This study was conducted at the farm of agriculture college (Abu Jarash),
Damascus university to determine the impact of time and depth of adding
phosphorus on it's availability in calcareous soil cultivated with corn during
2011 and 2012 seasons.
Super phosphorus fertilizer was added to the soil at
three different depths (0, 10 and 20 cm), while the control spot left without
fertilizer addition. Soil samples were taken for analysis of available phosphorus
(P) from 12 replicates at different depths 0-10, 10-20, 20-30, 30-40 cm with two
samples for every depth at zero time, 15, 30, 45, 60 and 90 days during the
growing corn.
Results indicated that the available phosphorus increased directly in all
samples after cultivation, with a marked value recorded at all depths after 15
days of cultivation. This concentration began decreasing gradually with a
constant rate in time in all transactions and reached 50% after 90 days of
cultivation. It was also observed that available phosphorus was higher at the
two depths, 0-10 and 10-20 cm and after 15 days of post- corn cultivation and
followed by zero time and it was found that the best concentration was
observed at depth extended from 0 to 20 cm in the treatment of adding
fertilizer at depth of 10 cm and time of sampling was 15 days of cultivation.
