Study on NPK absorption and accumulation in Zizvphus jujube tree

The yearly biomass, contents of nitrogen, phosphorus and potassium and their accumulation at different parts of Zizvphus jujube tree were studied. The trees are cultivated about 6 years under field condition. The results show that the cumulative amounts of dry matter, N, P and K in all organs are increased with the growth and development of Chinese jujube, especially from the fruit expanding stage to harvest stage. The yearly biomass increase is about 3908.5 g/plant. Total nitrogen, phosphorus and potassium absorption rates are 70.5, 19.9 and 99.3 g/plant in one year of the growing period , in which 55.6%、68.1% and 56.1% are absorbed during the harvest stage. To attain 1000 kg economic yield, Zizvphus jujube tree should uptake N 14.1, P 4.5 and K 19.9 kg.