大栗鳃金龟生物学特性与防治研究     

卜万贵  尹承陇 《甘肃林业科技》1996,21(2):28-33,61

大栗鳃金龟自１９８５年首次在临夏太子山林区发生后，以５年为一周期于１９９０年、１９９５年定期发生。该虫以幼虫和成虫在土壤内越冬，也以幼虫和成虫对林木幼苗造成巨大为害。幼虫期采用５０％辛硫磷乳剂６００倍液、８０％敌敌畏乳剂６００倍液，防治效果达９０％以上。成虫期采用黑光灯诱杀、人工捕捉，２５％氧乐菊酿乳剂８００倍液或“６６６”烟剂防治，均能收到很好的效果。  相似文献   

竹提取物抗菌杀虫性能的研究进展   总被引：2，自引：0，他引：2  

龚金炎  吴晓琴  张英 《竹子研究汇刊》2006,25(3):28-30,31

竹子不同部位含有特征性的生物活性成分,将其开发成天然食品防腐剂和杀虫剂已成为当今的研究热点,该文综述了竹叶提取物、竹醋液、竹皮提取物的抑菌、杀虫作用及其相关研究进展,以期为竹子提取物在食品添加剂和生物农药领域的应用提供信息。  相似文献   

Predictive modes of action of pesticides in uterine adenocarcinoma development in rats     

Midori Yoshida  Kaoru Inoue  Miwa Takahashi 《Journal of toxicologic pathology》2015,28(4):207-216

Endometrial adenocarcinoma in the uterine corpus is a malignant cancer that occurs in menopausal women and aged rodents. Because of the similarities in pathogenesis and morphology of endometrial adenocarcinoma in rodents and humans, prediction of the modes of action (MOA) in uterine carcinogenesis is important for extrapolation of rodent data to humans. Three MOAs have been accepted as major pathways for uterine carcinogenesis in rodents: 1) estrogenic activity, 2) increased serum 17beta-estradiiol (E2) to progesterone (P4) ratio and 3) modulation of estrogen metabolism to produce 4-hydroxyestradiol via P450 induction. Inhibition of estrogen excretion and increased aromatase in situ in the tumor are also a potential pathway. Here, chemicals showing uterine carcinogenicity were chosen from approximately 300 pesticides evaluated in Japan within the past decade, and their mechanisms were predicted using parameters from mechanistic and toxicity studies. Seven pesticides increased uterine tumor formation in rats, and the pathways of 4 pesticides could be predicted based on various mechanistic studies. The MOAs of cyenopyrafen and benthiavalicarb-isopropyl were predicted to be modulation of estrogen metabolism, while those of pyriminobac-methyl and spirodiclofen were predicted to be increased E2 to P4 ratio. The driven pathways of metazosulfuron and isopyrazam could not be predicted using several mechanistic studies. No mechanistic studies have been reported for sedaxane, which has a chemical structure and toxicological profile similar to isopyrazam. Our results indicated that appropriate mechanistic studies are useful for mechanism prediction in risk assessment. From this analysis, a flowchart showing a decision tree for predictive MOAs in uterine carcinogenesis was proposed.  相似文献   

引江济汉工程起始段面源污染现状及防治对策     

邓强  于兴修 《绿色科技》2015,(2):190-192

指出了防治面源污染是保护水源地的重要措施。对引江济汉工程起始段面源污染现状进行了调查分析,结果表明:引江济汉工程运行后,农田面积减少了40%,其中部分农田改为蔬菜等经济作物用地;化肥使用总量下降了41.7%,农药的使用总量也呈相同趋势下降,但农用地的平均化肥、农药使用量未发生显著变化,工程前后基本持平;区内水渠、沟渠阻塞严重,配套基础水利设施匮乏,灌溉条件差,地表径流与灌溉用水任意流失,面源污染的潜在威胁大,急需采取有针对性的治理措施。有针对性地提出了面源污染防治对策建议。  相似文献   

Accounting for uncertainty in pedotransfer functions in vulnerability assessments of pesticide leaching to groundwater   总被引：1，自引：0，他引：1  

Stenemo F  Jarvis N 《Pest management science》2007,63(9):867-875

A simulation tool for site-specific vulnerability assessments of pesticide leaching to groundwater was developed, based on the pesticide fate and transport model MACRO, parameterized using pedotransfer functions and reasonable worst-case parameter values. The effects of uncertainty in the pedotransfer functions on simulation results were examined for 48 combinations of soils, pesticides and application timings, by sampling pedotransfer function regression errors and propagating them through the simulation model in a Monte Carlo analysis. An uncertainty factor, f(u), was derived, defined as the ratio between the concentration simulated with no errors, c(sim), and the 80th percentile concentration for the scenario. The pedotransfer function errors caused a large variation in simulation results, with f(u) ranging from 1.14 to 1440, with a median of 2.8. A non-linear relationship was found between f(u) and c(sim), which can be used to account for parameter uncertainty by correcting the simulated concentration, c(sim), to an estimated 80th percentile value. For fine-textured soils, the predictions were most sensitive to errors in the pedotransfer functions for two parameters regulating macropore flow (the saturated matrix hydraulic conductivity, K(b), and the effective diffusion pathlength, d) and two water retention function parameters (van Genuchten's N and alpha parameters). For coarse-textured soils, the model was also sensitive to errors in the exponent in the degradation water response function and the dispersivity, in addition to K(b), but showed little sensitivity to d. To reduce uncertainty in model predictions, improved pedotransfer functions for K(b), d, N and alpha would therefore be most useful.  相似文献   

Herbicide risk assessment during the Wheat Self-sufficiency Project in Iran     

Deihimfard R  Zand E  Damghani AM  Soufizadeh S 《Pest management science》2007,63(10):1036-1045

BACKGROUND: The present study describes the quantitative changes in herbicide use during the specific observation periods in the Wheat Self-sufficiency Project in Iran from 1994 to 2004 and the associated changes in herbicide risk, area and yield in this context. A risk index, the environmental impact quotient (EIQ), was used to estimate the environmental impacts (EIs) of herbicides applied to wheat agroecosystems. RESULTS: The results suggest that, during this period, the overall risk posed by the herbicides applied to wheat agroecosystems increased substantially, as evidenced by a 71% increase in herbicide usage (weight of pesticide applied) and a 62.2% increase in EI rating, in spite of an 8.2% decrease in overall EIQ rating and an 89.2% decrease in mean application rate. Furthermore, a 0.57% increase in the area and a 23.6% and 22.7% increase in irrigated and rainfed yields, respectively, were observed. The results also indicate that the EIQ(FUR) of two herbicides, dichlorprop-P/mecoprop-P/MCPA and difenzoquat, is much higher than that of other herbicides, and they could be qualified as high-risk herbicides. CONCLUSION: As a whole, an increase in herbicide usage (weight of pesticide applied) was an important factor on herbicide environmental impact boost. However, this increase has not led to a similar increase in wheat yield, which could be attributed in part to the negative impact of high herbicide consumption in wheat fields and subsequent threat to the long-term sustainability of these agroecosystems.  相似文献   

Testing MACRO (version 5.1) for pesticide leaching in a Dutch clay soil   总被引：2，自引：0，他引：2  

Scorza Júnior RP  Jarvis NJ  Boesten JJ  van der Zee SE  Roulier S 《Pest management science》2007,63(10):1011-1025

Testing of pesticide leaching models against comprehensive field-scale measurements is necessary to increase confidence in their predictive ability when used as regulatory tools. Version 5.1 of the MACRO model was tested against measurements of water flow and the behaviour of bromide, bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one-2,2-dioxide] and imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] in a cracked clay soil. In keeping with EU (FOCUS) procedures, the model was first calibrated against the measured moisture profiles and bromide concentrations in soil and in drain water. Uncalibrated pesticide simulations based on laboratory measurements of sorption and degradation were then compared with field data on the leaching of bentazone and imidacloprid. Calibrated parameter values indicated that a high degree of physical non-equilibrium (i.e. strong macropore flow) was necessary to describe solute transport in this soil. Comparison of measured and simulated bentazone concentration profiles revealed that the bulk of the bentazone movement in this soil was underestimated by MACRO. Nevertheless, the model simulated the dynamics of the bentazone breakthrough in drain water rather well and, in particular, accurately simulated the timing and the concentration level of the early bentazone breakthrough in drain water. The imidacloprid concentration profiles and its persistence in soil were simulated well. Moreover, the timing of the early imidacloprid breakthrough in the drain water was simulated well, although the simulated concentrations were about 2-3 times larger than measured. Deep groundwater concentrations for all substances were underestimated by MACRO, although it simulated concentrations in the shallow groundwater reasonably well. It is concluded that, in the context of ecotoxicological risk assessments for surface water, MACRO can give reasonably good simulations of pesticide concentrations in water draining from cracking clay soils, but that prior calibration against hydrologic and tracer data is desirable to reduce uncertainty and improve accuracy.  相似文献   

昆虫几丁质合成关键酶功能及其RNAi技术在害虫防治中的研究进展     

许静静  李思琪  任梦圆  薛雨欣  李永强 《陕西农业科学》2022,(8):1-10

几丁质对昆虫的生长发育至关重要,且不存在于植物和哺乳动物中,因此其合成途径的关键酶是较为理想的杀虫剂靶标。近年来,多种害虫的几丁质合成关键酶基因被克隆和鉴定,通过RNAi技术应用于一些重要害虫的防治研究工作中。本文较为系统的总结了近些年害虫几丁质合成关键酶的基因克隆及功能研究进展,重点阐述了几丁质合成酶、海藻糖酶基因基于RNAi技术应用于害虫防治取得的研究进展,分析了RNAi技术通过转基因植物表达dsRNA（RNAi抗虫作物）以及作为核酸农药（dsRNA）直接进行作物喷施的两种应用途径,文章最后还探讨了RNAi在害虫防治中面临的主要瓶颈问题以及主要应对策略。上述较为系统的归纳和总结,目的是为今后基于几丁质合成关键酶的RNAi技术应用于害虫绿色防控研究提供有价值的理论指导。  相似文献   

我国烟草主要病虫害防治药剂登记现状与发展对策     

魏彬  林壁润  孙大元  郭俊杰  沈会芳  蒲小明  陈泽鹏  杨祁云 《广东农业科学》2021,48(3):105-114

烟草是我国重要的经济作物,病虫害防治是其种植过程中需要解决的主要问题。目前烟草病虫害主要有斜纹夜蛾、烟青虫、烟蚜、小地老虎、黑胫病、病毒病、赤星病、炭疽病和青枯病等。在病虫害防治方面,部分烟区仍存在使用高毒化学药剂、农药品种单一、偏向传统剂型等现象,造成病虫害抗药性提高以及烟叶农药残留超标;另外,由于化学药剂使用不当使烟草或其他轮作作物产生药害,严重影响土壤性质及农业生产,因此合理选用安全有效的药剂防治烟草病虫害亟待解决。总结和分析了截至2020年12月7日在我国烟草主要病虫害防治药剂登记的基本情况及存在问题,经与同类病虫害使用药剂的登记情况进行比较分析,以期对烟草主要病虫害防控用农药登记现状有一个基本了解,并提出今后烟草主要病虫害防治药剂登记对策,为提高烟草病虫害绿色防控的农药合理使用技术水平提供保障。  相似文献   

原子荧光光谱法测定农药中砷和汞的方法研究     

杜英秋 《黑龙江农业科学》2014,(9):89-93

农药中的砷、汞是使农产品产生毒性的重要原因,为探究农药中砷和汞同时检测的方法,通过原子荧光光谱对农药中砷和汞进行测定,讨论了不同前处理方法对测定结果的影响,最终确定了王水消解样品-原子荧光光谱法同时测定砷和汞的方法,该方法对砷和汞的回收率分别为90.1%~104.0%和89.5%~96.2%,检出限为0.14和0.003 1ng·mL-1,RSD为4.9%和5.2%,当砷的质量浓度处于0~100.0ng·mL-1,汞的质量浓度处于0~2.0ng·mL-1时,标准曲线均能呈良好的线性关系,相关系数分别为1.000和0.999 8,结果满意。  相似文献