Influences Of Nitrogen-reduced Fertilization On The Production Of Rice Population And Rice Quality And Research On The Nitrogen Reduction Strategy

In China,the long-term objective of devoting exclusive attention to rice production output has led to the universal phenomenon of nitrogen fertilizer application.Moreover,it has also given rise to some issues,such as the low utilization rate of fertilizer,severe resource loss,ecological environment deterioration,etc.In the new situation of development,rice production is in urgent need of high-quality cultivation with efficient resource utilization.For the sustainable development of crop farming,it is an inevitable choice to achieve high yield,efficiency and superb quality based on the constant rate of production.As for the existing varieties and environment of cultivation,guaranteeing stable crop yields with dependable quality attained by the reasonable reduction of nitrogen fertilizers has been considered as a pressing task.This research sets different stages of growth and development for the reduction of nitrogen fertilizer,and analyzes the relationship between the growth characteristics,material production and yield formation of various crop categories.In addition,the influence and mechanism of fertilizer reduction on rice quality formation is further observed.Through conducting research on different modes of nitrogen fertilizer reduction,this research provides the theoretical basis for applying techniques of nitrogen reduction and efficiency enhancement in rice production.Meanwhile,it also offers the necessary approaches and support for high-quality and highly efficient production of rice.Primary results are presented as follows1.Compared with common and local modes of nitrogen fertilizer management,nitrogen fertilizer reduction during a certain period may inevitably induce a dramatic decline of rice inevitable and output.In contrast,during the growth stages,a balanced reduction of nitrogen fertilizer can alleviate or avoid the negative impact of nitrogen fertilizer reduction in a certain period.Despite the decline in available spikes and the number of grains per ear,ripening rates demonstrate a significant increase,thus ensuring the stable levels of ultimate output.With balanced nitrogen fertilizer reduction,spike numbers can be increased by raising the density of planting.The alternation of wetting and drying irrigation can further enhance the ripening rate and thousand kernel weight.Both of the two factors are likely to offset the adverse impact of nitrogen reduction and improve the output of balanced nitrogen reduction,which may even outperform the effect of average nitrogen application in certain conditions.Balanced nitrogen reduction is able to improve the lodging resistance of the rice community,thereby highlighting a more superior capacity of high yield and production than average nitrogen fertilizer treatment.2.Compared with the common nitrogen fertilizer application,a balanced reduction of nitrogen fertilizer significantly optimizes group structures,decreases ineffective tillering and improves the ear-bearing tiller percentage.Besides,it also maintains a relatively high leaf area index,grain-leaf area ratio during the production phases and favorable features of root growth Through combining the balanced reduction of nitrogen fertilizer and improvement of transplanting density,the leaf area index and root system biomass show a dramatic increase during the growth period,while the grain-leaf area ratio and root system activity do not demonstrate apparent decrease.Based on the balanced reduction of nitrogen fertilizer,the alternation of wetting and drying irrigation significantly improves the leaf area index and root growth features.According to these results,the balanced reduction of nitrogen fertilizer is able to improve the group structure,set up an efficient framework of high output.Especially in relatively unfavorable conditions,more stress resistance of group structure characteristics is shown.3.Simple fertilizer for earing,tillering or nitrogen fertilizer reduction may lead to negative impacts on material production and utilization.In comparison,the balanced reduction of nitrogen fertilizer maintains material production prior to heading.Meanwhile,it also enhances the substance accumulation,stem-sheath material transporting and non-structure carbohydrate transporting efficiency,so as to obtain a relatively high growth rate of group growth and net assimilation rate,as well as show favorable features of material production and utilization.As for the balanced reduction of nitrogen fertilizer,SPS,Rubisco enzymatic activity and photo synthetic characteristics are basically equivalent to conventional nitrogen application.However,assimilated substances of spikes also increase apparently,so as to improve the yield and output.With the balanced reduction of nitrogen fertilizer,by increasing the planting density,SPS and Rubisco enzymatic activity decline slightly.However,substance accumulation,transporting volume and collective growth rate increase to some extent.The alternation of wetting and drying irrigation comprehensively increases the substance production and utilization features of a balanced reduction of nitrogen fertilizer.Thus,it can be seen that by combining alternation of wetting and drying irrigation with the balanced reduction of nitrogen fertilizers,substance production,transporting and utilization capacity can be increased significantly during the grain filling stage.4.Nitrogen fertilizer reduction measures decrease the total amount of nitrogen absorption and accumulation to some extent.However,nitrogen utilization efficiency is increased significantly.During the later period of grain filling stage,the balanced reduction of nitrogen fertilizer demonstrates high levels of NR,GS and GOGAT enzymatic activity.Based on the yield and output,the balanced reduction of nitrogen fertilizer demonstrates a favorable capacity of resource utilization and yield improvement.Nitrogen absorption and transporting is enhanced by increasing density.The alternation of wetting and drying irrigation further increases the capacity of nitrogen absorption and utilization for the rice community,showing the positive effects on resource utilization.5.Nitrogen fertilizer reduction is conducive to enhancing the quality of rice.In particular,during the balanced reduction of nitrogen fertilizer,the head rice rate shows no obvious difference compared with conventional nitrogen fertilizer application.chalky grain rate and chalkiness levels decrease significantly,showing favorable processing and exterior quality.Protein and amylose content decreases with favorable gel consistency performance,which reveals the highest level of rice taste.The starch RVA spectrum eigenvalue is comparatively excellent.The highest viscosity and breakdown viscosity is higher than other types of treatment,thus comprehensively showing the superb quality of taste and stewing features.The enhancement of planting density leads to slight declines in processing quality,exterior quality and taste quality of balanced fertilizer reduction.The alternation of wetting and drying further improves the exterior quality and processing quality of rice,posing various impacts on the taste value of different varieties.