摘要
为探讨镧对NaCl胁迫下柳枝稷种子萌发及幼苗生理特性的影响,该研究以柳枝稷(Panicum virgatum L.)种子为研究材料,通过不同浓度(0、0.05、0.1、0.5和1.0mmol/L)La(NO3)3溶液浸种24h处理后,添加100mmol/L NaCl溶液,以蒸馏水为对照,在种子发芽箱中培养并观察柳枝稷种子萌发和幼苗生长,测定幼苗叶片相对电导率、丙二醛、脯氨酸和叶绿素的含量。结果显示:(1)0.05mmol/L La(NO3)3浸种处理可缓解100mmol/L NaCl对种子发芽的影响。(2)不同处理对幼苗苗长无显著影响,0.1mmol/L La(NO3)3浸种显著增加了幼苗的鲜重和叶面积,当浓度≥0.5mmol/L时根长、根冠比、鲜重和叶面积受到抑制。(3)幼苗叶片相对电导率和脯氨酸含量随La(NO3)3浓度的增加呈先降低后增加的趋势,其中0.05和0.1mmol/L La(NO3)3浸种处理下效果较好,丙二醛含量随La(NO3)3浓度的增加持续降低,但各浓度处理间差异不显著,叶绿素含量在0.05mmol/L La(NO3)3浸种处理下较NaCl处理显著增加,当浓度≥0.5mmol/L随着浸种浓度的增加呈下降趋势。(4)不同指标间发芽势与发芽率、根长和叶绿素含量间呈极显著正相关关系,与根冠比、电导率和脯氨酸含量均呈极显著负相关关系,而与苗长不相关。研究表明,低浓度(0.05mmol/L)La(NO3)3可缓解NaCl胁迫对柳枝稷种子萌发及幼苗生长的影响,而高浓度(1.0mmol/L)的La(NO3)3则会加重NaCl的胁迫危害。
To investigate the effect of La（NO3）3 on seed germination and seedling growth characterlstics ot switchgrass（Panicum virgaturn L. ） under NaCl stress,we measured seed germination, seedling growth, relative electrical conductivity, MDA, proline and chlorophyll contents in incubator. Seeds were soaked in different concentrations （0,0.05,0. 1,0.5 and 1.0 mmol/L） of La（NO3）3 for 24 h,and then added 100 mmol/L NaC1 solution, with distilled water as control. The results showed that： （1）0. 05 mmol/L La （NO3）3 could relieve 100 mmol/L NaCl effect on seed germination; （2）There was no significant effect on shoot length with different treatments,but 0. 1 mmol/L La（NO3）3 treatment significantly increased thefresh weight and leaf area of seedlings. When the concentrationS0.5 mmol/L,root lengm,root snoot rati- o, fresh weight and leaf area were all inhibited significantly; （3）The relative electrical conductivity and pro- line content of seedling leaves decreased firstly and then increased with increasing La（NOa）a concentration, of which 0.05 and 0.1 mmol/L La（NO3）3 treatment were better,the MDA content increased with increas- ing La（NOa）a concentration has been reduced. The chlorophyll content increased with 0.05 mmol/L La （NO3）3 treatment comparing with NaCl,and decreased with increasing La（NO3）3 concentration. However, there were no significant difference among different concentration treatments. （4）Different factors between the germination potential and germination rate, had a significantly positive correlation between root length and chlorophyll content,and had a significantly negative correlation with the root shoot ratio, relative elec- trical conductivity, and proline content. However,it was no significant correlation between germination po- tential and shoot length. This research indicated that low concentration （0.05 mmol/L） of La（NO3）3 could alleviate NaCl stress,high concentration （1.0 mmol/L） of La（NO3）3 could increase the stress.
出处
《西北植物学报》
CAS
CSCD
北大核心
2014年第3期543-549,共7页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家"十二五"科技支撑计划(2011BAD17B05)
中央高校基本科研业务费(Z109021205)
西北农林科技大学博士科研启动基金(Z109021111)
关键词
硝酸镧
盐胁迫
柳枝稷
种子萌发
幼苗生长
生理特性
La （NO3） 3
salt stress
switchgrass
seed germination
seedling growth
physiological characteris-tics
