Expression Of Yeast Copper Resistant Gene In Pseudomonas Fluorescens And The Effects Of Recombined Strain On The Absorption Of Soil Copper By Carrot Seedling

l.The CUPI gene about 200bp was cloned and the SD sequence AGGAGG was added in llic upstream of it by PCR. Sequencing results showed that the PCR product was correct. The CUI'l gcno then was constructed into a wide-range-host cosmid pLAFR3, and transformed into AS1.13K1 (pseudomonas fluorescens} strain, the recombined strain was named AS1.1381/pLAFR3CUPI. Study showed that the AS1.1381/pLAFR3CUPI had higher copper resistance (6mM Cu2+) than the wide strain AS1.1381/pLAFR3(4.5mM Cu2t).Z.Colonizalion lest of p.f demonstrated, ASl.l381/pLAFR3CUPI and AS1.1381/pLAFR3 had similar capability of colonization around the carrot roots; The colonization density in different location was rhizoplane>rhizosphere; Compared with different inoculation ways, the colonization ability in rhizoplane was seed inoculation better than soil inoculation, but colonization in rhizospherc was quilc the contrary; In 30 days after inoculation, the colonization density decreased gradually; Under the stress of excessive soil copper, AS1.1381/pLAFR3CUPI had belter ability of colonization Ilian ASl.l38l/pLAFR3and could colonized in soil with higher copper concentration.3.1n soil treated with l~7mmolCu2VKg soil, AS1.1381/pLAFR3CUPI could reduce the absorption of copper by carrot, and lightened the inhibition to the growth of carrot by excessive copper in plant, while AS1.1381/pLAFR3 had this ability only in soil applied with 1~5 mmolCu2+/Kg soil. Under same copper concentration treatment, the ability of reduction of copper toxicity and growth promotion to carrot plant was AS1.138l/pLAFR3CUPI> AS1.1381/pLAFR3.