Effects Of Nitrogen Regulation On Wheat Population, Dry Matter And Plant Nitrogen Accumulation

Effect of nitrogen regulation on wheat yield,population dynamic,dry matter accumulation, nitrogen uptake were counducted with Yumai49-198astested varieties, with three planting density sowing quantity with7.5kg/mu,10kg/mu,12.5kg/mu, three nitrogen regulation periods and three concentration through fieldexperiment,the main result was as follows:1． Density was the main factor of wheat population quantity.There exist significantdifference among different period and density, Showed that the high densitytreatment was higher than the medium density treatment; the medium densitytreatment was higher than that of low density.It could slow down the decreaserate of wheat population with2%concentration nitrogen regulation in jointingstage.2． From Wintering period to The harvest period dry matter accumulation amountwas increased in the extension of wheat growth period.The dry matteraccumulation reached maximum in wheat harvest period. Density was the mainfactor of dry matter accumulation of wheat, with higher density, dry matter more.Dry matter accumulation accounts was accounted for70%after jointing stageand2%nitrogen concentration regulation in jointing stage could increase drymatter accumulation in wheat.3． The nitrogen Accumulation of wheat from Returning to harvest continued toincrease, probably accounted for around60%in the jointing stage.The amount ofnitrogen uptake of Low density of wheat grain and total nitrogen uptake wassignificantly lower than that in moderate and high density, the ratio of amount ofnitrogen uptake and total nitrogen uptake of Low density of wheat wassignificantly higher than medium density and high density of wheat and themedium density of wheat was higher than that of high density of Wheat.lowdensity2%and6%concentration could increase the wheat nitrogenaccumulation and the nitrogen content of grain in the regulation of nitrogen atjointing stage. Medium density and high density2%and6%nitrogen regulationcould improve the wheat nitrogen accumulation and grain nitrogen content.in thejointing stage and booting stage on wheat. 4． In the low density wheat yield was significantly lower than that in highdensity,the wheat nitrogen uptake efficiency was significantly lower than that inmedium and high density,and nitrogen use efficiency was higher than that in themiddle and high density of wheat. In the condition of low density,2%and6%nitrogen concentration control could improve wheat yield in the range of5%~9.1%at jointing and booting，In the moderate density condition,2%nitrogenregulation in returning can increase wheat yield4.1%; in the jointing stage andbooting stage,2%and6%nitrogen regulation could increase wheat yield4%~5.6%.In the case of high density,2%regulation of nitrogen in can increasewheat yield by4.2%;In the jointing stage and booting stage,2%and6%nitrogenregulation could increase that3.7%~7.6%. Among them, returning wasmainly embodied in the regulation of nitrogen increased grain number per spike,jointing was mainly reflected in the spike, booting was mainly reflected in the1000grain weight. Regulation of nitrogen could increase the utilization rate ofnitrogen.