Effect of pesticides on phosphate solubilization by Bacillus sphaericus and Pseudomonas cepacia

Intensive screening of phosphate solubilizing bacteria with genetic potential for increased tolerance to high salt, high pH and high temperature could enhance production of food and forage in semi-arid regions. Emphasizing particularly on this hypothesis 165 phosphate solubilizing bacteria was isolated. Among these, two cultures Bacillus sphaericus and Pseudomonas cepacia were selected on the basis of salt tolerance property and PS activity with different forms of phosphates. In the present investigation both these culture were assessed for the effect of six different pesticides, to confirm its successful realistic application as microbial inoculants in actual farm conditions. Both cultures showed better phosphate solubilizing activity with phosphate containing pesticides. Among these two isolates P. cepacia was a better performer in terms of phosphate solubilizing activity with different pesticides. It may be due to its well documented extra ordinary, versatile metabolic activity. The present study may prove them to be potential candidates to be used as microbial inoculants.     

葡萄酒中农药残留的色谱分析法研究进展

概述了目前应用于研究检测葡萄酒中农药残留的色谱分析方法的研究进展，主要分析方法包括：气相色谱（GC）分析法、液相色谱（HPLC）分析法、气相色谱-质谱联用（GC/MS）分析法、液相色谱-质谱联用（HPLC/MS）分析法。并对目前葡萄酒农药残留的现状进行了分析。     

影响农药在土壤与沉积物上吸附作用的研究

农药是环境中重要的有机污染物之一，吸附作用是农药在土壤/沉积物环境中的重要迁移转化行为之一。从农药的性质结构、土壤/沉积物的组成、温度、pH值和共存有机化合物等几方面，阐述了上述因素对农药在土壤/沉积物上吸附作用及其机理的影响，并提出了该领域存在的问题及今后发展的方向。     

中国苹果生产农药使用调查报告

选取96个主产区苹果园(其中,渤海湾地区61个,西北黄土高原地区35个)进行农药使用情况调查,明确了中国苹果生产中所用农药的品种、普遍使用的农药及农药使用的合理性。建议加强农药使用的指导监督和标准制修订,克服抗药性。     

Detection of pesticides used in rice cultivation in streams on the island of Leyte in the Philippines

Targeted sampling of water was performed in streams, the river mouth, and the municipal drinking-water tap in the vicinity of San Francisco, South Leyte, Philippines. Samples were processed on site and transported back to Sweden for analysis by gas chromatography mass spectrometry to identify and quantify the pesticides commonly used in the area. Collaborations were initiated with employees at the local Department of Agriculture and Municipal Disaster Coordinating Council to learn more about the rice cultivation in this area and times for spraying. Detectable levels of pesticides λ-cyhalothrin, cypermethrin and deltamethrin (0.0005-1.4 μg/L) were found in representative water samples. In 47% of samples the detected levels exceeded the recommended limit values for pesticides in surface water according to Swedish guidelines (Swedish Chemicals Agency, 2008). The analysis of samples taken at the river mouth revealed measurable levels of λ-cyhalothrin and cypermethrin, which means that residues of pesticides applied to rice paddy fields were shown to end up at the river mouth. The success of the sampling and analysis methods was confirmed by the data which was in accordance with the expected effect of dilution from day to day. Variable levels of insecticides in the river and all the way down to the sea may have adverse health effects on people using the water and on the aquatic environment, including sensitive coral reefs. This situation is applicable not only to the Philippines, but also to the whole of Southeast Asia, with approximately 70% of their human population living in coastal areas. As Southeast Asia encompasses approximately 34% of the world's coral reefs and between a quarter and a third of the world's mangroves, as well as the global biodiversity triangle formed by the Malay Peninsula, the Philippines, and New Guinea, the need to reduce the impacts of marine pollution in this region is of great importance.     

长绿飞虱对几种常用杀虫剂的敏感性测定

为了明确不同常用杀虫剂对长绿飞虱的防治效果,采用浸叶法测定了8种杀虫剂对长绿飞虱的室内生物活性。研究结果表明,噻嗪酮、啶虫脒对斜纹夜蛾的活性最高,LC50为0.189 3 mg/L与1.087 8 mg/L;杀虫单、吡蚜酮、三唑磷等农药对长绿飞虱的活性较低。     

药剂防治水稻稻瘟病及施药技术的初步研究

研究稻瘟病的药剂防治,结果表明:20%氰菌胺SC 750～1 000 g/hm2对水750 kg/hm2防治稻瘟病效果显著;其次为40%富士1号EC 1 250 g/hm2对水750 kg/hm2.在施药技术上应注意多种药剂交替使用,在叶瘟发生初期及破口和齐穗期雨前各施药1次,可以有效控制稻瘟病的发生危害.分析了稻瘟病发生流行的影响因素,评价了常用的稻瘟病防治药剂.     

Pesticide use in rice and rice–fish farms in the Mekong Delta, Vietnam

Pest management practices among rice and rice–fish farmers and their perception of problems related to pests and pesticides were surveyed in the Mekong Delta. A total number of 64 different pesticides were identified during the survey. Approximately 50% were insecticides, 25% were fungicides and 25% were herbicides. The main insecticides used were pyrethroids (42%) carbamates (23%) and cartap (19%). Non-IPM farmers used twice as many pesticides as IPM farmers. Their application frequency and the amount of active ingredient used were 2–3 times higher per crop, as compared to IPM farmers. During the last three years IPM farmers estimated that they had decreased the amount of pesticides used by approximately 65%, while non-IPM farmers said that they had increased the amount of pesticide used by 40%. Also, farmers growing fish in their rice fields used less pesticide than farmers growing only rice, as pesticides adversely affect cultures of fish. Taking a long-term perspective integrated rice–fish farming with IPM practices provides a sustainable alternative to intensive rice mono-cropping, both from an economic as well as an ecological point of view.     

Droplet size spectra and drift effect of two phenmedipham formulations and four adjuvants mixtures

The effect of 4 adjuvants on two formulations of phenmedipham (EC and SC) applied with three types of hydraulic nozzles (hollow cone, flat fan and air induction) was evaluated using a wind tunnel to determine spray drift potential (DP). The volume median diameter (VMD) and the percentage by volume of droplets less than 100 μm diameter was determined using a Malvern particle size analyser. In a wind tunnel DP was measured between 2 and 6 m downwind of the nozzle on glass fibre collectors using a fluorescent tracer. The EC formulation produced a smaller VMD and larger DP than the SC formulation irrespective of any effect due to adjuvants. DP increased as the proportion of small droplets increased.     

Adsorption of atrazine and metolachlor in three soils from Blue Creek wetlands, Waterville, Ohio

Atrazine and metolachlor are extensively used pesticides in agricultural activities in northwest Ohio. Adsorption coefficients are often used to model pesticide fate and transport. Many physical-chemical parameters, such as organic matter, clay content, pH, and ionic strength, affect pesticide adsorption. Adsorption kinetics and adsorption isotherms were studied by batch experiment. Effects of humic acid, solution pH, and ionic strength on atrazine and metolachlor adsorption were also approached. After 24 h, both atrazine and metolachlor reached adsorption equilibrium in three local soils. Adsorption isotherms were described by Freundlich equations. The Freundlich coefficient (Kf) ranged from 0.14 to 4.47 (L kg^–1) for atrazine, and 0.04 to 5.30 (L kg^–1) for metolachlor. Adsorption capacity decreased in the order Sloan loam > Del Rey loam > Ottokee fine sand. Koc values varied considerably for both pesticides: metolachlor > in Sloan loam, atrazine metolachlor in Del Rey loam, and atrazine > metolachlor in Ottokee fine sand. In addition to organic matter content, clay played a key role in adsorption in the Del Rey loam and Ottokee fine sand. Higher adsorption was observed at pH 5 for both pesticides. As pH decreased to 3 and increased to 11, adsorption decreased. Adsorption increased as ionic strength increased.