Image Analysis And SSR Markers For Identification Of Rose Varieties

Identification of Rosa chinensis new varieties was studied in this paper.Digital images were used for the anlysis of leaf traits and variety identification of rose varieties with similar leaf morphology or close genetic relationships.At the meantime,leaf traits appropriate for DUS testing were screened.The technique of digital image analysis was also used to comapare flowers of two sets of rose varieties,emphasized on petal color.Identification of 12 rose varieties wasstudied with use of SSR markers.The objective was to explore new motheds which can be used for rose variety identification.Results were summarized as the followings:1,Image analysis was used in identification of 4 rose varieties with similar leaf morphology.Each leaf was described using 16 morphological traits.One-way ANOVA,factor analysis a nd discriminant analysis were used to distinguish the rose varieties.The results indicated that there were significant morphological differences among the 4 varieties.And 5 among the 16 measured morphological traits were more independent.Fisher's discriminant models were developed with 9 significantly contributing morphological traits.For each variety, the accuracy of identification was 96.9%.The results confirmed that morphological traits may be successfully employed in image analysis for preliminary identification of rose varieties.2,10 closely related rose varieties were also described with 16 leaf morphological traits by digital image analysis.Results of one-way ANOVA indicated that there were significant morphological differences among the 10 varieties.Multiple comparisons indicated that the width of leaf teeth,the area ratio of blade to petiole and the form coefficient were good in uniformity and genetic stability,and less influenced by the environment.The accuracy of the Fisher's discriminance was 73.5%.'Peace' and its mutation variety 'Flaming Peace' were very similar in leafmorphology,only the 'form coefficient' showed significant different,and each of the rate of incorrect identification was up to 50%and 80%.Except for the accuracy of variety identification of'Chun Yu','Eden Rose' was 100%,the six varieties were miss identified to other wrong varieties,it indicated that even with environmental influence,the genetically related rose varieties still had some similarities.3,Mutation rates of all the flower morphological traits of the bicolor rose varieties were less than 6%,which showed excellent uniformity.The largest mutation rates were concentrateded in 'petal lenth','petal width','petal area','petal perimeter','petal aspect ratio' and 'form coefficient',ranging from 0.1%-6.0%.These 6 traits were all closely related to petal size,in contrast,the flower color traits proved to be good in uniformity.The rate of correct identification was 85%.4,Mutation rates of the flower traits 'petal lenth','petal width','petal area','petal perimeter','petal aspect ratio'and 'form coefficient' of the blending-color varieties were just similar to the rates of the bicolor varieties,ranging from 0.1%- 5.0%.Except for the 'saturation' of the petal's main color on inner side of'Eiko',the largest mutation rates were observed in 'H value of main color','area of main color','size of basal spot','area of the secondary color' at inner side of the petal.And,most tested varieties showed considerable mutation rates in these 4 traits.It was worth noting that'intensity' of the petal's main color at inner side remained tremendously uniform in all varieties.Besides,the mutation rates of all other flower traits were lower than 5%.The accuracy of variety identification was 90.6%. Except 'Eiko' and 'Altasse'75',all the other 6 blending-color varieties were correctly identified.5,DNA purification process was necessary to eliminate the effect of hydroxybenzene on PCR products.2 pairs of SSR primers producing excellent polymorphism in amplified SSR sequences were selected,the percentage of polymorphism was 100%.17 rose varieties were devided into 7 groups by primer Rh72,and 8 groups by primer Rh98.Varieties 'Little Girl' and 'Parkdirektor Riggers' were distinguished by primer Rh72,and the identification of 'Compassion','Parkdirektor Riggers','Schloss Mannheim' and 'The Fairy' was sucessfully done by primer Rh98.With use of both primers,10 varieties were identified,and the other 7 varieties can not be identified but classified into 3 groups.