Effect of saline concentrations and humidity percentage on alfalfa va-rieties (Medicago sativa L.) from the Mexicali Valley, Mexico.

Objective: The aim of this experiment was to identify alfalfa varieties resistant to salt and drought stress in Mexicali Valley Mexico. Design/methodology/approach: Four alfalfa (M. sativa L.) varieties were used: Cuf-101 C, FD9, Pioneer and Cuf-101 P. Drought stress resistance was evaluated using four different percentages of commercial peat moss substrate (100%, 50%, 25%, and 15%), and saline stress resistance was evaluated by applying four concentrations of NaCl (0 mM, 50 mM, 100 mM, and 200 Mm.The variables evaluated in each treatment were: plant height, number of leaves and root length. The data obtained were subjected to an analysis of variance using the SAS statistical package version 9.0 with an α=0.5. Results: Alfalfa variety Cuf-101 had a good adaptation to both stresses with an average height of 11.28 cm and an average number of leaves of 3.54. Seed germination of alfalfa varieties (M. sativa L.) subjected to salt stress were affected even at the lowest NaCl concentration. Conclusions: The alfalfa variety with the highest germination percentage in all NaCl concentrations was Cuf-101 C with 91.17%.