Effects of calcium carbonate and phosphorus fertilizer on some physiological parameters and alizarin content of Rubia tinctorum L.

Madder (Rubia tinctorum L.) is a herbaceous and perennial plant, which has bioactive compounds with high medicinal and pigment potency. Local farmers believe that increasing soil lime increases the color composition of this plant. To investigate the effects of calcium carbonate and phosphorus fertilizer on some physiological parameters and root alizarin content in madder, a field factorial experiment was conducted in a randomized complete block design with four replications. Experimental treatments included calcium carbonate at five levels (0, 20, 50, 100, and 150 kg.ha-1) and triple superphosphate at four levels (0, 50, 100, and 150 kg.ha-1). Means comparison showed that the highest root dry weight (an increase of 75% compared to control), total plant dry weight (an increase of 58% compared to control), root alizarin content (an increase of 78% compared to control), and root catalase activity were obtained with calcium carbonate increase up to 20 kg.ha-1 and triple superphosphate increase up to 100 kg.ha-1. The highest root length (an increase of 54% compared to control) and leaf catalase activity were observed in the 50 kg.ha-1 calcium carbonate and 100 kg.ha-1 triple superphosphate treatment. The highest leaf and root peroxidase activity was obtained in the treatment of 150 kg.ha-1 calcium carbonate and 150 kg.ha-1 triple superphosphate. Simultaneous application of these two fertilizers had a complementary effect on each other, so that the 20 and 50 kg.ha-1 calcium carbonate application along with the 100 kg.ha-1 triple superphosphate had an increasing effect on the alizarin content of madder root. This method can be used for the future development of a non-destructive tolerance test that shows madder increased response to calcium carbonate and phosphorus fertilizer, to further produce madder root medicinal compounds as a targeted drug for cancer treatment.