Abstract: By studying of the tillering dynamics and yield composition changes of Zhenzhunuo under different nitrogen fertilizer levels, the effects of nitrogen fertilizer on tiller panicle formation, yield and yield composition factors of Zhenzhunuo were explored,and the economic benefits under different nitrogen levels was determined, to optimizethe fertilization mode, and provide references for the efficient application of this variety in production. The results showed that the tillering number of Zhenzhunuo increased with the increase of nitrogen fertilizer level. The range of tiller panicles was 60.73% to 78.54% under different treatments. Too much or too little nitrogen fertilizer will lead to the delay of start heading stage and full panicle stage, and the mature stage was the latest at the level of 202.5 kg/hm² nitrogen. Among the yield components of each treatment, the effective panicle increased with the increase of nitrogen fertilizer, the seed setting rate decreased with the increase of nitrogen fertilizer, and the 1000-grain weight increased first and then decreased with the increase of nitrogen fertilizer. The 1000-grain weight was the highest at the level of 157.5 kg/hm² nitrogen. The yield increased first and then decreased with the increase of nitrogen fertilizer, and the yield was the highest at the nitrogen applicaiton level of 157.5 kg/hm². The agronomic efficiency of nitrogen fertilizer first increased with the increase of nitrogen fertilizer, and then began to decline after the nitrogen application level of 180.0 kg/hm². According to the fitting equation, the economic benefit reached the maximum when nitrogen was used at 96.88 kg/hm². In conclusion, under the appropriate conditions of P and K fertilizer, the yield structure of this variety is more reasonable, the yield is the highest, the group quality is higher, and the comprehensive benefit is better when the nitrogen fertilizer（N） use is 157.5 kg/hm².

Key words: Zhenzhunuo, tillering dynamics, yield structure, nitrogen fertilizer