Fig. 13
Effect of N-forms (at 5 mM) and dissolved O2 levels (1.8 ± 0.2; 2.6 ± 0.2; 3.8 ± 0.2; 5.3 ± 0.2 mg. L− 1) of nutrient solution on maximal quantum yield of PSII photochemistry (Fv/Fm) of bell pepper plants. Different letters show significant different, Duncan’s test (p ≤ 0.01)