The Effects Of Nitrogen On The Colony Formation And Grain Yield Of Winter Wheat In Different Planting Density

The tillering of the wheat is developed by the tillering bud,and its growth directly determines whether the tillering can occur normally.Because of the space position and formation time of tillering,there are obvious differences in development process between the tillers in low position and in high position which made significant difference between different stem tillers productivity.The overabundance of the high tillering in wheat causes the group to be large,reduced in order to increase the risk of reverse.The rational wheat group structure is composed mainly of the main stem and the lower tiller stage I and II tillers.So the wheat tiller bud development,regulation of tiller buds grow to form strong low tillers,restrain high tillers,for the construction of neat,high-yield group is of great significance.The nitrogen fertilizer isa significant regulatory role for tiller development and tiller.The nitrogen nutrient can regulate the synthesis of endogenous hormones in the plant,and the hormone regulates the absorption,assimilation and metabolism of nitrogen.Nitrogen and endogenous hormone interactions regulate the growth of tillers and regulate the establishment of wheat communities.Of this study is to set up the laboratory test and field test,laboratory test set up six nitrogen level : 1 mmol L^-1?N1??2 mmol L^-1?N2??4 mmol L^-1?N4??6 mmol L^-1?N6??8 mmol L^-1?N8??10 mmol L^-1?N10?,the analysis of the nutrition physiological characteristic of wheat seedling morphological and,endogenous hormone content on the response of the concentrations of nitrogen,the nitrogen concentration of tillering development regulation function and mechanism.Field experiment set up five planting density : 180×10⁴?D1??270×10⁴?D2??360×10⁴?D3??450×10⁴?D4??540×10⁴?D5?plants·hm^-2,four nitrogen levels:0 kg hm^-2?N0??150 kg hm^-2?N1??225 kg hm^-2?N2??300 kg hm^-2?N3?,a total of 20 processing,research closely fought against each other wheat nitrogen group development dynamic,stem tillers,stem and yield formation of rice productivity differences,explore reasonable composition of wheat population characteristics and appropriate n application rate,for nitrogen nutrition regulation provides the basis of the production of wheat tillering and groups.The main results are as follows:The effect of nitrogen nutrient on the yield of winter wheat in different planting densityAt different density levels,the corresponding relationship between the amount of nitrogen and the yield was significantly different.In D1 planting density,the output increases linearly with the increase of nitrogen and nitrogen.Under the conditions of D2,D3,D3 and D5,the yield of nitrogen is far higher than that of the non-nitrogen condition,and the increase of the yield of the nitrogen is decreased after the increase of the output.The production density of D2,D3,and D4 is the highest yield of 150 kg hm^-2.When the density was D5,225 kg hm^-2 treatment was the highest yield.In different planting densities,the effect of increasing the amount of nitrogen in theproduction component of the yield component was also apparent.Under the planting density of D1,increasing the nitrogen fertilizer and increasing the number of panicles and the number of panicles per unit area,the grain weight loss was not obvious.Under the density of D2,compared with the N1 treatment,the product of the increase in the number of grain of n fertilizer and the number of the area of the area of the area of the area is not small,the grain weight is decreased obviously,and the output is decreased.Under the density of D3,compared with the N1 treatment,the difference in the number of grains in the spike was not significant,the unit area was the number of ears,the grain weight was decreased significantly,and the output decreased.Under the planting density of D4,the number of panicles per unit area and the weight of 1000-grain are decreasing,but the difference is not significant,the number of panicles is decreased significantly,and the output decreases.Under D5 planting density,the area of N2 treatment unit area is significantly higher than other treatment,so the yield is highest.The effect of nitrogen nutrient on the growth of the wheat stalk in winter wheat under different planting densityCompared with no nitrogen,nitrogen fertilizer significantly improved the tillers of the single stem productivity,make advantage stems tillers expanded,N1 n application to continue applying nitrogen fertilizer,on the basis of grouping of advantages stem tillers,increase of nitrogen increase tillering ear are weak tillers group.Under D1?D2 planting density,the main stem and primary tillers ?,? belong to stem tillers group in nitrogen fertilizer treatments,the other tillering is a weak stem tillers group;In N1 treatment,processing advantages tillers Stanley,the highest proportion,with the increase of n application advantages stem tillers spike weight decreasing,but significantly higher nitrogen treatment;D3 planting density,N1,N3 treatment,advantages stem tillers group contains main stem and tiller ?,N2 processing advantages stem tillers group includes main stem and tiller ?,?,with the increase of n application advantages stem tillers into spike weight increase after the first drop;D4,D5 density treatment,both are only main stem stem tillers group,other tillers are vulnerable stem tillers group,under the condition of nitrogen N1 processing advantages stem tillers Stanley,the highest proportion,but not lower than single treatment.Under the condition of each density,reducing the amount of nitrogen fertilizer is beneficialto increase the proportion of tiller.Considering production stem tillers,with groups in production should be suitable for increasing planting density,in order to make sure the ear number,and reduce nitrogen,in order to improve the advantage of stem tillers spike weight,a higher yield.This study suggests that 360 x 10⁴ strains of hm^-2 450 times 10⁴ strains of hm^-2,and 150 kg of h-2 nitrogen levels,are the most favorable for yield formation.The regulation and mechanism of the growth of tillering bud development of nitrogenNapplication rate should significantly affect the plant nutrition of the wheat seedling.With the increase of n application,the nitrogen content of the aboveground plant is increased,and the photosynthetic performance is enhancements,aboveground dry matter accumulation increased;The root system contains the increase of nitrogen,but the root dry matter accumulates decline,the total root length,the root surface area,the number of root tip has obviously decreased.The N8 process was down to 62 per cent,and the N8 was only about 25 per cent.With the increase of n application,tillering ?,?,? incidence were reduced after rising first,N6 processing ?,?,? highest incidence of tillering,N1 processing ?,?,? tillering rate lowest.This indicates that the occurrence of tillering need a certain amount of nitrogen nutrition,but nitrogen concentration is too high,can inhibit tillering,and increased with managed for a sensitivity for nitrogen concentration in the reaction.The levels of ZT + ZR and IAA increased significantly as the amount of nitrogen increased.Compared with the N1 processing,the N4's roots are raised 3.9 and 0.93 times respectively,respectively,with the root ZT + ZR and IAA.The root ZT + ZR and IAA are improved 8.5 and 3.1 times respectively,indicating that the ZT + ZR content is more apparent in the nitrogen response.