脱落酸与胡杨抗盐性的关系

Salt Resistance in Relation to ABA In P euphratica

为模拟胡杨根系受盐胁迫时引起ＡＢＡ水平上升的生理作用，用一定浓度的ＮａＣｌ，ＡＢＡ和玉米素单独和联合施入胡杨的根系环境，发现：ＡＢＡ处理和ＮａＣｌ处理都能迅速引起气孔阻力上升，并且两者的作用有加合性．与ＮａＣｌ处理相比，ＮａＣｌ＋ＡＢＡ处理的胡杨吸收离子减少，而吸收钾和钙离子增加．说明ＡＢＡ作为盐胁迫的调控信号能引起膜结构变化，改善选择吸收功能，从而拮抗盐离子的有害影响．玉米素的作用与ＡＢＡ的作用恰好相反．

By applying exotic ABA and zeatine,it was found that P euphr-atica could reduce salt influx in two ways after sensing salt stress:①closing stomatal could reduce transpiration and therefore reduce ion influx by mass flow;②enforcing ion selectivity could reduce ion influx of harmful elements and increase ion influx of nutritional elements,which would alleviate salt stress Furthermore,Ca 2+ contents in xylum sap under ABA treatment were 6times as much as that under control,indicating that P euphratica could transport more Ca 2+ to leaf under stress condition The high concentration of Ca 2+ can maintain membrane integrity in one hand,and induce closure of stomatal in the other hand Thus it can be concluded that Ca 2+ is a salt resistance signal for P euphratica