Evolving understanding of the evolution of herbicide resistance

A greater number of, and more varied, modes of resistance have evolved in weeds than in other pests because the usage of herbicides is far more extensive than the usage of other pesticides, and because weed seed output is so great. The discovery and development of selective herbicides are more problematic than those of insecticides and fungicides, as these must only differentiate between plant and insect or pathogen. Herbicides are typically selective between plants, meaning that before deployment there are already some crops possessing natural herbicide resistance that weeds could evolve. The concepts of the evolution of resistance and the mechanisms of delaying resistance have evolved as nature has continually evolved new types of resistance. Major gene target‐site mutations were the first types to evolve, with initial consideration devoted mainly to them, but slowly ‘creeping’ resistance, gradually accruing increasing levels of resistance, has become a major force owing to an incremental accumulation of genetic changes in weed populations. Weeds have evolved mechanisms unknown even in antibiotic as well as other drug and pesticide resistances. It is even possible that cases of epigenetic ‘remembered’ resistances may have appeared. Copyright © 2009 Society of Chemical Industry     

蔬菜蚜虫抗药性现状及抗性治理策略

蚜虫是为害蔬菜作物的一类重要害虫,如不防治会给蔬菜生产造成重大经济损失。长期以来主要依靠使用农药防治蔬菜蚜虫,但由于化学农药的不合理使用,蔬菜蚜虫对有机磷、拟除虫菊酯、氨基甲酸酯、新烟碱等多种类型的杀虫药剂均产生了不同程度的抗性。本文对常见的蔬菜蚜虫的抗药性现状、抗药性机理以及治理策略进行了论述,以期为该类害虫的可持续控制提供参考。     

Quantification of late blight resistance of potato using transgenic Phytophthora infestans expressing β-glucuronidase

A transgenic Phytophthora infestans strain that constitutively produces and secretes -glucuronidase (GUS) was used in detached leaf assays to quantify the levels of resistance to late blight in potato cultivars Surprise, Irene, Pimpernel, Alpha and Bintje. Four days after inoculation levels of GUS activity were determined in infected leaves. Significant differences between the various cultivars were observed. Discrimination between resistant and susceptible cultivars was possible based solely on levels of GUS activity. Regression analysis revealed a positive correlation between in planta GUS levels and field resistance expressed as Area under Disease Progress Curve (ADPC).     

西花蓟马抗药性研究进展

西花蓟马是世界范围内蔬菜和花卉上的重要害虫之一,使用化学药剂是防治西花蓟马的主要手段,目前西花蓟马已对有机氯、有机磷、氨基甲酸酯、拟除虫菊酯、阿维菌素和多杀菌素等多种杀虫剂产生了抗药性。本文从抗药性现状、抗性机制和抗性治理等几个方面介绍了国内外有关西花蓟马抗药性的研究进展。     

Non-target-site-based resistance to ALS-inhibiting herbicides in six Bromus rigidus populations from Western Australian cropping fields

BACKGROUND: Bromus rigidus is a common weed species that has increased in cropping fields owing to limited control options. During a random field survey in Western Australia, six B. rigidus populations that had survived in‐crop weed control programmes were collected. The study aimed to determine the resistance profile of these six populations. RESULTS: Based on dose–response studies, all six B. rigidus populations had a low‐level resistance to sulfosulfuron and sulfometuron (both sulfonylurea herbicides) while remaining susceptible to herbicides with other modes of action. ALS in vitro activity assays revealed no differences in enzyme sensitivity between susceptible and resistant populations, while the use of malathion (a cytochrome P450 inhibitor) in combination with sulfosulfuron caused the resistant populations to behave like the susceptible population. CONCLUSION: This study established that these six B. rigidus populations have a low‐level resistance to the ALS‐inhibiting sulfonylurea herbicides, but are able to be controlled by other herbicide modes of action. The low‐level, malathion‐reversible resistance, together with a sensitive ALS, strongly suggest that a non‐target‐site enhanced metabolism is the mechanism of resistance. Copyright © 2012 Society of Chemical Industry     

植物病原菌对杀菌剂多药抗性的发生现状

近年来, 随着杀菌剂在农作物病害田间防治中的大量使用, 植物病原菌的多药抗性(multidrug resistance, MDR)现象发生越来越普遍。本文综述了在草坪币斑病、灰霉病、小麦叶枯病和苹果青霉病等病害防治中, 病原菌对杀菌剂多药抗性发生的情况。以及在紫外诱导和杀菌剂离体驯化下, 致病疫霉Phytophthora infestans、立枯丝核菌Rhizoctonia solani、指状青霉Penicillium digitatum的多药抗性发生情况。分析了导致植物病原菌多药抗性产生的外排转运蛋白过表达、解毒酶代谢和靶标位点变化等相关机制, 并在此基础上提出了多药抗性预防和治理的策略, 以期为田间杀菌剂的高效利用, 延缓药剂的抗性风险提供科学参考。     

诱导水稻抗瘟性及诱抗机理研究进展

稻瘟病是危害水稻三大病害之首,水稻稻瘟病诱导抗病性具有持久性、广谱性、安全性、系统性等而对未来水稻稻瘟病的防治发挥巨大的作用。综述近年来国内外水稻诱导抗瘟性的研究进展,对生物及非生物诱导因子和诱导机理的三个方面进行了介绍,并提出对现在一些研究不足以及未来的发展方向。     

French vineyards provide information that opens ways for effective resistance management of Botrytis cinerea (grey mould)

Resistance to fungicides is an evolutionary process resulting from the selection of advantageous genotypes in naturally diverse populations. Seven fungicide modes of action are authorised to control grey mould caused by Botrytis cinerea on grapevine in France, and five of them have encountered specific resistance, with variable frequencies in populations and possible consequences for field fungicide efficacy. Moreover, multidrug resistance is caused by fungicide efflux and allows a weak resistance towards six unrelated modes of action. Here, a review is given of the fungicide resistance status of B. cinerea in France, particularly in the vineyards of Champagne, which are the most affected. Recently developed resistance and recent findings concerning the associated resistance mechanisms are focused upon in particular. Finally, antiresistance strategies are presented, and examples of managed resistance are discussed in a more general manner with the aim of extending this knowledge to other crops and countries undergoing similar resistance problems. © 2013 Society of Chemical Industry     

嘧菌酯在我国登记情况以及抗性研究现状

嘧菌酯是先正达公司于1997年上市的甲氧基丙烯酸酯类杀菌剂,它具有广谱、高效、安全的特点,自上市以来占有较大的市场份额。随着国外产品专利保护到期,我国掀起一阵注册热潮。但由于其作用为点单一,在使用过程中抗性问题日益严重。本文对嘧菌酯近年来登记情况、抗性发展研究状况、抗性产生机制以及治理措施进行了简要论述。希望为以后嘧菌酯的登记注册以及合理使用提供全面客观的依据。     

我国水稻田杂草抗药性研究进展

水稻是我国最主要的粮食作物之一,杂草的危害严重影响了水稻的产量与品质。化学防除仍然是治理水稻田杂草最有效的途径。目前我国水稻田稗属杂草、千金子、马唐、雨久花、野慈姑、异型莎草、耳叶水苋、眼子菜、节节菜、萤蔺等多种杂草对二氯喹啉酸、五氟磺草胺、氰氟草酯、噁唑酰草胺、苄嘧磺隆、吡嘧磺隆、双草醚、噁草酮、乙氧氟草醚等多种常用除草剂产生了抗药性。面对日趋严重的水稻田抗药性杂草的危害,对抗药性杂草进行深入系统的研究以达到科学防治的目的显得尤为重要。本文总结了我国水稻田抗药性杂草的抗药性水平、靶标酶抗药性机理、代谢酶抗药性机理和其他抗药性机理,归纳了抗药性杂草的交互抗性、多抗性发生情况以及抗药性治理现状,分析了我们在杂草抗药性研究与治理方面面临的问题。     

Herbicide‐resistant weed management: focus on glyphosate

This review focuses on proactive and reactive management of glyphosate‐resistant (GR) weeds. Glyphosate resistance in weeds has evolved under recurrent glyphosate usage, with little or no diversity in weed management practices. The main herbicide strategy for proactively or reactively managing GR weeds is to supplement glyphosate with herbicides of alternative modes of action and with soil‐residual activity. These herbicides can be applied in sequences or mixtures. Proactive or reactive GR weed management can be aided by crop cultivars with alternative single or stacked herbicide‐resistance traits, which will become increasingly available to growers in the future. Many growers with GR weeds continue to use glyphosate because of its economical broad‐spectrum weed control. Government farm policies, pesticide regulatory policies and industry actions should encourage growers to adopt a more proactive approach to GR weed management by providing the best information and training on management practices, information on the benefits of proactive management and voluntary incentives, as appropriate. Results from recent surveys in the United States indicate that such a change in grower attitudes may be occurring because of enhanced awareness of the benefits of proactive management and the relative cost of the reactive management of GR weeds. Copyright © 2011 Society of Chemical Industry     

Seedbank persistence,germination and early growth of glyphosate‐resistant Kochia scoparia

This study describes the seedbank persistence of glyphosate‐resistant (GR) Kochia scoparia at two sites in western Canada and examines if GRK. scoparia from western Canada and mid‐western United States (USA) differ from their susceptible counterparts in seed germination and early growth characteristics at low‐temperature regimes. Site or depth of seed burial (surface, 2.5 cm, 10 cm) did not affect seed viability over time and time to 50% and 90% loss of viability averaged 210 and 232 days respectively. Glyphosate‐resistant K. scoparia generally germinated later and had lower cumulative germination than glyphosate‐susceptible (GS) K. scoparia from Saskatchewan, Canada; and Kansas, USA; but not Colorado, USA. Similarly, time to 10% first leaf of GSK. scoparia from Saskatchewan and Kansas tended to be sooner than that of GRK. scoparia, with a greater percentage of GS vs. GR seedlings of populations from all regions having attained first leaf by the end of the experiment. The short seedbank longevity and delayed and reduced germination and time to first leaf of GRK. scoparia may potentially be exploited to maximise management efficacy through delayed preseeding weed control or alternatively by early seeding date to enhance crop competitiveness.     

植物抗病研究进展与展望

植物在其整个生活史中随时经受多种病原的侵袭,在进化过程中植物发展出多种对抗病原的机制。植物抗病性研究是当前植物病理学研究的热点问题之一。培育具有广谱而持久抗性的植物品种是育种学家追求的目标。目前,关于植物非寄主抗性、抗病基因介导的抗性、microRNA相关的抗性、感病基因的研究以及基因编辑在植物抗病性中的应用等方面已取得了大量新的研究成果。本文就以上几个方面综述了近年来植物抗病研究中的最新进展,并提出今后研究和育种中的应用展望。     

小麦持久抗性品种对中国条锈菌(系)抗病性特点的分析

小麦品种抗性谱鉴定、田间病情系统观察和抗性组分测定等结果表明,小麦持久抗条锈品种具显著的抗性特征,即成株期抗性谱很宽,有的品种甚至全生育期都表现抵抗,田间病情消长很慢且轻,成株期一般表现侵染机率低、病斑面积小、潜育期长。试验在控制条件下进行,便于操作,可用于小麦品种持久抗条锈性鉴定研究。     

城特232抗瘟性基因分析研究

用稻瘟病菌生理小种ZA49、ZB_1和日本鉴别菌系P—2b分析了城特232及其抗源亲本的抗性基因,并测定其等位关系。结果表明,城特289的抗性基因来自抗病亲本城堡1号(Toride 1)。它对3个小种(菌系)的抗性均受Pi-z′基因控制,而特特勃(Tetep)的抗性基因未导入到城特232中。本文还对抗病品种与抗源亲本之间抗性基因关系的推断及抗病品种的合理利用等进行了讨论。     

棉蚜抗药性现状及治理策略

棉蚜Aphis gossypii Glover是农业生产上最重要的害虫之一。化学杀虫剂一直以来都是棉蚜综合防治体系中的重要组成部分, 但化学杀虫剂的不合理使用导致棉蚜对多种杀虫剂均产生了高水平抗性。现有研究表明, 靶标位点突变、解毒酶基因的过表达以及某些肠道共生菌丰度的变化是导致棉蚜对杀虫剂产生抗性的主要机制。针对棉蚜抗性发展现状及其抗药性机制, 制定科学合理的抗性治理策略, 是充分发挥化学防治的优势、实现棉蚜可持续治理的关键。本文主要从棉蚜的抗药性现状、抗性机制和抗性治理策略3个方面对近10多年的主要进展进行了综述, 旨在为棉蚜抗药性长效治理和科学施策提供理论依据。     

粉虱类害虫抗药性研究方法综述

粉虱是世界上一类重要的害虫,随着化学杀虫剂的连续使用,其抗药性也日益严重。本文对粉虱类害虫的抗药性监测、机理及风险评估方法进行了综述,旨在对粉虱抗药性工作能提供一定的帮助。     

主要农业害虫对茚虫威的抗性现状及其治理策略

茚虫威属于噁二嗪类杀虫剂，与大多数杀虫剂不同的是其进入害虫体内需要经活化代谢转变成N-去甲氧羰基代谢物（decarbomethoxylated metabolite，DCJW）后不可逆地阻断钠通道，进而发挥杀虫活性。茚虫威由于其作用机制不同于常见的使钠离子通道延迟关闭的菊酯类药剂而被广泛用于鳞翅目和一些同翅目、鞘翅目害虫的防治。抗药性是任何杀虫药剂使用后面临的问题，茚虫威也不例外，许多害虫对其产生了不同程度的抗性。昆虫对茚虫威产生抗性的机制包括酯酶活性、谷胱甘肽S-转移酶（glutathione S-transferase，GST）和P450活性的增加以及分子靶标F1845Y、V1848I、L1014P的突变，这些对茚虫威抗性机制的研究基本都是基于抗性种群和敏感种群开展的，需要进一步验证其对抗性研究的贡献度。针对我国田间害虫种群对茚虫威的抗性现状，及时实施对茚虫威有效的抗性治理是迫切的。对于茚虫威的抗性治理除了传统的杀虫药剂轮用、混用外，需要利用其作用机制特点开展抗性治理策略研究。一是充分利用其活化代谢的特点，开展组合药剂的研究应用；二是菊酯类药剂和茚虫威的作用机制均与钠离子通道有关，但是前者是使钠离子通道关闭延迟，而后者是阻断钠离子通道，开展相关基础研究，使菊酯类药剂与茚虫威合理地用于抗性治理中。本文综述了茚虫威的抗性现状、抗性机制与交互抗性、茚虫威的抗性风险评价，针对茚虫威的抗性特点提出了抗性治理策略。