不同浓度亚精胺对盐胁迫下黄瓜幼苗的生长影响
时间:2018-07-26 21:29 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本研究以盐敏感型黄瓜品种‘津优4号’为试验材料，采用了营养液栽培方式，通过在营养液中直接添加不同浓度的外源亚精胺( Spd )研究其对75 mmol/L NaCl胁迫下黄瓜幼苗生长及光合作用的影响，筛选出能缓解盐胁迫伤害的最适外源亚精胺浓度。结果表明，经浓度为75 mmol/L NaCl胁迫处理3天的黄瓜幼苗与对照相比受到显著的抑制作用，而添加不同浓度的外源Spd（0.05 ~ 0.15 mmol/L）可不同程度地缓解盐胁迫所造成的伤害，其中以0.1 mmol/L Spd效果最为显著，能显著提高盐胁迫下黄瓜幼苗的生长指标、叶绿素含量和气体交换参数，而Spd浓度过高（0.15mmol/L）或者过低（0.05mmol/L）对盐胁迫下黄瓜幼苗的茎粗、地上部与地下部鲜重、地上部干重、叶绿素b含量及胞间二氧化碳浓度的缓解效果不显著。总之，适当浓度的外源亚精胺可缓解黄瓜幼苗的盐胁迫伤害，促进盐胁迫条件下黄瓜幼苗的光合作用，促进植株的生长。26234 毕业论文关键词：亚精胺；盐胁迫；黄瓜幼苗；光合作用；生长 Effects of exogenous spermidine on growth and photosynthesis of cucumber seedlings under NaCl stress Facilities agriculture science and engineering Li Yanan Tutor Shi Haixian Abstract：In this study, salt sensitive cucumber cultivar 'Jinyou No. 4' was selected as experimental material, the cultivation method of nutrient solution, by directly adding different concentrations of exogenous in nutrient solution of spermidine (Spd) to study its effect on the 75 mmol/L NaCl stress on growth and photosynthesis of cucumber seedlings under the screen can alleviate the most suitable exogenous spermidine concentration of salt stress. The results showed that the concentration of 75 mmol/L NaCl stress for 3 days compared with the control of cucumber seedlings was significantly inhibited, and the addition of different concentrations of exogenous Spd (0.05~0.15 mmol/L) can alleviate the salt stress caused by injury, of which 0.1 mmol/L Spd was the most significant effect, can significantly improve the growth index, chlorophyll content of cucumber seedlings under salt stress and gas exchange parameters, and the high concentration of Spd (0.15mmol/L) or low concentration of Spd (0.05mmol/L) to cucumber seedlings under salt stress, the stem diameter of shoot and root fresh weight, shoot dry weight, chlorophyll b content and alleviate the effect of intercellular CO2 concentration is not significant. In a word, proper concentration of exogenous spermidine could alleviate the salt stress injury of cucumber seedlings, and promote the photosynthesis of cucumber seedlings under salt stress and promote the growth of plants. Key words: spermidine；cucumber seedlings；photosynthesis；growth；NaCl stress 目 录 摘要1 关键词1 Abstract1 Key words1 引言1 1 材料与方法2 1.1 材料与方法 2 1.1.1 试验材料 2 1.1.2 试验方法2 1.2 测定指标2 1.2.1 生长指标2 1.2.2 叶绿素含量2 1.2.3 气体交换参数3 2 结果与分析3 2.1 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗生长状况的影响 3 2.2 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗叶绿素含量的影响 3 2.3 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗气体交换参数的影响 4 3 讨论4 致谢5 参考文献6 表1 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗生长状况的影响3 表2 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗叶绿素含量的影响4 图1 不同浓度外源亚精胺对盐胁迫下黄瓜幼苗气体交换参数的影响4 不同浓度亚精胺对盐胁迫下黄瓜幼苗的生长的影响 近年来，我国在农业领域发展迅速，逐渐成为设施农业发展大国，然而中国人口不断增多相对的可供种植的土地面积却在不断减少，土地利用率越来越高，加上土壤灌溉施肥方式不合理等因素所造成的土壤盐害、虫害及一些土壤连作障碍现象在不断加重。其中土壤盐害是影响作物生产的主要限制因素之一[1]，研究结果表明，植物的光合作用对盐胁迫是敏感的，一定程度的盐胁迫会使黄瓜幼苗的气孔关闭、叶绿素含量下降、胞间CO2浓度降低等[2]，从而使植物的光合速率下降，其生长发育也会受到明显的抑制[3]，土壤中过高的盐分会对作物造成株高降低、叶面积变少、产量减少、口感不佳等影响[4]，无法体现出设施农业栽培的优势，不利于农业设施内种植的进一步发展。 (责任编辑：qin) |