Effects of Different Mulching Patterns on Physoilogical Characteristics,Yield and Quality of Flue-cured Tobacco

The experiment was carried out to study the effects of different mulching patterns on physiological characteristics,yield and quality of flue-cured tobacco in the field condition with the flue-cured tobacco(Nicotiana tabacum L.) cultivar K326.The results showed that,in comparison with no mulching,the treatment of mulching in the early growth stage and then removing film and ridging soil as well as covering with rice straw during the blooming stage(early mulch and later straw) could increase root biomass and activity,enhance net photosynthetic rate of leaves,decrease the transpiration rate and increase the water use efficiency of flue-cured tobacco leaves.Moreover,it was also found that the flue-cured tobacco leaf area enlarged,the specific leaf weight decreased,and the weight per leaf increased.But the root activity,photosynthetic rate and water use efficiency of flue-cured tobacco leaves remarkably declined under the treatment of mulching by film during the whole period,which could accelerate the caduceus procedure.Moreover,the yield,average price,value and percentage of superior leaves under the treatment of early mulch and later straw were higher than those of other treatments,which also could change the chemical composition of flue-cured tobacco leaves.