Study On The Transportation Dynamic Of Nitrogen And Phosphorus In Soil-wheat System In Wheat-corn High Yield Ratation

In order to dicuss the transportation dynamic of nitrogen and phosphorus in the soil-wheat system, wedid experiment in Liu Zhai Village of Xunxian in Henan Province during2012-2013.The experimentchosen Zhoumai18and Jimai22as the experimental materials,it set up seven nitrogen treatments. One wasapplying none nitrogen during the whole stage which was expressed as N0, the others were nitrogentopdressing at jointing stage based on the basic nitrogen fertilizer120kg/ha, and the topdressing rate was0,60,100,140,180and210kg/ha, respectively, which was expressed as N1, N2, N3, N4, N5and N6.The articlestudied the transportation dynamic of nitrogen and phosphorus in the level of fertilizer,soil,cornstraw,wheat straw, the aim was to provide the theoretical basis of crop nitrogen and phosphorus nutrientresource efficient utilization.The main results were as follows:1.Nitrogen translocation in the soil-wheat system showed that it was not same that the change trend ofcomponents in the soil–wheat system each time. In over-wintering stage the loss of straw nitrogen wasless than the addition of soil nitrogen, the nitrogen of soil-wheat system was slightly reduced. Fromjointing stage to filling stage, plant nitrogen of Zhoumai18accumulated rapidly, soil nitrogen decreasedsignificantly, the loss of straw nitrogen was less, the total amount of nitrogen changes showed a trend ofrising. From jointing stage to anthesis stage, plant nitrogen of Jimai22accumulated rapidly, soil nitrogendecreased significantly, the total amount of nitrogen changes showed a trend of rising. Because the loss ofsoil nitrogen of Jimai22was more from anthesis to maturity, the amount of plant nitrogen was less, thetotal amount of nitrogen showed a trend of reducing.2.Phosphorus translocation in the soil-wheat system showed that the amount of the phosphorus in thesoil-wheat system showed a trend of decreasing, the treatment of N3、N4was lower than other treatments in phosphorus loss of Zhoumai18, the treatment of N1、N2was lower than other treatments in phosphorusloss of Jimai22. It was not same that the change trend of components in the soil–wheat system each time,the loss of straw phosphorus in over-wintering stage was less than the addition of phosphorus of the soil andplant.The jointing stage to mature the plant growed rapidly and the phosphorus of plant increasedrapidly,the phosphorus of soil decreased significantly, the loss of straw phosphorus was less, the loss ofstraw phosphorus and soil was greater than the phosphorus addition of the plant.3.The effects of nitrogen on winter wheat nitrogen accumulation and operation showed that thenitrogen accumulation and the contribution rate to grain of Zhoumai18were greater than Jimai22. Thenitrogen contribution rate of each vegetative organs to grain of Zhoumai18and Jimai22werecharacterized by leaf> stem sheath> glume and spike stalk.4.The effects of nitrogen on winter wheat phosphorus accumulation and operation showed that thephosphorus distribution of Zhoumai18was greater than Jimai22during mature period of wheat.Thephosphorus nutrition of each vegetative organs transfer rates of Zhoumai18and Jimai22werecharacterized by leaf> stem sheath,glume and spike stalk. The treatment of N3、N4was higher than othertreatments in the phosphorus contribution rate of each vegetative organs to grain of Zhoumai18. Thetreatment of N1、N2was higher than other treatments in the phosphorus contribution rate of each vegetativeorgans to grain of Jimai22.5.The accumulation of nitrogen and phosphorus directly affected the production of wheat. Thetreatment of N3、N4was higher than other treatments in nitrogen and phosphorus accumulation in floweringperiod, mature period of Zhoumai18. The treatment of N3was higher than other treatments in the wheatproduction of Zhoumai18. The treatment of N1、N2was higher than other treatments in nitrogen andphosphorus accumulation in flowering period, mature period of Jimai22. The treatment of N2was higher than other treatments in the wheat production of Jimai22. The highest production of Zhoumi18wasgreater than the highest production of Jimai22. The1000-kernel weight, grain weight and grain number ofZhoumai18were higher than Jimai22under the same nitrogen treatment.This study suggested that the topdressing nitrogen amount of140kg/ha or the total nitrogen amount of260kg/ha could increase the aborption and operation of nitrogen and phosphorus of Zhoumai18, andimprove the wheat production of Zhoumai18. While, the topdressing nitrogen amount of60kg/ha or thetotal nitrogen amount of180kg/ha could increase the absorption and operation of nitrogen and phosphorusof Jimai22, and improve the wheat production of Jimai22.