Effects of traditional and new methods on overcoming lime-induced chlorosis of grapevine

Vitis vinifera L. cv. Merlot clone R3 grafted on the hybrid Vitis riparia x Vitis rupestris 3309C root-stock was grown in pots containing either calcareous or noncalcareous soil. Three treatments were applied to the plants growing on the calcareous soil: soil application of EDDHA (iron chelate), groundcover with Festuca ovina grass cv. Aurora Gold, and soil application of vivianite (iron phosphate). Shoot growth was recorded and at veraison the chlorosis occurrence and mineral element concentrations of young leaves were analyzed. Grape yield and berry composition were checked at harvest, including soluble solids, titratable acidity, tartaric acid, anthocyanins, polyphenols, and stilbenes. All treatments alleviated chlorosis symptoms over the untreated vines growing on calcareous soil. Grape yield and soluble solids were not affected by the treatments, while acidity, anthocyanins, and polyphenols evolved differently according to treatment. trans-Resveratrol concentration was reduced by all treatments. The floor management with Festuca ovina seems to be an effective, sustainable method to overcome lime-induced chlorosis, as compared with chelate and vivianite application