Effect of salt stress on morpho-physiological and anatomical attributes of Salix clones

Abstract

The aim of the study was to assess and quantify the impact of salt stress on key morpho-physiological traits that influence biomass production in Salix clones. In February 2021, a pot experiment was conducted using stem cuttings of five selected Salix clones. The experiment followed a Factorial Completely Randomized Design (CRD) with four replications. The clones were subjected to different levels of NaCl treatments (0, 20, 40, 60, and 80 mM) during the active growth period. The observations on growth and physiological characteristics of clones were recorded at an interval of two months after initiation of salinity treatments i.e., May, July and October. However, the biomass parameters were recorded at the end of experiment. All the growth and biomass traits showed significant reduction with increase in salinity treatments. Among physiological traits significant reduction were observed in total chlorophyll, carotenoids and relative water content, while salinity stress raised the content of proline, total soluble sugar, total soluble protein and Na+/K+ ratio in all the clones. The enzymatic activities of POD and SOD increased in all the clones when subjected to higher levels of salinity stress. On the basis of overall mean performance, clone UHF-03 showed optimum growth and biomass accumulation at 80 mM and was found to be the most tolerant to salinity stress. SEM and EDS mapping confirmed anatomical changes and Na accumulations in the roots and leaves of Salix in response to salinity stress.