基于偏最小二乘法的山白兰叶面积分析及测定方法的研究

目的]建立合理准确的叶面积测定方法，为山白兰的栽培管理，科研与生产实践提供理论依据。方法]以2年生山白兰叶片为材料，对其叶长、叶宽、叶长×叶宽与叶面积的关系以及5种不同方法测定叶面积进行了比较研究，并进行了聚类分析。结果]叶长、叶宽、叶长×叶宽与叶面积均呈高度的正相关性，相关系数分别为0．851、0．844和0．987，且各回归方程差异均达极显著水平，但以叶长×叶宽与叶面积的回归方程S=0．644LIV＋1．175拟合得最好；5种不同方法测定叶面积之间有极显著差异，测定结果的精确性从高到低依次为图像处理法、求积仪法、回归方程法、纸称重法和打孔称重法；叶面积聚类分析可把5种不同方法分为2类。结论]综合考虑到非破坏性取样及野外直接操作等因素，认为最佳测定山白兰叶面积的方法是回归方程法。

Analysis and Study on the Determination Methods of Leaf Area of Paramichelia baillonii Based on Partial Least Squares

Objective] Ressonable and accurate methods of determination on leaf area of Paramichelia baillonii were established in order to provide theoretical basis for the cultivation management,study and production practice of Paramichelia baillonii.Method] The correlations between leaf area and leaf length,leaf width,leaf length×leaf width and five different methods of measuring the second year leaves of Paramichelia baillonii were analyzed and compared.Also clustering analysis was studied.Result] The relations between leaf area and leaf length,leaf width,leaf length×leaf width were positive correlation,and their correlation coefficients were 0.851,0.844 and 0.987 respectively,and their difference reached at the very significant level.However,the regression equation S=0.644 LW + 1.175 among leaf area and leaf length×leaf width were the best.The difference of leaf area was very significant when they were measured by five different methods,and the accuracy of measuring results from high to low were image processing method,planimeter method,regression equation method,paper weighing method and hole weighing method.Five different methods could be divided into two categories by cluster analysis of leaf area.conclusion] Considering the non-destructive sampling and direct operations in the field and other factors,the best method of determination on leaf area of Paramichelia baillonii is the regression equation method.