Studies On Fusant's Survivity Of Coupling System In Corchorus. Capsulari Rhizosphere And Effect On Plant's System

Polycyclic aromatic hydrocarbons (PAHs) are a important class of organic contaminants due to their toxicity and frequent occurrence at sites contaminated by coal byproducts and petroleum fractions. PAHs are not uniformly distributed with in the soil profile but show pronounced concentration gradients. The remediation of contaminated soil includes physical, chemical and biological ways. But the bioremediation have got increasingly attention because of low costs and effective.The bacteria used in this research include three groups of bacteria: (a) one which can produce biosurfactants labeled as P. aeruginosa/EGFP, (b) one which can degrade anthracene rapidly referred to as ETAN315 and (c) one is referred as Tu-1A which was isolated in Corchorus capsulari rhizosphere grown on the anthracene contaminated soil. P7.50 and ETAN315 were transformed to produce green fluorescence protein(GFP) for the detection of their growth on agar plate.Two recombinant bacteria, namely Tu-P (P_7-50 + Tu-1A) and Tu-An ( Tu-1A + ETAN315), were constructed by protoplast electric fusion. We colonized ETAN315, P. aeruginosa/EGFP Tu-P, Tu-An in rhizosphere of Corchorus capsulari to construct a coupling system for degrading contaminant.1. The electrofusion of new combinant were studied for appropriate conditioa The result was 500kHz, 45V/cm for AC field and 450V/cm, 5us, 2 nops for DC field. The resistant plate with karnarmicin and chloramphenicol could screen the fusants of Tu-P and Tu-An. The new fusants had the ability to produce apparent fluorescence under UV light.2. The colonization effect of different introduced bacterial were investigated and the result showed: (a) EGFP was a appropriate technology to study microbial activity in soil. After 35 days the bacterial labeled by EGFP also could be detected from other microbial under UV light; (b) the population of Tu-P and Tu-An id more than P7.50 and ETAN315, in the 35 days, the number of fusants' survival always approached 10⁶cells/g soil. In all five contaminated concentrations, these facts were shown the same.3. We compared two kinds of phytoremediation: transplant and semination, and we foundsemination is a better way. When the pollution's concentration is 300mg/kg, the survival rate of transplant was only 60%, but the survival rate of semination was 92.5%. We also study the averge change of plant height, the result appeared that the treatment of fusants was better than the treatment of non-bacteria. At the measurement of aboveground biomass at 42d, the disparity of different treatment was great: the a-p treatment is 4.36-10.91 times than the non-bacteria treatment.