Remediation of phenanthrene phytotoxicity by the interaction of rice and endophytic fungus P. liquidambaris in practice.

Phenanthrene cannot be effectively degraded in the agricultural production systems and it is greatly hazardous for food safety and human health. In our study, the remediation ability and mechanism of rice and endophytic fungus Phomopsis liquidambaris interaction on phenanthrene in the rice-growing environment were explored using laboratory and pot experiments. The results showed that plant-endophyte interaction had the potential to enhance remediation on phenanthrene contamination in the rice-growing environment. The content of phenanthrene in soil and rice (including leaves, roots, and grains) of the plant-endophyte interaction system was about 42% and 27% lower than of the non-inoculated treatment under 100 mg kg treatment. The mechanism may be related to the improvement of plant growth, root activity, chlorophyll content, ATP energy supply, and antagonistic ability of rice to promote the absorption of phenanthrene in the rice-growing environment, and then the phenanthrene absorbed into the rice was degraded by improving the phenanthrene degrading enzyme activities and gene relative expression levels of P. liquidambaris during plant-endophyte interaction. Moreover, the plant-endophyte interaction system could also promote rice growth and increase rice yield by over 20% more than the control under 50 mg kg treatment. This study indicated a promising potential of the plant-endophyte interaction system for pollution remediation in agriculture.