EFFECT OF CALCIUM, LIME, WETTABLE SULFER AND COPPER OXICHLORIDE ON FRUIT QUALITY AND RESISTANCE TO FUNGUS DISEASES ON RUBY SEEDLESS GRAPEVINES

This trial was carried out during 2005 & 2006 on Ruby Seedless vines grown at EL-Khatatba region. The vines were sprayed with, lime and wettable sulfer (Wt.S), CaCl₂ with wettable sulfer, lime and CaCl₂ and wettable sulfer, lime and wettable sulfer and copper ox chloride (Cu), CaCl₂ and wettable sulfer and Cu, and lime and CaCl₂ and wettable sulfer and Cu. (One concentration to each compound was used at (3 g/L), application lime after two weeks of berry set, CaCl₂ after three weeks, wettable sulfer weekly from full bloom until fourth week after berry set, copper ox chloride after four weeks of berry set. All the trial vines were sprayed in long interval with wt.s (15 days) after bud burst). Lime or/and CaCl₂ with wt.s or/and copper oxicloride applications did not significantly increase cluster weight in the two seasons of study. Berry weight, berry size, berry firmness, SSC and sugar content of berries juice were significantly increased compared to the control. The best increments were noted with the applications lime and CaCl₂ and wt.s or and with copper ox chloride. On the other hand, acidity percentage of berries juice was significantly reduced compared to the control. Pruning wood weight and leaf area were not greatly affected in the first season, but were significantly increased in the second season as a result of lime, CaCl₂, wt.s or/and copper ox chloride applications.
Spur thickness was not significantly different in the two seasons of the study. All treatments recorded a satisfactory control of both powdery and downy mildew diseases. The best treatment was spraying the vines with lime followed by CaCl₂ and wettable sulfer with copper ox chloride which gave good fruit quality and controlled both powdery and downy mildew.