Residue Analysis of 55% MCPA·ametryn·diuron WP

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.

Evaluation of the Genotoxicity of Polymeric Microparticles Containing Ametryn Herbicide

Agrochemicals have been used throughout the ages to eradicate weeds and pests. Use of agrochemicals is now commonplace, serving as an aid in farming procedures and contributing to greater agricultural production. However, the indiscriminate use of agrochemicals is a cause for concern because they can exert toxic effects on the environment and hence on living beings. This work involved a genotoxic analysis of controlled release formulations of the herbicide ametryn encapsulated in microspheres of poly（hydroxybutyrate） and poly（hydroxybutyrate-co^valerate）. Genotoxicity was analyzed using cytogenetic, micronucleus, comet and Allium cepa assays, as well as molecular analysis. The results showed that the rate of chromosome breakdown caused by unencapsulated ametryn was much higher than that caused by ametryn encapsulated in the polymer microspheres （p 〈 0.05）. This indicates that controlled release delivery systems employing the polymer formulations should be significantly safer for the environment and for living beings.

Preparation of 55% MCPA-isooctyl and Ametryn EC and Its Field Efficacy

[ 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.

Screening of Commercial Herbicides for Controlling Algae Growth in Aquarium

This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It is found that ametryn was the most effective herbicide that inhibited algal growth. Ametryn concentration that caused 50% inhibition on algae growth after exposure for 21 days was 0.335 ppm. Survival rate of oruamental fish, Harlequin rasbora （Trigonostigma heteromorpha） and growth rate of aquatic plant （Elodea canadensis） exposed to 10 ppm ametryn were compared with those exposed to algaecide. The result showed that there was no significant difference in survival rate of Harlequin rasbora when exposed to ametryn, algaecide and dechlorinized tap water （control）. However, growth rate of E. canadensis was lower after exposure of ametryn compared to those exposed to algaecide and tap water. These results suggest that ametryn has potential to be used as an algal inhibitor in aquarium.