Research On Responses And Degradation Of Reed-arbuscular Mycorrhizal Fungi Symbiont System For Atrazine

Atrazine is a commonly used broad-spectrum herbicide for agriculture, although it’s low toxic, because of long-time large use, and stable structure against degradation which leads to long residence time, and as a environmental hormone and potential carcinogens, it has become a serious threat to environmental safety. Abscular Mycorrhizal Fungi is a common endomycorrhiza, mycelium can invade a plant cell,forming a symbiotic system. Currently, using arbuscular mycorrhizal fungi-plant complex system to repair pollutants has become a promising technology for ecological restoration, because of advantages such as low cost, high efficiency, environmentally friendly, safe and no secondary pollution.In this paper, we use reed as test plant, atrazine as research object for pot experiment, inoculating Glomus Mosseae(AM+) before planting, with no inoculation as control(AM-) and study the repair of atrazine in wetlands using water potted method.After 25 days, the results showed that most atrazine has been degraded, and the change of degradation rate over time slowed down after showing trends. Degradation rate of different atrazine concentration is not the same, which is the highest at 0.1mg/L. AM Fungi makes a better degradation effect than AM-, whose average degradation rate of atrazine is 13.83% higher than AM- on average with each concentration.By applying AM fungi in culture matrix before planting, AM fungi colonization of reeds can reach 17.67% under appropriate conditions, mycorrhizal dependency index can reach 342%. Plants of AM+ is 27.88% higher in height, 45.50% longer in root length, 192% and 221% heavier in biomass aboveground and underground than AM-.After inoculation with AM fungi, photosynthesis of reeds is significantly enhanced,chloroplast content in leaves is increased. Under duress of atrazine, AM fungi can effectively protect reeds, it can expand the stress tolerance threshold of reeds on atrazine( ≤ 1mg/L),and can significantly improve the resilience of plants in the effective threshold. Peroxidase activity was significantly improved in plant roots, MDA content was decreased. AMF inoculation can also effectively improve the vitality of the soil matrix urease.Reed plant has low enrichment capability of atrazine, initial addition of atrazine is mainly degraded through various channels such as substitution reaction, decomposition reaction and oxidation Reaction. After the application of AM fungi, metabolic pathways of atrazine become different from the control group, but the two groups will deal with the resulting major degradation product of melamine diethyl amide(C3N5OH5), it is likely to be the different types or different reaction rates reaction leading to the differentdegradation rate. After symbiosis of AM fungi and reed was constituted, the indicators of plant growth and physiological, resilience and ability to degrade atrazine has been greatly improved. Therefore, the use of microorganisms- plant symbiosis for pollutants eestoration has high availability, and the application prospect of this technology is very considerable.