Study On N Efficiency Of Different Rotary Tillage Depth Fertilizer And Planting Density In Rice

In order to study the effects of different rotary tillage depths and nitrogen application rates on nitrogen use efficiency of different rice cultivars,a field experiment was conducted to analyze the effect of nitrogen rates and different planting densities by rotary tillage methods on yield and yield components,physiological characteristics,nitrogen accumulation,distribution,and nitrogen use efficiency of rice.The experimental results were showed as follows:1.Effect of different treatment on rice yield and yield componentsThe yield of N3 treatments of Gengyou165 was the highest,which was significantly higher than other treatments.The yield of N3 treatment of shallow rotation Shendao505 was higher than other treatments.The number of effective panicles was higher in N3 treatments than in other treatments;deep rotation was excellent in Gengyou 165 and shallow rotation,while Shendao 505 was the highest in N1 treatment.The treatment of N3 in two varieties with deep seeding per panicle was significantly higher than other treatments.There was a significant positive correlation between yield and effective panicle number of Gengyou 165 and Shendao 505.2.Effect of different treatment on agronomic traits of riceUnder the conditions of deep rotation and shallow rotation of the two varieties,the rate of emergence showed that N3 was higher than N1 and N2,and the whole treatments was higher than that of shallow rotation.The final tiller number and the ear formation rate of the deep-spinning rice 505 were the highest,and the highest tiller number of the shallow-spinning rice 505 was the largest.Under the deep rotation and shallow rotation treatment,the ear length of the Gengyou 165 was significantly higher in N1 treatments than other treatments.The ear length of rice 505 was significantly higher in N3 treatment than in other treatments.3.Effect of different treatment on physiological characteristics of riceThe maximum SPAD of the two cultivars under the conditions of deep rotation and shallow rotation were all treated with N3.Under different treatments,the leaf area index of N3 treatments was significantly higher than that of the other three treatments,and Gengyou 165 was higher than Shendao 505,shallow rotation and deep.The rotation treatments trend was consistent,and the leaf area index was deeper than the shallow rotation;the net photosynthetic rate of each treatments was higher than that of Shendao 505.The dry matter accumulation of Gengyou 165 and Shendao 505 at heading stage and mature stage was significantly higher than that of shallow rotation treatment,and Shanyou 165 was higher than that of Shendao 505,and the highest value was observed in N3 treatment;The growth rate of the population at maturity was higher than that of deep rotation,and Gengyou 165 was higher than that of Shendao 505,and both reached the highest value in N3 treatments.4.Effects of different treatments on nitrogen accumulation,distribution and nitrogen use efficiency of riceThe nitrogen content and nitrogen accumulation of different parts of the plants were significantly higher than those of the other three fertilization treatments in the treatments of deep rotation N3,and the nitrogen accumulation in each part of Gengyou 165 was higher than that in Shendao 505.Shendao 505,deep rotation treatment is higher than shallow rotation.The nitrogen utilization rate and nitrogen fertilizer partial productivity of Gengyou 165 were significantly higher than other treatments under N2 treatment;the nitrogen agronomic efficiency of the two varieties was significantly higher than that under other conditions under deep rotation treatments under N3 fertility conditions.Treatment;the nitrogen agronomic efficiency and nitrogen use efficiency of the two varieties showed the highest value under the treatment of deep rotation N3,and the deep rotation was higher than the shallow rotation.