Effects Of Different Mulching Measures Of Water Saving On Soil Environment Of Tobacco Field, Yield And Quality Of Flue-cured Tobacco

The plot and field experiments were conducted to study the effects of different cultivation measures of rain collection by mulching on soil water, soil available K, dry matter, N P, K accumulation and distribution, water use efficiency, yield and quality of tobacco field at Luoning county from 2003 to 2004. The results were showed as follows:1. Straw mulching and straw-film mulching could increase water content of top soil in tobacco field significantly, but their water content in deep layer were lower than that of CK during early and middle stages of tobacco growth. Water content in each layer increased gradually with tobacco growth. Each mulching measure could increase the water content in 0~ 100cm soil layer, the order of the water content in 0~ 100cm soil layer at picking stage from high to low was: straw-film mulching > straw mulching > straw mulching and ploughing > straw-film mulching and ploughing > CK > film mulching.2. Soil available K decreased with tobacco growth and depth of soil layer, it was different significantly in top soil layer of each treatment. In the rosette stage, all treatments could increase the content of soil available K, the effect of film mulching treatment was the most significant, the difference between the effects of straw mulching treatment and straw-film mulching treatment was not remarkable. At picking stage, the film mulching treatment had the lowest soil available K, the soil available K content of CK treatment was slightly higher than that of film mulching treatment, there was not significant difference among others treatments. In straw mulching condition, the soil available K and slow-released K went up with the rising of the K fertilizer application, went down with the growth of tobacco, the decline of the soil available K content was rapid in the early stage and slow in the late stage, while the soil slow-release K was slow in the early stage and rapid in the late stage.3. In different growth phase, the K content in green leaves was rising with the increasing rate of potassium application. With promotion of breeding time, the K content in green leaves of all treatment declined. In picking stage, the change of K...