Effect of phosphorus and potassium fertilization on growth of burdock plant ( Arctium lappa L.) and its roots content of total phenols

Abstract

A field experiment was carried out in the Experimental Researches Station (2) , Agriculture College - Al-Muthanna University , during 2017-2018 to study the effect of three levels of phosphorus (0, 80 and 120 kg P2O5.ha-1) and three levels of potassium (0, 100 and 150 kg K2O.ha-1) on growth of burdock plant( Arctium lappa L.) and its roots content of total phenols . Randomized Complete Block Design was used with three replicates. Results showed the plants significantly supervised treated at the level (120 Kg P2O5.ha-1) in plant height (50.77 cm) , number of leaves (10.23 leaf) , leaf area (75.43 dm2) , shoot dry weight (64.6 g ) , root dry weight (79.18 g) and roots content of total phenols (40.57 mg GAE. g-1dw). Potassium fertilization at level (150 kg K2O.ha-1) significantly supervised in plant height , number of leaves, leaf area , shoot dry weight , root dry weight (52.66 cm , 10.68 leaf , 75.43 dm2 , 65.7 g and 82.21g) respectively. While, the plants that treated at the level (100 Kg K2O.ha-1) gave highest content of total phenols in roots (44.41 mg GAE. g-1dw).