Effect of inland salt-affected soil on physiological and growth characters of Eucalypt tree (Eucalyptus camaldulensis Dehnh.)

Abstract

Eucalyptus tree is a high potential plant species as a deep root system for water absorption to prevent the salt rise-up, a large bushy to cover the surface area and to detoxify the toxic salt ions. The aim of this research is to investigate the responses of Eucalyptus camaldulensis to different sites of inland salinity. Survival percentage of salt-stressed eucalypt was decreased, relating to salt contamination and negatively correlated with proline accumulation. Water use efficiency in the salt-stressed leaves was negatively related to electro conductivity (EC) values in the salt-affected soil. Chlorophyll a (Chla) and total chlorophyll (TC) degradations were positively related to maximum quantum yield of photosystem II (PSII) (Fv/Fm) (r2=0.89) and quantum efficiency of PSII (FPSII) (r2=0.95), leading to low net photosynthetic rate (Pn) (r2=0.79) and to reduce the growth characteristics in term of plant height and circumstance. The survived eucalypt plants in the severe salinity land containing high salt contamination (1.7-2.0% salt) may be further applied as potential plant species to remediate the inland salinity soil.