植物学报 ›› 2010, Vol. 45 ›› Issue (01): 73-78.DOI: 10.3969/j.issn.1674-3466.2010.01.010

• 研究报告 • 上一篇    下一篇

海水胁迫对苦荬菜幼苗生长及生理特性的影响

李洪燕, 郑青松, 刘兆普*, 李青

  

  1. 南京农业大学资源与环境科学学院, 江苏省海洋生物学重点实验室, 南京 210095
  • 收稿日期:2009-05-19 修回日期:2009-07-09 出版日期:2010-01-01 发布日期:2010-01-01
  • 通讯作者: 刘兆普

Effects of Various Concentration of Seawater on the Growth and Physiological Characteristics of Lactuca indica Seedlings

Hongyan Li, Qingsong Zheng, Zhaopu Liu*, Qing Li   

  1. Key Laboratory of Marine Biology in Jiangsu Province, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China
  • Received:2009-05-19 Revised:2009-07-09 Online:2010-01-01 Published:2010-01-01
  • Contact: Zhaopu Liu

摘要:

抗盐耐海水植物的种植是有效利用和开发滩涂资源的措施之一。采用温室砂培方式, 研究了不同稀释配比的海水处理8天对苦荬菜(Lactuca indica)幼苗生物量、根冠比、叶绿素含量、离子含量、可溶性蛋白和可溶性糖含量的影响。结果表明: 苦荬菜幼苗地上部受海水胁迫较为显著, 而根在海水浓度小于30%时与对照相比没有显著差异; 根冠比随着海水浓度的增加而不断提高; 在10%和20%海水浓度处理下, 叶绿素含量与对照相比差异不显著, 但随着海水浓度的进一步增加,叶绿素含量显著下降; 在10%海水浓度处理下, 苦荬菜地上部分及根部的K+含量与对照相比差异不显著, 而海水浓度高于10%时, 随着海水浓度的增加地上部和根部的K+含量均逐渐降低; 海水处理下, 苦荬菜体内Na+和Cl含量逐渐增加; 地上部可溶性糖含量逐渐增加, 而可溶性蛋白含量先升后降。海水胁迫下, 苦荬菜幼苗维持一定的K+选择性吸收是其一定程度上盐适应的重要原因。同时, 积累的可溶性糖和可溶性蛋白是苦荬菜幼苗在盐胁迫下的重要渗透调节物质, 可作为其抗盐性的生理参数。

Abstract:

Planting of salt-tolerant plants is vital for the development of available coastal land resources. We studied the effects of different concentrations of seawater (diluted in 1/2 Hoagland’s solution) on the biomass and chlorophyll, ion, soluble sugar and soluble protein contents of Lactuca indica seedlings by sand culture in the greenhouse. The dry weight of L. indica shoots was more susceptible to seawater stress than that of roots. Compared with dry weight of controls, that of roots of L. indica seedlings was unchanged with seawater concentrations from 10% to 30%. With increasing seawater stress, the ratio of roots to shoots and Na+, Cl and soluble sugar contents were increased significantly. With 10% and 20% seawater treatments, chlorophyll content did not differ from that of controls but was significantly decreased with further increased seawater stress. At a seawater concentration of 10%, K+ content in the shoots and roots of L. indica seedlings did not differ from that of controls, but with increased seawater stress, the K+ content was markedly dose-dependently decreased. However, as gradually increasing soluble sugar content significantly, soluble protein content first increased then decreased with increasing seawater concentration. Adaptation to seawater in L. indica was mainly caused by strong K+ selective absorption and transport. Furthermore, accumulating soluble sugar and protein were important osmotica in L. indica seedlings and could be an indicator of salt tolerance.