| It was of great value to develop a new kind of effervescent tablet herbicides to control various weeds in rice field, which was characterized by low mammalian toxicity, low residual, being friendly to environment, being easy to apply and safety.The toxicity of quinclorac and bensulfuron with different mix proportion to various weeds occurred in rice field and its safety to rice was evaluated in laboratory. And the best mix proportion of quinclorac and bensulfuron was 11.1-9.7:1.Different kinds of effervesce componets, dispersant, binder, glidant and diluent were screened. Results of their best dosage was quinclorac 16.5%, bensulfuron 1.5%, disintergrant (N2C) 30%, dispersant C2%, BA8%, SB1%, pulvis talci 10%, and lactose 31%.The influence of solvents, absorbing wavelength and pH value of mobile phase on effervescent tablet quality was investigated. The mobile phase acetonitrile/ water (70:30, by vol), pH 3.2 was adjusted with phosphoric acid, UV detection was set up at 250 nm.Study on toxicology of this new product by white rat acute oral and percutaneous toxicity, lagophthalmos and rabbit skin pungency tests showed that this product was low toxicity and low pungency, which was safe to manipulator and consumer.Application technology of this product was also studied. It should be applied 5 days after rice seedling was transplanted and the water layer in fields should be maintained for 5 days at the dose of 750-1350 g/ha.
|
PDF Full Text Request