Abstract:
Mid-term uncovering is one of the important patterns to improve tobacco quality, but the abundant rainy often appears at the late stage of tobacco growth. How to efficiently utilize the film uncovering methods to ensure the growth of tobacco plants and the quality of tobacco, is still lacking. A randomized block design was used to investigate the effects of different film uncovering methods (non-film NF, covering film CF, uncovering film UF, and half uncovering film HF) on the nutrient uptake of tobacco plants, the yield and quality of tobacco. The results showed that film (HF, UF and CF) treatments were higher than NF treatment in terms of plant height, stem girth and number of effective leaves, but the difference between film treatments was not significant, with HF treatment being better. Compared to NF treatment, tobacco leaf yields of HF and UF treatments were significantly 8.85% and 13.07%, and the output values were increased by 12.56% and 16.08%, respectively. The difference in yield among HF, UF and CF treatments was not significant. The uptake and accumulation of N, P and K in HF and UF tobacco plants were higher than that in NF treatment, and the chemical composition of the tobacco leaves was superior. The differences of uptake and accumulation of N, P and K among HF, UF and CF treatments were not significant. The study suggested that that the uncovering film, especially the uncovering half-film method, was conducive to promoting the growth of tobacco plants, increasing the yield of tobacco, improving the quality of tobacco, increasing the nutrients accumulation, and the income of tobacco farmers, which can provide a theoretical basis for field management in tobacco fields.