33份火龙果种质果实性状主成分分析及综合评价OA北大核心CSTPCD

In order to understand the fruit quality of different varieties of pitaya and to screen the germplasm resources with good quality,33 pitaya germplasm resources were and 15 botanical traits and quality properties such as single fruit weight,fruit transverse and longitudinal diameters,proteins,total flavonoids,and beet pigments were measured,and fruit quality was comprehensively evaluated by using correlation analysis and principal component analysis.The 33 pitaya germplasm resources had a single fruit mass of 164.67-556.00 g,a transverse fruit diameter of 5.86-9.40 cm,a longitudinal fruit diameter of 7.29-11.94 cm,a fruit shape index of 0.99-1.39,a total sugar content of 78.80-126.05 mg/g,a total phenolic content of 0.64-2.46 mg/g,a total flavonoid content of 0.85-9.67 mg/g,hardness of 6.62-16.86 N,protein content of 0.29-1.45 mg/g,beet pigment content of 0.69-37.01 mg/100g,and starch content of 14.12-44.60 mg/g.The total acid content ranged from 0.33 to 15.23 mg/100 g.The Pearson's method was used to cor-relate the main botanical and quality traits of the pitaya germplasm resources.and quality traits were correlated.The correlation coefficients were 0.478 for total acid and soluble solids,and-0.532 for sugar-acid ratio,while the correla-tion coefficients were 0.749 and 0.942 for longitudinal and transverse diameters.The correlation coefficient between longitudinal diameter and fruit shape index was 0.426,and the correlation coefficient between weight and sugar-acid ratio and hardness was 0.360 and 0.351,respectively.After principal component analysis,the 15 traits were combined into 7 principal component factors,with a cumulative contribution of 82.55％.The first principal component contributed 22.45％,with single fruit weight,fruit longitudinal and transverse diameter,and sugar-acid ratio contributing more.The second principal component contributed 13.87％,with total sugar content,soluble solids content and starch content con-tributing more.The contribution of the third principal component was 12.28％,with soluble solids content contributing more.Among them,sugar-acid composition,single fruit weight,fruit transverse diameter,fruit longitudinal diameter,soluble solids content,starch content,amino acid content,etc.are the key indexes for evaluating the comprehensive quality of dragon fruit.After comprehensive evaluation,six excellent pitaya singles with high comprehensive scores were screened,i.e.,Reyan 1 hao,Wanhuafenhong,Hongbaolong,Wucihong,Linjiahongyun and Hongjinbao,which can be used as high-quality parents for pitaya quality breeding.