%0 Journal Article %A YANG Sen %A YIN Xianhui %A HUANG Huagang %A LONG Youhua %A WU Xiaomao %A DAI Yuanfeng %A CHEN Xue %A SHEN Yan %T Remediation Effects of Microbial Agents in Soil on Tobacco Plants Phytotoxicity Caused by Soil Quinclorac Residues %D 2018 %R 10.16409/j.cnki.2095-039x.2018.05.018 %J Chinese Journal of Biological Control %P 779-790 %V 34 %N 5 %X To provide scientific reference for microbial agents remediation on phytotoxicity in tobacco caused by quinclorac in tobacco production. Quinclorac was simulated of 0.2 mg/kg residual in soil, tobacco "Yunyan 87" was used in pot experiments to investigate the remediation effects of Fullbelief, Gefu microbial agent, Microbial inoculant Xianfeng 168 and Bacillus cereus LY05 on the phytotoxicity in tobacco caused by quinclorac. The remediation indexes were mainly focused on the plant growth, physiological and biochemical indexes, chemical components of tobacco leaves, and the degradation of quinclorac residues in tobacco leaves and soils. The results indicated that by using the four kinds of microbial agents in soil, the symptoms could be remediated. The Fullbelief (1:500 times liquid-filling root, 500 mL bacterial volume) had the best remediation effect. After transplanting for 30 and 60 d, the leaf length, leaf width, plant height and stem girth were promoted significantly (P<0.05, the same below), and the fresh dry weight on the ground and lower parts of tobacco were increased. The length of main root was the longest, significantly higher than that of the drug control by the rate of 41.65%. Compared with the drug control, the superoxide (SOD), catalase (CAT), glutathione (GSH) enzyme activities and soluble protein content in the damaged tobacco leaf were increased by 56.51%, 42.42%, 24.47% and 0.5%, respectively, while the malondialdehyde (MDA) content in tobacco leaves was significantly reduced. The chemical composition of tobacco leaf was improved, and the ratio of sugar to sugar, sugar to alkali and nitrogen to alkali were 3.39, 6.99 and 1.06, respectively, which basically recovered to the level of high-quality tobacco. At the same time, the quinclorac residue in tobacco leaves and in the soil were the lowest in the period of tobacco leaves, with the values of 0.0356 and 0.0135 mg/kg, which dropped by 63.31% and 71.56%, respectively, compared with the control. Bacillus cereus LY05 had a good remediation effect on the phytotoxicity in tobacco caused by quinclorac. Application of B. cereus LY05 accelerated the degradation of quinclorac, significantly remediated the width of the damaged tobacco leaves and effectively soothed the shrinkage of tobacco leaves. This study provides a new method and microbial resource for the remediation of the soil and the damaged tobacco plants polluted by quinclorac and also for the development of compound microbial agent in the future. %U http://www.zgswfz.com.cn/EN/10.16409/j.cnki.2095-039x.2018.05.018