NaCl胁迫对黄瓜根系边缘细胞发生的影响

Effects of NaCl Stress on Generation of Root Border Cells in Cucumber (Cucumis sativus L.)

以黄瓜为试材,研究了NaCl处理对植株生物量、根长、根系活力、根边缘细胞的数目和活性及黏胶层厚度的影响。结果表明,NaCl处理降低了植株生物量与根系长度,增加了黄瓜幼苗的根系活力。黄瓜边缘细胞的出现几乎与根同时发生,当根长达到25mm时,边缘细胞的数目与活性均达到最大值。NaCl处理对边缘细胞的数目与活性表现出一定的抑制作用。离体根尖的边缘细胞活性也随NaCl处理浓度与处理时间的增加而逐渐减小,但根边缘细胞黏胶层厚度却随NaCl处理浓度的增加而增加。总之,NaCl对黄瓜幼苗造成一定伤害,但根系边缘细胞可通过降解死亡与增加黏胶的分泌量在一定程度上减轻这种伤害程度。

The effects of NaCl on cucumber （Cucumis sativus） plant biomass, root length, root activity and the generation of the root border cells were investigated. The results showed that NaCl treatment led to decrease of plant biomass and root length and increase of root activity. The primal border cells occurred nearly synchro- nously with primary root tip growth in cucumber. The number and the viability of border cells reached maximum when root length extended to 25 mm. Both the number and activities of the border cells in vitro roots were gradually dropped while NaCl concentration increased and treatment time extended. In contrast, the mucilage thickness increased with elevation of NaCl concentration. In general, the root border cells could secrete mucilage and self-decompose under NaCl stress, which might protect root tip from NaCl toxicity in some degree.