Effect of biochar on growth characteristics and sodium to potassium ratio of summer savory (Satureja hortensis L.) under NaCl stress

Introduction Salt stress is one of the important reasons of different problems in agricultural productions. Also, because of competition between sodium (Na+) with essential cations that necessary for cellular function, salinity cause to limit in absorption of mineral contents and growth reduction. One way of exciting salt from soil profile is using organic amendments such as biochar that recently has been extremely considered as a result of the weather modifications and soil management. Due to the characteristics of organic matter biochar, in this research the effect of biochar on growth traits, sodium (Na+) and potassium (K+) concentration of summer savory leaf under salt stress resulting from irrigation with NaCl were investigated. Materials and methods In order to investigate the effect of biochar on growth characteristics, sodium (Na+) and potassium (K+) concentration of summer savory ( Satureja hortensis L.) leaf under NaCl stress, a pot experiment was performed as factorial based on completely randomized design with four replications in greenhouse condition at Horticultural Research Station, Ferdowsi University of Mashhad, Iran, in 2017. The factors of the test included three levels of biochar (0, 1 and 2 % w/w of soil of each pot) and irrigation with salty water in three levels of salinity (0, 40, 80 mM NaCl). In order to produce biochar, the woods of mulberry (Morus alba) three put in electrical furnace with 530 C temperature for 14 h. Then the biochar crushed in very small pieces, sieved and added to the soil. The growth parameters included height, number of branch let, stem diameter, number of nodule, stem fresh and dry weight, leaf fresh and dry weight were measured by common methods. The amount of Na+ and K+ from the leaf samples were also measured. Data analysis were done with Minitab 17 software. Results and discussion The results of analysis of variances showed that the interaction effects of salinity and biochar treatments on number of branch let, stem diameter, number of nodule, stem fresh and dry weight, leaf fresh weight, Na+ , K+ and K/Na ratio in P