盐胁迫预处理对大麦根尖分生区细胞超微结构的影响

EFFECT OF IMBIBITION UNDER SALT STRESS ON MERISTEMATIC CELL ULTRASTRUCTURE IN ROOT TIPS OF BARLEY

盐胁迫吸胀后的大麦种子转入正常条件下萌发，其发芽势严重降低，发芽率则和对照差异不大。电镜观察表明，萌发３天的大麦根尖分生区细胞膜系统已修复完善，内质网和高尔基体丰富，变形质体和变形线粒体大量出现。表明短时盐胁迫对种子萌发的抑制作用是可逆的，而且一旦抑制作用被解除，植物细胞内的生理代谢活动会更加活跃，这一现象称为“抑制效应的补偿作用”。由于盐胁迫吸胀后代谢加强总伴随着变形质体和变形线粒体的大量出现。因此，我们推测，变形质体和变形线粒体很可能是因代谢活动加强而出现的一种适应形式。

The barley(Hordeum vulgare L.)seeds were germinated in the normal conditions after 12hours imbibition under salt stress. The results showed that(1)The germination energy was verylow while the germination percentage was as high as that of control seeds;(2)The restoration ofmembrane system was perfect;(3)Plenty of endoplaqmic reticulum and Golgi body appeared;and(4)There were also increases in the quantities of amoeboid plastids and amoeboid mitochondriawhich were so called because of its same shape to amoeboid plastids. The facts suggested that theinhibitory effect of short- term salt stress on plants was reversible and it enhanced the metabolicactivities in cells as soon as the salt stress was removde,which was interpreted as a compensation’for the inhibitory effect. It was supposed that the amoeboid may be an adaption form of plastids or mitochondria to anenhanced metabolic activity since plenty of amoeboid plastids and amoeboid mitochondria ap-peared when the metablic activity increased in cells.