黑豆根尖边缘细胞对盐胁迫的防护效应

采用振荡培养(移除根尖边缘细胞)和静置培养(保持边缘细胞附着在根尖)方法,对比研究盐胁迫对黑豆根系生长和根尖边缘细胞发育、根系Na+、K+含量的影响以及根系生理特性的变化。结果显示:100和200 mmol.L-1NaCl处理抑制边缘细胞发育,引起根系相对电导率和MDA含量增加。振荡培养去除根尖边缘细胞处理36 h,黑豆根相对伸长率、根尖K+含量明显低于对应NaCl浓度的静置培养处理,同时根尖Na+含量、相对电导率和MDA含量在去除边缘细胞后显著增加。说明包裹于根尖的边缘细胞通过调节Na+和K+的吸收和维持较高的细胞膜完整性,以适应盐害环境。

Protective Effect of Root Border Cells on Salt Stress in Black Soybean

The effects of salt stress on root growth,root border cells(RBCs)development,Na+ and K+ content and physiological characteristic in black soybeanGlycine max(L.)Merrill]were investigated,with RBCs adhered to root tips using a static cultivation method,or with RBCs removed from root tips using a shaking cultivation method.Salt stress treated with 100 and 200 mmol·L-1NaCl inhibited RBCs development and increased relative electric conductivity and MDA content in roots.Physical removal of RBCs from root tips for 36 h resulted in a more severe inhibition of root elongation and a higher Na+ accumulation in the root tips,the relative electric conductivity and MDA content in roots were also significantly increased when RBCs were removed.The results revealed that RBCs adhered to the root tips tended to regulate the uptake of Na+ and K+,and maintain cell membrane integrity,thereby increased salt tolerance in black soybean seedlings.