The effects of potassium and magnesium on yield and some physiological traits of Safflower (Carthamus tinctorius)

ABSTRACT: The objective of current study is to evaluate the effects of potassium and magnesium on yield and some physiological traits of Safflower (Carthamustinctorius). The experiment was conducted at University of MohagheghArdabili, Ardabil- Iran. The experimental design was factorial in complete randomized block design with three replications. The applied factors were consumption of potassium as potassium phosphate at three levels (0, 60, 120 kg p h) and magnesium as magnesium sulfate again at three levels (0, 75, 150 kg m h) , respectively. The result of experiment demonstrated that the consumption of potassium and magnesium stimulated the intake of both potassium and magnesium, hence P and M contents of Safflower increased. Potassium had positive effects on plants’ calcium contents. However, Magnesium had negative effects on calcium contents of Safflower. Moreover the increase of potassium level decreased sodium content and sodium absorption. The application of magnesium had significant effects on chlorophyll content of leaves. Whereas potassium increased relative moisture content of leaves, magnesium reduced moisture content. The consumption of both chemical fertilizers improved the stability of cytoplasm membrane. The highest capitol yield per plant was achieved from application of potassium and magnesium at 120 and 75 kg h levels, respectively. The highest number of seeds per capitol was achieved from 60 and 150 kg h of potassium and magnesium. The best combination of both fertilizers to achieve the highest 100 seeds weight was 60 kg p h and 75 to 150 kg m h. the highest and the lowest 100 seeds weight were gained from 120 kg p h and lack of potassium treatments which was identical for the magnesium. Potassium and magnesium both had significant and non-significant impacts on seed oil content. The highest seed oil content was achieved from 120 kg p h and 60 kg m h. on the contrary the lowest seed oil content was achieved from lack of magnesium.