Studies On The Action And Its Mechanism Of Brassinnolide For Reducing The Phytotoxicity Of Ethametsulfuron On Maize

Ethametsulfuron is an excellent kind of herbicide in controlling the weeds in rape fields . Its biological activities is very high and its using quantity is low. It can control both singleleaf weeds and doubleleaves weeds in rape fields effectively . It is safe to human,domestic animal and environment.But it remains in soil long while maize is very sentitive to it.There often happen that phytotoxicity of ethametsulfuron on maize. Therefore,how to reduce the phytotoxicity of ethametsulfuron on maize is a worthy research. Using safeners is the first effective measure. For that, the influence of ethametsulfuron on the growth of different maize species were measured by cultivating it in water and soil. The action and its mechanism of brassinolide for reducing the phytotoxicity of ethametsulfuron on maize are studied on the base of former studies . The main results were listed as followed:1. The action of brassinolide for reducing the phytotoxicity of ethametsulfuron on maize was determined by cultivating it in soil in indoors. The results showed: brassinolide can remarkably reduce the phytotoxity of 16.0μg/kg ethametsulfuron on maize with the concentrations of 0.01~0.04mg/L BR.The 0.02mg/Lbrassinolide can reduce the phytotoxity of 2.0-32.0μg/kg ethametsulfuron on maize with different extent.2. The field experimentation showed that the output reduction ratio of maize was when corn seed was treated with ethametsulfuron . Accordingly the mechanism of BR for protecting maize from the phytotoxicity of ethametsulfuron could be interrelated with its stimulation on the activity of ALS. 11.8% and seed soking with 0.02 and 0.04 mg · L-1BR,if 15gai/hm2 of ethametsulfuron was used,the output reduction ratio of maize was 0.2% and 0.1% respectively.BR was a potential safener.3.Seed soaking with BR could increase the content of branch amino acid obviously...