Effect of Different Post-emergence Herbicides to Maize

GENG Ya-ling;LIU Bo-yan;WANG Hua;HUN Zhi-ying;Institute of Plant Protection,Hebei Academy of Agriculture and Forestry Sciences,IPM Centre of Hebei Province,Key Laboratory of Integrated Pest Management on Crops in Northern Region of North China,Ministry of Agriculture;

Maize security;;Atrazine;;Nicosulfuron;;Mesotrione;;2,4-D butylate

[Objective] The aim was to test the safety of maize to 4 post-emergence herbicides,and provide reference for guiding the rational use of herbicides in production. [Method] In the pot experiment,the phytotoxicity symptoms of different dosages atrazine,nicosulfuron,mesotrione,2,4-D butylate on maize was studied,as well as the plant height and fresh weight. [Result] Atrazine was very safe to maize at the tested dosages,which were 0. 5-5. 0 fold to the recommended dosage. Mesotrione could cause phytotoxicity symptoms to maize at higher doses,which were 3. 0-5. 0 fold to the recommended dosage,but the phytotoxicity could recover by itself on 30 th day after the application,and didn't markedly affect the height or the fresh weight of maize. Nicosulfuron could reduce the height of maize,but not the fresh weight at higher doses. 2,4-D butylate could reduce both the height and the fresh weight of maize. [Conclusion] The order of the safety of 4 tested herbicides from high to low is atrazine,mesotrione,nicosulfuron and finally 2,4-D butylate.