The morpho-physiological responses of safflower to different types of tillage in rainfed conditions

Considering the importance of cultivating rainfed oil plants and the possibility of introducing them in rotation with wheat, in the present study, the reactions of the morpho-physiological traits of safflower (Carthamus tinctorius) in response to different types of tillage in rainfed conditions were evaluated. The experiment was conducted based on a randomized complete block design with three replications at Saral Rainfed Agricultural Research Station of Kurdistan during 2017-2019 seasons. The treatments were no-tillage, reduced tillage, and conventional tillage systems. The results of this experiment showed that the types of tillage caused changes in the morpho-physiological traits of the safflower. The highest yield (796 kg/ha) was obtained from no-tilllage system, which showed an increase of 24.8 and 40 percent compared to reduce tillage and no-tillage, respectively. In the no-tillage system, relative water content (69%), chlorophyll (2.01 mg/gr fresh weight of leaves) and leaf area index (2.8) were respectively higher than reduce tillage and conventional tillage. The highest amount of catalase and superoxide dismutase enzymes (0.085 and 0.72 units mg protein per minute, respectively) was observed in the leaves of plants cultivated by conventional system. In conventional tillage, the root colonization and sporulation were decreased significantly compared to the other two tillage systems. Finally, the physiological and biochemical traits related to yield in no-tillage and reduce tillage showed a more favorable and stable situation than conventional tillage.