Abstract:

The study aims to investigate and identify feasible mathematical analysis methods to provide a reference for the quality evaluation of gray jujubes in Xinjiang. In this study, gray jujube fruits subjected to a compound treatment with four agents being used as test materials, and 12 fruit quality indicators were comprehensively analyzed using factor analysis, entropy value method and level-gray relation analysis, respectively. The results showed that there were different degrees of variability among the fruit traits, ranging from 1.56% to 37.58%. Among them, the coefficients of variation of single fruit weight and single plant yield were large (>10%), whereas the coefficients of variation of the remaining indicators were relatively small (<10%). The results of factor analysis demonstrated that the 12 quality indicators of the gray jujube were converted into three common factors, each with eigenvalues greater than 1. The cumulative variance contribution rate was 89.974%, which encompassed the majority of the information regarding the participating gray jujube fruit traits. Moreover, the results of the composite scores demonstrated that the comprehensive evaluation of fruit quality was highest after T₂ treatment (0.25 mmol/L SA+ 30 mg/L DA-6+ 0.01 g/L BR). The results of the entropy value method indicated that the coefficients of variation for the trait indices exceeded 10% in all cases, with the exception of four indices of longitudinal fruit diameter, fruit shape index, single fruit weight, and organic acid. Among these, the weight of fructose was the highest at 14.83%, followed by vitamin C, while the weight of transverse fruit diameter was the lowest, and the ranking of the scores revealed that the comprehensive quality of gray jujube was best after T₁ treatment (0.25 mmol/L SA+ 30 mg/L DA-6). The results of the level-gray relation analysis indicated that single fruit weight and single fruit yield had the highest weights, while organic acid and cellulose exhibited the lowest weights. Furthermore, the scoring results demonstrated that the integrated quality of gray jujube was optimal following the T₂ treatment. In evaluating the quality of gray jujube, the extensive data on fruit trait indices will lead the limited variation in key indices. Combined with the production performance of different treatments, the evaluation results of hierarchical-gray correlation degree are more in line with the actual situation.

Key words: grey jujube, fruit quality, factor analysis, entropy method, multi-level gray relation analysis, quality evaluation