摘要
【目的】明确根边缘细胞与根对铝敏感性差异及其与细胞壁多糖组分含量的关系。【方法】以中豌五号为材料,采用雾培法,研究铝胁迫下豌豆根边缘细胞和根细胞壁多糖组分含量的变化。【结果】在4.0mmol·L-1AlCl3处理24h后,边缘细胞活性显著降低,细胞活性抑制率达到了19.2%,根系相对伸长的抑制率为10.1%。无铝条件下,边缘细胞的细胞壁果胶、纤维素糖醛酸和总糖含量显著高于根段细胞壁。4.0mmol·L-1A1C13处理后,豌豆0～10mm和10～20mm根段细胞壁果胶糖醛酸含量提高,边缘细胞提高幅度尤为明显;边缘细胞果胶总糖含量显著提高,半纤维素和纤维素总糖显著降低,而2个根段细胞壁果胶、半纤维素和纤维素总糖含量提高。边缘细胞果胶、半纤维素和纤维素的铝含量显著高于0～10mm和10～20mm根段,0～10mm根段铝含量高于10～20mm,且在4.0mmol·L-1A1C13处理24h后边缘细胞果胶1铝含量分别是0～10mm、10～20mm根段的14.4和17.4倍;同时,边缘细胞细胞壁半纤维素和纤维素多糖较果胶高,且含有相当量的铝。【结论】豌豆根边缘细胞细胞壁果胶含量显著高于2个根段,与铝含量呈显著正相关,显示果胶含量高的边缘细胞与根尖相比对铝毒更为敏感,同时,边缘细胞细胞壁多糖(包括果胶,纤维素和半纤维素)可能与铝的结合有重要作用。
[Objective] Root border cells are released from root apices of most plant species, and the root tip is the target of A1 toxicity, thus it was presumed that border cells might be more sensitive to A1 toxicity than root cells. The objective of the present study is therefore to investigate the differences in cell wall polysaccharides between border cells and root apices of pea （Pisum sativurn） under A1 exposure. [Method] The root border cells of pea （Pisum sativum） were cultivated by mist containing different levels of A1 in 24℃ growth chamber for 24 h after seed soaking. [ Result] Results showed that the viability of border cells was significantly decreased by the 4.0 mmol.L^-1 AlCl3 treatment, and the inhibitory rate of the viability of border cells was 19.2 % and the inhibitory rate of relative root elongation was 10.1% after 24 h treatment of 4.0 mmol.L^-1 AlCl3. The uronic acid and sugar contents of pectin and cellulose in border cell walls were significantly （P〈 0.05） higher than in the root segments of 0-10 mm and 10-20 mm at the absence of A1. The uronic acid content of pectin in border cell walls increased obviously related to the root segments of 0-10 mm and 10-20 mm at 4.0 mmol.L^-1 AlCl3. The sugar content of pectin in border cell walls was increased significantly （P〈0.05）, but decreased seriously in hemi-cellulose and cellulose at 4.0 mmol.L^-1 AlCl3. The A1 content of pectin, hemi-cellulose and cellulose in the border cell walls were significantly （P〈0.05） higher than in the root segments of 0-10 mm and 10-20 mm. A1 contents of pectin 1 in the border cell walls were 14.4 arid 17.4 fold to that in the root segments of 0-10 mm and 10-20 mm at 4.0 mmol.L^-1 AlCl3, respectively, and the A1 content in the root segments of 0-10 mm was higher than in the 10-20 mm; at the same time, hemi-cellulose and cellulose, the major compositions of cell wall, contained more AI than pectin. [Conclusion] These results indicated that the contents orAl binding to cell walls is related to the contents of pectin in cell walls and the border cells were more sensitive to A1 than the root segments of 0-10 mm and 10-20 mm. Cell wall polysaccharides including pectin, hemi-cellulose and cellulose might play important roles in binding A1 in border cell walls.
出处
《中国农业科学》
CAS
CSCD
北大核心
2009年第6期1963-1971,共9页
Scientia Agricultura Sinica
基金
国家自然科学基金项目(30200167
30471035)
广东省自然科学基金项目(06029443)
关键词
豌豆
边缘细胞
铝毒
细胞壁多糖
敏感性
pea （Pisum sativum）
border cells
al toxicity
cell wall polysaccharides
sensitivity
