Yield and quality enhancement as influenced by pre-harvest nutrient spray in grapes (Vitis vinifera L.) var. Muscat Hamburg by adopting double pruning and double cropping system under Cumbum Valley condition

Abstract

An experiment was conducted to assess the effect of pre-harvest treatments on biometrical, physio-chemical and shelf life in grapes variety Muscat Hamburg. The experiment was conducted in randomized block design with 14 treatments (T1 (Ca(NO3­)2 0.5%), T2 (Ca(NO3)2 1.0%), T3 (KNO3 0.5%), T4 (KNO3 1.0%), T5 (CaCl2 0.5%), T6 (CaCl2 1.0%), T7 (sulphate of potash (SOP) 0.5%), T8 (SOP 1.0%), T9 (T1+T3), T10 (T2+T4), T11 (T5+T7), T12 (T6+T8), T13 (water spray) and T14 (control)) in two replications and imposed at berry development and veraison stage. The data revealed that T12 showed the highest values for bunch weight, fruit yield vine-1, berry diameter, berry weight, seed weight, berry firmness, juice recovery, TSS, total sugars, reducing sugars, non-reducing sugars, shelf life, petiole potassium and berry potassium with the least berry cracking, berry shattering, PLW and berry rotting. While T14 showed the lowest values for yield and quality parameters. The treatment T11 recorded the highest anthocyanin and total phenols content. T10 expressed the maximum nitrogen content in petiole, whereas T8 recorded the highest petiole phosphorus. The petiole calcium was more in T6. The highest petiole magnesium was found in T3.