Inheritance Study On Phenotypic Traits And Fruit Quality Of Hybrid F1 Offsprings Of ‘Gala’ And ‘Mato 1’

The phenotypic traits,physiological characteristics,fruit appearance quality and internal quality of 77 F1 superior strains and their parents were investigated and measured by using the leaves,flowers and fruits as the experimental materials.These indicators were comprehensively evaluated to explore the relevant inheritance of F1 offsprings and their parents.The results of this study can provide a theoretical basis for parents selection and excellent cultivars selection in apple breeding process.The results showed as follows.1.The leaf area,leaf length and leaf width of the F1 offsprings were lower than the low parents rate from 64.58%to 93.10%,both of which were recession and negative transgressive parents inheritance.The F1 offsprings tended to be small leaf type,and the heritability of leaf area and leaf width was weak.Leaf stem length and width were recessive and mid-parents inheritance.Except that the number of flowers per inflorescence was more than 90%of positive transgressive inheritance,which was enhanced inheritance.the flower ship index of F1offsprings was mid-parents inheritance and negative transgressive inheritance.2.Mid-parent value of intercellular CO₂concentration,net photosynthetic rate,stomatal conductance and water use efficiency of F1 offsprings were lower than the mean value of those index of F1 offsprings,showing an enhanced genetic trend,and the mid-parent value of transpiration rate was higher than the mean value of F1 offsprings’,showing a declining genetic trend.Except that the transgressive rate of transpiration rate was lower than that of low parents’rate,the positive transgressive rate of intercellular concentration,net photosynthetic rate,stomatal conductance and water use efficiency of F1 offsprings were from 43.75%to 75.86%,which were higher than those of low parents rate.3.The single fruit weight,transverse and longitudinal diameter of the F1 offsprings were lower than the low parents rate（48.28%-70.83%）,which were low parents inheritance,with strong heritability and tendency to small fruit inheritance.The ratio of numerical value of fruit stem length and fruit stem diameter was the largest between the two parents,which tended to be mid-parents inheritance.The heritability of titratable acid content,soluble sugar content,soluble solids content and vitamin C content in the fruit of F1 offsprings were strong,and the genetic transmission ability of total phenol content of F1 offsprings fruits were weak.The titratable acid content,soluble sugar content,total phenol content and vitamin C content of F1 offsprings fruits were negative transgressive inheritance,and the soluble solids content was positive transgressiv--e inheritance.4.The determination results of fruit carbohydrates components showed that the sucrose content of reciprocal hybrid F1 offsprings fruits,glucose content and fructose content of orthogonal hybrid F1 offsprings fruits were enhanced and positive transgressive inheritance.The sorbitol content of reciprocal hybrid F1 offsprings fruits and the glucose content of reverse hybrid F1 offsprings fruits were recession and mid-parents inheritance.The fructose content of reverse hybrid F1 offsprings fruits was recession and negative low-parents inheritance.All four sugar components have strong heritability.The determination results of fruit acids components showed that the oxalic acid,malic acid,tartaric acid,succinic acid and citric acid of mid-parents values were greater than the mean value of F1 offsprings,which were recession inheritance.The lower-parents rates of five acids components of reciprocal hybrid F1 offsprings ranged from73.33%to 100.00%,which were negative transgressive inheritance.Except for the strong heritability of oxalic acid content of orthogonal hybrid F1 offsprings fruits,the heritability of other acid contents were weak.5.The determination results of fruit phenols components showed that the chlorogenic acid content and phloridzin content of orthogonal hybrid F1 offsprings fruits were enhanced and mid-parents inheritance.The rutin content of reciprocal hybrid F1 offsprings fruits,chlorogenic acid and catechin content of reverse hybrid F1 offsprings fruits were recession and mid-parents inheritance.The catechin content and epicatechin content of orthogonal hybrid F1 offsprings fruits were recession and negative transgressive inheritance.The epicatechin content of reverse hybrid F1 offsprings fruits was recession and positive transgressive inheritance,and the phloridzin content of reverse hybrid F1 offsprings fruits was centralized and negative transgressive inheritance.The heritability of the five phenolic contents were 84.46%-103.76%,and the heritability was strong.6.Through the principal component analysis of fruit weight,transverse diameter,longitudinal diameter,titratable acid content,soluble sugar content,soluble solids content,total phenol content and vitamin C content of F1 offsprings,four principal components with a cumulative contribution rate of 77.769%were selected,and the comprehensive scores of each strain were calculated according to the initial eigenvalue and principal component coefficient.Among the 77 strains,the highest score was 19-31 with a score of 2.208,and the fruit quality was the best.The strains with the score greater than 1 were 19-31,30-45,44-19,41-30,29-52,31-50,31-43,16-23,19-40,and the fruit quality were better.7.Through cluster analysis,the fruits F1 offsprings and their parents were divided into five categories according to the basic nutritional quality by 10 distances.The first category had small fruit weight and high total phenol content,including 47 strains such as strain 2-5 and 2-7;the second type has small fruit weight,high soluble sugar content and total phenol content,including 8 strains such as strain 2-2,8-35;the third category of fruit weight,sugar content,acid content,solid content,total phenol content,vitamin C content were low,including 21 strains such as 3-35,3-45;the fourth category had the highest fruit weight,higher titratable acid content and soluble solid content,lower soluble sugar content and total phenol content,and the highest vitamin C content,with 30-45 and 44-19 strains.The fifth type of single fruit weight,high total phenol content,there is a strain 19-31.According to the results of cluster analysis,five F1 strains had similar basic nutritional quality of Gala traits were 10-37,16-1,24-42,44-51,50-25.Among them,three orthogonal F1 strains 10-37,16-1,24-42 were biased on female parents inheritance,and the other two reverse F1 strains 44-51,50-25 were biased on male parents inheritance.Two F1 strains with similar traits of Mato 1 were 23-46 and 33-20.The orthogonal F1 strain 23-46 was biased on the male parents,and the reverse F1 strains 33-20 was biased on the female parents.