Interaction of salinity and temperature on the germination of alfalfa cv CUF 101

Abstract

Alfalfa, Medicago sativa L is a major forage legume in the arid climate of the Gulf countries where salinity is a serious production problem. A laboratory experiment was initiated to evaluate the effect of salinity - temperature interactions on the germination of alfalfa cv CUF 101. The alfalfa seeds were sown in Petri dishes with saiine solutions of varying concentrations (electrical conductivities of 0.01, 6.4, 12.2, 17.4, 22.6, 27.2, 32.1 and 37.2 dSm-1) prepared with NaCl. The germination response of the seeds were determined over a wide range of temperatures (15, 20, 25, 30, 35 and 40 °C) for a period of 8 d. Germination counts, taken every 2 d, were used to compute germination rate index. Generally, germination percentage decreased with increasing salinity and was severely limited at 40 °C. Salinity-temperature interactions were highly significant. The optimum germination temperature was 20-25 °C. Based on these results, the most favourable period to establish alfalfa cv CUF 101 in the Sultanate of Oman and other areas with similar climatic conditions has been proposed. © 1993.