Establishment of Quality Evaluation Model of Phalaenopsis Based on Principal Component Analysis

The 42 Phalaenopsis samples were used as experimental materials and determined 22 morphological indices included plant size, leaf length, leaf width and other traits.The methods of descriptive statistical analysis, correlation analysis, principal component analysis and regression analysis were conducted to analyze and evaluate, and then the quality evaluation model was created, in order to provide reference for the high quality development of Phalaenopsis industry.The results showed that there were differences in 22 morphological indices among different cultivars, and the degree of dispersion was variation.The range of the coefficient of variance was from 16.12% to 68.73%.Correlation analysis showed that there were positive or negative correlation among the 22 indicators.Five principal components were obtained with a cumulative contribution rate of 88.242% after principal component analysis.The comprensive scores could well distinguish the quality differences between different samples.Finally, the quality evaluation prediction model of Phalaenopsis was established by the stepwise regression analysis as follows, Y=-10.109+1.331X₁₆+0.017X₁₃+0.030X₅+0.058X₂+0.163X₆+0.609X₂₂-0.014X₁₉,in which petal length, the L^* of middle sepal, peduncle length, leaf length, peduncle diameter, the middle lobe width of labial flap and the a^* of petal are important indicators for evaluating its quality.