Abstract:

【Objective】 The phylogeny and genetic relationships of Chinese Ziziphus’s germplasm resources were studied at molecular levels for providing new molecular evidences of classification, protection and utilization of germplasm resources of Ziziphus. 【Method】 The sequence-related amplified polymorphism (SRAP) was assessed to analyze the genetic relationships among 14 species of Ziziphus, 11 cultivars of Z. jujuba Mill. and one outgroup. 【Result】 A total of 580 DNA bands were amplified by 19 selective primers, 570 of which (98.28%) were polymorphic. The average number of polymorphic DNA bands amplified by each primer was 30. The genetic similarities of 26 materials ranged at 0.22 to 0.99. UPGMA method cluster analysis showed that 26 materials were classified into six cluster groups with the genetic similarity of 0.38. 【Conclusion】 The results showed that SRAP technique is efficient in studying genetic relationships among Ziziphus. Z. jujuba Mill. and Z. acidojujuba C. Y. Cheng et M. J. Liu should be treated as a species, and further infraspecific classification of Z. jujuba Mill. should be classified into two subspecies. The scientific names of new taxa (Chinese jujube and wild jujube) were Ziziphus jujuba Mill. subsp. jujuba and Ziziphus jujuba Mill. subsp. spinosa (Bunge) J.Y. Peng, X.Y. Li et L.Li respectively. Z. xiangchengensis Y. L.Chen et P. K.Chou, Z. montana W.W. Smith and Z. mairei Dode may originate from same ancestry Z. xiangchengensis Y. L. Chen et P. K. Chou and Z. montana W.W. Smith should be treated as a species. The infraspecific taxon of Z. jujuba Mill. is not suitable to set up varieties.

Key words: Ziziphus Mill., genetic relationships, SRAP, cluster analysis