title: Interspecific hybridization, polyploidization, and backcross of Brassica oleracea var. alboglabra with B. rapa var. purpurea morphologically recapitulate the evolution of Brassica vegetables.
abstract: Brassica oleracea and B. rapa are two important vegetable crops. Both are composed of dozens of subspecies encompassing hundreds of varieties and cultivars. Synthetic B. napus with these two plants has been used extensively as a research model for the investigation of allopolyploid evolution. However, the mechanism underlying the explosive evolution of hundreds of varieties of B. oleracea and B. rapa within a short period is poorly understood. In the present study, interspecific hybridization between B. oleracea var. alboglabra and B. rapa var. purpurea was performed. The backcross progeny displayed extensive morphological variation, including some individuals that phenocopied subspecies other than their progenitors. Numerous interesting novel phenotypes and mutants were identified among the backcross progeny. The chromosomal recombination between the A and C genomes and the chromosomal asymmetric segregation were revealed using Simple Sequence Repeats (SSR) markers. These findings provide direct evidence in support of the hypothesis that interspecific hybridization and backcrossing have played roles in the evolution of the vast variety of vegetables among these species and suggest that combination of interspecific hybridization and backcrossing may facilitate the development of new mutants and novel phenotypes for both basic research and the breeding of new vegetable crops.
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Tongjin
authors.initials: T
authors.lastname: Liu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Xixiang
authors.initials: X
authors.lastname: Li
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Mengmeng
authors.initials: M
authors.lastname: Duan
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Jinglei
authors.initials: J
authors.lastname: Wang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Qiu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Haiping
authors.initials: H
authors.lastname: Wang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Jiangping
authors.initials: J
authors.lastname: Song
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences; Key Laboratory of Biology and Genetic Improvement of Horticultural Crops, Ministry of Agriculture, Beijing, 100081, China.
authors.forename: Di
authors.initials: D
authors.lastname: Shen
mesh_terms: D005075:Biological Evolution; D001937:Brassica / Q000235:genetics*; D016000:Cluster Analysis; D003433:Crosses, Genetic; D018745:Genome, Plant; D006824:Hybridization, Genetic; D054643:INDEL Mutation; D018895:Microsatellite Repeats; D009154:Mutation; D010641:Phenotype; D011123:Polyploidy; D019655:Quantitative Trait, Heritable; D011995:Recombination, Genetic; D014675:Vegetables