In this study, the herbicide MCPA sodium salt monohydrate (sodium (4-chloro-2 methylphenoxy) acetate has been studied as are presentative compound used in the agricultural field. Accordingly, direct photolysis and pho...In this study, the herbicide MCPA sodium salt monohydrate (sodium (4-chloro-2 methylphenoxy) acetate has been studied as are presentative compound used in the agricultural field. Accordingly, direct photolysis and photocatalytic experiments under artificial irradiation simulating solar light in laboratorial conditions were performed. Photocatalytic experiments were performed using TiO2 dispersed powder and as an immobilized thin layer on the surface of blue glasses. The obtained results of photolysis showed a poor efficacy toward degradation of MCPA sodium monohydrate, with half-life (t1/2) 6931.5 min. While, the addition of TiO2 dispersed powder to the photocatalytic process enhances the process dramatically with (t1/2) equal to 36.5 min;furthermore, complete mineralization had been reached after approximately 4 hours, whereas the addition of TiO2 through immobilized system led to enhance the degradation rate with 2236 min. as t1/2. In spite of this, using TiO2 supported on glass substrates with more improvements could be a promising alternative to conventional TiO2 suspension, and provides a clean treatment method.展开更多
The digestion regularity of MCPA, ametryn and dim＇on which were the active ingredients of 55% MCPA · ametryn · diuron WP in sugarcane leaves and soil of sugarcane plantation collected from Changsha of Hunan...The digestion regularity of MCPA, ametryn and dim＇on which were the active ingredients of 55% MCPA · ametryn · diuron WP in sugarcane leaves and soil of sugarcane plantation collected from Changsha of Hunan Province and Haikou of Hainan Province in 2009 and 2010were studied in the paper, and the results showed that these three agents had rapid digestion. The final residue test showed that beth MCPA and ametryn had not been detected in the study; the average resi- dues of diuron in the soil collected from Hunan Province in 2009 and 2010 were 0.018 and 0.015 mg/kg, respectively which were slightly larger than the critical value of 0. 013mg,/kg; diuron had no been detected in other treatments.展开更多
[ Objective] The paper was compare the control effects of different doses of MCPA-Na on weeds in foxtail millet field. [ Method ] Different doses of MC- PA-Na were sprayed on foxtail millet field, while artificial wee...[ Objective] The paper was compare the control effects of different doses of MCPA-Na on weeds in foxtail millet field. [ Method ] Different doses of MC- PA-Na were sprayed on foxtail millet field, while artificial weeding and spraying water was designed as control. The strain control effect and fresh weight control effect were calculated. [Result]The strain control effect and fresh weight control effect of 2 250 g/hm^2 MCPA-Na at 25 and 40 d post spraying were the best, and the fresh weight control effects reached 84.19% and 87.23%, respectively. Compared to CK, the yield increase effect of 1 500 g/hm^2 was the best, and the yield increase rate was 54.31% ; followed by 1 125 g/hm^2. Generally, 1 500 g/hm^2 was the best dosage of MCPA-Na in foxtail millet production. [ Conclusion]The paper provided a theoretical basis for screening the best dose of herbicide in foxtail millet production.展开更多
[ Objective] The purpose was to supply experimental base for preparing new types of high efficient and safe mixture herbicide for sugarcane field. [ Method ] The associated function of MCPA-isooctyl and ametryn on Dig...[ Objective] The purpose was to supply experimental base for preparing new types of high efficient and safe mixture herbicide for sugarcane field. [ Method ] The associated function of MCPA-isooctyl and ametryn on Digitaria sanguinalis and Celosia argentea was evaluated by co-tox. icity coefficient method by potting experiment. [ Result] When active ingredient of MCPA-isooctyl and ametryn was mixed in the proportion of 9： 5, there was obvious synergistic effect on D. sanguinalis and C. argentea, while the co-toxicity coefficients reached 156.24 and 140.40. Proportion method and bisection method were used to confirm the optimum proportion of various ingredients in mixture of MCPA-isooctyl and ametryn, and the optimum proportion was as follows： 35.4% MCPA-isooctyl, 19.6% ametryn, 10.0% emulsifier and the rest were solvents. The stability test indicated that each index of this EC was consistent with standard for pesticide EC. Field efficacy test of 55% MCPA-isooctyl and ametryn EC showed that most weeds in sugarcane field could be effectively controlled with the dose range of 1 073 -2 310 g （a. i. ）/hm^2. [ Conclusion ] Mixture product of ametryn and MCPA-isooctyl with high content was successfully developed, which had the advantages including high efficiency, broad spectrum, good economy and convenient utilization, etc.展开更多
文摘In this study, the herbicide MCPA sodium salt monohydrate (sodium (4-chloro-2 methylphenoxy) acetate has been studied as are presentative compound used in the agricultural field. Accordingly, direct photolysis and photocatalytic experiments under artificial irradiation simulating solar light in laboratorial conditions were performed. Photocatalytic experiments were performed using TiO2 dispersed powder and as an immobilized thin layer on the surface of blue glasses. The obtained results of photolysis showed a poor efficacy toward degradation of MCPA sodium monohydrate, with half-life (t1/2) 6931.5 min. While, the addition of TiO2 dispersed powder to the photocatalytic process enhances the process dramatically with (t1/2) equal to 36.5 min;furthermore, complete mineralization had been reached after approximately 4 hours, whereas the addition of TiO2 through immobilized system led to enhance the degradation rate with 2236 min. as t1/2. In spite of this, using TiO2 supported on glass substrates with more improvements could be a promising alternative to conventional TiO2 suspension, and provides a clean treatment method.
基金Supported by Scientific and Technological Projects of Nanning Municipal Science and Technology Bureau(20132308)
文摘The digestion regularity of MCPA, ametryn and dim＇on which were the active ingredients of 55% MCPA · ametryn · diuron WP in sugarcane leaves and soil of sugarcane plantation collected from Changsha of Hunan Province and Haikou of Hainan Province in 2009 and 2010were studied in the paper, and the results showed that these three agents had rapid digestion. The final residue test showed that beth MCPA and ametryn had not been detected in the study; the average resi- dues of diuron in the soil collected from Hunan Province in 2009 and 2010 were 0.018 and 0.015 mg/kg, respectively which were slightly larger than the critical value of 0. 013mg,/kg; diuron had no been detected in other treatments.
基金Supported by Special Fund for Construction of China Agricultural Industry Research System(CARS-07-13.5)
文摘[ Objective] The paper was compare the control effects of different doses of MCPA-Na on weeds in foxtail millet field. [ Method ] Different doses of MC- PA-Na were sprayed on foxtail millet field, while artificial weeding and spraying water was designed as control. The strain control effect and fresh weight control effect were calculated. [Result]The strain control effect and fresh weight control effect of 2 250 g/hm^2 MCPA-Na at 25 and 40 d post spraying were the best, and the fresh weight control effects reached 84.19% and 87.23%, respectively. Compared to CK, the yield increase effect of 1 500 g/hm^2 was the best, and the yield increase rate was 54.31% ; followed by 1 125 g/hm^2. Generally, 1 500 g/hm^2 was the best dosage of MCPA-Na in foxtail millet production. [ Conclusion]The paper provided a theoretical basis for screening the best dose of herbicide in foxtail millet production.
基金Supported by Guangxi Youth Fund Project(Guikeqing0832062)~~
文摘[ Objective] The purpose was to supply experimental base for preparing new types of high efficient and safe mixture herbicide for sugarcane field. [ Method ] The associated function of MCPA-isooctyl and ametryn on Digitaria sanguinalis and Celosia argentea was evaluated by co-tox. icity coefficient method by potting experiment. [ Result] When active ingredient of MCPA-isooctyl and ametryn was mixed in the proportion of 9： 5, there was obvious synergistic effect on D. sanguinalis and C. argentea, while the co-toxicity coefficients reached 156.24 and 140.40. Proportion method and bisection method were used to confirm the optimum proportion of various ingredients in mixture of MCPA-isooctyl and ametryn, and the optimum proportion was as follows： 35.4% MCPA-isooctyl, 19.6% ametryn, 10.0% emulsifier and the rest were solvents. The stability test indicated that each index of this EC was consistent with standard for pesticide EC. Field efficacy test of 55% MCPA-isooctyl and ametryn EC showed that most weeds in sugarcane field could be effectively controlled with the dose range of 1 073 -2 310 g （a. i. ）/hm^2. [ Conclusion ] Mixture product of ametryn and MCPA-isooctyl with high content was successfully developed, which had the advantages including high efficiency, broad spectrum, good economy and convenient utilization, etc.
