修水县桑树主要病虫害监测与防控体系建设预案

通过借鉴外地经验,组建专业测报队伍,健全测报体系,确定调查对象,规范测报方法,建立和完善修水县桑树主要病虫害监测与防控体系,以保障蚕桑生产的安全。     

Adjuvants and herbicidal efficacy – present status and future prospects

The influence of adjuvants on spray liquid behaviour and herbicide performance is reviewed. Total formulation efficacy can be expressed as a function of [deposition:retention:uptake: translocation:a.i. toxicity]. Adjuvants influence the physico-chemical and plant interactions involved for each factor. Deposition efficiency of spray droplets on to a target is dependent largely on the droplet spectrum, whereas retention performance is dependent on plant leaf surface character, orientation and canopy architecture, as well as droplet volume, velocity and dynamic surface tension effects. Uptake into plant foliage is affected by the leaf surface wax, cuticle age and composition and species variability. Uptake can be improved through appropriate formulation to provide either stomatal infiltration or much greater and faster cuticular absorption of the active ingredient. The inherent translocation capability of the a.i. is not affected directly by adjuvants, which are relatively immobile, but they can increase the mass of absorbed a.i. translocated, as a consequence of improved uptake or may reduce it as a result of localized contact phytotoxicity. Considerable progress has been made in developing models of spray droplet deposition, adhesion and retention, as well as uptake. In future, individual models may be combined to provide an integrated formulation efficacy decision support system.     

Comparative effects of the herbicide dinitro-o-cresol on mitochondrial bioenergetics

The herbicide dinitro-o-cresol (DNOC) was evaluated for its effects on bioenergetic activities of potato tuber mitochondria to elucidate its mechanism of action and to compare its toxicological properties with those of the chemically related uncoupler dinitrophenol (DNP). DNOC acts as a typical uncoupler, similarly to the classical uncouplers DNP and carbonylcyanide p-trifluoromethoxyphenyl-hydrazone (FCCP). Low concentrations of DNOC (<100 μM ) maximally stimulate succinate-supported respiration of plant mitochondria, with simultaneous collapse of trans-membrane electrical potential, more efficiently than DNP. The herbicide makes the plant mitochondrial membrane more permeable to protons, acting as a protonophore even in non-energized mitochondria. High concentrations of DNOC (>100 μM ) act also more efficiently than DNP simultaneously as a protonophore and inhibitor of respiration, especially when respiration is supported by substrates that are transported to the matrix. The efficiency of DNOC is decreased with increase of mitochondrial protein, BSA and exogenous orthophosphate. Although similar effects were observed for animal and plant mitochondria, rat-liver mitochondrial respiration was more sensitive to DNOC than plant mitochondria. Furthermore, in the presence of DNOC, liver mitochondria exhibited a higher state 3 respiratory coupling level than potato tuber mitochondria, as a result of a considerable stimulation (60%) of state 3 respiration. In conclusion, DNOC is a more potent mitochondrial uncoupler and respiratory chain inhibitor than DNP, although their chemical structures are very similar. Apparently, the additional methyl group of DNOC increases its efficiency as an uncoupler and as an inhibitor, as compared to DNP. Plant mitochondria were shown to be as useful as animal mitochondria in evaluating the toxicity of these xenobiotics. © 1998 Society of Chemical Industry.     

Laboratory and field tests of spray-dried and granular formulations of a Bacillus thuringiensis strain with insecticidal activity against the sugarcane borer

Formulations of Bacillus thuringiensis Berliner (Bt) with insecticidal activity against the sugarcane borer, Diatraea saccharalis Fabricius (Lepidoptera: Pyralidae), were developed and tested under laboratory and field conditions. The formulations were prepared using biodegradable polymers such as modified corn starch as an encapsulating agent, gelatin as an adherent, powdered sugarcane as a feeding stimulant and a Bt var. kurstaki GM-34 strain from a non-sugarcane region as the active ingredient. The spore-crystal complex of this strain was mixed at three different concentrations (30, 70 and 100 g kg(-1)) with the other ingredients. The blends were prepared as spray-dried and granular formulations, and then submitted to laboratory tests with two day old larvae of D. saccharalis and field tests in sugarcane crops with natural sugarcane borer infestation. Spray-dried formulations in laboratory bioassays caused mortality near 100% with all three concentrations, and granular formulations caused mortality around 84%. The field tests showed that spray-dried formulations at 70 and 100 g kg(-1) concentrations were as effective as a commercial bioinsectide (Lepinox), while granular formulations were ineffective.     

内生短短芽胞杆菌011可湿性粉剂的研制

以植物内生短短芽胞杆菌011为研究对象,通过对载体、润湿剂、分散剂、稳定剂、保护剂的筛选,确定了内生短短芽胞杆菌011可湿性粉剂最佳配方：滑石粉10%,木质素磺酸钙7%,DBS 3%,CMC-Na 2%,糊精0.1%。结果显示制备的短短芽胞杆菌011可湿性粉剂在25 ℃室温下芽胞含量为1. 8×1010 cfu/g,pH 6.8,悬浮率76%,润湿时间52s,细度通过率98%。能有效降低化学农药在农业生产中的使用率,减少农药对生态环境的破坏。     

Response of the subterranean termite Coptotermes formosanus (Isoptera: Rhinotermitidae) to soil treated with microencapsulated fenobucarb

BACKGROUND: Treating soil with insecticides is thought to be an effective method for termite control. Speed of action and repellency of insecticides are important factors for discussing their barrier effects as soil-treatment termiticides. The chemical barrier effect of microencapsulated fenobucarb against Coptotermes formosanus Shiraki was examined in the laboratory.RESULTS: Fenobucarb had a significantly faster lethal effect when applied to the mouthparts than to the tergites of worker termites. Soil that had been treated with > or = 50 mg kg(-1) of microencapsulated fenobucarb had a barrier effect within a single day, and could stop or retard the penetration of termites for 7 days. Microencapsulated fenobucarb did not act as a repellent, as indicated by a gradual increase in mortality at > or = 50 mg kg(-1) with slight penetration into the treated soil during the 7 day test.CONCLUSION: The results suggest that microencapsulated fenobucarb is a fast-acting termiticide, with a good barrier effect as a soil treatment, that also acts as a reduced repellent, retarding entry of termites into treated soil.     

抗病性持久度的估测(Ⅱ)——小麦条锈病抗病性持久度的模拟研究

 以小麦条锈病大区流行模型PANCRIN为基础,建成该病抗病性持久度模型PANCVDE,进行模拟试验,结果指出,除供试垂直抗病性品种本身的抗小种谱、种植面积和气候条件制约的流行速率三者综合为抗病性丧失的主导因素外,背景系统中其它多种因素也都程度不同地影响着甚至制约着抗病性丧失,如感病品种的面积、水平抗病性品种的面积、其它垂直抗病性品种的抗小种谱、垂直抗性水平抗性综合抗病性品种、新小种的侵袭力等等。模拟结果大都能被已有认识或经验所接受,其中有些还暗含一些启示,如新小种定向选择压力的定量化估测、水平抗病性对垂直抗病性的保护作用、和小种侵袭力研究的重要性等。作者认为,系统模拟方法可以用于小麦条锈病以及类似病害的品种抗病持久度研究。     

Antifeeding effect of cypermethrin and permethrin at sub-lethal levels against Pieris brassicae larvae

An antifeeding (feeding deterrent) response by first- and fifth-instar larvae of Pieris brassicae was shown to be significant at sub-lethal levels of cypermethrin and permethrin, using leaf-discs treated with the pyrethroids by dipping. Permethrin was slightly more effective than cypermethrin both as an insecticide and as an antifeedant against fifth-instar larvae, but the reverse order of effectiveness was observed, with a marked difference in mortality, against newly-hatched larvae. When 1-day-old fifth-instar larvae were continuously given leaf discs treated with a solution of the pyrethroid (1 mg litre^?1), up to the time of pupation, both cypermethrin and permethrin induced a significant extension of the larval period, with a reduction in the maximum larval and pupal weights, as well as a reduction in the total leaf-area consumed. However, at higher levels of both pyrethroids, lowering the temperature induced some irritancy, as indicated by regurgitation and frequent uncoordinated wriggling movements of the fifth-instar larvae. The advantages of cypermethrin as a protectant and as an antifeedant over permethrin are discussed.     

Recent development in suspoemulsions

Suspension emulsions or suspoemulsions result from the combination of an emulsion phase, containing one or more active ingredients, with a continuous phase also containing active ingredients but in the form of a solid dispersion. Advantages of such products, which can contain as many as four complementary biologically active ingredients, are elimination of tank mixing; a reduced inventory of products; reduction in the number of applications to a given crop; and savings in time and money. The development of suspoemulsions is discussed and a novel, easy method for their preparation, using latexes, is described. Such products are also useful as feedstock emulsions for other suspension emulsions as well as constituting a stable oil-in-water emulsion delivery system in their own right.     

Molecular characterization of Endothia gyrosa isolates from Eucalyptus in South Africa and Australia

Endothia gyrosa is a canker pathogen best known as the causal agent of pin oak blight in North America, and causes cankers on other woody hosts such as Castanea spp. and Liquidambar spp. In South Africa, Australia and Tasmania, a fungus identified as E. gyrosa has been recorded on Eucalyptus spp. Some morphological differences exist between the North American fungus and the isolates from Eucalyptus . Phylogenetic relationships between E. gyrosa from North America and E. gyrosa from South Africa and Australia, as well as that of the related fungi Cryphonectria parasitica and C. cubensis , were studied using PCR-based restriction fragment length polymorphism (RFLP) and sequences of the internal transcribed spacer (ITS) region of the rRNA operon. Endothia gyrosa isolates from South Africa produced the same RFLP banding patterns as those from Australia, which differed markedly from North American isolates of E. gyrosa . In a phylogram based on the DNA sequences, the Australian and South African isolates of E. gyrosa resided in a single, well resolved clade, distinct from North American isolates. Isolates of C. parasitica grouped in the same clade as the South African and Australian isolates of E. gyrosa , but C. cubensis was distantly related to them. The molecular data suggest that the E. gyrosa isolates from South Africa and Australia represent a distinct taxon, and probably belong to the genus Cryphonectria .     

塔里木盆地水资源开发与环境保护分析

针对塔里木盆地资源环境的特点和水资源开发利用的现状，分析了该地区水资源开发利用中存在的问题，探讨了干旱区水资源开发利用与经济发展以及环境保护之间的关系，提出了水资源开发利用与环境保护相应对策，从而为本区水资源合理开发利用以及环境保护提供决策帮助，并为我国西部资源开发和生态保护提供参考。     

我国辐照检疫处理的研究现状

辐照检疫处理是继化学熏蒸处理之后兴起的一种物理处理技术,将其用作水果检疫处理已成为一种国际趋势.本文主要概述了我国辐照检疫处理的研究现状,旨在为进一步推动辐照检疫处理的商业化运作提供技术参考.     

Determining the most effective concentration of cypermethrin and the appropriate carrier particle size for fire ant (Hymenoptera: Formicidae) bait

BACKGROUND: The purpose of this study was to determine the most effective particle size of DDGS (distiller's dried grains with solubles) as fire ant bait carrier, as well as the most effective concentration of cypermethrin as a toxicant against the red imported fire ant (RIFA) Solenopsis invicta Buren under laboratory conditions. RESULTS: The DDGS particle size did not affect the fire ant's preference for the bait, but it did affect the mass of DDGS being carried back to the nest. The size of the DDGS particles and the mass of DDGS being carried back to the nest were positively correlated. The most efficient particle size of DDGS was 0.8–2 mm. The concentration of cypermethrin has a specific range for killing fire ants in an efficient manner. Neither a very low nor a very high concentration of cypermethrin was able to kill fire ants efficiently. The most effective concentration of cypermethrin was 0.13% in DDGS when mixed with 15% shrimp shell powders and 11% soybean oil. CONCLUSION: Based on its ability to kill fire ants when mixed with cypermethrin, as well as the advantage of having a larger area coverage when sprayed in the field, DDGS as the carrier and cypermethrin as the toxicant can be considered to be an efficient way to prepare fire ant bait for controlling fire ants in infested areas. Copyright © 2012 Society of Chemical Industry     

农药新剂型——微乳粒剂配制的可行性研究

以三唑磷为模式农药,研究了一种外观为颗粒状、用水稀释后成微乳液的农药新剂型——微乳粒剂配制的可行性。以乳状液的中位径(D50)为因变量,各表面活性剂用量为自变量,采用混料均匀试验设计并结合偏最小二乘回归法筛选表面活性剂品种;用比例法与对分法优化各表面活性剂用量;采用旋转挤压造粒法造粒。将筛选获得的农乳500与农乳602号用于配制15%三唑磷微乳粒剂,其乳状液外观为淡蓝色透明状,分散相颗粒迁移速度为0,且不同水质(水硬度:0~3 420 mg/L,水温:10~50 ℃)下乳液稳定性均合格;乳状液D50为54.2 nm,粒径分布范围为15.7~122 nm,粒径增大速率为0.01%/min;乳状液在相对离心力10 730×g下离心5 min未发生相分离。结果表明:该三唑磷微乳粒剂的乳状液为微乳液,微乳粒剂可以成功配制。     

Potential and actual uses of zeolites in crop protection

In this review, it is demonstrated that zeolites have a potential to be used as crop protection agents. Similarly to kaolin, zeolites can be applied as particle films against pests and diseases. Their honeycomb framework, together with their carbon dioxide sorption capacity and their heat stress reduction capacity, makes them suitable as a leaf coating product. Furthermore, their water sorption capacity and their smaller particle sizes make them effective against fungal diseases and insect pests. Finally, these properties also ensure that zeolites can act as carriers of different active substances, which makes it possible to use zeolites for slow‐release applications. Based on the literature, a general overview is provided of the different basic properties of zeolites as promising products in crop protection. © 2015 Society of Chemical Industry     

植物病害时空流行动态模拟模型的构建

 一个描述在二维空间中单一种植或混合种植的植物群体内病害时、空流行动态的计算机随机模拟模型构建完成。模型由寄主、病原2个组分和病斑产孢、孢子传播、孢子着落、孢子侵染、病斑潜育、寄主生长、病害控制等一系列代表病害流行生物学过程的子模型构成。模型采用了面向对象的程序设计方法,用C++语言编写,能以病害流行曲线图、空间分布图、数据列表等方式显示模拟结果。测试结果表明:模型能反映植物病害流行过程的本质规律,既可作为植物病害流行学教学工具,帮助学生理解病害流行的时、空动态规律和不同因子对病害流行的影响,也可以作为研究工具,对流行学的某些理论问题进行模拟研究     

Steady-state and transient analysis of integument penetration by insecticides

Insecticide penetration studies are usually done by applying a finite dose of material to a finite area of the integument in a solvent, such as acetone, that evaporates very quickly. The time-course of penetration is then measured either as the buildup of material inside the insect or as the decline of material recoverable in a surface wash. Pharmacokinetic models are often used to describe such experiments, but identical models can be formulated from diffusion theory. Diffusion theory was applied to obtain equations that describe the steady-state behavior of a single-layer integument with partitioning between integument and solutions, and a double-layer integument with partitioning between layers and between each layer and the adjacent solution. The steady-state flux equations for both models were first-order, and it was shown that this would be the case for steady-state flux through any number of layers. The steady-state analysis has two limitations. First, the assumption of a steady state implies that the concentration gradient across each layer of the integument is linear, and that this could not occur instantaneously. Second, the analysis assumes that material diffuses from a pool on the surface at some external concentration, whereas, ideally, it is applied as a plane source of infinite concentration. If the steady-state assumption is rejected, the diffusion equation can be solved exactly, using Green's function, for diffusion of a topically applied dose across the integument modeled as a homogeneous plate, if the concentration at the internal face is assumed to remain zero. An analytical expression is obtained for concentration as a function of time and position in the integument, and from it are calculated flux into the insect and disappearance of material recoverable in a solvent wash, where material is assumed to be recoverable to an arbitrary depth. For small values of recovery depth, recovery falls precipitously following application, then progressively more slowly as the experiment proceeds. This phenomenon has been seen in much published data, and is explained adequately for the first time by the theory presented here. Predicted flux into the insect rises with a delay and then falls, but its fall is not exponential, as is often assumed. Peak flux is predicted to be directly related to the diffusion coeficient. The impact of these results on the design of penetration experiments is discussed.     

芹菜细菌性软腐病病原的分离与鉴定

 由植物病原细菌引起的芹菜软腐病在北京地区普遍发生,其中以顺义及通州区县较为严重。自发病芹菜茎段中分离细菌,通过接种芹菜进行致病性测定,确定了54个致病菌株。虽然菌株间致病力有一定的差异,但大多数菌株对芹菜致病力强。通过培养性状和菌体形态观察、生理生化反应和Biolog测定,结合胡萝卜软腐果胶杆菌Pectobacterium carotovorum 6个管家基因(pgi、rpoS、mdh、proA、mtlD、icdA)的基因扩增、序列测定和多基因联合系统发育分析,将病原菌鉴定为胡萝卜软腐果胶杆菌P. carotovorum的3个亚种。其中45个菌株为P. carotovorum subsp. odoriferum,频数为83.33%;6个菌株为P. carotovorum subsp. carotovorum,频数为11.11%;3个菌株为P. carotovorum subsp. brasiliensis,频数为5.56%。上述结果显示,北京地区芹菜细菌性软腐病的病原菌为胡萝卜软腐果胶杆菌P. carotovorum的3个亚种,其中以P. carotovorum subsp. odoriferum为优势种。     

星天牛生物防治研究进展

星天牛Anoplophora chinensis Forster为亚洲本土的林木钻蛀性害虫,近年来已入侵到一些欧洲国家,被列为重要的国际检疫对象。本文综述了国内外有关星天牛的自然天敌种类及其人工利用的研究进展。我国古代曾用黄猄蚁Oecophylla smaragdina Fabricius防治危害柑橘树的星天牛,近年来开展了野外释放天敌昆虫花绒寄甲Dastarcus helophoroides Fairmaire成虫和卵卡防治星天牛的实践,都取得了较好的防治效果。川硬皮肿腿蜂Sclerodermus sichuanensis Xiao对星天牛低龄幼虫具有一定的控制作用,天牛卵长尾啮小蜂Aprostocetus fukutai Miwa&Sonan显示出了良好的生物防治利用前景,在意大利对星天牛的卵寄生率最高达72%。一些欧洲本地拟寄生蜂种类,如柄腹茧蜂Spathius erythrocephalus Wesmael也可寄生入侵当地的星天牛自然种群。此外,利用昆虫病原微生物控制星天牛,也具有较好的防治前景,如用布氏白僵菌Beauveria brongniartii Petch制成的无纺布菌条已经在日本开发成为一种商品,真菌侵染可引起天牛高致死率。昆虫病原线虫夜蛾斯氏线虫Steinernema feltiae Filipjev和小卷蛾斯氏线虫S.carpocapsae Weiser也具有作为生物杀虫剂用于控制星天牛幼虫的开发前景。本文还讨论了目前星天牛生物防治中存在的不足及其原因,展望了今后研究的重点和方向。     

棉铃虫性信息素生物合成研究进展

性信息素是昆虫两性通讯的化学信号, 在物种繁衍中担当着重要的角色。以性信息素为基础的害虫诱杀和交配干扰等防治手段具有灵敏度高、选择性强、对天敌安全、不污染环境等优点, 在害虫综合治理和绿色防控体系应用中深受青睐。棉铃虫 Helicoverpa armigera 是一种世界性农业害虫, 具有适应能力强和寄主广泛的特点, 条件适宜时常大面积暴发成灾。以棉铃虫为代表的醛类性信息素的生物合成和调控过程, 是目前研究较早也较为透彻的一类性信息素。本研究概述了棉铃虫性信息素的组分和功能, 生物合成时的信号转导途径和调控机制, 以及性信息素前体的生成和特异性组分的碳链修饰过程, 并总结了当前研究的不足, 旨在为今后的基础研究和生产应用提供指导。