Study On Molecular Marker Linked To Female Flower Antheses Gene Of Walnut (Juglans Regia)

As an important woody ecological species with high commercial value, walnuts are widelygrown in as many as25provinces in our country. All Juglans species are monoecious, and areheterodichogamous with male and female flowering occurring at different times. In North ofChina, walnut flowers were vulnerable to spring late frost and results in a loss of productivity.This research is focus on flowering period of walnut, so as to improve the walnuts’adaptability for extreme environmental conditions.In this research we did4years phenophase observation, and analyzed the recordedinformation. Based on the summing rules, markers linked to female flower antheses geneopening of female flower gene have been identified using bulked segregant analysis coupledwith the SRAP techniques.The main results are as follows:1. The variance analysis among different years showed significant differences amongindividuals in different years, which provide abundant materials to breeding. The research onthe female stage showed that the phonological phases happened in the same order amongindividuals in different years, which indicated that the phenology characteristic was controlledby genetic.2. A marker, Me8/Em101000, linked to female flower antheses gene has been identified usingbulked segregant analysis coupled with the SRAP techniques.3. Analyzing the specific marker segregation on adult F1seeding population showed that, a1:1segregation ratio was observed which based on the Chi-square test Χ~2(1)(0.05)=3.814),indicating the specific marker was co-separated with femal-flower-late-opening trait. Therecombination frequency of the trait was2.35%.4. By using selective genotype linkage analysis and converting recombinant frequency withHaldane function, the genetic distances between the marker and the female flower antheses locuswere2.59cM.