【作者】 祁向玲；

【导师】 邹志荣；

【作者基本信息】 西北农林科技大学 ， 蔬菜学， 2008， 硕士

【摘要】 土壤盐渍化是影响作物生长的一个重要问题,如何解决土壤盐渍化问题已成为国际上和生物科学技术迫切需要解决的重大课题,设施栽培的特点是采用人工措施改变局部的生态环境,对提高蔬菜的产量和品质起着重要的作用,但是由于栽培、水肥管理的不科学,土壤盐分表积现象严重,发生保护地次生盐渍化,给生产造成了很大的影响。本试验在前人关于外源物质对植物盐胁迫的缓解作用的研究基础上,模拟盐渍化土壤中盐分胁迫状况,以砂培生菜(Lactuca sativa L.)(品种为耐盐品种:香港玻璃生菜和盐敏感品种:美国大速生)为试材,分别喷施三种外源物质:水杨酸(SA)、氯化钙(CaCl2)和5-氨基乙酰丙酸(ALA)为处理,喷施自来水作为对照,研究了不同盐浓度及外源物质处理对生菜生长、抗氧化保护系统及生理生化指标的影响及并同时研究了外源物质缓解盐胁迫的作用机理,主要研究结果如下:1、外源ALA、SA、CaCl2对盐胁迫下生菜植株生理特性的影响对于耐盐品种香港玻璃生菜,在0mmol/LNaCl胁迫下,ALA的增产效果最佳,其比对照单株产量增加了50.1%,并使电导率显著降低,生菜叶片中可溶性蛋白含量及植株的根系活力显著增加,CaCl2显著增加了叶片中叶绿素含量。对于盐敏感品种美国大速生,在100mmol/LNaCl胁迫下,ALA的增产效果最佳,其比对照单株产量增加了69.5%, ALA显著降低了叶片电导率,显著增加了可溶性蛋白含量及植株的根系活力,SA也显著降低了盐胁迫下叶片的相对电导率值,提高叶片中叶绿素含量,CaCl2显著提高了生菜植株的根系活力。总之,从植株的产量、形态及各项生理指标的数据来看,三个外源物质中ALA效果最佳,CaCl2及SA次之。2、外源ALA对生菜盐胁迫的缓解效应外源ALA能显著提高生菜的总产量,对于耐盐品种香港玻璃生菜,在0～150mmol/LNaCl胁迫下,小区总产量分别比对照提高了32.6%、16.7%、29.8%、34.5%;而对于盐敏感品种美国大速生,产量分别增加了20.9%、11.5%、62.4%、25.7%。ALA能显著的降低生菜叶片的相对电导率,缓解生菜在盐胁迫下的受害程度,并且这种作用效果在生菜生长的后期更显著。在100mmol/LNaCl胁迫下,ALA处理显著的抑制了生菜叶片中MDA的合成,且在ALA的处理后期效果显著。ALA处理对保护酶系统的影响也较大,ALA对耐盐品种在高盐胁迫下增强SOD活性的效果较显著,而对盐敏感品种在低盐胁迫下作用效果较强,对盐敏感品种在50mmol/L及100mmol/LNaCl胁迫下增加CAT活性作用效果显著。ALA也增加了耐盐品种0～100mmol/LNaCl盐胁迫下植株POD活性,而对盐敏感品种在100mmol/LNaCl胁迫下的植株效果显著,且在后期效果更佳。ALA处理也显著的增加生菜叶片中叶绿素的含量及蔬菜品质。总的来说,ALA对提高盐胁迫下生物产量、改善植株的形态、影响生理指标及提高生菜的蔬菜品质都有显著效果,并且在ALA处理后期及0～100mmol/LNaCl胁迫下效果更显著。更多还原

【Abstract】 Soil salinization is an important factor that can affect crop growth. How to settle soil salinization has become a significant problem, which is not only international, but also wrgency in biological technology. The trait of agritechnology is adopting man-made measure to alter pary environment, which will greatly improve the yield and quality of vegetable .But because it’s not very scientific of culture, water and fertilizer, the phenomenon of salinity accumulation is so apparent. That causes soil salinization of sheltered farmland, which severely affects the production.On the basis of the research on mitigative effects of exogenous materials in the vegetation under salt stress , the experiment simulates salinity of soil salinization Lettuce(Lactuca sativa var.capitata L.) was used to study the effects of exogenous materials,the lettuce(salt-tolerant:Xiang gang bo li sheng cai;Salt-sensitive:Mei Guo da su sheng)as the marterial in the experiment. SA, CaCl2 and AlA were Spurting as the different treatments and Spurting water as the CK. The Lettuce growth and antioxidation protective and physiological metabolism were studied in the experiment and the main results as follows:1. The effect of Exogenous ALA, SA, CaCl2 on physiological characteristics of Lettuce under Salt Stress.For the salt-tolerant Variety-Xiang Gang bo li sheng cai: the single yield was increased by 50.1% than CK under non-salty stress after used exogenous ALA; The conductivity was reduced, the content of chlorophyll and solution protein,root activity was increased after used Exogenous ALA; And the content of chlorophyll was increased after used Exogenous CaCl2.For the Salt-sensitive variety-Mei Guo da su sheng: the single yield was increased by 69.5% than CK under 100mmol/L NaCl stress after used exogenous ALA; The conductivity was reduced, the content of solution protein, root activity was increased after used Exogenous ALA; And the conductivity was reduced, the content of chlorophyll was increased after used Exogenous SA; The root activity was increased after used Exogenous CaCl2. In a word, ALA of the three Exogenous materials has the best effect of Mitigative effact of salt stress with increased the yield and changed plant shape, physiological and biochemical characteristic than SA and CaCl2.2. Mitigative Effect of Exogenous ALA on Lettuce under salt stress. For the salt-tolerant Variety-Xiang Gang bo li sheng cai: the yield was increased by 32.6%, 16.7%, 29.8%, 34.5% than CK under 0～150mmol/L concentration of NaCl stress after used exogenous ALA; For the Salt-sensitive variety-Mei Guo da su sheng: the yield was increased by 20.9%,11.5%,62.4%,25.7% than CK under 0～150mmol/L concentration of NaCl stress after used exogenous ALA. The conductivity reduced, so the salt stress was weakened with ALA, and the effect of ALA was better in the later stage of lettuce grown. The content of MDA under 100mmol/L concentration of NaCl stress, and the effect was notable in the later stage of grown. Antioxidation protective was also changed after used ALA, the SOD activity increased with ALA treated in the later stage of grown for salt-tolerant variety under high salt stress, but it has better action for Salt-sensitive variety under low salt stress. The CAT activity increased with ALA treated for salt-tolerant Variety under 50mmol/L and 100mmol/L concentration of NaCl stress. The POD activity increased with ALA treated for salt-tolerant Variety under 0～100mmol/L concentration of NaCl stress, and ALA had notable affect of salt-sensitive variety under 100mmol/L concentration of NaCl. The content of chlorophyll and the quality of vegetables were increased after treated used ALA In a word, the yield increased, plant shape improved,physiological characteristic changed and vegetable quality increased with ALA treated, and in the later stage under 0～100mmol/L concentration of NaCl with ALA treated had better effects.更多还原