Comprehensive Evaluation of Introduction and Screening of New Cucumber Varieties Based on Principal Component Analysis

Taking the new cucumber varieties from the Cucumber Research Institute of Tianjin Academy of Agricultural Sciences as the test material, the principal component analysis method was used to study the comprehensive analysis method of the main agronomic characters of cucumber, and the growth index, quality index, photosynthetic index, yield of cucumber.The effects of 21 indicators on 12 new cucumber varieties were selected, in order to screen out new cucumber varieties suitable for planting in Shijiazhuang area.The results showed that the largest coefficient of variation was the soluble sugar content, which was 59.70%,plant height, stem diameter, leaf area, fruit length, fruit diameter, soluble solids, intercellular CO₂ concentration, and fluorescence maximum were all small, 8.44%,7.38%,9.65%,7.80%,4.87%,9.90%,3.92%,and 3.36%,respectively, all less than 10%.Correlation analysis of these 21 agronomic traits showed that each trait was extremely significantly or significantly correlated with at least 1 other trait.The yield and the chlorophyll content were extremely significantly positively correlated, indicating that the yield mainly depends on photosynthesis.Through principal component analysis, 6 principal components were obtained, which synthesized 83.825% of the original information, the function expressions and comprehensive evaluation criteria of the first 6 principal components was Y=0.296 32Y₁+0.156 39Y₂+0.147 52Y₃+0.095 09Y₄+0.080 46Y₅+0.062 46Y₆,the comprehensive score of the 12 cucumber varieties was obtained.Variety 10,that was ‘Jinyou 186’,had the highest score.Therefore, ‘Jinyou 186’ was the most suitable variety for planting in Shijiazhuang area, and the result provided cucumber growers with a reference for the introduction of new varieties of Tianjin cucumber.