Germination of Sorghum Seeds under Condition of Water Deficit

Seed germination of sorghum (Sorghum bicolor, variety Sucrosorgo 506) and maize (Zea mays, hybrid Kuxxar) was performed to determine the effect of different temperatures and water availability under controlled environment in 2010. Water stress was simulated by polyetylene glykol solutions (PEG 6000) corresponding to osmotic potential (Psi, MPa) of -0.05 MPa, -0.1 MPa and -0.5 MPa, respectively. The control variant was represented by distill water (Psi = 0 MPa). Germination was undertaken in climatic chambers (12 h light regime) at 10 and 20 degrees C. The aim of the study was to determine the ability of seeds to germinate under water deficit and set values of T-50. Seeds of S. bicolor showed higher germination under water stress conditions (Psi = -0.5 MPa, 20 degrees C) compared to Z. mays. The temperature of 10 C and Psi = -0.5 MPa did not favour germination in both species. The value T-50 in Z. mays at 20 degrees C was set to 1.9 days (0 MPa) and 8.9 (-0.5 MPa) and in S. bicolor 1.6 days (0 MPa) and 4.3 (-0.5 MPa), respectively.