边缘细胞对大豆根尖铝毒害的缓解效应  

Border Cells Alleviating Aluminum Toxicity in Soybean Root Tips

作　　者：李荣峰[1] 蔡妙珍[1] 刘鹏[1] 徐根娣[1] 梁和[2] 周主贵[2] 

机构地区：[1]浙江师范大学植物学重点实验室,浙江金华321004 [2]广西大学农学院,广西南宁530005

出　　处：《作物学报》2008年第2期318-325,共8页Acta Agronomica Sinica

基　　金：国家“十五”科技攻关计划项目(2004BA52506);国家自然科学基金项目(30540056);浙江省自然科学基金项目(304185,303461)

摘　　要：以大豆[Glycinemax(L.)Merrill]浙春3号为试验材料,采用静置培养(保持边缘细胞附于根尖)和振荡培养(移除根尖边缘细胞),测定边缘细胞数目和活性、根相对伸长率和根内酶的活性,研究了边缘细胞对大豆根尖铝毒害的缓解效应。结果显示,大豆发育过程中存活的边缘细胞数与总数之比达60%～80%,50～400μmolL-1 Al3+胁迫12h能诱导边缘细胞从根尖脱落,200～400μmolL-1 Al3+胁迫24h对边缘细胞的发育有抑制作用。Al3+处理抑制根伸长,移除边缘细胞的根相对伸长率低于保留边缘细胞的根。0～100μmolL-1 Al3+胁迫12h,0和50μmolL-1 Al3+胁迫24h,具有边缘细胞的大豆根系的POD、SOD活性及蛋白质含量显著高于移除边缘细胞的根内酶活性和蛋白质含量,但200和400μmolL-1 Al3+处理12h,100～400μmolL-1 Al3+处理24h时,根尖有无边缘细胞对根系的酶活性及蛋白质含量影响不显著。说明低浓度Al3+胁迫下,大豆通过增加边缘细胞数目、提高根尖蛋白质含量,维持较高水平的POD、CAT和SOD活性来对抗铝毒胁迫,以缓解植物的铝毒害。Root border cell （BC） is a group of cells from the apex of root, which has been considered to play a vital role in protecting root tip from extracellular biotic and abiotic stresses. It is known that the BC may secrete saccharide to chelate Al^3＋ and alleviate cell damage under aluminum stress. In this paper, we aimed to reveal the effects of root BC on alleviation of aluminum toxicity to root tips with soybean [Glycine max （L.） Merrill] cultivar Zhechun 3 during the development of roots. The BC number, activities of peroxidase （POD）, catalase （CAT）, and superoxide dismutase （SOD） as well as protein content were measured under 0 （CK）, 50, 100, 200, and 400μmol L^-1 Al^3＋ stress for 12 and 24 h respectively, with static culture （to maintain border cells adhered to root tips） and shaking culture （to remove border cells from root tips completely）. The results showed that the viable border cells accounted for 60%-80% when root length was 5 mm. 50-400 μmol L^-1 Al^3＋ treatment for 12 h increased the number of border cells, but inhibition of border cell development by Al^3＋ turned up after 200, 400 μmol L^-1 Al^3＋ treatment for 24 h. When soybean roots were cultivated by shaking to remove border cells from root tips, root elongation was decreased with increasing Al^3＋ concentrations. However, this kind of inhibition of root growth was alleviated under static culture. At the same time, POD, CAT （under Al stress for 12 h）, SOD activities and protein content were higher significantly than those under shaking culture withlower Al^3＋ concentration （0-100 μmol L^-1 Al^3＋ treatment for 12 h and 0, 50 μmol L^-1 Al^3＋ treatment for 24 h） stress. And no significant difference in POD, SOD activities and protein content was observed between static culture and shaking culture under higher Al^3＋ concentration （200, 400 μmol L^-1 Al^3＋ treatment for 12 h and 100-400 μmol L^-1 Al^3＋ treatment for 24 h） （P〉0.05）. The results suggested that border cells adh

关 键 词：边缘细胞 大豆 铝毒 缓解效应 

分 类 号：S565.1[农业科学—作物学] X173[环境科学与工程—环境科学]