Selecting the optimum amount of organic, minral and biofertilizers responsible for maximizing the productivity of Balady guava trees

الملخص EN

The effect of supplying Balady guava trees with N at 400 g/tree from mineral source, filter mud and Bio Azotene in various percentages on leaf area, total chlorophylls, total carbohydrates, percentages of N, P, K and Mg, yield and fruit quality was studied during 2004 and 2005 seasons.

Nitrogen at the fixed rate namely 400 g/tree was applied either completely from mineral (ammonium sulphate), filter mud (2 % N) and Bio Azotene sources or in various proportions of each.

Results showed that combined application of N through mineral, filter mud and Bio Azzotene was effective in improving leaf area, total chlorophylls, total carbohydrates, percentages of N, P, K and Mg in the leaves, yield and fruit quality compared to using each source lower than 50% out of the recommended N.

Application of N completely via organic or biofertilizer form caused a reduction on the abovementioned traits compared to using N completely via mineral source.

Application of Bio Azotene alone was favourable than using filter mud in this connection.

Generally, fertilizing Balady guava trees with N at 400 g/tree in the form of 972 g ammonium sulphate + 5.0 kg filter mud + 12.5 g Bio Azotene/tree gava satisfactory promotion on yield and fruit quality