Effects Of Ground Plastic-Covering On Tobacco's Growth Development And Nutrient Absorption

The technique of ground plastic-covering on tobacco began to apply in the 1950 s. There are many investigations based on this technique by China and foreign countries1 scientists. Generally speaking, the technique of plastic covering plays an important role in tobacco production, such as improving soil temperature, water and soil conservation, maintaining and advancing soil fertilization, reducing nutrition runoff. Ground plastic covering can promote tobacco developing earlier and advance the tobacco quality and yield. According to this experiment we investigated the effect of different periods of ground plastic covering with different N levels on the tobacco growth development, nutrient absorption, quality, output and production value. The main results are as follows: The results show that ground plastic covering is helpful to the growth of flue-cured tobacco leaf area and the accumulation of dried matter in the stems. The daily accumulation peak in dry matter appeared ten days earlier than the tobacco seedling uncovered. It was suggested that uncovering ground plastic in extending-root stage could regulate and improve tobacco growth during the period of middle and late stages. The technique of ground plastic covering can promote nutrient absorption in the early stage, which can advance nitrogen-use efficiency and regulate the chemistry components in the tobacco leafs. So the quality of tobacco leaf was improved. When the leafs matured enough, percentage of prime tobacco leaf was increased by 4-7 percent, which can improve the output and production value significantly.