The Effect Of Urea Controlled By Nitrification Inhibitors For Apple Planting

The experiments were conducted in eight-year-old apple trees in Baishui station, belonging to NorthwestA&FUniversity. And the experiments had two factors, including the adding quantity of LSAP nitrification inhibitors and the applying content of nitrogen. By the determination of SPAD, length of new branches, total nitrogen, available nitrogen content of soil and fruit quality, the appropriate addition of LSAP was found. It provided a good idea for the reduction of nitrogen fertilization and guarantee of safety of fruit. The main results were as follows:1、When the adding radio was 2.73‰, the effect of nitrification inhibition was best, therefore, the change of ammonium nitrogen content had a minimum range; When the adding radio was 0.91‰, the effect of nitrification inhibition was lowest, therefore, the rate of ammonium nitrogen converting into nitrate nitrogen was the fastest;Compared with 2.73 ‰, when the adding ratio was 1.82 ‰,the effect of nitrification inhibition was little smaller.2、Adding nitrification inhibitors and did not reduce the amount of nitrogen, the length of shoot was the largest, the height of leaf was the heaviest, chlorophyll content and nitrogen content were the highest. It was beneficial for growth and development of apple trees; Adding nitrification inhibitors and the amount of nitrogen decreased by 10%- 10%, the growth and development status of apple trees were better than those dealing with fertilization of urea; Adding nitrification inhibitors and the amount of nitrogen decreased by 30%, the growth and development status were basically identical with those dealing with fertilization of urea.3、Adding nitrification inhibitors and did not reduce applying content of nitrogen, the weight of apple was the largest and the hardness was the highest; Adding nitrification inhibitors, with the decrease of the amount of nitrogen, the internal quality of apple decrease after increased first, and in the amount decreased by 20%, the sugar content and sugar-acid ratio were the highest.