Abstract:To investigate the leaf aging metabolism of winter wheat under different planting models, three wheat cultivars of cp02(213), cp99(1) and Shaan 512 were used to study the effects of three cultivation models of flat planting, straw mulching, plastic film-mulching) on leaf aging metabolism. The results showed that compared with flat planting (CK),the leaf area, flag leaf function duration, chlorophyll content and the activities of protection enzymes of SOD, POD and CAT in leaves in straw mulching were significantly higher, its malondialdehyde content and over oxidation degree of membrane lipids was lower, the speed of flag leaf aging was slower and the metabolizability was vigorous, which are beneficial to the grain-filling and accumulation of photosynthesis products. At the early grain filling stage, the leaf area, flag leaf function duration, chlorophyll content and the activities of protection enzymes of SOD, POD and CAT in leaves in plastic film mulching were significantly higher than that in CK, while at the late filling stage,there were a remarkable decline of leaf chlorophyll content,a quick leaf aging and a marked increase of MDA content. Among the three wheat cultivars, the leaf aging of Shaan512 was slowly and maintained green well.