Absorption And Distribution Of Nitrogen Treatment And Its Effect On Yield And Quality In Zhonghuashoutao Peach

Nitrogen was a key factor for furit yield and qulity. Based on the requirement of high quality fruit, it was important to rationalize nitrogen application.The experiment using the stable isotope ¹⁵N-labelled was carried out from 2009 to 2010. The characteristics of ¹⁵N absorption, distribution and utilization at different growth stages when fertilize in defferent phases and method, and the effect of different nitrogen treatment on yield and quality under the condition of field cultivation by using thirteen-year-old peach (prunus persica l. CV) were studied. The main results were as follows:1,A field experiment was carried out to evaluate the effects of different fertilizer amount (compost N:P:K=16:8:20,0-2250kg/ha)on yield, quality and soil mineral nitrogen. The result showed that all the treatments increased inorganic nitrogen accumulation in soil and chlorophyll content. On balance, the treatment of 1500kg/ha showed optimal performance increased the growth of individual fruit by 20.8%, yield by 26.4%, soluble solid by 1% vs. controls.Using ¹⁵N tracer technique to evaluate the characteristics of ¹⁵N absorption, distribution when fertilize before fruit expanding stage.Two weeks after suppling nitrogen, ¹⁵N was found in leaf, and the ¹⁵N content increased as the time. The ¹⁵N content of fruit and leaf was similar at the stage of fruit expanding. However leaf and fruit took up NH4-¹⁵N faster when NH4-¹⁵N andNO3-¹⁵N supplied simultaneously.In the following year, the Ndff% of leaf and fruit was observably higher in the treatment of fertilize before fruit expanding stage than in sping before sprout. In conclusion, rational fertilizer befor fruit expanding could increase yield and quality, and also was good for flowering,fruit setting and growth.2,At the stage of harvest, we parsed the whole plant that was fertilized in defferent phases(before fruit expanding,before sprout and in neonatal branch rapid growth period) . We found that the largest amount of ¹⁵N in new-growth organs (leaves , branches and fruit) was in the treatment of fruit expanding stage; N distribution rate in perennial branches and roots was about40-56%, in leaf and new-growth branches was 35%,and in fruit was 6-20%. In the treatment of in summer the largest amount of ¹⁵N was detected in the perennial branch and roots, lower distribution rate in fruit. Nitrogen use efficiency of treatments was significantly different, which were 21.00% (before expanding stage), 16.12% (before sprout), and 17.96% (summer) in the harvest period.3,The method of fertilizer had significantly effect on the absorption, distribution of nitrogen. Radial ditch fertilizing before sprout was very helpful to increase N distribution in leaf and new-growth branch, the distribution rate was 44.8%. However annularity ditch fertilization treatment was only 38.44%. When fertilize in summer, ¹⁵N increased the partitioning to perennial branches and roots. Radial ditch fertilizing and annularity ditch fertilization resulted in the similarly N partitioning into the strage organs. Radial ditch fertilizing was 55.14% and annularity ditch fertilization was 57.05%. Reproductive organ of different treatments had low distribution rate, Radial ditch fertilizing was 6.58% and annularity ditch fertilization was 8.27%. Nitrogen use efficiency of annularity ditch treatments was higher than radial ditch treatment.4,¹⁵N -urea daubed on the branches of zhonghuashoutao before sprout, the branch had the ability of absorbing ¹⁵N. ¹⁵N transport and distribution in the new organs was controlled by the growth center after sprout. ¹⁵N -urea daubed on the branches before sprout was very helpful to increase N distribution in new growth organ, in full blossom ¹⁵N was found in flower, and the Ndff% was 2.39 times of fertilizeing before fruit expanding stage. N-urea sprayed before sprout, compared with control (water spraying), the content of chlorophyll in peach leaf improved markedly and the function of leaf had been enhanced, setting percentage and volume of fruit increased, finallay the weight of simple fruit was improved.