The Potential Role of Osmotic Pressure to Exogenous Application of Phytohormones on Crop Plants Grown under Different Osmotic Stress

Hamdia M Abd El-Samad

doi:10.4236/ajps.2016.76089

Abstract

The osmotic pressure represented as a sign of plant tolerance or sensitive to salinity stress. In the following plants, the increase in OP seems to be a manner of defense mechanism to survive. OP increased in shoots of maize, shoot and root of wheat and cotton plants was concomitant with shoot soluble sugar, root soluble protein and shoot and root amino acids of maize plants. However, in wheat the increase in OP was related with increase of root soluble sugar and protein of shoots and roots. In cotton plants, the elevation of OP was run parallel with increase soluble sugar of shoots and roots, shoot soluble protein and root amino acids. The increase in OP was related with a marked and significant reduction in the water content of these plants. However, the decrease in OP of shoot and root of broad bean was related with the reduction of shoots and roots soluble sugar, protein and root amino acids of broad bean. While the OP becomes more or less unchanged in shoots and tended to decrease in root of parsley plants, this concomitant with unchanged trend in the shoots amino acids and reduction in root soluble sugar and root amino acids. Run with previous trend values of OP and metabolites of parsley plants were related with stable values in shoot water content and reduction in root water content. With GA3 and kinetin treatments mostly increase the values OP which parallel with increase and soluble sugar, soluble protein and amino acids contents of shoots and roots of maize, wheat, cotton, broad bean and parsley plants with NaCl increasing. This related with increase water uptake by roots in these plants. The results indicated that kinetin had a more effective to shoot maize, both organs of wheat, broad bean and parsley plants in response to salinity stress while GA3 was more effective on cotton plants especially at higher levels of salinity. Thus plants strategy differed in their tolerance to salinity stress according to their species and differed also according to the different organs of the same plants and kinetin treatment induced highly positively affect than GA3 treatments.

Highlights

Several environmental factors adversely affect plant growth development, hindering and seed germination such as water deficit, freezing, heat and salt stress
OP increased in shoots of maize, shoot and root of wheat and cotton plants was concomitant with shoot soluble sugar, root soluble protein and shoot and root amino acids of maize plants
The results obtained here indicated that kinetin has a more effective to shoot maize, both organs of wheat, broad bean and parsley plants in response to salinity stress while GA3 was more effective on cotton plants especially at higher levels of salinity [37]

Summary

Introduction

Several environmental factors adversely affect plant growth development, hindering and seed germination such as water deficit, freezing, heat and salt stress. There have been numerous studies of the effects of salinity on plants [9]. Some researchers have used exogenous application of biofertlizers as PGRs for reducing or eradicating the saline injury in plants [11]. It is thought that the repressive effect of salinity on seed germination and plant growth could be related to a lowering of endogenous concentrations of plant growth hormones [13]. The exogenous application of PGRs, auxins [15], gibberellins [16], cytokinins [17] produces improves plant seed germination, growth, development and seed yields and yield quality under salinity stress [18]-[22]

Methods

Results

Discussion

Conclusion