EFFECT OF PHOSPHORUS FERTILIZER ON THE YIELD AND QUALITY OF MAIZE (Zea mays L) FODDER ON CLAY LOAM SOIL
M. Rashid and M. Iqbal
Directorate of Livestock Production Research Institute Bahadurnagar Okara.
Corresponding author e-mail: mruaf@yahoo.com
ABSTRACT
Maize is an important Kharief (summer) fodder for animals in Pakistan. Phosphorus is a quality nutrient for fodders. The use of P for maize fodder is negligible. Thus a field study was conducted to evaluate the effect of Phosphorus fertilizer on the yield and quality of maize fodder on a clay loam (calcareous) soil. Adsorption isotherm was constructed by equilibrating 2.5 g soil with 25 ml of 0.01 M CaCl2 solution containing 0, 20, 40, 60, 80, 100, 200,300,400 and 500 µg P mL-1 as KH2PO4 and shaking for 24 hour at 20 0C. Phosphorus fertilizer doses were computed by using empirically derived Freundlich equation to adjust soil solution Phosphorus levels of 0.05, 0.1, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and 0.50 mg P L-1. It was observed that different Phosphorus fertilizer doses were required to adjust different soil solution Phosphorus levels. Adsorption of Phosphorus increased with phosphorus application rate but marginal adsorption decreased significantly. Yield and quality of maize fodder were improved with Phosphorus application. Yield increased upto T8 where Phosphorus was applied @ 53 kg ha-1 but quality traits (P concentration, dry matter, crude protein, crude fiber and ash contents (%) improved with the highest rate of Phosphorus use i.e. 57 kg ha-1. Phosphorus application showed non-significant affect on NDF and ADF contents (%). External and internal Phosphorus requirements of maize fodder to obtain 95 % relative yield were 0.25 mg L-1 and 0.23 mg L-1 respectively.
Key word: - P fertilization, derived Freundlich equation, maize fodder yield and quality. |