Document Type : Original Article

Authors

1 Member of staff, Ferdowsi University of Mashhad, Iran

2 Ph.D. in Crop Physiology

3 PhD student of Agronomy, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran

Abstract

 Increased need for salinity tolerant plants continues due to increased use of saline water for irrigation in arid and semiarid regions. Kochia, a halophyte, which may be provided a good source of forage for livestock by using saline water. In order to investigate the salinity effect on some physiological characteristics of kochia, an experiment was conducted with supply of K+ and Ca+2 in green house and hydroponic condition. Two salinity levels including 20 dS m-1 and 40 dS m-1 and control (non saline water) and KCl (10mM), CaCl2 (10mM) and KCl with CaCl2 (5 mM) using split plot design, based on RCBD allocated in main and sub plot with six replications respectively. The results showed that increasing salinity significantly decreased spad value, F'v, F'v/F'm, photosynthetic pigments, total phenol, relative water content, membrane stability index , DPPH - radical scavenging activities and total dry matter production. Calcium applied enhanced rates of photosynthesis, chlorophyll a, chlorophyll b, MSI, DPPH - radical scavenging activities and potassium applied enhanced RWC in salinity stress. Application of calcium with potassium reduces the effect of salinity on F'o, F'm, F'v, F'v/F'm, total phenol and total dry matter production. Correlation coefficients showed significant correlation between dry matter production and all traits except photosynthesis, chlorophyll a to b ratio and DPPH - radical scavenging activities. Generally based on this it is appear that results application of K+ with Ca+2 alleviated effect of salinity and improved dry matter production of kochia.

Keywords