烤烟表面微观结构特征与外观品质的关系

Relationship Between Surface Microstructure Characteristics and Appearance Quality of Flue-cured Tobacco Leaves

为明确烟叶外观品质差异的成因，进而建立烟叶外观品质的客观、量化评价方法，以河南、云南产区初烤烟叶样品为材料，采用扫描电镜和图像处理软件分析的方法，研究了烤烟表面微观结构特征指标（细胞面积、周长、形状、密度和气孔密度等）与外观品质的关系，并建立了基于表面微观结构特征指标的烤烟外观品质预测模型。结果表明：①在产地、部位一致的条件下，随烟叶成熟度的提高，细胞形状呈不规则变化趋势；叶片结构疏松程度较好的烟叶，细胞相对较小；随烟叶身份由稍薄-中等变化，气孔密度呈下降趋势，身份相对适中的烟叶细胞形状相对规则；油润感较强的烟叶，细胞相对较小，细胞密度相对较大。②利用细胞面积、细胞周长和细胞形状参数，建立了烟叶成熟度与叶片结构综合状况预测模型，建模样品和验证样品预测值与实际评价值的平均相对误差分别为3.18%和6.20%。

To clarify the factors affecting the appearance quality of flue-cured tobacco leaves and further to develop an objective and quantitative method of evaluating the appearance quality, taking tobacco leaves from Henan and Yunnan as samples, the relationship between the surface microstructure characteristic indexes （cell area, cell perimeter, cell shape, cell density and stomatal density） and appearance quality was studied with scanning electron microscope and image processing software, and a prediction model of appearance quality based on surface microstructure characteristic indexes was established. The results showed that： 1） For the leaf samples from the same growing area and stalk position, cell shape changed irregularly along with the increase of maturity; leaves with open structure had smaller cell size; stomatal density decreased with leaf body of slightly thinner to moderate, leaves with moderate body was relatively regular in cell shape; oily leaves has smaller cell size and larger cell density. 2） Taking cell area, cell perimeter and cell shape as variables, a model for predicting the state of maturity and structure of tobacco leaves was established, and the average relative errors between the predicted values and evaluated values were 3.18% and 6.20% for modeling samples and validation samples, respectively.