Reducing the amount of inorganic N fertilizers in superior grape vineyard by using organic and biofertilizers and humic acid [electronic resource].

Includes reference.

This study was carried out during three consecutive seasons of 2006, 2007 and 2008 on Superior grapevines to investigate the effect of inorganic, organic and biofertilization at different proportions and humic acid on some vegetative growth characters, vine nutritional status, berry setting %, yield shot berries % as well as some physical and chemical characters of the berries. The suitable N (80 gl vine) was applied either completely via inorganic form or in different proportions with organic and biofertilizers. Humic acid was added once at four levels namely 0.0, 1.0, 2.0 and 4.0 g ! vine. Results showed that using the suitable N as 50- 75 % inorganic and 12.5 to 25% organic and biofertilization caused a considerable stimulation on growth characters, leaf NPK, berry setting %, yield as well as physical and chemical characters of the berries as compared with using N via 100% inorganic. Using N as 25% inorganic and 37.5 of organic and biofertilization materially reduced growth characters, leaf NPK and caused a great decline on berry setting % and yield! vine rather than application of N as 100% inorganic or 50- 75% inorganic with different proportions with organic and biofertilizers. Physical and chemical quality of the berries % were obviously promoted with reducing inorganic % and increasing organic and biofertilizers %. There was a remarkable promotion on growth characters, leaf NPK , berry setting %, yield and fruit quality with increasing humic acid levels from 0.0 to 4 g / vine. It is advised to fertilize Superior grapevines with the suitable amount of N ( 80 g / vine) through 50% inorganic ( 40 g N equal 195 g ammonium sulphate! vine), 25% organic ( 20 g N equal 8.0 kg F.Y.M./ vine) and 25% bioform of N ( 20 g N equal 20 g Biogen/Vine) as well as application of 2 g humic acid! vine which were sufficient to maintain fair yield and quality of berries. Thus, it means the replacement of 50% of the chemical fertilizer with organic and biofertilization to produce healthy fruits that fitted for safe local consumption and fulfill the expanding exportation demand.

Summary in Arabic.

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