Effect of Some Sources of Organic Fertilizers on Grape Nutrition, Yield and Fruit Quality of Flame Seedless Grapevines

Abstract

This study was carried out during 2003, 2004 and 2005 seasons to study the effect of some sources of organic fertilizers on yield, fruit quality and the residues of the nitrate and nitrite in berry juice of Flame Seedless grapevines growing in a clay soil under drip irrigation system in a private vineyard located at Dakahlia governorate.Three organic manures (cattle, chicken or town manure) as a sources of organic N were examined at 40 N units/vine either alone or combined with N mineral fertilizer at the rate of 10 N/unit organic manure plus 30 N/units mineral fertilizer compared with the control (60 N/unit).The results obtained in this investigation indicated that organic manures combined with the mineral N fertilizer significantly increased leaf area percentage, N, P and K in the leaves as compared with the mineral N fertilizer (control) or organic fertilizers alone. The best treatments were obtained from vines receiving chicken manure. Cattle manure however caused the lowest values of leaf area. Moreover, organic manures combined with mineral N fertilizers significantly increased yield, bunch weight and volume berry weight and volume and juice as well as TSS, TSS/acidity and total anthocyanin in the skin of berries decreased acidity in the juice. Also, organic manure treatments significantly decreased the residues of nitrate and nitrite in the juice of berries. Chicken manure as a local organic manure which is available in a low price was considered the best organic fertilizer with a good source of N, P and K improve yield, berry quality and reduce the residues of nitrate and nitrite in berry juice decreased environmental pollution. Data also indicates that, although the productivity of the vines fertilized with nitrogen mineral fertilizers and organic mineral fertilizer give the highest productivity as compared with organic fertilizers , except for the chicken manure with achieved the highest economic return due to the net increase due to the high prices given for the production of the crop organically fertilized only.