Transformation Of GsPPCK Gene Into Alfalfa And Alkaline Tolerance Analyais In Transgenic Plants

Abiotic stress factors such as salinity, low temperature and drought are the majorenvironmental factors that limit plant growth, development and geographical distributionand adversely affect the yield and quality of crop. This has become major problemsimpacting on agricultural production in our country and the world. The effective means topromote the development of agricultural production were breeding salinity crop varieties,and made full use of saline land resources. The alfalfa (Medicago sativa L.) as a cultivatedpasture, was bond of agriculture and animal husbandry. It was nutritious, high yield, andhad wide adaptability, strong salt resistance characteristics, could improve plant and makegood use of saline-alkali soil. Conventional breeding method to cultivate excellent newvarieties is slower, so using genetic enineering techniques to cultivate alkali-resistingmaterial to meet the growing demand for alfalfa production in China has important researchvalue and broad prospects for the development and application. Wild soybean (Glycine soja)has salt and alkaline stress-resistance and adaptive capacity. In this study, we identified twokey alkali stress-responsive serine/threonine kinase genes (GsPPCK1,GsPPCK3) from wildsoybean genomic regulatory networks profiles under alkali stress which was established inour lab previously. Two genes (GsPPCK1, GsPPCK3) were transferred into Medicagostativa Longmu806by the Agrobacterium-mediated method. After selected by0.8mg/LGlufosinate, we obtained45and52resistant lines of GsPPCK1and GsPPCK3respectively.The resuts of PCR and Real-time-PCR showed that GsPPCK1and GsPPCK3wereover-expressed in each transgenic line. In order to identify the transgenic alfalfa alkalidegree, We made a preliminary analysis of the alkali resistance and Selected200mmol/LNaHCO3as stress concentration,250mmol/L NaHCO3as lethal concentration. Aftertransgenic alfalfa GsPPCK1and GsPPCK3were stressed with0,100,200,250mmol/LNaHCO3respectively, we compared transgenic alfalfa and non-transformed alfalfa atdifferent concentrations stress by physiological indicators. between transgenic and wild-type alfalfa under alkaline stress, all those results showed that over-expression ofGsPPCK1and GsPPCK3in alfalfa enhanced plants tolerance to high alkali.For this study to establish the system of alfalfa alkali resistance transgenic molecularbreeding technology and its industrialization application,exploitation and utilization ofalkaline resources, increase the farmland area, will play a positive role.