Effects of Phosphorus Fertilizer Amount on Nutrient Accumulation and Flue-cured Tobacco Yield and Quality in Phosphorus-rich Soil

In order to explore the suitable amount of phosphorus application in phosphorus-rich soil, field experiments were conducted to study the effects of different phosphorus application rates (0, 63, 94.5, 126, 157.5, 189 kg/ha) on nutrient accumulation, yield and quality of flue-cured tobacco. The results showed that: (1) As the phosphorus application increasing, tobacco dry matter mass showed the trend of first increasing and then decreasing. (2) Compared with the control treatment, the accumulation of nitrogen, phosphorus and potassium in leaves, shoots and whole plants was increased with the phosphorus application of 94.5, 126, 157.5 and 189 kg/ha, and the highest nutrient accumulation was obtained by the 157.5 kg/ha treatment. (3) When compared with other treatments, the best yield, the biggest proportion of superior tobacco and the highest output value were obtained by the 94.5 kg/ha treatment, increased by 4.24%-23.29%, 1.93-17.36 percentage point, and 3.26%-37.46%, respectively. (4) The best apparent utilization rate of phosphorus was obtained by the 94.5 and 157.5 kg/ha treatments, which was significantly higher than that of the 63 kg/ha and the control treatments. (5) The oil content of the upper leaf and the aroma content of the middle leaf were decreased by applying too much phosphorus fertilizer (157.5 and 189 kg/ha) on the phosphorus-rich soil. In conclusion, the tobacco leaves with better yield, output value and quality can be obtained with the phosphorus application rate of 94.5 kg/ha in Enshi.