黑豆边缘细胞对干旱胁迫的响应和对根系生理特性的影响  

Response of root border cells to drought stress and their effects on physiological characteristics of roots of black soybean seedlings

作　　者：邢承华[1] 吴韶辉[2] 梅忠[1] 陈雪[1] 罗小会[1] 

机构地区：[1]金华职业技术学院农业与生物工程学院,浙江金华321007 [2]浙江省柑橘研究所,浙江台州318020

出　　处：《植物营养与肥料学报》2012年第2期332-337,共6页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金资助项目(30800705;31101599);金华职业技术学院国家自然科学基金预研项目(2010G001);浙江省自然科学基金项目(Y3110561;Y307535)资助

摘　　要：以黑豆Glycine max(L.)Merrill为材料,采用静置培养(保持边缘细胞和黏液附着在根尖)和振荡培养(移除边缘细胞及根尖黏液)的方法,比较研究干旱胁迫下黑豆根尖边缘细胞(root border cells,RBCs)产生和黏液分泌以及对根系生理特性的影响。结果表明,与对照相比,11%和22%的聚乙二醇(PEG)处理使RBCs数目分别降低了18.1%～21.6%和28.8%～30.4%,胞外黏液分泌量分别增加了62.8%～140.7%和133.8%～172.7%,表明干旱胁迫抑制了RBCs的发育,增加了RBCs黏液分泌量。移除边缘细胞的根伸长抑制率、根系相对电导率和丙二醛(MDA)含量高于保留边缘细胞的根,而根系脯氨酸含量则是前者显著低于后者。说明干旱胁迫下,黑豆根尖附着的RBCs及黏液分泌量的增加,减缓了根尖细胞损伤,有利于根系生长,从而提高了黑豆的抗旱能力。Root border cells and root cap cells secrete mucilage into root rhizosphere which acts as a chemical, physical and biological interface between roots and their surrounding environment. The effects of root border cells （RBCs） and root mucilage on protection of roots from drought stress were carried out by two cultivation methods, a shaking cultivation method to remove RBCs from root tips and a static cultivation method to maintain RBCs adhered to the root tips. Compared to the control, the root border cells nomber are decreased by about 18.1% -21.6% and 28. 8% -30. 4%, respectively under the treatments of the roots with 11% and 22% PEG, while the thicknesses of the mucilage layer around RBCs are increased by about 62. 8% - 140. 7% and 133.8% - 172.7%. These results suggest that the drought stress inhibits RBCs development and enhances mucilage secretion. The physical removal of RBCs from root tips results in a more severe drought-induced inhibition of root elongation, relative electric conductivity and malondialchehyche （MDA） content. The proline content in roots of black soybean with RBCs removed is significantly lower than that in roots with RBCs surrounding. These results suggest that RBCs adhered to the root tips tend to enhance RBCs＇ mucilage secretion, decrease the damage to root cells, promote root growth, and thereby promote drought tolerance in black soybean seedlings.

关 键 词：黑豆 边缘细胞 干旱胁迫 黏液 生理特性 

分 类 号：S529[农业科学—作物学]