Cloning And Preliminary Characterization Of MsAp₂ Gene From Alfalfa （Medicago Sativa.L）

Alfalfa（Medicago sativa.L）is leguminous grass plant,which is rich in nutrients,especially high in protein content,and has the functions of soil and water conservation and soil restoration.The expanded development of animal husbandry and prataculture has higher requirements on the yield and quality of alfalfa.Cultivating new varieties of alfalfa with good traits and high yield plays an important role in the development of forage industry and animal husbandry and the construction of ecological environment.In this experimental,alfalfa was used as experimental material,the MsAP₂gene of alfalfa was obtained by RT-PCR,and the 3302-3flag-AP₂plant expression vector was constructed by DNA recombination technology,which was introduced into alfalfa by Agrobacterium-mediated transgenic method.the regeneration plants of alfalfa were obtained through the processes of callus induction,differentiation,rooting,seedling hardening and seedling transplantation,in which the callus induction rate was 50%and the bud formation rate was 40%,and finally obtained plants with MsAP₂gene transferred.Phenotypic analysis of transgenic plants showed that compared with wild type,the growth and development of transgenic plants were inhibited,and the phenomenon of premature senescence generally appeared.Plant height shows the difference phenomenon,the number of branches changed,the size and shape of leaves changed,root growth and development are inhibited.By measuring endogenous hormones,it was found that the content of abscisic acid and auxin of transgenic plants showed an upward trend.The content of zeatin decreased,while the content of gibberellin showed a downward trend.Compared with wild type,the size,shape and arrangement of leaf epidermal cells of transgenic plants changed significantly.Preliminary analysis showed that MsAP₂gene played a regulatory role in morphogenesis,hormone level and growth and development process of alfalfa.In this experiment,the function of MsAP₂gene in alfalfa was preliminarily explored,which provided experimental materials and theoretical reference for further exploring the function of MsAP₂gene in alfalfa.