Reduced levels of calcium and other mineral elements in grapevine leaves affected by Bois noir (BN)

Abstract

The concentrations of seven mineral elements (Ca, K, N, Mg, Mn, Fe and P) were analyzed in leaves of healthy gra- pevines and of grapevines infected with Bois noir (BN). The levels of calcium of all five varieties used in the study(\u27Chardonnay\u27, \u27MuÈller Thurgau\u27, \u27Pinot Noir\u27, \u27Lagrein\u27 and \u27Zweigelt\u27) were significantly lower in leaves infected with BN. The other six elements also showed a tendency towards decreased contents, but the effects were less consi-stent. A distinctive varietal influence on both visual symptoms of BN and mineral contents was observed, \u27Chardon-nay\u27 and \u27Zweigelt\u27 being the most susceptible cultivars