为探索贺州市烤烟K326适宜的施氮量,研究了不同施氮量对烤烟农艺性状、经济性状、外观质量、化学成分和评吸质量的影响.结果表明:随着施氮量的增加,株高、叶片数、最大叶长、最大叶宽和最大叶面积均呈逐渐增加的趋势,烟叶产量逐渐增加,上中等烟比例逐渐降低,烟叶产值、均价及上等烟比例均呈先增加后降低的趋势;施氮量偏低会导致中部叶颜色偏浅、身份变薄、油分减少,施氮量偏高会导致上部叶颜色偏暗、成熟度降低、身份变厚、结构僵硬;烟叶总糖、还原糖、淀粉含量和糖碱比逐渐降低,总植物碱和总氮含量逐渐升高,钾、氯含量及氮碱比、还原糖与总糖比变化不明显;施氮量偏低会造成中部叶香气质差、香气量不足,施氮量偏高会造成上部叶杂气重、刺激性过大.综合分析,贺州市种植烤烟K326的适宜施氮量为165 kg/hm2.

为探索贺州K326品种烤烟合理的打顶方式,研究了常规打顶、打叶留茎和打叶留花三种不同处理方式对烟叶物理特性、化学成分和经济指标的影响.结果表明:与常规打顶相比,打叶留花显著降低了中上部叶的单叶重、叶片厚度、叶面密度;打叶留茎显著降低了上部叶的单叶重及叶片厚度和中部叶叶面密度.打叶留花上部叶的总糖、还原糖及钾含量显著高于常规打顶,而总氮及烟碱含量显著降低;其中部叶的总糖、还原糖、总氮及烟碱含量均显著低于常规打顶.打叶留茎的中上部叶的化学成分与常规打顶相比差异不显著.打叶留花的产量显著低于常规打顶,但其上等烟比例显著增加;打叶留茎的产值、上等烟比例及均价均显著高于常规打顶.由此可见,打叶留花在一定程度上改善了K326的物理特性和化学成分,但导致其产量显著降低,打叶留茎在改善物理特性和化学成分的基础上显著提高了产值、上等烟比例及均价,并且未造成产量显著降低,贺州植烟生态区建议采用打叶留茎来提高烟叶质量.

【Objective】In order to provide references for exploring the suitable application amount of organic and inorganic compound fertilizer for flue-cured tobacco K326 in dry land of Hezhou tobacco-growing area, the application amounts of different organic and inorganic compound fertilizer for flue-cured tobacco were compared.【Method】Taking fluecured tobacco variety K326 as experimental material, with conventional fertilization as control (CK), experiments were carried out in Fuchuan, Hezhou in 2021 to analyze the effects of different application amounts (1 500 kg/hm2, 1 725 kg/hm2, 1 950 kg/hm2)of organic and inorganic compound fertilizer for flue-cured tobacco on the yield and quality of K326.【Result】The yield and average single leaf weight of tobacco leaf increased with the increase of N application rate, and the output value of tobacco leaf and the proportion of superior tobacco were the highest under 1 950 kg/hm2 treatment.The nicotine content in the middle leaves was in the appropriate range under the treatments of 1 500 kg/hm2, 1 725 kg/hm2 and 1 950 kg/hm2, while the nicotine content in CK leaves was higher.The chemical composition coordination of the middle leaves was showed as: 1 500 kg/hm2 treatment > 1 725 kg/hm2 treatment > 1 950 kg/hm2 treatment > CK, and that of the upper leaves was showed as: 1 500 kg/hm2 treatment > 1 950 kg/hm2 > 1 725 kg/hm2 treatment=CK, and the overall composition coordination was the best under 1 500 kg/hm2treatment.The physical properties of the middle leaves ranked as: 1 500 kg/hm2 treatment > 1 950 kg/hm2 treatment > 1 725kg/hm2 treatment > CK and that of the upper leaves ranked as: 1 500 kg/hm2 treatment=1 725 kg/hm2 treatment=1950 kg/hm2treatment > CK.The sensory quality was better under the treatments of 1 500 kg/hm2 and 1 725 kg/hm2, which showed better aroma quality and sufficient aroma volume, and the irritation of the middle leaves was obviously less.The treatment of 1 725kg/hm2 got the highest score in comprehensive evaluation.【Conclusion】In Hezhou tobacco-growing area, the yield and quality of tobacco leaves were better when the application amount of organic and inorganic compound fertilizer for K326 fluecured tobacco was about 1 725 kg/hm2.