Leaf nitrogen thresholds ensuring high antioxidant features of Vaccinium corymbosum cultivars

摘要: Deficiency or excess of nitrogen (N) supply can promote formation reactive oxygen species in plants, inducing oxidative stress. Otherwise, plants may enhance phenolics biosynthesis and antioxidant capacity under N deficiency, but this effect is plant species-dependent. There no information about influence on activity highbush blueberry (Vaccinium corymbosum L.), which quality commercial importance depend high concentration. We studied the variable (0 to 38 mM) uptake responses two cultivars (Legacy Bluegold) hydroponically grown at long-term. Nitrogen leaves concentration was enhanced for both increasing supply. Bluegold decreased CO2 assimilation 0 treatment, possibly due both, insufficient a decline superoxide dismutase (SOD) activity. In contrast, SOD activated Legacy N, interestingly only cultivar maintained rates across all treatments. Both showed higher levels 9 mM. Despite differential among cultivars, we propose threshold 15 g kg-1 DW ensure leaves.