## 3 Results  
### Physiological Characteristics, Seed Yield and Yield Components  
The effects of drought stress on all analysed traits were significant (Table 3). The values of physiological and agronomic traits differed significantly between the winter thistle genotypes. The interaction effects between drought stress and genotype were also significant for all traits, except for the water stress index, osmotic adjustment and agronomic water use efficiency (Table 3).  
genotypes, Parnian with the higher CWSI value, had lower values in physiological and agronomic traits under all water conditions, except for 1000-seed weight (Table 4).  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Stress Levels** & **Genotype** & **Crop Water** & **Relative Water** & **Stomatal** & **Osmotic** & **Water Potential** \\  & **Stress Index** & **Content** & **Conductance** & **Adjustment** & **(MPa)** & **(MPa)** \\ \hline Non-stressed & Padideh & 0.353 d & 0.76 a & 0.738 a & 1.508 bc & \(-\)0.24 bc \\  & Golemehr & 0.338 d & 0.72 b & 0.622 c & 1.633 a & \(-\)0.21 a \\  & Mec.14 & 0.322 d & 0.76 a & 0.695 b & 1.592 ab & \(-\)0.21 a \\  & Mec.248 & 0.357 d & 0.75 a & 0.662 b & 1.525 bc & \(-\)0.23 ab \\  & Mec.295 & 0.330 d & 0.74 a & 0.682 b & 1.658 a & \(-\)0.20 a \\  & Parnian & 0.448 c & 0.72 b & 0.627 c & 1.450 c & \(-\)0.26 c \\ Stressed & Padideh & 0.632 b & 0.66 c & 0.553 d & 0.642 f & \(-\)0.72 g \\  & Golemehr & 0.615 b & 0.56 d & 0.497 ef & 0.783 de & \(-\)0.63 e \\  & Mec.14 & 0.613 b & 0.64 c & 0.553 d & 0.750 de & \(-\)0.64 ef \\  & Mec.248 & 0.625 b & 0.65 c & 0.547 d & 0.716 ef & \(-\)0.66 f \\  & Mec.295 & 0.603 b & 0.64 c & 0.530 de & 0.850 d & \(-\)0.59 d \\  & Parnian & 0.713 a & 0.56 d & 0.480 f & 0.642 f & \(-\)0.815 h \\ \hline LSD 5\% & & 0.0466 & 0.0203 & 0.0338 & 0.0987 & 0.0279 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Mean values of traits measured on safflower genotypes at different stress levels 2017–2019.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & & & **Mean Squares** & & \\ \hline
**Source** & **df** & **Crop Water** & **Relative** & **Stomatal** & **Osmotic** & **Water** \\  & **Stress Index** & **Water Content** & **Conductance** & **Adjustment** & **Potential** \\ \hline Year (Y) & 1 & 0.001 & 0.0009 & 0.0008 & 0.009 & 0.0009 \\ Replication/Y & 4 & 0.001 & 0.0010 & 0.0010 & 0.002 & 0.0009 \\ Stress (S) & 1 & 1.376 ** & 0.2780 ** & 0.3740 ** & 12.417 ** & 3.6990 ** \\ S \(\times\) Y & 1 & 0.001 & 0.0009 & 0.0010 & 0.009 & 0.0007 \\ Error1 & 4 & 0.001 & 0.0003 & 0.0008 & 0.003 & 0.0009 \\ Genotype (G) & 5 & 0.022 ** & 0.0120 ** & 0.0160 ** & 0.077 ** & 0.0310 ** \\ G \(\times\) Y & 5 & 0.001 & 0.0007 & 0.0007 & 0.002 & 0.0003 \\ S \(\times\) G & 5 & 0.001 & 0.0020 ** & 0.0020 ** & 0.003 & 0.0110 ** \\ S \(\times\)G x Y & 5 & 0.001 & 0.00009 & 0.0010 & 0.002 & 0.0004 \\ Error2 & 40 & 0.001 & 0.0005 & 0.0005 & 0.004 & 0.0003 \\ \hline C.V (\%) & & 4.28 & 2.12 & 3.26 & 5.74 & 3.96 \\ \hline \hline \multirow{2}{*}{**Source**} & **df** & **Water Use** & **Capitula per** & **Seeds in a** & **1000-Seed** & **Seed Yield** \\  & **efficiency** & **Plant** & **Capitulum** & **Weight** & **Seed Yield** \\ \hline Year (Y) & 1 & 0.0003 & 0.500 & 3.920 & 0.245 & 8320.500 \\ Replication/Y & 4 & 0.0010 & 1.778 & 10.891 & 12.757 & 185,288.153 \\ Stress (S) & 1 & 0.1670 ** & 53.389 ** & 1226.776 ** & 64.980 * & 17,586,406.55 ** \\ S \(\times\) Y & 1 & 0.0004 & 2.000 & 0.376 & 7.736 & 590