Nitrogen release dynamics of PAL fertilizer and its effects on economic characters and yield of barley

A pot experiment was conducted to study the nitrogen release dynamics of a PAL fertilizer and its effects on economic characters and yield of barley.It was observed that there was no significant difference in NH~+_4-N release between PAL fertilizer and urea treatment.The trend of NO~-_3-N release was similarly "S" type curve,and there was a very significant difference.During the whole growth period of barley,there were two stages of nitrogen release from PAL fertilizer: the first stage was 0～14 d and the second stage was 28～42 d after applied.The function of nitrogen release from PAL fertilizer was satisfied with the nutrient demand of crop.Under the same nitrogen level,the yield of barley treated with PAL fertilizer was higher than that with urea.In the range of 0～7 kg/667m~2,as the nitrogen levels ascended,the yield of barley increased;in the range of 7～14 kg/667m~2,as the nitrogen levels ascended,the yield of barley descended.