PEMBERIAN KOTORAN SAPI PADA PERTANAMAN JAGUNG (Zea mays): PERUBAHAN FRAKSI FOSFOR INORGANIK PADA ULTISOL GUNUNG SINDUR, JAWA BARAT

Experiment concerning the evaluation of the changes of inorganic phosphorus (P) fractions due to application of cow dung on corn cultivation was conducted in Cibadung village Gunung Sindur, West Java. The rates of cow dung were 0, 10, 20 and 40 tones ha -1 . Experiment was designed in completely randomized design with three replications. Soil samples collection were conducted after two weeks incubation and after harvesting. Soil samples were collected in rhizosphere and between rows of corn. The changes of inorganic P fractions were evaluated by the values which were obtained by subtracting the values of one P fraction after two weeks incubation from one P fraction after harvesting. The results showed that the application of cow dung significantly increased the resin-Pi fraction, NaHCO3-Pi fraction and NaOH-Pi fraction after two weeks incubation and after harvesting. The values of those P fractions in rhizosphere after harvesting were higher in general than those of between rows of corn. The changes of resin-Pi in rhizosphere and in between rows of corn were negatives values indicating that resinPi transformed to other fractions. The changes of NaHCO3-Pi and NaOH-Pi were inconsistently positives values in rhizosphere and in between rows of corn with the increasing rates of cow dung application. They indicated that plant uptake, P desorption and P transformation to more stable fractions affected the amount of NaHCO3-Pi and NaOH-Pi fractions.