Effect of Phosphatic Fertilizer Rates Level on Growth, Crude Protein Content and Nitrogen Fixation Ability of Alfalfa at Sowing Year

Effect of Phosphatic Fertilizer Rates Level on Growth, Crude Protein Content and Nitrogen Fixation Ability of Alfalfa at Sowing Year

The experiment was conducted to determine effects of phosphate fertilizers on growth characteristics, crude protein content and nitrogen fixation ability of alfalfa (Medicago sativa L) in the sowing year. Two rates of phosphate (200 and 400 kg/ha P) were applied to phosphorus -deficient native soil in Korea and samples were taken every 7 days from the 30th to the 93rd day. Number of branches, root length and dry matter weight at phosphate fertilizer level of 400kg in sowing year more increased than those at 200kg/ha. The number of nodules did not differ due to phosphate fertilizer rate. The crude protein contents of leaves, stems and roots were not significantly affected by the phosphate fertilizer levels, except for those of leaves with 400kg/ha at 72 days after sowing that were higher. The crude protein contents of each plant along the growing stages were higher at the 44th and 72nd day after sowing. The dry weight of roots did not significantly respond to phosphate rates from 30 days to 51 days after sowing, but that was increased at phosphate fertilizer level of 400kg/ha from 51 days after sowing. The amount of ethylene evolved by samples during 2 hours and the calculated amount of nitrogen fixed were higher on phosphate fertilizer level of 400kg/ha from 30 days to 58 days after sowing, but decreased that.