EFFECTS OF NACL AND ISO-OSMOTIC PEG STRESS ON THE GROWTH AND OSMOTIC COMPONENTS OF CUCUMBER SEEDLING

The effect of NaCl and iso-osmotic PEG stress on the growth and osmotic components in Jinchun No. 2 (Cucumis sativus L.) was investigated.
The results showed that both NaCl and iso-osmotic PEG stress significantly decreased dry weights of root, stem and leaf, as well as leaf area.
Plant growth was more affected by iso-osmotic PEG than NaCl treatment.
Both NaCl and iso-osmotic PEG stress significantly decreased leaf relative water content (RWC), but there was no significant difference in leaf RWC between NaCl and corresponding iso-osmotic PEG treatment.
The main change of osmotic components was the increase in Na+ and Cl- under NaCl stress, but the substances that obviously increased were proline and soluble sugar under iso-osmotic PEG stress.
Compared with the uptake of inorganic ions, plants should cost a higher energy to synthesize organic solutes for osmotic balance, which seems to result in a growth penalty.
Taken together, these results suggested that mainly an osmotic effect occurs in the short time NaCl stress.
In addition, the sensitivity was different between NaCl and iso-osmotic PEG treated plants, which could attribute to the different osmotic components under stress.

IV International Symposium on Cucurbits

Liang Chen, Yuan Huang, Ai Zhen, Zhilong Bie

cucumber, iso-osmotic stress, NaCl, PEG, osmotic adjustment

https://doi.org/10.17660/ActaHortic.2010.871.41