相关指标.[结果]与CK1处理相比,CK2处理抑制莴笋幼苗生长,降低生物量积累,增加可溶性蛋白,可溶性糖和脯氨酸含量.与CK2处理相比,叶面喷施适宜浓度水杨酸(0.6 mmol/L)可以缓解盐胁迫对莴笋生物量积累的抑制,促进莴笋叶片的可溶性蛋白、可溶性糖和脯氨酸含量的积累,增强光合作用;在胁迫第6天时,可溶性糖、可溶性蛋白、净光合速率Pn、气孔导度Gs和蒸腾速率Tr分别提高37.5%、57.1%、74.4%、88.9%和52.3%,dV/dto(QA还原速率)降低了22.5%.[结论]叶面喷施SA可缓解盐胁迫对莴笋幼苗生长的抑制作用,提高盐胁迫下莴笋叶片可溶性蛋白、可溶性糖和脯氨酸的含量,降低MDA和相对电导率,增强光合能力.
Abstract
[Objective]To study the alleviate effect of salicylic acid(SA)on lettuce under saline stress and to provide a theoretical and technical basis for improving saline lettuce cultivation.[Method]No restric-tion of NaCl and no spraying of NaCl as control 1(CK1)and 200 mmol/L NaCl as control 2(CK2).Five SA treatments of foliar spray 0.1,0.3,0.6,1.2,2.4 mmol/L were set up to dynamically measure the growth and physiological related indexes of lettuce.[Result]Compared with the CK1 treatment,the CK2 treatment inhibited the growth of lettuce seedlings,reduced the accumulation of biomass and increased the content of soluble protein,soluble sugar and proline.Compared with CK2 treatment,foliar application of salicylic acid(0.6 mmol/L)at appropriate concentrations could reduce the inhibition of lettuce biomass accumulation in lettuce,promote the accumulation of soluble protein,soluble sugar and proline,and improve photosynthesis.Soluble sugar,soluble protein,net photosynthetic rate Pn,stomatic conductance Gs and transpiration rate Tr were increased by 37.5%,57.1%,74.4%,88.9%and 52.3%,respectively,while dV/dto(QA reduction ratio)was decreased by 22.5%.[Conclusion]Foliar application of SA alleviates growth inhibition of let-tuce plants under saline stress,increases soluble protein,soluble sugar and proline,reduces MDA and rela-tive conductivity,and increases photosynthetic capacity of lettuce leaves under saline pressure.
维普
万方数据