Abstract: Field experiments were conducted at the elevations 1000 m and 1300 m in Enshi Autonomous Prefecture of Hubei to study the effects of plastic film mulc
hing in whole growth period and of uncovering plastic film and hilling at rosette stage on the photosynthetic function, yield, and quality of fluecured tobacco Yunyan 87. At the two elevations, plastic film mulching in whole growth period caused a rapid decrease of net photosynthetic rate and leaf chlorophyll content
 at the later growth stages of tobacco, and thus, accelerated the decline of photosynthetic function, and induced the rapid decomposition of assimilation products. At the elevation 1000 m, uncovering plastic film and hilling at rosette stage enhanced the photosynthetic function, increased the assimilation products, and
 improved tobacco yield and quality. At elevation 1300 m, plastic film mulching in whole growth period caused the premature senescence, but maintained the photo
synthetic function and assimilation products at a higher level. It was advocated that in the study area, plastic film mulching in whole growth period and uncovering plastic film and hilling at rosette stage would be appropriate for cultivating flue-cured tobacco at the elevations 1300 m and 1000 m, respectively.

Key words: Ginkgo biloba L, Soil preparation, Fertilization, Modular, Quercetin, Rutin