Abstract: Using mature leaves of two longan cultivars ‘Chuliang’ and ‘Shixia’ as materials, the correlation between leaf circumference, leaf length, leaf width, leaf length/leaf width, leaf width × leaf width, leaf length × leaf length, leaf length × leaf width and leaf area was analyzed, and nine simulated regression equations were established. The results showed that the leaf area of ‘Chuliang’ and ‘Shixia’ could be estimated by leaf circumference, leaf length, leaf width, leaf length/leaf width, leaf width × leaf width, leaf length × leaf length, leaf length × leaf width. The regression equation based on leaf length and leaf width had the highest R ², which meant the fitting effect was the best, and the correlation was the greatest. Therefore, leaf length and leaf width could be used as the preferred index for estimating longan leaf area. Among the nine regression equations based on leaf length × leaf width, the linear, quadratic, cubic and power functions could fit the relationship well, among which the power function had the highest accuracy and was more suitable for estimating the leaf area of longan. The most accurate power function equations of leaf area corresponding to ‘Chuliang’ and ‘Shixia’ were y=0.751x ^1.006 and y=0.986x ^0.973. The most suitable power function of total leaf area for two longan varieties was y=0.869x ^0.988.

Key words: Chuliang, Shixia, leaf area, regression equation, power function

摘要： 以‘储良’和‘石硖’2个龙眼品种的成熟叶为材料，对叶片的周长、长、宽、长/宽、宽×宽、长×长、长×宽等指标与叶面积的相关性进行分析，建立9种模拟回归方程。结果表明，‘储良’和‘石硖’的叶面积均可用叶片的周长、长、宽、长/宽、宽×宽、长×长、长×宽等指标进行估算，基于叶长×叶宽建立的9种叶面积回归方程R ²均最高，拟合效果最好，且相关性最大，因此叶片长×宽可作为龙眼叶面积估测的首选指标。基于叶长×宽建立的9个回归方程中，一元线性方程、二次方程、三次方程、幂函数能较好拟合，其中以幂函数估算的精度最高，较适合用来估测龙眼的叶面积。‘储良’和‘石硖’叶面积对应的较为精准的叶面积幂函数方程分别为：y = 0.751x ^1.006 和 y = 0.986x ^0.973。最适合两个龙眼品种的总叶面积幂函数方程为y=0.869x ^0.988。

关键词: 储良, 石硖, 叶面积, 回归方程, 幂函数