Evaluating Alfalfa (Medicago sativa L.) Cultivars for Salt Tolerance Using Laboratory, Greenhouse and Field Methods

Abstract

Salinity is a limiting factor in irrigated alfalfa (Medicago sativa L.) production in many regions of the world. Objectives of this project were to evaluate twelve alfalfa cultivar responsesto salinity using laboratory, greenhouse and field experiments. The laboratory experiment evaluated plant germination under increasing levels of salt concentration (0 to 2%) and statistical differences were observed at 1.0%, 1.5% and 2.0% concentrations (10 000 ppm to 20 000 ppm). The greenhouse experiment evaluated forage production of cultivars using Salt Control Ratio (SCR) values using 3840 ppm irrigation water and significant differences were found between cultivars. The field experiment evaluated forage production under saline field conditions west of Pecos, TX (soil salinity 2131 ppm, water salinity 2950 ppm) with significant differences between cultivar yields.Canonical Correspondence Analysis (CCA), a constrained ordination technique,revealed statistical significance of canonical axes in explaining variation between alfalfa cultivars and laboratory, greenhouse and field experiments.