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1.
The paper discusses the use of natural products and biological control agents in crop protection from an industrial viewpoint. The criteria which must be satisfied are noted. Examples are given from the genetic engineering of baculoviruses and proteins. The final section considers the utility of natural products as a source of leads for conventional agrochemicals, and the screens needed. © 1998 SCI.  相似文献   

2.
The work undertaken to isolate the novel, herbicidally active compound, carbocyclic coformycin, to obtain sufficient quantities of the compound for full biological evaluation, and to identify its biochemical mode of action is summarised. Although the compound was extremely active against some weed species, limitations in its spectrum of activity precluded further development. Carbocyclic coformycin exerts its biological action through a novel mode of action by the inhibition of the enzyme adenosine 5′-phosphate deaminase (EC 3.5.4.6) following phosphorylation in planta. From this work, the potential benefits of natural product research in the discovery of new agrochemicals are highlighted along with some of the possible pitfalls. © 1998 SCI.  相似文献   

3.
The relentless need for the discovery and development of new agrochemicals continues as a result of driving forces such as loss of existing products through the development of resistance, the necessity for products with more favorable environmental and toxicological profiles, shifting pest spectra, and the changing agricultural needs and practices of the farming community. These new challenges underscore the demand for novel, high‐quality starting points to accelerate the discovery of new agrochemicals that address market challenges. This article discusses the efforts to identify the optimum ranges of physicochemical properties of agrochemicals through analysis of modern commercial products. Specifically, we reviewed literature studies examining physicochemical property effects and analyzed the properties typical of successful fungicides, herbicides, and insecticides (chewing and sap‐feeding pests). From the analysis, a new set of physicochemical property guidelines for each discipline, as well as building block class, are proposed. These new guidelines should significantly aid in the discovery of next‐generation agrochemicals. © 2018 Society of Chemical Industry  相似文献   

4.
Against a background of the growing importance of single enantiomer agrochemicals, practical technologies for their production are reviewed. Methods range from extraction of natural products through to asymmetric synthesis and encompass physical, chemical and biological techniques.  相似文献   

5.
Plant breeding and selection, husbandry techniques and crop protection technology, including agrochemicals, have all made substantial contributions to the present-day level of crop productivity. However, yield losses due to disease, pests and weeds must continue to be minimized in order to meet the food supply demands from an ever growing population. Appropriate synthetic chemicals are becoming increasingly difficult to discover and develop due to stricter requirements on efficacy, selectivity, toxicology and general environmental impact. Consequently, there is a growing interest in understanding and utilising natural mechanisms as the basis for crop protection products. Plants themselves are a rich source of biologically active substances which could potentially be harnessed to modify crop growth or to protect crops against disease and pests. This review describes briefly the current status of understanding relative to plant–plant (herbicide and plant growth substances), plant–fungal (fungicide) and plant–insect (insecticide) interactions. Future prospects are considered in relation to directed synthesis, cell culture, microbial pesticides and plant genetic engineering. The opinion expressed is optimistic and suggests that science today can be utilised to secure the food supply of tomorrow. However, utilising either natural products or molecular biology may require an improved understanding of crop physiology and new developments in agronomy. Therefore, the time-frame for major impact of the ‘new’ technologies on crop productivity may be longer than is commonly predicted.  相似文献   

6.
Natural products containing a N‐heterocycle motif are widespread in nature and medicinal plants, in particular, have proved to be a source of almost unlimited N‐derived structures with high molecular diversity. Because of their intrinsic potential for use in both biomedical and agricultural applications, there is a general need for new compounds and for the synthesis of ‘natural‐inspired’ analogues. Importantly, transition of a natural product from discovery to a ‘market lead’ is associated with an increasingly challenging demand for more of the compound, which cannot be met by isolation from natural plant sources, often due to low extraction yields and uneven availability of the plant source itself. Synthesis remains the most reliable approach to provide valuable products for the market. In this review, a comprehensive overview of our contribution to synthetic access to N‐derived natural products is given. Major strengths of the proposed methodologies are discussed critically. © 2019 Society of Chemical Industry  相似文献   

7.
病虫草害防控是国家总体安全建设的重要组成部分。微生物天然产物农药是病虫草害绿色防控体系的重要成员, 在保障国家粮食安全、生态安全和农产品质量安全, 筑牢国家生物安全屏障中具有重要作用。链霉菌以能够产生丰富的次级代谢产物而著称, 是天然产物农药的资源宝库, 也是重要的天然产物药物的工业生产菌。然而, 随着病虫草害抗药性增强, 新发、突发病虫草害增多等问题不断涌现, 以及天然产物研究面临新骨架、高活性化合物发现难度增大, 工业菌株产量提升困难等瓶颈, 链霉菌天然产物农药创制与应用正面临巨大挑战。合成生物学作为一门交叉学科, 突破了生物学研究的传统模式, 为天然产物药物研发提供了新的思路与策略。本文综述了近年来合成生物学在链霉菌研究领域的技术革新, 以及合成生物学在推动链霉菌天然产物资源发现、天然产物高效生物制造等方面的研究进展, 并对合成生物学助力链霉菌天然产物农药的创制与产业化进行了展望。  相似文献   

8.
近红外光谱法快速测定农药中溴氰菊酯含量   总被引:3,自引:0,他引:3  
用近红外(NIR)光谱技术结合偏最小二乘法(PLS)进行了敌杀死乳油中有效成分溴氰菊酯含量的快速检测。通过比较敌杀死乳油与常用溶剂的近红外光谱,确定了乳油中使用的溶剂为二甲苯。在敌杀死乳油中加入二甲苯或溴氰菊酯原药来配制不同浓度的校正集,采用PLS建立了有效成分溴氰菊酯的分析模型,模型的决定系数R2、校正标准差(SEC)、交互验证参差均方根(RMSECV)值分别为0.999 9,0.013和0.022。结果表明:近红外光谱技术可以准确测定商品农药制剂中有效成分含量,方法简便、快速,适用于溴氰菊酯制剂的现场、在线分析。  相似文献   

9.
Higher plants offer an excellent source of biologically active natural products. Over the centuries numerous plants have been exploited as sources of insecticides, but nowadays traditional botanical insecticides play only a minor role in world agriculture. Nevertheless, plant natural products still have enormous potential to inspire and influence modern agrochemical research. Few plant natural products will ever reach the market as products per se, but others will provide lead structures for programmes of synthetic chemistry and hopefully follow the success story of the synthetic pyrethroids. Structurally complex compounds, which are not amenable to synthetic chemistry programmes, may also have a role to play by validating new modes of action for pesticides. Examples are presented of compounds exhibiting insecticidal, fungicidal and herbicidal effects. Consideration is also given to the development of screening programmes to detect new compounds with interesting biological properties. Careful experimental design and thorough recording of procedures and data are crucial to success. Badly designed programmes afford only weakly active compounds or show effects which cannot be reproduced at a later date. Natural product chemistry, whether based on higher plants, micro-organisms or other sources, is a very difficult science, but there is little doubt that dedicated research will eventually be rewarded with exciting new lead structures for industrial application.  相似文献   

10.
Over the last 20 years the share of the crop protection market attributable to the leading markets (North America, EU‐15 and Japan) that are the major focus of new active ingredient research and development (R&D) has declined. Greater growth has been recorded in developing markets, questioning the focus of current R&D strategy. R&D budgets within the major companies have seen a shift toward genetically modified (GM) trait development away from agrochemicals, such that the rate of new active ingredients entering development and subsequently being introduced has declined. As a result, the industry has become more reliant on older, off‐patent chemistry, although the availability of older products has been affected by re‐registration requirements, particularly in the EU. Current criteria often preclude the registration of broad‐spectrum agrochemicals, resulting in many new active ingredients being single site active, which is perceived to increase the potential for resistance development, particularly for herbicides, although this is not always the case. © 2019 The Author. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

11.
海藻糖是一种非还原性二糖,在昆虫、真菌等有害生物体内参与能量代谢、逆境恢复、几丁质合成等过程。海藻糖酶 (EC 3.2.1.28) 由于其对海藻糖代谢及其含量调控具有重要作用,且在农业有害生物和哺乳动物体内存在功能差异,已成为开发新型农用化学品的安全型候选靶标。本文对海藻糖酶的晶体结构、海藻糖酶与底物/抑制剂的互作机制研究进展进行了综述;同时对具有农用活性的海藻糖酶抑制剂,如井冈霉素、天然产物salbostatin和trehazolin及其合成类似物、脱氧野尻霉素及其合成类似物、天然生物碱及其合成类似物以及胡椒碱及其类似物的研究进展进行了概述,并重点论述了以胡椒碱为骨架的化合物在农业有害生物防治上的应用。本综述可为靶向海藻糖酶结构进行新型胡椒碱类结构的农用化学品设计与发现提供参考。  相似文献   

12.
The synthesis of propesticides is an important concept in design of modern agrochemicals with optimal efficacy, environmental safety, user friendliness and economic variability. Based on increasing knowledge of the biochemistry and genetics of major pest insects, weeds and agricultural pathogens, the search for selectivity has become an ever more important part of pesticide development and can be achieved by appropriate structural modifications of the active ingredient. Propesticides affect the absorption, distribution, metabolism and excretion parameters, which can lead to biological superiority of these modified active ingredients over their non‐derivatised analogues. Various selected commercial propesticides testify to the successful utilisation of this concept in the design of agrochemicals. This review describes comprehensively the successful utilisation of propesticides and their role in syntheses of modern agrochemicals, exemplified by selected commercial products coming from different agrochemical areas. © 2015 Society of Chemical Industry  相似文献   

13.
α -氨基酸是具有重要生理功能和结构功能的生物小分子,同时也是重要的化工原料。综述了 α- 氨基酸及其衍生物在农药合成中的研究及应用情况,特别是在手性农药的制备中, α -氨基酸不仅可作为天然手性合成子直接参与合成反应,而且在手性拆分、不对称合成等方面也起着重要的作用。  相似文献   

14.
防控大豆病害的农药登记现状及发展对策   总被引:1,自引:0,他引:1  
在分析大豆生产和病害危害的基础上,对我国大豆生产中防控病害的农药登记现状进行了统计分析。目前我国大豆上登记的杀菌剂有效成分12个,产品64个,分别占61个总有效成分数量的19.67%,306个总产品数量的20.92%;其中福美双、多菌灵和克百威不同配比的混配产品在2002年前占登记杀菌剂产品的82%以上;登记的靶标病害包括大豆根腐病、紫斑病、孢囊线虫病、锈病和病毒病等5种,占国内已经报道的33种病害总数的15.15%。目前丁硫克百威、毒死蜱和阿维菌素等替代高毒的克百威与福美双、多菌灵混配的种衣剂产品登记发展较快;甲氧基丙烯酸酯类杀菌剂嘧菌酯和三唑类杀菌剂戊唑醇、苯醚甲环唑和丙环唑先后取得登记,对防控大豆锈病等具有较好效果。建议加速具有针对性、超前性的杀菌剂新有效成分及新产品的研究开发,推进"小范围使用登记",促进我国大豆病害防控的可持续发展。  相似文献   

15.
设计调查问卷,对河北、湖南和陕西3省共计184户农户实施抽样调查,系统分析我国蔬菜安全生产中农药使用现状。结果表明:1.我国农药使用群体以中老年男性为主,其中54.35%教育程度为初中学历,选购农药时主要根据经验判断、经销商推荐的分别占59.24%和48.91%。2.配药过程粗放,简单使用瓶盖量取、估测后直接倒进喷雾器的分别为28.26%、25.54%。3.施药时缺乏安全防护意识,选择戴口罩比例仅为31.52%。4.只有20%的农户遵照农药标签上的安全间隔期收获作物,66.3%的农户从未参加过农药方面的培训。分析认为,我国农药使用群体受教育水平、科学素养、安全和环境保护意识急需提高;加强农药市场监管和技术培训宣传,对推动农户科学使用农药,加速蔬菜安全生产进程具有重要意义。  相似文献   

16.
新农药创制是一项艰难复杂的系统性工程,而新农药分子的设计是该工程的源头,也是最重要的一环。文章对传统的农药分子设计方法进行了简单的归纳总结,并在课题组多年新农药创制实践的基础上提出了一种新的设计方法——分子插件法,并以吡啶二芳酮和芳氧吡啶乙酮为例,介绍了分子插件的设计及其在新农药创制中的应用。该方法的优点在于可将功能基团模块化,便于快速衍生和筛选,从而大大缩短农药的创制周期,满足对速度竞争的要求。  相似文献   

17.
The past 30 years have witnessed a period of significant expansion in the use of halogenated compounds in the field of agrochemical research and development. The introduction of halogens into active ingredients has become an important concept in the quest for a modern agrochemical with optimal efficacy, environmental safety, user friendliness and economic viability. Outstanding progress has been made, especially in synthetic methods for particular halogen‐substituted key intermediates that were previously prohibitively expensive. Interestingly, there has been a rise in the number of commercial products containing ‘mixed’ halogens, e.g. one or more fluorine, chlorine, bromine or iodine atoms in addition to one or more further halogen atoms. Extrapolation of the current trend indicates that a definite growth is to be expected in fluorine‐substituted agrochemicals throughout the twenty‐first century. A number of these recently developed agrochemical candidates containing halogen substituents represent novel classes of chemical compounds with new modes of action. However, the complex structure–activity relationships associated with biologically active molecules mean that the introduction of halogens can lead to either an increase or a decrease in the efficacy of a compound, depending on its changed mode of action, physicochemical properties, target interaction or metabolic susceptibility and transformation. In spite of modern design concepts, it is still difficult to predict the sites in a molecule at which halogen substitution will result in optimal desired effects. This review describes comprehensively the successful utilisation of halogens and their unique role in the design of modern agrochemicals, exemplified by various commercial products from Bayer CropScience coming from different agrochemical areas. Copyright © 2009 Society of Chemical Industry  相似文献   

18.
The global agrochemical market in 1991 was $26800 million, yet biological products were reported to account for only $120 million of sales per annum—less than 0.5 % of the total. The majority of these sales are attributed to bio-insecticides of which Bacillus thuringiensis accounts for over 90%, but B. thuringiensis could be described as a biologically produced insecticide, rather than a true biocontrol agent. Biological products have technical limitations, including extreme specificity, sensitivity to environmental factors and problems with robustness of the formulations, but ironically, it is these limitations which also give biological control an image of environmental acceptability. Nonetheless, some of the limitations will be overcome and sales will increase, but primarily in niche situations such as the control of soil-borne diseases and the control of insect pests showing resistance to agrochemicals. In order for significant inroads to be made into such niche markets it is imperative that progress with biological products is not impaired by over-regulation, and a rational approach by all regulatory bodies is required. Overall, though, agrochemicals are likely to continue to be the major method of crop protection for the foreseeable future, and the biological control field now needs clear, well-defined goals if current successful niche products can be the basis for future success rather than a limited experiment in alternative technology.  相似文献   

19.
农药隐性成分现状、危害、检测技术及管理措施   总被引:1,自引:0,他引:1  
农药隐性成分主要是指农药制剂中人为添加标称有效成分以外的农药。本文综述了农药隐性成分的现状、危害、检测技术和管理措施,为降低我国农产品的重大安全隐患和农药的质量管理和控制提供技术参考。  相似文献   

20.
Natural compounds and living organisms continue to play a limited role in crop protection, and few of them have reached the market, despite their attractiveness and the efforts made in research. Very often these products have negative characteristics compared to synthetic compounds, e.g., higher costs of production, lower effectiveness, lack of persistence, and inability to reach and penetrate the target plant. Conversely, nanotechnologies are having an enormous impact on all human activities, including agriculture, even if the production of some nanomaterials is not environmentally friendly or could have adverse effects on agriculture and the environment. Thus, certain nanomaterials could facilitate the development of formulated natural pesticides, making them more effective and more environmentally friendly. Nanoformulations can improve efficacy, reduce effective doses, and increase shelf‐life and persistence. Such controlled‐release products can improve delivery to the target pest. This review considers certain available nanomaterials and nanotechnologies for use in agriculture, discussing their properties and the feasibility of their use in sustainable crop protection, in particular, in improving the effectiveness of natural bio‐based agrochemicals. © 2019 Society of Chemical Industry  相似文献   

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