盐胁迫下7个刺榆无性系的叶片生理变化与耐盐性评价

Physiological changes in leaves and evaluation of salt tolerance in seven clones of Hemiptelea davidii under salt stress

为研究不同NaCl盐浓度胁迫对刺榆无性系幼苗的叶形态、生理和光合指标的影响,探究刺榆耐盐的生理机制,文中采用盆栽法对7个刺榆无性系扦插幼苗进行4种浓度NaCl溶液处理,分析其叶片表型、生理指标和光合指标对不同NaCl盐浓度响应的差异。结果表明:1)刺榆各无性系在低浓度盐胁迫下均表现出较好的耐盐性;高浓度(100mmol·L^(-1)及以上)盐胁迫下刺榆各无性系的叶片边缘出现不同程度的萎蔫,且随着盐浓度增加,盐害症状逐渐加重。2)盐胁迫后,刺榆各无性系的光合速率随着盐浓度的升高均呈下降趋势。3)刺榆各无性系的相对电导率、丙二醛含量均随盐胁迫浓度增加而呈现不同程度升高,5个刺榆无性系的超氧化物歧化酶、过氧化物酶、过氧化氢酶等抗氧化酶活性以及脯氨酸、可溶性糖等渗透调节物质含量均呈现为持续增高趋势,2个无性系呈现为先上升后下降的趋势。4)隶属函数法和聚类分析结果显示,各无性系的耐盐能力由强到弱依次为DJ1>DJ3>DJ2>DH1>DJ4>DW1>DY1,其中DJ1与DJ3为强耐盐型,DJ2为较强耐盐型,DH1与DJ4为中等耐盐型,DW1与DY1为弱耐盐型。文中研究结果为深入研究刺榆耐盐生理机制和耐盐种质资源创新利用提供依据。

In order to investigate the effects of different NaCl salt concentrations on the leaf morphology,physiological and photosynthetic indicators in seven clones of Hemiptelea davidii,and to explore the physiological mechanism of salt tolerance in H.davidii,this study used a potted method to treat seven clones of H.davidii with four different concentrations of NaCl solution,and analyzed the differences in leaf morphology,physiological indicators,and photosynthetic indicators in response to different NaCl salt concentrations.The results showed that:1)Under the different concentrations of NaCl stresses,all clones of H.davidii exhibited salt tolerance under the stress of low concentration of salt.Under high concentration(100 mmol·L^(-1)and above)of salt stress,the leaf edges in various clones of H.davidii exhibited varying degrees of wilting,and as the salt concentration increased,the symptoms of salt damage were gradually worsened.2)After salt stress,the photosynthetic rate of various clones of H.davidii showed a decreasing trend with the increase of salt concentration.3)The relative conductivity and malondialdehyde content of various clones of H.davidii showed varying degrees of increase with the increase of salt concentration.The activities of antioxidant enzymes such as superoxide dismutase,peroxidase,catalase,as well as osmotic regulatory substances such as proline content and soluble sugar content of five clones of H.davidii showed a continuous increasing trend,while the other two clones showed a trend of first increasing and then decreasing.4)The results of membership function and cluster analysis indicated that,according to the salt tolerance of seven clones of H.davidii from strong to weak,they were ranked as DJ1>DJ3>DJ2>DH1>DJ4>DW1>DY1.Among them,DJ1 and DJ3 were the type with the strongest salt tolerance,DJ2 was the type with stronger salt toleranve,DH1 and DJ4 were the type with moderate salt tolerance,and DW1 and DY1 were the type with weak salt tolerance.This study provides a basis for in-depth research on the physiological mechanism of salt tolerance and innovative utilization of salt tolerant germplasm resources in H.davidii.