Abstract: To explore the effect of different groups on the photosynthetic production,yield and quality of flue-cured tobacco during growing period,this research took variety Yunyan 87 as material,built a different flue-cured tobacco groups by setting different sowing dates and planting densities,measured related indicators of the photosynthetic production after each growth period,analyzed economic traits of flue-cured tobacco.The results showed that delaying sowing led to the decrease of the growth period,accumulated temperature,dry matter accumulation,leaf area index (LAI),leaf area duration (LAD) and net assimilation rate (NAR),however the increase of the net assimilation rate (NAR) and crop growth rate (CGR) in late growth period.The most highest dry matter accumulation group was the treatment of 16 500 plant/ha.Dry matter accumulation of mid-leaf,NAR,population mean leaf inclination angle (MLIA) significantly increased with density reducing,but LAI,LAD,CGR,extinction coefficient (K) reduced.With the increasing of planting density,the proportion of mid-high grade and the proportion of mid-leaf were all gradually decreased.The coordination of chemical composition were better in moderate sowing and planting density.Compared with other treatments,the combination of sowing around November 24 and planting density of 16 500 plant/ha had the advantages that the dry matter accumulation was appropriate in the early stage and grew slowly in the middle and late stage.Therefore the total dry matter accumulation was significantly higher and its distribution was reasonable;the combination had better economic characteristics and quality and it alleviated the contradictions of hierarchical structure and location structure effectively.

Key words: Flue-cured tobacco, Sowing period, Density, Photosynthetic production, Economic traits

CLC Number: 

• S572.01