Fig. 2

Effect of caffeic acid (CA), cobalt sulfate (CoSO4), and nanoparticle coated urea (NPCU) on chlorophyll a (A), chlorophyll b (B), total chlorophyll (C) and carotenoid (D) concentration of leaves of potatoes. The Tukey test measured significant differences (p ≤ 0.05); distinct letters on the bars are the mean of four replicates ± SE.