| Ornamental crabapple is widely used perennial woody horticultural plants.In this thesis,the previous researches on new variety breeding,variety characteristics and application of ornamental crabapple in China in recent years were summarized.At the same time,the phenotypic characters and molecular genetic characteristics of78 single progeny of Malus ’Sugar Tyme’ in horticultural experimental station of Hebei Normal University of Science and Technology were investigated and analyzed.Five excellent individual plants with outstanding phenotypic traits,strong comprehensive ornamental and special traits were selected by integration method and special degree of phenotypic traits.The optimal primers were used to amplify the DNA of the extracted plants by PCR,and the fingerprint was obtained by gel electrophoresis imaging.The results showed that the molecular genetic diversity of 78 single progeny and superior single plants was prominent.The main research results were as follows:The 78 tested offspring of Malus ’Sugar Tyme’ were mostly green in leaf color,with ovate and oval leaves,with more sharp teeth and sharp tips.In the fruit samples that were collected,the fruit color was mostly bright orange red,the fruit shape was mostly spherical.The shape of the tree is mainly spread,with No.78 as column shape and No.18 as droop shape.The flowers are mostly white,with more oval and long oval petals,one of which is linear.According to the ornamental value of each phenotypic index,a comprehensive evaluation score system of phenotypic ornamental value was constructed by integral method,and the phenotypic ornamental value was screened and evaluated.Finally,five excellent individual plants(W18,W8,W25,W64,W78)were selected.Their comprehensive ornamental value was relatively high,and they could be used as good breeding materials for new varieties of ornamental crapapple.And the phenotypic index of each individual plant was analyzed by cluster analysis,and the population correlation characteristics were obtained.The improved CTAB method was used to extract DNA from the leaves of 78 individual offspring plants,and the appropriate primers were selected by screening and referring to relevant literature.The gel imaging analysis of 78 DNA samples was conducted by SSR molecular marker method,including the amplification results of each selected primer and the genetic diversity analysis of each individual plant gene.At the same time,the fingerprint was constructed.The genetic diversity of the progeny population was demonstrated at the molecular level,and the gene specificity of five excellent individual plants was identified.The results provide reference for breeding new varieties of ornamental crabapple and study of ornamental characteristics application. |
