Morphophysiological and biochemical response of savory medicinal plant using silicon under salt stress

Hamid Mohammadi,Saeid Hazrati,Laleh Parviz

doi:10.17951/c.2017.72.2.29-40

Abstract

<p>Salt stress is one of the most important factors limiting the growth and yield of plants around the world. However, silicon can reduce the harmful effects of salt stress on plants. For this purpose, an experiment was conducted in a factorial arrangement on randomized complete block design with three replications in a research greenhouse on the Satureja hortensis medicinal plant. Experimental treatments consisted of two salinity levels (control and 100 mM) and potassium silicate (Si) at three levels (0, 1, and 2 mM). The results showed that salinity reduced shoot dry weight, photosynthetic pigments and potassium content of shoot. However, sodium, proline, MDA, and H2O2 contents in shoot increased. The highest shoot dry weight, photosynthetic pigment content, proline, RWC, and the lowest content of MDA and H2O2 of the shoot were observed with Si application under salt stress and non-salt stress conditions. The highest yield of essential oil was also observed with Si application under salt stress and non-salt stress conditions. Therefore, the use of silicon in salt stress condition not only minimizes the harmful effects of salt stress by increasing the K+/Na+ ratio and improving the morphological and physiological traits of the Satureja hortensis medicinal plant but also improves the essential oil yield of this medicinal plant in salt stress and non-salt stress conditions.</p>

Highlights

Salinity is one of the environmental factors limiting crop and medicinal plants yield in arid and semi-arid regions that disrupt the natural growth and development of plants in vast areas of the earth’s surface [46]
Studies show that the main components that regulate salinity tolerance include reduced salt uptake or salt exclusion, increased potassium ion/ sodium ion ratio, tissue tolerance, stomatal closure, up-regulation of antioxidant system to protect against reactive oxygen species (ROS), osmolyte synthesis, high water use eficiency, early lowering and further growth to dilute the concentration of salt in plant tissues [14, 31]
In order to evaluate whether Si application favours morphological, physiological traits and essential oils yield in the savory plant Satureja hortensis, the effects of Si application and salinity stress were carried out as a factorial experiment based on randomized complete block design with

Summary

INTRODUCTION

Salinity is one of the environmental factors limiting crop and medicinal plants yield in arid and semi-arid regions that disrupt the natural growth and development of plants in vast areas of the earth’s surface [46]. Studies show that the main components that regulate salinity tolerance include reduced salt uptake or salt exclusion, increased potassium ion/ sodium ion ratio, tissue tolerance, stomatal closure, up-regulation of antioxidant system to protect against ROS, osmolyte synthesis, high water use eficiency, early lowering and further growth to dilute the concentration of salt in plant tissues [14, 31]. Studies have shown that the application of Si in plants under salt stress reduces the harmful effects of stress, including reducing sodium and chlorine uptake [53], increasing mineral absorption [28], solute biosynthesis [61], and improving the antioxidant system of the plant [59]. The main goals of this study were to evaluate the inluences of Si application on some morphological, physiological characteristics and essential oil yield in summer savory plant under salinity stress conditions

MATERIALS AND METhODS

StatiStical analySiS

Shoot dry df matter

Essential oil yield

Findings

CONCLUSION