Study On The Preparation Of 40% Benazolin-ethyl. Haloxyfop-R-methyl Water Dispersible Granules

Chongqing is an important production base of rape plants in the middle and upper reaches of Yangtze River. It offers a large variety of rape, including Napus as the main type, as well as many leaf mustards rape and the cabbage rape. Now, the variety of herbicide used in rape field is comparatively limited, which is mainly used before transplant, for example, acetochlor and glyphosate. Acetochlor and glyphosate hardly keep effective to weed after rape were transplanted, and can not control weed for a long time. Therefore, it is urgent to develop new herbicide products, which were used at the developmental stage of rape in Chongqing area.Water dispersible granule was a new pesticide formulation growing rapidly in America and Europe in 1980s for it keeps all merits of granule and high dispersibility of suspension agent and avoids the dust pollution of wettable powder and instability of physicochemical properties.The paper adopts the composition of benazolin-ethyl and haloxyfop-R-methyl to extirpate weed in brassica napus fields from the aspects of the determination of toxicity, the determination of safety and the determination of sutiability. Processed through the formulations, benazolin-ethyl and haloxyfop-R-methyl will be processed into 40% Benazolin-ethyl. Haloxyfop-R-methyl WDG, and then established a 40% Benazolin-ethyl·Haloxyfop-R-methyl WDG test detection methods, and through the product quality inspection, the final test carried out 40% Benazolin-ethyl Haloxyfop-R-methyl WDG of the field trials. The main research methods and results are summarized as follows:1 Determination of ToxicityFAO recommended using leaf spray method, measured Quizalofop, Haloxyfop-R-methyl, Clethodim on Barnyardgrass activity and Benazolin-ethyl, Ethametsulfuron and Fluoroglycofen ether of the Rape of security. The results showed that the highest activity against weeds is the Haloxyfop-R-methyl (EC₅₀= 8.6433 g/L), the security of rape is the highest Benazolin-ethyl (Brassica napus selective index of 2.4), so the option to experiment with Benazolin-ethyl and Haloxyfop-R-methyl complex to weed control in rape. The experiments measured the Benazolin-ethyl and Haloxyfop-R-methyl, the best ratio of 3～4:1, due to broad-leaved weeds in oilseed rape fields mainly weed, and Control in difficult, so experiment to determine the best ratio of Benazolin-ethyl and Haloxyfop-R-methyl for the 4:1.2 40% Benazolin-ethyl·Haloxyfop-R-methyl WDG Formula to DetermineThrough Wetting agent, Vector, Dispersant, Disintegrant and so on screening, and formulation optimization through the orthogonal design experiment to determine 40% Benazolin-ethyl Haloxyfop-R-methyl WDG, the final formula for Benazolin-ethyl32%, Haloxyfop-R-methyl 8%, Silica 8%, K12 2%, Lignosulfonate 10%, Ammonium 5%, Kaolin supplement 100%.3 The Quality Testing and Analysis Method Found of 40%Benazolin-ethyl·Haloxyfop-R-methyl WDGAccording to the method commended by FAO and GB, the samples are determined from the following aspects:suspension, percentage, wettability, dispersibility, disintegrative, stability of heat retaining, PH and fineness. The performance index of 40%benazolin-ethyl·haloxyfop-R-methyl WDG lies as follows:gray granules of prismatic structure with 1-2mm in diameter is formed; the wetting time is 8.2s; the suspension rate is 87.88%; disintegration time is 46.8s; PH is 6.667; moisture content is 0.47%; the decomposition rate after heat storage of benazolin-ethyl is 0.84%, the decomposition rate after heat storage of haloxyfop-R-methyl WDG is 1.74%。All these performance figures conform to the national standard.4 40% Benazolin-ethyl·Haloxyfop-R-methyl WDG Rape Weed Control in Field TrialsReferring to the rules of field trials, the research on the effect of 40% Benazolin-ethyl Haloxyfop-R-methyl WDG on rape is done in Tongnan of Chongqing province. Both of the experimental chemical and the control group chemical are effective. The effectiveness reaches highest after 30days. For the effect, there is no significant difference between the experimental chemical and the control group chemical. More, no chemical damage phenomenon is caused. Following the principles of economics, high rate and environment protection,250 g·ai/ha of 40% Benazolin-ethyl. Haloxyfop-R-methyl WDG is commended.