Effects Of Interaction Of Nitrogen Fertilizer Level And Sowing Density On Yield And Dry Matter Accumulation And Transport Of Oats

Using Baiyan No.2 as a test material,a randomized block design was used to study the effects of interaction between nitrogen fertilizer and planting density on yield and dry matter accumulation and transport of oats,in order to investigate the optimal combination of oat yield and dry matter accumulation to grain transport.Nitrogen fertilizer levels and sowing density,the main findings are as follows:1 Effect of interaction of nitrogen application rate and seeding density on growth andyield of oatsNitrogen application rate and seeding density had a significant effect on the emergence rate of oats.When the nitrogen application rate was 193 kg/hm~2 and the seeding density was 100 kg/hm~2,the seedling emergence rate had a maximum value of 71.74%.Nitrogen application rate at tillering stage had the greatest effect on plant height,and the plant height increased significantly with the increase of nitrogen application rate.Under each nitrogen application,the plant height showed a downward trend with increasing planting density and the significant difference among planting densities.Sprouting density had the greatest effect on plant height at the jointing stage and mature stage,and the effect of interaction between the heading stage and nitrogen application rate and sowing density at the filling stage had the greatest effect on the plant height.The amount of nitrogen applied is the primary factor affecting the delivery of oats.The interaction between nitrogen application rate and seeding density is the primary factor affecting the dry-fresh ratio and root-shoot ratio.The influence of planting density on the dry-fresh ratio is less than the interaction of two factors at the jointing stage.The amount of nitrogen applied during maturation is less than two factor interaction effects.Nitrogen application rate had no significant effect on root-shoot ratio,but planting density had a significant effect on root-shoot ratio at jointing stage.Sowing density had no significant effect on root-shoot ratio at the grain-filling stage and mature stage.Sowing density is the primary factor affecting aboveground biomass.Nitrogen application at the jointing stage is the primary factor affecting the underground biomass.Sowing density during the filling stage is the primary factor affecting the underground biomass.The effect of nitrogen fertilizer and density on the panicle length was significant,with a maximum panicle length at a nitrogen concentration of 49 kg/hm~2 and a density of 250 kg/hm~2.The amount of nitrogen was 49 kg/hm~2,and the maximum number of spikelets was250 kg/hm~2.The effect of density on spikelet number was not significantly different when nitrogen was low,and there was a significant difference between density treatments when nitrogen was high.There was no significant difference in the effect of nitrogen fertilizer on the number of spikelets per spike.With the increase of nitrogen amount,there was a significant difference among the density treatments.The number of spikelets was the highest when the nitrogen amount was 145 kg/hm~2 and the density was 250 kg/hm~2.The panicle weight per ear was the heaviest when the nitrogen amount was 49 kg/hm~2 and the density was 100 kg/hm~2.Nitrogen fertilizer and density had a significant effect on the number of grains per panicle,and the amount of grains per panicle was the highest when the amount of nitrogen was 49kg/hm~2 and the density was 250 kg/hm~2.Nitrogen fertilizer was positively correlated with yield and its constituent factors and had the greatest impact effect.The mathematical relationship between nitrogen fertilizer and density and yield was established and the regression equation was obtained:Y_g=640.1163-5.0752D+0.5501N+0.0173D~2+0.0355N~2,R~2=0.8589***This equation fits well with the actual situation.It has a certain representation and the amount of nitrogen applied is the primary factor affecting the grain yield of oats.A reasonable close planting under a suitable nitrogen application rate can effectively predict oat grain yield based on this equation.With the increase of nitrogen application rate,the dry and fresh grass yield and the dry and fresh weight of straw during the mature period are on the rise.The planting density is the primary factor affecting the grass yield.The yield of hay was the highest when the nitrogen application amount was 193 kg/hm~2 and the seeding density was 150 kg/hm~2.The fresh grass yield was the highest when the nitrogen application amount was 193kg/hm~2 and the seeding density was 100 kg/hm~2.During the mature period,the fresh weight of straw was the highest when the nitrogen application rate was 145 kg/hm~2and the seeding density was 100 kg/hm~2.The dry weight of the straw was the highest when the nitrogen application amount was 193 kg/hm~2 and the seeding density was150 kg/hm~2 during the mature period.The mathematical relationships between nitrogen application rates and planting densities and dry and fresh yields were established,respectively,and regression equations were obtained:Y_h=2420.1061-19.8481D+0.5856N+0.0505D~2+0.0150N~2,R~2=0.7427**Y_f=6013.0804-44.3532D-1.2373N+0.1051D~2+0.0295N~2,R~2=0.8825***2 Effects of interaction of nitrogen application rate and seeding density on dry matter accumulation,transport and physiological indexes of oatsThe amount of nitrogen applied had a significant effect on the accumulation and distribution ratio of dry matter in grains during mature period.The accumulation of dry matter in grains showed an upward trend with the increase of nitrogen application rate during mature period.The impact of sowing density on the accumulation of dry matter in the mature grain was not significant,and there was a significant difference in the distribution ratio of grain dry matter accumulation at maturity.When the nitrogen application rate was 193 kg/hm~2 and the seeding density was 150 kg/hm~2,the dry matter accumulation of the grain was the largest during the mature period.The effects of nitrogen application rate and sowing density on the dry matter weight and dry matter transport during ripening were extremely significant.The interaction between nitrogen application rate and sowing density was the primary factor influencing the dry matter transport of vegetative organs before flowering.The dry weight of the seeds was the highest when the nitrogen application amount was 145kg/hm~2 and the seeding density was 100 kg/hm~2.The amount of dry matter in the vegetative organs before flowering was the highest when the nitrogen application rate was 97kg/hm~2 and the seeding density was 100kg/hm~2.When the nitrogen application rate was 145 kg/hm~2 and the seeding density was 150 kg/hm~2,the dry matter transport rate of the vegetative organs before flowering was the largest.When the nitrogen application rate was 145 kg/hm~2 and the seeding density was 200 kg/hm~2,the dry matter transport of the vegetative organs before flowering had the largest contribution to the grain.The effect of nitrogen application rate and the interaction of the two factors on the SPAD value was extremely significant,and the effect of nitrogen application rate was greater than the interaction effect of the two factors.The SPAD value was the highest when the nitrogen application amount was 193 kg/hm~2 and the seeding density was 250 kg/hm~2.Nitrogen application rate and sowing density and their interactions had significant effects on the changes of soluble protein content,and the sowing density was the primary factor affecting the soluble protein content.The soluble protein content was the highest when the nitrogen application amount was 97kg/hm~2 and the seeding density was 100 kg/hm~2.Nitrogen application rate and sowing density and their interactions had significant effects on the starch content of the grain and the sowing density was the primary factor affecting the starch content.The starch content was the highest when the nitrogen application amount was 193 kg/hm~2 and the seeding density was 100 kg/hm~2.