西南农业学报2026，Vol.39Issue(2)：337-347,11.DOI:10.16213/j.cnki.scjas.2026.2.011
采后中上部烟叶衰老过程中呼吸代谢特征研究
Respiratory metabolic characteristics of middle and upper postharvest tobacco leaves in senescence process
摘要
Abstract
[Objective]The present paper aimed to explore the relationship between senescence characteristics and respiratory metabolic path-ways of postharvest tobacco leaves.[Method]The middle and upper tobacco leaves of K326 were used as test materials to carry out the camer-a obscura test.The color changes of tobacco leaves during senescence were observed,and the production rate of superoxide anion radical(O2-·),the contents of hydrogen peroxide(H2O2)and malondialdehyde(MDA)were determined.Additionally,the activities of key en-zymes involved in glycolysis(EMP),the tricarboxylic acid cycle(TCA),and the pentose phosphate pathway(PPP),as well as the contents of pyridine nucleotides such as NAD(H)and NADP(H),were measured.[Result](ⅰ)The overall senescence rate of the upper leaves was faster than that of the middle leaves.As evidenced by more rapid browning,a higher O2-·production rate,and faster accumulation of H2O2 and MDA.(ⅱ)Compared with the middle leaves,the activities of hexokinase(HK),phosphofructokinase(PFK),pyruvate kinase(PK),citrate synthase(CS),α-ketoglutarate dehydrogenase(α-KGDH),succinate dehydrogenase(SDH)and NAD(H)contents in the upper leaves EMP-TCA were up-regulated at most postharvest time points.(ⅲ)During the postharvest senescence process,especially at the brown-ing stage(4-8 days after harvest),the activities of glucose-6-phosphate dehydrogenase(G6PDH)and 6-phosphogluconate dehydrogenase(6PGDH)in the PPP,as well as the NADPH content,were significantly higher in the middle leaves than in the upper leaves.[Conclusion]EMP-TCA metabolism is more vigorous in the upper leaves after harvest,which increases the consumption of respiratory substrates,making se-nescence browning more likely to occur.In contrast,the overall EMP-TCA activity in the middle leaves is lower,and respiratory metabolic re-sources preferentially allocated to the PPP,resulting in a higher PPP metabolic flux,and thus showing a stronger anti-senescence ability.关键词
衰老/采后烟叶/糖酵解/三羧酸循环/磷酸戊糖途径Key words
Senescence/Postharvest tobacco leaves/EMP/TCA/PPP分类
农业科技引用本文复制引用
张宜冰,胡彬彬,王廷贤,邓明军,杨占伟,宋朝鹏,魏硕,王卫峰..采后中上部烟叶衰老过程中呼吸代谢特征研究[J].西南农业学报,2026,39(2):337-347,11.基金项目
中国烟草总公司科技项目(国烟科[2021]55号) （国烟科[2021]55号）
中国烟草总公司广西壮族自治区公司资助项目(202445000024032) （202445000024032）
云南省烟草公司科技计划项目(2023530000241022) （2023530000241022）
