浅议农药术语的标准化问题

术语标准是重要的基础标准,正确使用标准术语是实现有效交流的前提和保证。本文介绍了术语的基本概念、国内外术语标准化概况,并就农药术语标准化现状,阐述了加强我国农药术语标准化工作的重要性和必要性。     

榆树死亡的原因分析

针对2010年春季的异常天气,对榆树的发芽、出叶情况进行跟踪调查,简要分析开春榆树"集体休眠"和部分死亡的原因。     

大棚蘑菇死亡的原因与管理注意事项

在大棚蘑菇出菇中,常会遇到蘑菇死亡的情况,笔者介绍蘑菇死亡的原因及管理注意事项。1大棚蘑菇死亡的原因蘑菇出菇阶段常会出现小菇萎缩、变黄而死亡,主要原因有如下几个方面:1.1持续高温出菇阶段气温高于23℃连续3d以上,菌蕾生长受到温     

春小麦碳同位素分辨率与相关生理性状的遗传相关分析

用17份春小麦品种作为试验材料,在宁夏灌区银川测定碳同位素分辨率(△)、水分利用效率 (WUE)、灰分、比叶重、光合气体交换参数,并在方差分析显著的基础上,进行遗传、表型和环境相关分析和简单相关分析.结果表明:各性状在品种间存在显著或极显著差异 .△Gm与Sm、WUE、maL、 Ci、Gs、Ci/Ca均呈极显著正遗传相关,与开花期Pn及灌浆期Tl呈显著负遗传相关;△S m与WUE、maL、开花期气体交换参数(Ci、Gs、Ci/Ca)的遗传相关性达到极显著正相关水平,与Tl、开花期Pn的遗传相关达到极显著负相关水平,并且它们之间的遗传相关主要受遗传基因的控制,环境条件对其相关性影响较小,maL与△的显著的遗传相关,作为△的替代指标有较大的潜力,认为在灌区适合种植和培育高秆型、高碳同位素分辨率型和低温型小麦.     

乙烯信号参与调控水稻纹枯病抗性的研究

 乙烯(ET)信号在植物抵抗各种逆境反应中具有重要作用,但目前关于乙烯信号在调控水稻纹枯病抗性中的作用仍缺乏系统研究。本研究以感纹枯病水稻品种Lemont和抗纹枯病水稻品种YSBR1为材料,分析了纹枯病菌接种后乙烯合成关键基因及信号传导途径中标志基因的表达水平,结果显示,纹枯病菌侵染可显著诱导相关基因的表达、激活乙烯信号。进一步采用乙烯合成抑制剂和信号激活剂处理水稻并进行接种鉴定,结果显示,两种化学剂分别可抑制或激活乙烯信号;无论是Lemont还是YSBR1,激活其乙烯信号均可显著增强抗病性,而抑制该信号均显著降低抗病性。对3个乙烯受体突变体(ethylene response2, etr2; ethylene response3, etr3; ethylene response sensor2, ers2)进行温室接种鉴定,发现突变体的病斑长度均极显著高于野生型对照。以上研究表明乙烯信号在水稻对纹枯病菌的防卫反应或基础抗性中具有十分重要的作用,结果将为进一步解析“水稻-纹枯病菌”间的互作机制、制定合适的病害综合防控策略提供理论基础。     

拟南芥的抗病信号传导途径

 拟南芥是研究植物与病原物相互作用的模式植物。植物感病和抗病取决于病原物无毒基因产物和寄主抗病基因产物的识别,以及随后的相关防卫反应的激活。在拟南芥的抗病过程中,水杨酸、茉莉酸、乙烯等信号分子都不同程度地参与着抗病过程中的不同环节,起着非常重要的作用。由于这些信号分子在对不同病原菌的抗性中的作用存在差异,因而将抗病信号传导分为依赖于水杨酸和依赖于茉莉酸/乙烯的途径。本文将着重讨论这些信号分子在植物系统获得抗性以及诱导系统抗性中的作用。     

葡萄感染霜霉病菌后几种信号物质的变化

以3个抗病性不同的酿酒葡萄品种(‘西拉’‘霞多丽’‘赤霞珠’)叶片为材料,检测霜霉病菌侵染后几种病原相关信号物质,如脱落酸(ABA)、过氧化氢(H2O2)、一氧化氮(NO)、茉莉酸(JA)和乙烯(ETH)等的变化,以探讨葡萄抵御霜霉病菌的信号转导机制。结果表明,H2O2和NO是葡萄感应霜霉病菌的早期信号分子,且抗性较强的品种‘西拉’的变化最为明显;JA和ABA是抗性较差品种‘赤霞珠’应答霜霉病的信号组分。而3个抗性不同葡萄品种的乙烯变化无明显差别。推测H2O2、NO、JA和ABA均参与了葡萄对霜霉病菌的防御反应,但不同品种间信号转导组分可能存在差异。     

植物对土壤干旱信号的感知、传递及其水分利用的控制

本文对植物感和土壤干旱信号,传递及其水分利用控制做了综述,讨论了木质部汁液中ＡＢＡ浓度,蛋白质和ＰＨ值的变化,并对ＡＢＡ是否属唯一信号做了论述,介绍了由此理论设计的根据系分区交潜灌溉原理及其节水效益。     

病原细菌受体介导的c-di-GMP信号传导及其调控机制

细菌第二信使环二鸟苷酸(c-di-GMP)信号网络系统主要涉及信号代谢、识别、接受、传递、功能表达和调控。c-di-GMP胞内水平受到鸟苷酸环化酶(DGC)和磷酸二酯酶(PDE)的控制。c-di-GMP信号受体类型多样,包括转录调控因子、PilZ结构域蛋白、退化的GGDEF和EAL结构域蛋白、核糖体开关、多核苷酸磷酸化酶和新发现的蛋白激酶等。c-di-GMP受体接受信号后,可以在转录、翻译以及翻译后水平上对下游靶标进行调控,从而影响细菌的毒性、运动性、生物膜形成、细胞分裂等生理生化过程。本文结合本实验室对水稻白叶枯病菌的研究结果,综述了近年来国内外在c-di-GMP信号受体介导的调控机制等方面的研究进展。     

Mosquito repellents: a review of chemical structure diversity and olfaction

Research on mosquito chemical repellents continues to advance, along with knowledge of mosquito olfaction and behavior, mosquito–host interactions and chemical structure. New tools and technologies have revealed information about insect olfactory mechanisms and processing, providing a more complex approach for the interpretation of how chemical repellents influence host‐seeking and feeding behavior. Even with these advances, there is still a large amount of information contained in the early works on insect repellents. Many of the standard test methods and chemicals that are still used for evaluating active repellents were developed in the 1940s. These studies contain valuable references to the activity of different structural classes of chemicals, and serve as a guide to optimization of select compounds for insect repellency effects. Copyright © 2010 Society of Chemical Industry     

利用化学激发子防控作物害虫研究进展

诱导防御反应是植物抵御害虫为害的一种重要机制。在这一防御机制中,各种化学激发子,包括植食性昆虫相关分子模式、植物激素及其类似物、植物激发子多肽等发挥着重要作用。合理开发利用这些化学激发子,可望帮助植物建立一种天然的防御体系,从而降低害虫种群密度、减轻害虫为害,减少化学农药使用量。本文将主要对诱导植物抗虫性的化学激发子的最新研究成果进行概述,并展示利用化学激发子防控田间作物害虫的最新研究案例,提出亟待解决的问题,以促进化学激发子在作物害虫防控中的应用。     

Surfactants in plant disease management: A brief review and case studies

In plant disease management, surfactants are generally used in combination with pesticides to facilitate delivery of the pesticide chemicals to the target sites in plants, vectors, or pathogens. Their intended use is rarely for direct effect on plant pathogens. However, trends in recent studies have revealed an appreciable increase in their use for direct management of plant diseases. In this paper, we briefly review the progress made in the use of surfactants for disease management, as adjuvants and when applied for direct effect. We carried out experiments to evaluate the effect of selected synthetic surfactants (Cohere, Kinetic, Silwet-77, and Induce) on powdery mildew in squash and bacterial spot in tomato. Results from this study showed that the effect of surfactants on these pathogens is dependent on the type of plant pathogen or disease. All tested surfactants exhibited in vitro bactericidal activity against Xanthomonas perforans, a causal pathogen of bacterial spot of tomato. In the greenhouse, Cohere significantly reduced disease severity of powdery mildew in squash compared to the untreated control. Cohere also showed promise in field trials against bacterial spot of tomato, but the other surfactants tested promoted this disease. Our studies demonstrate the importance of evaluating surfactants for their use in management of plant diseases both for direct effect and as adjuvants in tank mix.     

Sudden oak death: geographic risk estimates and predictions of origins

Ecological niche modelling techniques were applied to address the questions of the origins and potential geographic extent of sudden oak death, caused by the pathogen Phytophthora ramorum . Based on an ecological niche model derived from the phytopathogen's California distribution and distributions of potential host species, it was determined that the disease has high potential to colonize the southeastern United States, and that its likely source area is eastern Asia.     

拟南芥BOI 基因在抗氧化胁迫和细胞死亡中的功能分析

 本文利用BOI(Botrytis Susceptible 1 Interactor)基因敲减(knock-down) 株系、过量表达株系以及烟草瞬时表达系统,研究了BOI 基因在细胞程序化死亡(PCD)中的作用以及BOI 蛋白中RING 和WRD 结构域的功能。结果表明,BOI 基因的表达下调导致抗氧化胁迫能力下降,弱化了对活性氧介导的PCD 抑制作用;BOI 过量表达或瞬间表达可以增强对活性氧介导和α-吡啶甲酸诱导的PCD 的抑制作用。进一步研究发现,BOI 蛋白中的RING 结构域是BOI 抑制PCD 所必需的,WRD 结构域与BOI 对PCD 的抑制作用关系不大。     

Control of blackleg and tuber soft rot of potato caused by Pectobacterium and Dickeya species: a review

This paper briefly reviews research on the causative agents of blackleg and soft rot diseases of potato, namely Pectobacterium and Dickeya species, and the disease syndrome, including epidemiological and aetiological aspects. It critically evaluates control methods used in practice based on the avoidance of the contamination of plants, in particular the use of seed testing programmes and the application of hygienic procedures during crop production. It considers the perspective of breeding and genetic modification to introduce resistance. It also evaluates the application of physical and chemical tuber treatments to reduce inoculum load and examines the possibility of biocontrol using antagonistic bacteria and bacteriophages.     

Neonicotinoid insecticides imidacloprid and clothianidin affect differently neural Kenyon cell death in the cockroach Periplaneta americana

The intracellular toxicity of the neonicotinoid insecticides imidacloprid and clothianidin was studied on cockroach Periplaneta americana Kenyon cells using the trypan blue exclusion test and the adenylate kinase (AK) detection reagent. To evaluate cytotoxicity, Kenyon cells were exposed to different concentrations (1, 5, 10, 50 and 100 μM) of both imidacloprid and clothianidin at different delays (1, 3, 5, 8 and 24 h). Our data show that both imidacloprid and clothianidin decreased cell viability, with a more pronounced effect following imidacloprid exposure. Indeed, a significant decrease of cell viability was observed for 50 and 100 μM imidacloprid at 8 and 24 h, with trypan blue exclusion test. Study of the AK activity revealed that 50 and 100 μM imidacloprid induced an increase of AK activity, except for 50 μM at 24 h whereas at the same concentrations, clothianidin induced a transient effect at 5 and 8 h. According to previous studies showing that imidacloprid was a partial agonist and clothianidin a full agonist of insect nicotinic acetylcholine receptors, we demonstrated that both imidacloprid and clothianidin were also able to induce distinct intracellular toxic effects.     

Two phases of intracellular reactive oxygen species production during victorin-induced cell death in oats

Reactive oxygen species (ROS) are thought to be involved in various forms of programmed cell death (PCD) in animal and plant cells. PCD, along with the production of ROS, occurs during plant–pathogen interactions. Here we show that victorin, a host-specific toxin produced by Cochliobolus victoriae, which causes victoria blight of oats, induces two phases of intracellular ROS production in victorin-sensitive oat mesophyll cells. The initial production of ROS is restricted at mitochondria and not accompanied with cellular oxidative damage. Later production of ROS is dispersed into cells concomitant with lipid peroxidation, chloroplast dysfunction, and cell death. Superoxide dismutase can clearly suppress the initial ROS production and delay the progression of cell death. These data indicate that the initial ROS production may be involved in the cell death induction process, and the later ROS production may play important roles in events leading to cellular disruption.     

水稻MKK10-2激酶可诱导烟草细胞死亡和活性氧产生

MAP kinase级联信号在植物生长发育、抗病和抗逆等进程中发挥重要作用。水稻OsMKK10-2基因受脱落酸、干旱、盐和冷胁迫诱导表达。酵母双杂和pull down实验表明OsMKK10-2能与下游激酶OsMPK1、OsMPK5和OsMPK6相互作用,且OsMKK10-2N端MPK停泊位点决定了其与下游MPKs间的互作。OsMKK10-2:GFP融合蛋白定位在烟草细胞质和细胞核。不过,较长时间表达OsMKK10-2可以导致烟草细胞死亡和ROS产生,且依赖于其N端的MPK停泊位点。研究结果为进一步揭示OsMKK10-2的生物学功能奠定了基础。