Effects Of Nitrogen Rate On Grain Yield,Quality And Nitrogen Use Efficiency In Weak Gluten Wheat Varieties

In this experiment,nine weak gluten wheat varieties such as Yangmai 13 and Ningmai 13 were selected as materials,and the variety comparison test,nitrogen level test and micro-area test were set up.Explore the weak gluten wheat varieties suitable for planting between Jianghuai and Huaihe River,explore the effect of nitrogen fertilizer application on the yield and quality of weak gluten wheat,and regulate the amount of nitrogen on nitrogen absorption and utilization of weak gluten wheat The results are as follows:According to the characteristics of the varieties,it is an effective way to achieve high yield by adjusting the relationship between the number of panicles,the number of grains per panicle and the grain weight Ningmai 13 and Ningmai 9 had good yield and protein content of 12.08%and 12.37%,respectively,which met the national standard for weak gluten wheat.The activity of GS enzyme in the middle and late filling stage plays a key role in the formation of wheat grain quality.The activity of ADPG in the early filling stage had a significant effect on the grain quality of weak gluten wheat The volume distribution of starch granules in weak gluten wheat varieties was bimodal,and the number distribution was single-peak.The surface area distribution had three peaks and two peaks.In the quantitative distribution,the starch granules mainly consist of B-type starch granules,and the Ningmai 9 A-type(>10 um)starch granules contribute the best to the volume.The peak viscosity was negatively correlated with the volume and surface area percentage of type B(<10 ?m)starch granules and positively correlated with type A starch granules.The gelatinization temperature was negatively correlated with 0.55-2.8 ?m,2.8-10 ?m and type B starch granules and volume percentage,and positively correlated with the volume percentage of type A starch granules.There was no significant correlation between the trough viscosity,the final viscosity,the dilute value,the rebound value,and the volume percentage of starch particles with diff rent particle sizes.The number of panicles and grains per panicle increased with the increase of nitrogen application rate.Nitrogen application had no significant effect on grain weight The yield rose first and then decreased with the increase of nitrogen application rate.The increase of nitrogen application rate can significantly increase the content of grain protein and protein components.Among them,Ningmai 13 and Yangmai 13 had a protein content of less than 12.5%when nitrogen application rates were 0 kg·hm-2 and 105 kg·hm-2,which met the national standard for high-quality wheat The application of nitrogen fertilizer in a certain range can increase the activity of GS enzyme in the middle and late filling stage of grain,promote the synthesis of protein,and improve the grain protein content of wheat The activity of ADPG in wheat grain decreased significantly with the increase of nitrogen application during the middle and late filling stages.Grain weight changes of weak gluten wheat showed an "S" curve,showing a"slow-fast-slow" trend.Appropriate application of nitrogen fertilizer can increase the filling rate of wheat during the middle and late filling stage.Increasing nitrogen fertilizer in a certain range can increase the potential value(K)of 1000-grain weight of weak gluten wheat,delay the occurrence of the maximum rate of grain filling,and prolong the duration of grain filling.The average filling rate(R)and the maximum filling rate(Rmax),and the average filling rate of R2 and R3 are extremely significantly positively correlated with the start-up potential(CO)and the continuous days t2 and t3 at each filling period.The duration is negatively related to the filling duration.(D)Negative comlation.The duration of filling(D)was significantly positively correlated with the maximum filling time(Tmax)and the duration of each period of grain filling(t2,t3),and was significantly positively correlated with the start-up potential(CO).The grain weight was significantly positively correlated with the duration of days(tl)during each period of grain filling.Nitrogen fertilizer application within a certain range of nitrogen application can increase the volume percentage and surface area percentage of type B(<10 ?m)starch grains.In conparison,type A(>10 ?m)starch grains decreased.The number distribution of A-type and B-type starch granules in weak gluten wheat was not significantly affected by the amount of nitrogen applied.Nitrogen application rate had no obvious effect on starch gelatinization temperature of weak gluten wheat.The low viscosity,final viscosity and rebound value of starch in weak gluten wheat increased with the increase of nitrogen application.Appropriate application of nitrogen fertilizer can increase the peak starch viscosity of wheat and the weak value of starch dilute value of wheat with weak gluten is not obviously affected by the amount of nitrogen applied,which is mainly determined by the variety factor.The nitrogen accumulations of plant and grain in the weak gluten wheat at the flowering stage were significantly higher with the increase of nitrogen application rate.Under different nitrogen levels,the nitrogen and nitrogen accumulations from weak and gluten wheat plants at the flowering and maturing stages were all increased with the increase of nitrogen application rate,and the soil nitrogen was significantly higher than those from the soil The translocation rate and contribution rate of nitrogen to grain in vegetative organs of weak gluten wheat decreased with the increase of nitrogen application rate.The nitrogen fertilizer production efficiency and nitrogen fertilizer use efficiency of both varieties showed a decrease with the increase of nitrogen application rate.