| Abstract: | ABSTRACT A greenhouse experiment was performed to evaluate macronutrients and boron deficiencies on vitexin bioproduction by sweet passion fruit leaves. Sand irrigated with nutrient solution was used as substrate in a complete randomized design, with eight treatments: 1) complete, 2) nitrogen-deficient(-N), 3) phosphorus-deficient(-P), 4) potassium-deficient(-K), 5) calcium-deficient(-Ca), 6) magnesium-deficient(-Mg), 7) sulfur-deficient(-S), and 8) boron-deficient(-B). After thirty days, the fourth fully expanded leaves were harvested. Under deficiency treatments, leaf dry matter concentrations of N, P, K, Ca, Mg, S, and B were 52, 53, 62, 76, 69, 31, and 80% lower than in complete treatment, respectively. Nitrogen, P, and K deficiency increased vitexin leaf concentration by 46, 16, and 18%, although Ca and B deficiencies decreased vitexin concentration by 22 and 33%, respectively, when compared to complete treatment. Magnesium and S deficiencies had no significant effect on vitexin concentration. In complete treatment, the concentration of nutrients and vitexin, in leaf dry matter were: 43.4 g kg? 1 of N, 2.47 g kg? 1 of P, 27.4 g kg? 1 of K, 15.6 g kg? 1 of Ca, 3.8 g kg? 1 of Mg, 5.28 g kg? 1 of S, 64 mg kg? 1 of B, and 5.57 mg kg? 1 of vitexin. |
