Germination of Encholirium Spectabile Mart. Ex Schult. & Schult. F. Seeds in Response to Temperature and Water Stress

A study was conducted to examine the effects of different temperatures and water stress on Encholirium spectabile seeds.We evaluated the germination percentage, speed and time of germination of small (<2.97 mm), medium (2.97 ≤ M ≤ 4.01 mm) and large seeds (>4.01 mm), at temperatures of 15˚C, 20˚C, 25˚C, 30˚C, 35˚C, 40˚C and 45˚C and a photoperiod of 12 hours of light.Seeds were subjected to osmotic potentials of 0, -0.2, -0.4,-0.6, -0.8, -1.0, -1.2 and -1.4 MPa, induced by solutions of polyethylene glycol.The results indicated an excellent germination of medium and large seeds at the temperatures of 20˚C, 25˚C, 30˚C and 35˚C.The temperature of 35˚C provided the best mean germination time of large seeds and a higher speed rate of medium and large seeds.E. spectabile seeds germinate in a wide range of water deficit of -0.2 to -1.2 MPa.Germination reduced at concentrations of -1.0 and -1.2 MPa.No germination occurred at -1.4 MPa.Larger seeds showed the higher germination potential than medium and small seeds at the temperatures of 25˚C, 30˚C and 35˚C and in the range of water deficit of -0.2 to -1.2 Mpa.