Abstract:

Deeper tillage has been commonly thought having positive effect on plant growth, but what depth for tillage is better is not clearly in tobacco production. A field experiment was conducted to investigate the effect of tilling depth (20, 30, and 40 cm, respectively) on the growth, root distribution, dry matter accumulation, nutrient uptake, yield and quality of flue–cured tobacco plant in Shilin county, Yunnan. The results showed that tobacco plant growth was significantly affected by the tilling depth from topping to harvesting except the early stage. The number and dry weight of roots decreased with increasing tilling depth at the 0–10 cm soil layer, but increased at the 10–20 cm and 20–30 cm soil layers, and more roots were found for the treatment with tilling depth at 40 cm. Leaf area index, maximum leaf area, dry matter accumulation and uptake of nitrogen, phosphorus and potassium increased in the plant with deepening tilling depth. The highest yield and economic value of flue-cured tobacco leaves were obtained at 40 cm of tilling depth. Moreover, the 30 cm of tilling depth was also better for higher yield and higher quality of leaf. It suggested that 30 to 40 cm was the optimum tilling depth for flue-cured tobacco.

Key words: Flue-cured tobacco, Tilling depth, Root, Dry matter accumulation, Nutrient uptake, Yield, Quality