Authors : Saeid Zehtab-Salmasi and Sajad Moghbeli
Abstract: This laboratory study evaluated how temperature and salinity affect seed germination. Silybum marianum seeds were subjected to incubation temperatures of 10, 15 and 20�C with varying levels of saline water during germination. The saline levels were 1, 3, 5, 7 and 9 deciSiemens per meter (dS m 1). Silybum marianum seeds also were tested using standard germination protocols, with the salt content of the wetting solution remaining constant. Germination was evaluated 6, 9, 12, 15, 18 and 21 days after placement in the incubators. Seeds incubated at 10�C did not germinate. At an incubation temperature of 15�C, less than optimal germination occurred during the 21 day test. After only 12 days, Silybum marianum seeds tested at 20�C came to within 90% of maximum germination. Salinity levels at or above 7 dS m 1 reduced germination by as much as 19% under 20�C conditions and by as much as 27% under 15�C conditions. Extrapolating these results to field conditions suggests that Silybum marianum should be planted into a seedbed with salinity less than 3 dS m 1 and an average temperature of 20�C for 12 days.
Saeid Zehtab-Salmasi and Sajad Moghbeli , 2008. Effects of Temperature and Salinity on Germination of Milk Thistle (Silybum marianum). Research Journal of Agronomy, 2: 31-35.