Preparation And Application Of 10% Mesotrione Oil Suspension Concentrate

Maize is an important food and feed crop in our country, chemical weeding urgently need broad spectrum, high effect and environment-friendly foliarly applied herbicide in corn field. In the past few years, mesotrione was an important foliarly applied herbicide in corn field.Based on processing preparation of mesotrione and filtering oil dispersed mediums enhanced mesotrione activity. the research is to study and develop new foliarly applied herbicide-10% mesotrione oil suspension concentrate which has the high efficiency, low residue and amity to environment. concern with some systemic research on preparation directions as well as technics conditions, The research testifies the activity of mesotrione and the safety to crops by potted methods in Greenhouse and field trials. Summarizing the application technology of mesotrione. The research showed the results as follows:1 The choice of medium oil: by greenhouse whole-plant bioassays experiment, it is screened out that: methyl oleate as dispersing medium of oil-suspended injection had notable effect of synergism to mesotrione form corn oil soybean oil rapeseed oil and methyl oleate.2. Surfactant, thickener and other components of oil suspension concentration were screened and confirmed by the optimized combination tests. SND-1 and SND-2 were selected as the surfactant monomer, with the ratio of SND-1 to SND-2 being 2:1, and M and organosilicon were chosen as the thicker and defoaming agent, respectively. Based on these tests, the optimized combination of 10% mesotrione OF was as the following: 10% mesotrione, 14% surfactant, 2% thickener M, 0.1% defoaming agent organosilicon, and with methyloleate adjuvant to make up 100%.3. Mesotrione was separated and determined from the sample adopting High Performance Liquid Chromatography. The stationary phase was Diamonsil C18 and the mobile phase was methanol and water (0.03mol/L potassium dihydrogen phosphate solution,using phosphoric acid to adjust pH=3.0) =500+500(v+v). The detection wavelength was 254 nm. This method was accurate and exact and it can be repeated well. Its excellence was fast,accurate and convenient.4. Determination and study on the pH,suspensibility,pourability,sieve,lasting formability,low temperature stability,heat temperature stability such technical indexes, the result indicates that the 10% mesotrione quality is reliable,and accord with relevant regulations of the similar products. According to the production status in China and physicochemical properties of mesotrione and referring to quality index of some OF, making quality control index of 10% mesotrione.5. The indoor activity test and the field trials showed that the developed 10% mesotrione oil suspension concentrate had a high stem and leaf treatment. It was applied to summer-grown maize field at maizes'3-5 leaf stage and at weeds 2～5 leaf stage had high efficacies in controlling familiar annual gramineous and broadleaf weeds ,and it was safe to maize. The recommended field doses were 150～175g a.i./hm2.