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Azo dyes because of ease of synthesis, stability, color, variety, etc. are widely used in printing and dyeing, chemical industry, accounting for over 80% of the dye species. While some coastal printing and dyeing, chemical and other companies will be directly used for industrial production of sea water, resulting in a large number of salt azo dyes wastewater generation. Azo pollution has become increasingly serious environmental problems. Among the many azo dye wastewater treatment technology, the plant - microbial remediation its low cost, good effect, can be in-situ remediation and other advantages, more and more people's attention. This paper first examines the salt-tolerant bacteria GTY in 5% NaCl concentration on Azo Golden G, acid red GR and Acid Red B decolorization. GTY found the three azo dyes decolorization efficiency descending order: Acid Red B, acid red GR, acidic golden G. GTY better bleaching under anaerobic conditions, the high oxygen bleaching effect will be severely inhibited, but in the condition of trace oxygen (DO value of about 1.80), has little effect on the bleaching GTY, and this dissolved oxygen concentration of the normal growth of the plants can . NaCl and then examines the three dyes on alfalfa, Sesbania, Salicornia and Suaeda salsa seed germination, experimental results show that alfalfa and Sesbania of azo dyes are well tolerated, but Salt tolerance is poor; Salicornia and salsa to NaCl was well tolerated, but poor tolerance of azo dyes. According to the characteristics of four plant were investigated under different conditions decolorization. At 5 g / L NaCl concentration, alfalfa 100,500,1000 mg / L azo dyes decolorization rates were 70%, 50%, 30%; Sesbania decolorization rate of approximately: 30%, 22% , 9%. After adding GTY, alfalfa 100,500,1000 mg / L azo dyes decolorization rate increased by about 10%, 7%, 5%; Sesbania decolorization rate increased approximately: 35%, 20%, 15% . At 15 g / LNaCl concentration, Salicornia and salsa on 100 mg / L acidity and acid red GR Golden G decolorization rate of around 10%, the decolorization rate of Acid Red B in 25% to 45%. After adding GTY, Salicornia decolorization rate of azo dyes increased by about 33%; salsa for azo dyes decolorization rate increased by about 39%. And salsa and Salicornia part decolorization rate increased more than GTY decolorization of azo dyes alone, indicating that between plants and microbes have some mutual promotion effect. Extracted four plant root exudates, find root exudates on growth GTY all have a certain role in promoting and root exudates the more the greater the growth-promoting effects on GTY, thus indirectly improving their ability decolorization of azo dyes .
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