适产养分临界值模型对玉溪烤烟产质量的影响

为验证烤烟适产养分临界值模型的有效性和适用性，采用田间试验，研究适产养分临界值模型对烟叶产质量的影响。结果表明，适产养分临界值模型推荐施肥量(T3)比常规推荐施肥量(T2)低58.9 kg/hm²，减施化肥对烤烟农艺性状影响不大，但可以提高产质量、肥料贡献率和肥料农学利用率。2019年T3处理产量比T2处理高7%，产值比T2处理高11%，肥料贡献率比T2处理高5.1个百分点，肥料农学利用率比T2处理高53.8%。2020年T3处理产量比T2处理高7.2%，产值比T2处理高8.5%，肥料贡献率比T2处理高4.9个百分点，肥料农学利用率比T2处理高43.9%。运用灰色关联度分析法对3个处理烟叶中部叶和上部叶化学成分进行综合评价并排序，中部叶排序为T3>T1>T2，上部叶排序为T3>T2>T1。本研究2年田间试验的结果表明，适产养分临界值施肥模型与常规推荐施肥相比，在烤烟生长、烤烟产量和品质、经济效益和肥料利用率方面都有全面和显著的改善，可以达到精准施肥的目标，为烤烟施肥管理提供了一条可靠、实用的途径。

Influence of Fertilization System of Nutrient Critical Value for Optimum Yield of Tobacco on Yield and Quality of Flue-cured Tobacco in Yuxi

The paper aims to verify the validity and applicability of the fertilization system of nutrient critical value for optimum yield of tobacco. A field experiment with tobacco ‘K326’ was conducted in Yuxi to investigate the effects of the model on yield and quality of tobacco. It was found that the recommended fertilization amount (T3) by fertilization system of nutrient critical value for optimum yield of tobacco was 58.9 kg/hm² lower than that of the conventional recommended fertilization amount (T2). Reducing fertilizer application had little effect on agronomic traits of flue-cured tobacco, but could improve yield and quality, fertilizer contribution rate and fertilizer agronomic utilization rate. In 2019, the yield of T3 was 7% higher than that of T2, the output value was 11% higher than that of T2, the fertilizer contribution rate was 5.1 percentage points higher than that of T2, and the fertilizer agronomic utilization rate was 53.8% higher than that of T2. In 2020, the yield of T3 was 7.2% higher than that of T2, the output value was 8.5% higher than that of T2, the fertilizer contribution rate was 4.9 percentage points higher than that of T2, and the fertilizer agronomic utilization rate was 43.9% higher than that of T2. The grey correlation analysis method was used to comprehensively evaluate chemical constituents of the middle and the upper leaves, then tobacco leaves of the three treatments were sorted. The order of middle leaves was T3> T1> T2, and the order of upper leaves was T3> T2> T1. The results of the two-year field experiment in this study showed that, compared with the conventional recommended fertilization, fertilization system of nutrient critical value for optimum yield of tobacco comprehensively and significantly improved the growth, yield and quality, economic benefit and fertilizer utilization rate of flue-cured tobacco, which could achieve the goal of precise fertilization and provide a practical way for the fertilization management in flue-cured tobacco production.