Herbicide Phytotoxicity And Its Restoration Measures In The Tobacco-rice Rotation System

Decreasing the losses of tobacco production caused by the herbicide phytotoxicity, and increasing the economic benefits of the farmer in the tobacco production, which was vital significance to the health development of modern tobacco agriculture. Tobacco-rice rotation system as the object, and four experiments of different herbicide was design, from herbicide phytotoxicity and its restoration measures of tobacco caused by previous crop and paddy period in the tobacco, the paper was study the effect of herbicide phytotoxicity on tobacco growth & development, and put forward restoration measures for repairing herbicide phytotoxicity. Main results were shown as follows:(1) In the tobacco-rice rotation system, the application of quinclorac in rice season affects tobacco growth and development. In the rice season, more than 1500 g/hm2 of total usage amount in the quinclorac (50% active ingredients) occurs moderately and severe herbicide phytotoxicity, meanwhile, more than 750 g/hm2 of total usage amount in the quinclorac (50% active ingredients), the content of quinclorac tobacco leaves was 0.00648?0.103 mg/kg, and the content of quinclorac in the soil was 0.169?0.772 mg/kg, seriously affecting the quality of tobacco leaf and subsequent processing production.(2) Glyphosate was suitable of pre-emergence herbicide, its usage amount was recommended within 2 times of the usage dosages; After pre-emergence herbicide, appropriate tobacco herbicides was Yanruyi herbicide, which was applied weed control in the paddy field of tobacco, was a relatively safe, it was a popular long after bud herbicide; Baocheng herbicides was only suitable with the furrow in the tobacco field, and could not produced herbicide phytotoxicity of tobacco plant; four herbicides, such as Fomesafen, Yanzhichu, Xinbaichu, YeLao, were not suitable for weed control of tobacco period in the paddy field.(3) Different restoration repairs have been relief herbicide phytotoxicity of quinclorac residues, tobacco agronomic traits in biochar (T1) and plant power+gibberellin (T4) was best in the resettling period and vigorous growing stage, its incidence was also same with that was the best. Tobacco leaf yield and output value in the T1, T4 treatment was higher, the T1, T4 treatment could effectively repair quinclorac residual of the effects on tobacco growth & development, and increase the proportion of upper tobacco leaves, increase tobacco production, compared with CK, improve the output per unit area, repair effect was relatively better.