increasing tolerance to salt-dryness stress of snail medic seedlings using magnetic field and ultrasonic waves

Snail medic (medicago scutellata l.) is among the crucial medicinal legumes that exhibit minimal growth rates during the germination stage under salt and drought stresses. the objective of this study is to identify the sensitive components of seedling growth in response to salt and drought stresses. in the first experiment, seeds were subjected to magnetic field levels of 125 and 250 mt for varying durations (6, 12, 18, and 24 h). in the second experiment, ultrasonic waves were applied for durations of 3, 6, 9, 12, and 15 min. both experiments were conducted using various osmotic pressures (op) induced by nacl (-3, -6, -9, and -12 mpa) and peg 6000 (for similar ops) with three replications. the results indicated that seedling growth rate (sgr), weight of mobilized seed reserve (wmsr), seed reserve depletion (srdp), and seed reserve utilization efficiency (srue) were significantly affected by salt and drought stresses. moreover, the maximum seedling dry weight (sldw) of 0.195 mg was observed in the magnetic field treatments of 125 mt during 12 h, and the srue of 0.665 mg seed-1 was attained in ultrasonic wave treatments of 6 and 9 min. under drought stress conditions, the maximum root length (22.84 mm), shoot length (8.09 mm), seed germination (49.93%), wmsr (0.096 mg per seed), and srdp (43.1%) were obtained with the ultrasonic treatment of 9 min. furthermore, the maximum sldw of 0.09 mg was observed in the magnetic field treatment of 250 mt, and the maximum srue (0.516 mg seed-1) was obtained in the control treatment. for the improvement of salt and drought tolerances, priming with magnetic field and ultrasonic waves at 125 and 250 mt for 12 h and 9 min, respectively, can be efficiently used as pre-sowing treatments for snail medic seeds.