藜麦幼苗对混合盐碱胁迫的生理响应及耐盐碱性评价

Physiological response and evaluation to mixed saline-alkali stress of quinoa seedlings

试验旨在研究混合盐碱胁迫对不同藜麦品种幼苗生长发育和生理特性的影响。选择8个藜麦品种为材料,以清水(CK)为对照,选择两种碱性盐NaHCO_(3)、NaCO_(3),按照1∶1配成混合盐碱溶液,设置0.1、0.2、0.3 mol/L共3个浓度梯度的混合盐碱处理,测定其幼苗根长、株高及生理生化指标,并运用隶属函数法对不同藜麦品种的耐盐碱性进行综合评价。结果显示,随着处理盐浓度的增加,不同藜麦品种植株的生长均受到抑制。0.1 mol/L盐碱浓度处理有利于藜麦幼苗的生长发育,根长和株高较CK明显增加。与CK相比,低浓度盐碱胁迫提高了8份供试材料幼苗叶片叶绿素含量、抗氧化酶活性和渗透调节物质的含量;丙二醛(MDA)含量和超氧阴离子产生速率随着盐碱胁迫浓度升高呈现先降低后升高的趋势,活性氧代谢物的降低保护了植株的正常生长。研究表明,陇藜4号耐盐碱性最强,适宜在盐碱地种植,可以提高盐碱地利用率,陇藜5号次之,陇藜7号最弱。

The purpose of this experiment was to study the effects of mixed saline-alkali stress on the seedling growth and physiological characteristics of different quinoa varieties.Eight quinoa varieties were selected as materials,and water(CK)was used as the control.The two alkaline salts,NaHCO_(3) and NaCO_(3) were prepared into a mixed salt-alkali solution at the ratio of 1∶1,and the mixed salt-alkali treatment was set up with three concentration gradients of 0.1,0.2,and 0.3 mol/L.The root length,plant height and,physiological and biochemical indexes of the seedlings were measured.The salt and alkali tolerance of different quinoa varieties was evaluated by the membership function method.The results showed that with the increase of salt concentration,the growth of different quinoa varieties was inhibited.0.1 mol/L saline-alkali treatment was beneficial to the growth and development of quinoa seedlings,and the root length and plant height increased obviously compared with CK.Compared with CK,low concentration saline-alkali stress increased chlorophyll content,antioxidant enzyme activity,and osmotic adjustment substance content of seedlings of eight tested materials.Malondialdehyde(MDA)content and superoxide anion production rate decreased first and then increased with the increase of saline-alkali stress concentration,and the decrease of active oxygen metabolites protected the normal growth of plants.The study indicates that Longli No.4 has the strongest salt and alkali tolerance and is suitable for planting in saline-alkali land,which can improve the utilization rate of saline-alkali land,followed by Longli No.5 and Longli No.7.