Objective The research aims to investigate the effects of nitrogen application rates on growth, yield, output value and quality of cigar in order to provide a basis for rational application of nitrogen fertilizer in cigar filler planting in Shifang, Sichuan Province.

Method With Dexue 3 (cigar filler) as material, the variation characteristics of agronomic characters, yield, output value, physical quality and chemical composition of tobacco plants under different nitrogen application rates (0, 60, 120, 150, 180 and 240 kg/hm², which were recorded as N0, N60, N120, N150, N180 and N240, respectively) were analyzed by field experiment.

Result Nitrogen application rate had little effect on agronomic character indexes of cigar at topping stage (44 days after transplanting). With the increase of nitrogen application rate, the yield and output value of tobacco leaves increased rapidly at first, then the yield increased slowly, and the output value decreased instead of increasing. Compared with N0 treatment, the yield and output value of nitrogen treatment obviously increased by 11.62%-57.62% and 10.11%-45.83%, respectively. Among them, the highest yield of tobacco leaves under N240 treatment was 2 737.18 kg/hm², while the highest output value of tobacco leaves under N180 treatment was 99 834.63 yuan/hm², both higher than those under N150 treatment, but there was no significant difference between treatments. With the increase of nitrogen application rate, the proportion of high-quality grade 1 and grade 2 tobacco leaves increased first and then decreased, while the proportion of lowquality grade 3 and lowest grade tobacco leaves presented an opposite trend, among which grade 1 and grade 2 tobacco leaves under N120 and N150 treatments accounted for the largest proportion, both reaching more than 80%. The comprehensive scores of physical quality and chemical composition of cigar leaves increased first and then decreased with the increase of nitrogen application rate. Among them, the coordination of physical quality and chemical composition of tobacco leaves treated with N120 was relatively better, and the comprehensive scores of physical quality and chemical composition of tobacco leaves were the highest, which were 8.58 and 7.58, respectively,

Conclusion Suitable nitrogen application rate can increase the yield and output value of cigar tobacco, increase the proportion of high-quality tobacco, improve the physical quality of tobacco, and coordinate the chemical composition. Considering the yield, output value and quality of tobacco leaves, the reasonable nitrogen application rate of cigar filler in Shifang of Sichuan Province is 120-150 kg/hm².