Abstract: 【Objective】The effects of modified atmosphere packaging and commercial polyethylene film packaging on lignification in bolting stem of Chinese flowering cabbage and the expression patterns of cell wall related enzyme genes were investigated to provide a theoretical basis for the study of preservation,storage and lignification regulation mechanism of Chinese flowering cabbage.【Method】Ningxia Sijiu flowering cabbage was as the material.The physiological indexes and the contents of O₂ and CO₂ of Chinese flowering cabbage packaged in three kinds of packaging bagsmodified atmosphere packaging (MP20,MP30) and commercial polyethylene film packaging(control)were determined respectively,during storage period(8 d) at room temperature(25℃).And the expression pattern of cellulase gene(BrCEL3),xyloglucan transglucosylase (BrXET2 and BrXET3) and β-mannanase enzyme gene (BrMAN1,BrMAN5 and BrMAN6) were analyzed by real-time fluorescence quantitative PCR.【Result】During storage,MP20 and MP30 modified atmosphere packaging bags could effectively delay the increase of stem hardness and reduce water loss.And the composition of the gas in the bag changed,forming a low O₂ and high CO₂ atmosphere.At the end of storage,the bolting stems in MP20and MP30 groups were still contained higher soluble protein content (0.54 and 0.93 mg/g) and vitamin C content (0.45and 0.62 mg/g).Modified atmosphere packaging inhibited the increase of activities of phenylalanine ammonia-lyase(PAL) and peroxidase(POD),which were the key enzymes in lignin synthesis,and also reduced the accumulation of lignin and cellulose content.At the end of storage,the lignin contents of the bolting stems in MP20 and MP30 modified atmosphere packagings were 0.28 and 0.27 mg/g,decreased by 12.50%and 15.63%compared with the control,respectively,while the cellulose contents were 4.16 and 4.60 mg/g,decreased by 32.57%and 25.41%compared with the initial value,respectively.Modified atmosphere packaging inhibited the increase of malondialdehyde(MDA) content,the content of MDA was significantly lower than that of control group after 4 to 8 d of storage (P<0.05).The expression trends of BrCEL3 and BrMAN5,BrXET2 and BrXET3,BrMAN1 and BrMAN6 genes were similar,and the expression levels of these genes in modified atmosphere packaging were lower than control group (except for day 4 in MP20 group).【Conclusion】Modified atmosphere packaging effectively reduces the accumulation of lignin and cellulose in bolting stem of Chinese flowering cabbage,and slows down the lignification process.Through comprehensive analysis,the MP30 modified atmosphere packaging is more beneficial to the preservation and slowing down the lignification of bolting stems of Chinese flowering cabbage.