Determination of the physiological and biochemical effects of humic acid application in strawberry plant grown under salt stress

Abstract

The reduction of salt toxicity in the soil environment significantly contributes to the growth and development of plants. In this study, tolerance and development status of strawberry plant were investigated through irrigation solution including 50 mmol L-1 NaCl salinity and the application of 50 mg L-1 humic acid (HA). The physiological and biochemical parameters in vegetative and fruit stages and the mineral contents of strawberry plants were assessed if application of HA contributed to salt tolerance mechanisms of strawberry plants. HA improved physiological parameters such as crown and root fresh weight, crown and root dry weight, stomatal conductance as well as improving biochemical parameters and reducing stress metabolites such as (total chlorophyll contents, proline, malondialdehyde, catalase, and peroxidase enzyme activities). HA application (50 mg L-1) under salt stress (50 mmol L-1) also improved the quality parameters such as vitamin C and lycopene contents. We suggest that HA application is beneficial via increasing the tolerance mechanisms of salt-sensitive strawberry plants.