玉溪烤烟适产养分临界值施肥体系研究

为研究玉溪烤烟精准施肥方法,采用田间试验研究当季施肥量、土壤养分与‘K326’烟叶产量、净产值的关系。结果表明,各试验点产量、均价、净产值、烟叶品质表现最高的均为N2P2K2（当地推荐施肥量）处理。不同试验点缺肥处理产量与土壤碱解氮、速效磷、速效钾含量之间呈正相关关系,土壤养分校正系数与土壤速效养分含量间的回归方程为y_N=0.3246-0.04lnx_N,y_P=0.7061-0.116lnx_P,y_K=0.6244-0.089lnx_K（y_N、y_P、y_K分别为土壤氮素、磷素和钾素养分有效系数,x_N、x_P、x_K分别为土壤碱解氮、速效磷和速效钾的含量）。根据最佳经济施肥量和植烟土壤中有效养分供给含量,确定在各试验点‘K326’获得优质烟叶的适产养分临界值:海拔1500~1800 m,水稻土为植烟土壤的田烟‘K326’获得2700 kg/hm ²以上优质烟叶的适产养分临界值为N (161.955±18.345) kg/hm ²,P₂O₅ (77.610±12.12) kg/hm ²,K₂O (349.95±45.675) kg/hm ²;海拔在1500~2000 m,以红壤为植烟土壤的地烟‘K326’获得2250 kg/hm ²以上优质烟叶的适产养分临界值为N (138.945±30.705) kg/hm ²,P₂O₅ (65.295±17.34) kg/hm ²,K₂O (306.48±49.905) kg/hm ²。

Fertilization System of Nutrient Critical Value for Optimum Yield of Tobacco in Yuxi

The paper aims to study the targeted fertilizing method of tobacco in Yuxi. A field experiment with tobacco ‘K326’ was conducted in Yuxi to investigate the relationship of the amount of fertilizer applied at current season, soil nutrients data obtained in soil testing, and the tobacco yield and net output. It was found that the tobacco yield, average price, net output and tobacco leaf qualities were all the highest in N2P2K2 treatment plots (local recommended fertilizer amount) in each experiment site. Under the fertilizer-lacking experiments carried out on different sites, the correlations of soil nutrients (alkaline hydrolyze nitrogen, available phosphorus and available potassium) with tobacco yield were significantly positive. The regression equation between soil nutrient contents and soil nutrient correlation coefficient could be expressed as follows: y_N=0.3246-0.04lnx_N, y_P=0.7061-0.116lnx_P, y_K=0.6244-0.089lnx_K (y_N, y_P and y_K was the effective coefficient of soil nitrogen, phosphorus and potassium respectively; x_N, x_P and x_K was the content of soil alkali-hydrolyzed nitrogen, available phosphorus and available potassium respectively). The nutrient critical value for the optimum yield of high quality ‘K326’ was calculated according to the economic optimum application rate and the levels of available nutrients in soil. To achieve the yield of more than 2700 kg/hm ², the nutrient critical values of high quality ‘K326’ planted in the paddy soil at the elevation of 1500-1800 m could be calculated as follows: N was (161.955±18.345) kg/hm ²; P₂O₅ was (77.610±12.12) kg/hm ²; K₂O was (349.95±45.675) kg/hm ². To achieve the yield of more than 2250 kg/hm ², the nutrient critical values of high quality ‘K326’ planted in the red soil at the elevation of 1500-2000 m could be calculated as follows: N was (138.945±30.705) kg/hm ²; P₂O₅ was (65.295±17.34) kg/hm ²; K₂O was (306.48±49.905) kg/hm ².