Fig. 3

Effect of K+ deficiency on K concentration in cotton cultivars at the adequate and low K supply levels. a Leaf area. b chlorophyll content (SPAD value). Bars represent mean ± SD (n = 3 replicates). Statistical analysis was performed using two-way analysis of variance (ANOVA) and Tukey’s post hoc test. Different letters denote significant differences (P < 0.05)