Study On The Adaptability Of Marchantia Polymorpha L. To Light Intensity And Transgenic AtLhca

The absorption,transfer and transformation of light energy in plant photosynthesis,that is,the light reaction of photosynthesis,is promoted by the transmembrane electron transfer of photosystem I(PSI)and photosystem II(PSII,photosystem II)excited by light.The other is the core part of the PSII system,which is responsible for receiving and transmitting the electron energy.For photosynthetic organisms with different evolutionary degrees,the structure of core complex is relatively conservative,while the composition of lhci and LHCII is variable.The spectral range of light energy used by different plants is not the same.Fundamentally,the spectral range that a plant can absorb and use is determined by the type,quantity and assembly mode of light harvesting proteins.Bryophytes often live in humid and shady environment.As the first higher plant to land,how does it adapt to strong light?What light protection mechanism does bryophyte have?What changes have taken place in the light harvesting protein composition of bryophyte photosystem I to make plants more adaptable to terrestrial life?Guided by these scientific problems,this project selects(Marchantia polymorpha L.),a model plant of moss,as the research material.The main results are as follows.(1)This paper has carried out the light intensity adaptability research on wild type liverwort.The chlorophyll fluorescence parameters and pigment content of the landlords were measured on the day of 0,3,5and 7 days,respectively,under the light intensity of 35?molm^-2s^-1(OL),100?molm^-2s^-1(ML),350?molm^-2s^-1(HL).Through the analysis of induction curve,fast light curve and Post-Illumination,it is concluded that the F_v/F_m of the local money decreased and was in stress state under high light treatment.However,the parameters of the photosynthetic activity of Y(I),Y(II),q P and other reactions remained high level,and the NPQ value decreased with the treatment time prolonged under high light,which was presumed to be the result of plant adaptation.In addition,the liverwort starts the ring electronic transmission under the high light treatment to play the role of light protection.The analysis of pigment showed that the number of Ant produced by high light induction was significantly greater than that of Zea induced by induction.It was speculated that ant led photoprotection was present in the local money,which should be verified.The accumulation of Zea and Ant in ML increased first and then decreased significantly.Under HL condition,the accumulation of Zea and Ant increased significantly,and also decreased in the later stage.This indicated that lutein cycle played an important role in light protection.Zea dependent NPQ was one of the main forms of light protection,and the high light treatment for 7 days made the liverwort produce high light adaptability.(2)In this project,the composition of PSI-LHCI light harvesting protein was studied.The At Lhca overexpression vector and Mp Lhca gene editing vector were successfully constructed,and then the transgenic experiment of diqian was explored.Through Agrobacterium transformation and resistant medium screening,diqian plants that can grow normally on resistant medium were cultivated,and then their genomes were identified,which proved the feasibility of diqian transgenic.It lays a foundation for further research on the structure and function of PSI-LHCI from the perspective of evolution.