Genetic Transformation Of CmPIP1/2 In Chrysanthemum Morifolium And Salt Resistance Verification

Chrysanthemum is one of the important flowers in northern horticulture,and it has the characteristics of extensive management,dwarf plants and various colors.As a member of the MIP family,the plasma membrane intrinsic protein can regulate water balance in the plant cells,participate in the osmotic stress response and regulate the stomatal movement,and play an important role in resisting adversity stress.In order to study the function of CmPIP1 and CmPIP2,we chose six kinds of chrysanthemum,namely 'fenshaqun','jinqiu','zitao','huoyan',and 'fenjiaren',and under different NaCl concentrations,the relationship between K+/Na+ content ratio and relative expression of CmPIP1/2 in plant leaves was found.To explore the biological rhythm and tissue specificity of the 'huoyan' of chrysanthemum.Based on the overexpression and interference vectors of CmPIP1 and CmPIP2,which had been successfully constructed in the laboratory,the overexpression and interference of transgenic plants of CmPIP1 and CmPIP2 were studied,and the salt resistance of the transgenic plants was verified,which provided a strong molecule basis for the cultivation of new lines with stronger salt resistance,and enriches the planting of flowers in saline areas.1.Under 0 mmol/L?100 mmol/L?300 mmol/L?500 mmol/L NaCl stress,the salt tolerance of six kinds of chrysanthemum was from strong to weak arranged as:'fenshaqun','huoyan','fenjiaren','jinqiu','zitao'.CmPIP1/2 and the ratio of K+/Na+ content was closely related.2.In chrysanthemum 'huoyan',CmPIP1 and CmPIP2 were expressed in roots,stems,leaves,flowers and flower buds,however CmPIP1 and CmPIP2 had the highest expression in leaves.And CmPIP1 and CmPIP2 had biological rhythms.3.This experiment obtained the corresponding transgenic lines by hygromycin resistance screening,Real-Time PCR and PCR.There were 13 CmPIPl interference transgenic plants,6 CmPIP1 interference transgenic plants,5 CmPIPl overexpression transgenic plants,and 16 CmPIP1 overexpression transgenic plants.4.Under 300 mmol/L salt stress for 5 days,the CmPIPl/2 overexpressing transgenic plants were growing well,and the fresh weight reduction of CmPIP1/2 overexpression transgenic plants was less than that of wild type plants;The CmPIPl/2 interference transgenic plants and wild type plants were wilted,and the fresh weight reduction of CmPIP1/2 interference transgenic plants was the same as that of wild type plants;The root length elongation of CmPIPl/2 overexpression and interference transgenic plants was greater than that of wild type plants.Under 300 mmol/L salt stress for 3 days,the change of MDA content in CmPIP1/2 overexpressing transgenic plants was lower than that in wild type plants,and in CmPIP1/2 interference expression transgenic plants,the change of MDA content was higher compared with wild type plants.Thus,CmPIP1 and CmPIP2 are closely related to the salt resistance of chrysanthemum.CmPIP1 and CmPIP2 had stronger salt resistance in overexpressing transgenic plants.