Phenotypic Diversity And Genetic Analysis Of F₁ Generation In Gerbera

Gerbera（Gerbera hybrida）is a perennial herbaceous and very popular among consumer because of its numerous colors,beautiful flower posture,and application forms.Gerbera is one of the most important cut and potted flower in the world market.However,with the improvement of people’s living quality,the market competition of gerbera is also increasing fierce.It became the primary target of the gerbera breeding workers to breed high ornamental and economic value of cut flower new varieties.In this study,20 gerbera resources and two F₁ populations were selected to screen 20 major ornamental traits for observation.The phenotypic diversity of 20 resources was systematically analyzed by variance analysis,correlation analysis,cluster analysis and principal component analysis.At the same time,the preliminary genetic analysis was performed on two F₁ populations to provide a reference for the breeding of new gerbera varieties.The main results of the study are as followed:1.Through the analysis of 20 ornamental traits of 20 gerbera resources,it was found that 20 gerbera resources possess strong variable traits which were the 1/3 fissure depth in the middle of leaves,petiole length,the flowering number at the same period,peduncle length,petal main color and inflorescence type.2.Correlation analysis showed that the correlation coefficient between the 13quantitative traits ranged from-0.673 to 0.941.There was a significant positive correlation between plant height and petiole length,peduncle length and leaf width.The length of peduncle was significantly positively correlated with crown width,length and width of leaves,1/3 fissure depth in the middle of leaves,and petiole length.The inflorescence diameter was significantly positively correlated with the plant height,leaf length,and width,1/3 fissure depth in the middle of leaves,petiole length,ray florets length,but significantly negative with the number of flowerings in the same period.Relationship cluster analysis showed that 20 gerbera resources could be divided into 4 different groups based on plant height,leaf width,leaf tip shape,and flower center color.3.The results of the principal component analysis showed that the cumulative contribution rate of the first seven components reached 86.567%,and the contribution rates of the seven principal components were 36.767%,13.970%,10.031%,7.987%,6.397%,6.259%and 5.156%,respectively.This indicates that the traits with the largest factor fall in the seven principal components represent most of the phenotypic trait variability.Among them,the traits that affect the phenotype of gerbera are plant height,leaf size,flower center color,outer lingual flower length,and shape.4.Genetic analysis of the two F₁ populations revealed that the crown width,peduncle length,peduncle diameter,inflorescence diameter,and number of flowering at the same period of the two groups all showed a certain degree of decline.Among the F₁ generations of’Fenyu’×’Gaoshan’,there are obvious traits with superior parental traits such as leaf width,depth of 1/3 crack in the middle of leaves,length of outer ray ray flower,and outer tongue.Flower width,flowering number at the same period and flower diameter are favorable for the screening of new varieties with wide leaves,large flowers and more flowers in the same period.In the F₁ generation of’Huoyan’x’Fenxiu’,the overall mean values of the two petal traits,petiole length and outer ray ray flower width,were slightly larger than those of the parents.The other traits were smaller than the parents and were more suitable for screening than the parent plant type.5.In the F₁ generation of the two Gerbera hybrids observed in this experiment,the flower color was widely separated,with individuals not only appearing beyond the parental color,but also individuals with complex colors and various transitional colors.The proportion of dark colors in the flower center color is higher than that in the light color.The heritability of genetically flattening in flower position is higher than that of downturning and uplifting;single-petal has a certain genetic advantage,and heritability of semi-double valve is the highest;the shape of ray florets of F₁ hybrids is separated but separated.Not obvious.