湖北省白肋烟病毒病调查及其鉴定

１９９５～１９９６年调查表明,湖北省五峰、建始、恩施县（市）白肋烟主产区为花叶和黄花病毒病流行区。１９９５年花叶类型发病率为１０％～９０％,平均３０％以上;黄化类型１０％～３０％,平均２０％左右,蚀纹病在３县（市）零星发生。１９９６年各产区病害比１９９５年轻,以花叶病害为主。经血清鉴定明确,花叶类型病害、黄化类型病害和蚀纹病分别由黄瓜花叶病毒（ＣＭＶ）、马铃薯Ｙ病毒（ＰＶＹ）和烟草花叶病毒（ＴＭＶ）引起。ＣＭＶ为侵染白肋烟的主要病毒。这是湖北省白肋烟病毒病调查与病毒鉴定的首次报道。     

白菜孤丁病毒一个枯纹株系的鉴定

1962年春开始,对本所試驗地大白菜采种株上呈現花叶并有枯紋症状的病株毒原(62—4号)进行鑑定研究。 1.寄主反应及症状:人工接种7科14属25种和品种的植物。結果可侵染十字花科、茄科、菊科、藜科及莧科19种和品种的植物,并表現不同的症状反应: (1)花叶症及枯紋:接种大白菜后十天左右,在接种叶上呈現不甚明显的褪綠暈斑,随后新生幼叶皺縮,明脉及褪綠花叶。在中外层較老的病叶上常呈現淡黄色綫条状或折綫形枯紋,或多角形、不規則形的枯斑。在蘿卜、油青菜、花椰菜及芥菜上也产生相似的褪綠花叶症、枯紋或枯斑。 (2)花叶症:接种甘蓝后不久,开始叶脉变黄,叶片呈褪綠黄点状花叶,后变成黄綠色斑块。叶脉縮短,叶片皺縮。症状較孤丁1号严     

黄花菜病害发生规律与防治技术

黄花菜属百合科植物,其花是一种特种蔬菜,鲜食、干食均可,栽培管理得好,可增产增收.常见的病害有：黄花叶斑病、黄花叶枯病、黄花锈病等10多种病害,发病严重而得不到有效防治时将造成毁灭性灾害.     

大豆病毒病的类型及其病原鉴定

东北地区发生的大豆病毒病,其症状主要为黄斑花叶、顶枯、皱缩花叶及卷叶等类型。根据对50个毒株测定的结果,这些病害的病原均属于大豆花叶病毒(SMV),但由于它们所引起的症状不同,可认为是三个不同的株系,即黄斑株系(SMV—Y,引起黄斑花叶和皱缩)、顶枯株系(SMV—T,引起顶枯)和卷叶株系(SMV—C,引起卷叶)。三个株系都由种子带毒传病,田间可由大豆蚜传染,属口针带毒型,只能系统侵染大豆及秣食豆,在菜豆品种家雀蛋上形成局部斑,不能侵染豇豆、眉豆、豌豆、普通烟、苋色藜等,在多种其他菜豆品种上无症。SMV—Y 的稳定性较低,失毒温度为50°～55℃,稀释限点为10~(-2),体外保毒期为12小时至两天,病毒粒体为线状。     

广西一点红真菌性病害病原鉴定续报

在已报道的一点红真菌性病害病原菌鉴定的基础上,对最新研究和鉴定的真菌性病害病原菌鉴定进行续报,它们分别是枝枯病、菌核病和炭疽病。枝枯病的病原为洋扁豆大褐斑病菌[Diaporthe phaseolorum(Cke.et Ell.)Sacc.],菌核病的病原为核盘菌[Sclerotinia sclerotiorum(Lib.)de Bary],炭疽病的病原为围小丛壳菌(Glomerella cingulata),其无性态为胶孢炭疽菌(Colletotrichum gloeosporioides)。     

辽宁梨树枝枯病病原菌Diplodia seriata的分离与鉴定

在辽宁兴城秋子梨栽培园出现一种新型枝干病害,主要症状为枝枯及木质部坏死。为明确梨树枝枯病病原菌的分类地位,本研究从辽宁兴城地区采样,经过菌株分离培养和致病性测定,以及形态学鉴定结合病原菌的ITS、EF-1α和β-tubulin多基因联合构建系统发育树,确定引起秋子梨枝枯病的病原菌为色二孢Diplodia seriata。研究结果为明确色二孢引起的辽宁梨树枝枯病发生规律和防治措施的制定提供了理论基础。     

砧木与西瓜品种对黄瓜绿斑驳花叶病毒病的耐病性比较

在上茬棚栽嫁接西瓜上黄瓜绿斑驳花叶病毒病严重发生的田块,应用DAS-ELISA检测法检测播种的10个砧木和西瓜品种对该病毒病的耐病性,发现品种间耐病性差异较大,且西瓜品种耐病性强于砧木品种。5个西瓜品种的病株率为5.0%(小兰)~50.0%(宁波美都),5个砧木品种的病株率为63.6%(强力南瓜)~100%(抗枯先锋1号)。     

大豆花叶病毒的株系鉴定

作者用江苏省大豆重花叶(S_A)、轻花叶(S_B)、黄斑坏死(S_C)、顶枯(S_E)以及黑龙江的黄斑花叶(S_D)和顶枯(S_F)的分离物,在菜豆品种“Top Crop”的离体叶鉴定都产生局部枯斑。6个分离物都可以由几种蚜虫(桃蚜、萝卜蚜、苜蓿蚜)传毒,温度钝化点在50～55℃或55～60℃之间,稀释限点为10~(-2)或10~(-3),体外存活期(室温在25℃以上)为24～36小时,电镜下粒体形态都是线条形,它们的寄主范围都很窄,只侵染豆科植物中的少数几个种。这6个分离物都属于大豆花叶病毒。但是它们的寄主范围和在大豆品种上的反应有所不同、S_A和S_B对扁豆的侵染力很强,S_D和S_F不侵染扁豆,S_C和S_E侵染力居中,S_A和S_B在菜豆品种家雀蛋上发生系统花叶,其余四个分离物只在接种叶上出现黄斑和叶脉坏死。温室内测定了37个大豆品种或品系对6个分离物的反应,没有对6个分离物都免疫的品种,6个分离物在1138—2、493—1等9个品种都出现系统花叶,在合丰23、南农133—3、齐黄1号、徐豆1号和科系8号上,6个分离物的反应有稳定的明显的差异。根据6个分离物在大豆品种、扁豆和菜豆(家雀蛋)上的症状反应,认为6个分离物是大豆花叶病毒的6个不同株系,S_A和S_B的性状相似。室内测定同一个株系在不同品种上反应的症状不同,例如南京重型花叶S_A,轻花叶S_B在许多品种上出现系统花叶但在齐黄1号和徐豆1号上形成系统枯斑。黑龙江的顶枯S_F只在合丰23等少数品种上出现顶枯症状,多数品种是系统花叶。因此,症状类型不能代表株系的特征、而是株系与品种组合之间的特异性反应。我们认为用症状的表现来作为株系的名称是不一定确切的。     

荸荠的一种新病害——荸荠秆枯病

荸荠秆枯病是我省荸荠Eleocharis dulcis)上的一种新的真菌性病害。采用病组织分离纯化的菌种,经多次分生孢子悬浮液喷雾接种进行致病性鉴定,均可表现典型症状。就目前所查阅的文献资料来看,在我国荸荠秆枯病尚未见有记载。根据症状和病原菌形态特征的观察,和1962年Lentz描述的在美国种植的中国荸荠上的荸荠柱盘孢(Cylindrosporium eleocharidis)相似。现将我省荸荠秆枯病发生情况与病原菌简介     

岗梅枝枯病病原鉴定

为明确引起岗梅Ilex asprella枝枯病的病原,对从广东梅州采集的岗梅枝枯病病部分离的致病菌株Gangmei 2进行了形态学观察,并运用MEGA-X构建了病原菌株rDNA内转录间隔区(internal transcribed spacer, ITS)的系统发育树。结果显示:病原菌的形态学特征与拟盘多毛孢属Pestalotiopsis真菌相似,在系统发育树中该菌株与小孢拟盘多毛孢菌Pestalotiopsis microspora在同一分支上。因此,初步将岗梅枝枯病病原菌鉴定为小孢拟盘多毛孢菌P.microspora。     

Possibilities of Biological Control of Liver Flukes

A survey was conducted to gain insight into the perceptions of Lesotho's farmers with regard to insect pests of maize and sorghum, to identify management practices that could impact on stalk-borer numbers and to shed light on other farming practices such as variety selection and crop residue management. Field studies were conducted to determine the incidence and distribution of Busseola fusca (Lepidoptera: Noctuidae) and Chilo partellus (Lepidoptera: Pyralidae) larvae in sorghum and maize residues and to determine the effect of certain crop residue management practices on stalk-borer survival. Results indicated that farmers regard stalk-borers as important pests that sometimes need to be controlled. However, most farmers never apply control measures, mainly due to lack of resources. Residues of maize and sorghum plants are largely used as animal fodder with maize being cut and fed to animals after harvest. Sorghum crop residues are largely left on fields after harvest to be used by free-grazing animals. While stacks of maize stalks were not important in the winter survival of B. fusca larvae, stacking of sorghum ensures winter survival of C. partellus larvae. Detasselling of maize plants is commonly done at plant senescence and the upper halves of plants are fed to animals. Detasselling of maize plants had no effect on the number of borer larvae in plants at harvest.     

Interactions of four pathotypes of Diplocarpon rosae with species and hybrids of Rosa

The interactions of four pathotypes of Diplocarpon rosae with 34 species and hybrids of Rosa were compared in an ongoing search for criteria of potential relevance to rose breeding. There were greater similarities in the resistance‐susceptibility interactions of these roses to the pathotypes DA1, CW1 and ZM1, than to a fourth pathotype, DA2. Among the species roses, only those of the section Cinnamomeae were susceptible to DA2 and this susceptibility was transmitted in several cases to hybrid progeny. CW1 had the greatest pathogenicity of the four pathotypes. In a cross between R. rugosa cv. Scabrosa, which was resistant and R. rugosa f. alba, which was susceptible to all pathotypes, the progeny were tested for resistance to pathotypes DA1, CW1 and ZM1. Each of the 20 progeny was susceptible to all three pathotypes. This shows that, unlike the well characterized Rdr1 gene for resistance to D. rosae, the resistance of R. rugosa cv. Scabrosa is not determined by a dominant major gene. The diploid hybrid, R. rugosa cv. Martin Frobisher × cv. Mistress Quickly, was resistant to all four pathotypes, but an induced tetraploid of this hybrid was susceptible to all pathotypes. The relevance of these findings to the breeding of roses for resistance to black spot disease is discussed.     

桃红颈天牛综合治理技术概述

系统总结国内外有关桃红颈天牛的防治技术,从物理防治、化学防治和生物防治3个方面进行阐述,重点阐述最具生产应用价值的防治技术。最后提出以物理防治为主,生物防治为辅的综合治理措施。即在成虫羽化前用薄膜包扎法阻止天牛成虫产卵,同时设置诱饵树,集中消灭前来产卵的雌虫及其所产的卵,刺杀已孵化的低龄幼虫,8-9月释放管氏肿腿蜂来防治天牛低龄幼虫,在第2年春季注射斯氏线虫或释放花绒寄甲防治天牛幼虫和蛹。上述方法连续进行2年,每年1次,即可将桃红颈天牛的种群数量控制到较低水平。     

吉林省相对资源承载力动态分析

本文采用相对资源承载力的研究思路与计算方法 ,分别以全国、东部沿海经济发达地区和西部欠发达地区作为参照区 ,计算 1 978- 1 998年吉林省相对士地资源承载力、相对经济资源承载力和综合承载力及其变化过程。并指出吉林省经济发展的障碍主要是产业结构和就业结构的配置问题 ,经济发展长期效益不高 ,而且近年来耕地资源减少的问题应该得到重视 ;应加快一二三产业结构及其内部结构的调整 ,转移农村剩余劳动力。要改变经济增长方式 ,合理保护自然资源 ,建立资源节约型国民经济体系     

Registration of mixed formulations of pesticides

Applying pesticides in mixture can bring about an increased level of performance which can be of benefit to manufacturers who make use of this phenomenon when formulating products. The interactions that occur can also bring about adverse effects on performance and possibly on the safety of the product to users, consumers and the environment. Because of this a product containing a mixture of active substances must be considered by registration authorities. Each discipline in the regulatory process must consider the likelihood of an interaction occurring and, as a result, request and examine the necessary data to support approval for that mixed product. Within the European Community the requirements are laid down in Directives that have been introduced to harmonise the regulatory process across Member States. The requirements of these Directives are described as an example of the regulatory process. © Crown copyright 1999. Reproduced with the permission of the Controller of Her Majesty's Stationery Office     

Patterns of interaction between isolates of three pathovars of Pseudomonas syringae and accessions of a range of host and nonhost legume species

Isolates of three pathovars of Pseudomonas syringae were tested against 10 legume species. Some isolates of all pathovars showed cultivar-specific interactions with at least one legume species outside the expected host range. Lablab purpureus and Phaseolus lunatus were found to be hosts to isolates of both P. syringae pv. glycinea and P. syringae pv. phaseolicola, while Lathyrus latifolius was host to isolates of P. syringae pv. pisi and P. syringae pv. glycinea . Lens culinaris showed patterns of interaction with isolates of all three pathovars. Gene models based on mathematical estimates of minimum gene numbers agreed with those previously published for the interactions of P. syringae pv. pisi with Pisum sativum and P. syringae pv. phaseolicola with Phaseolus vulgaris. Two different gene-for-gene models based on five resistance/avirulence gene pairs were proposed to explain observed interactions between Glycine max and P. syringae pv . glycinea . Pathogen isolates which contained no known avirulences defined on their respective host species were found to carry cryptic avirulences recognized by other plant species. Estimates of minimum gene numbers required to explain the interactions of a plant species with all pathogen isolates or to explain the interactions of the isolates of one pathovar with all plant accessions were consistently lower than the sum of the minimum gene numbers required to explain the interactions of each individual component.     

济南地区棉蚜对15种杀虫剂的抗性比较

以室内饲养的相对敏感品系为对照，利用叶片浸渍法制定了济南地区棉蚜对15种杀虫剂的抗性倍数。结果表明：济南地区棉蚜对4种拟除虫菊酯类杀虫剂已达到了较高水平的抗性，抗性倍数在82．21－201．51之间；同时对除丙溴以外的5种有机磷酸酯类杀虫剂亦产生了明显抗性，抗性倍数在7．52－16．38之间，对灭多威、吡虫啉及丙溴磷的抗性尚不明显，但已表现出抗性趋势；对丁硫克百威、硫丹及阿维菌素仍处于敏感水平。     

新疆地衣植物研究历史回顾

本文根据作者１９８５年以来在新疆地衣的研究工作，特别是１９９１年申请到国家自然科学基金课题以后所作的研究工作的基础上，比较前人所做的工作而写出的回顾型论文。标本采集点共计４０个，包括阿尔泰山、天山、昆仑山等山脉，共采集六千多号标本，经过处理鉴定初步定名地衣植物有２６９种，２６５种隶属于８目，３０科，８５属，另半知菌类４属，４种。新疆地区已定名地衣种，主要系泛北极植物区系成分，包括欧、亚森林植物亚区     

柿树炭疽菌侵染柿树叶柄的超微结构观察

 利用透射电镜技术研究了柿树炭疽菌侵染柿树叶柄的超微结构。结果表明:病原菌侵入寄主细胞后,产生细胞内的初生菌丝,其表面沉积凹凸不平的电子不透明物质。一层界面基质(interfacial matrix)把表初生菌丝细胞壁和凹陷的寄主原生质膜分开。随着初生菌丝定殖下一个细胞,原先细胞中的细胞膜消失,形成许多泡囊,随后叶绿体消失,内质网和高尔基体也逐渐降解,最后细胞内物质全部被降解成电子不透明的颗粒,降解的物质沿着初生菌丝和细胞壁表面沉积。初生菌丝穿透细胞壁的过程中,菌丝顶端接触细胞壁后膨大,并在中部产生一个隔膜,然后顶端细胞产生一个较细的穿透菌丝,穿透寄主细胞壁。穿透菌丝在寄主细胞壁中的狭窄处产生一个隔膜,一旦穿透寄主细胞壁后,迅速膨大。次生菌丝在细胞间和细胞内扩展,通过菌丝体对细胞壁施加的机械压力引起寄主细胞壁破裂,或同初生菌丝一起使细胞壁解体。侵染90 h后,形成垫形分生孢子盘。在分生孢子盘周围的表皮细胞中,次生菌丝不断形成子座组织,使原来的子座扩大,子座不断分化形成产梗细胞,产梗细胞产生分生孢子梗,分生孢子梗生长和发育对角质层和表皮细胞壁组织折叠处施加机械压力,使角质层和表皮细胞壁组织进一步折叠,分生孢子盘也相应扩大。     

Enhancement of freshwater production of the seawater greenhouse condenser

Seawater greenhouse(SWGH)is a technology established to overcome issues related to open field cultivation in arid areas,such as the high ambient temperature and the shortage of freshwater.It adopts the humidification-dehumidification concept where evaporated moisture from a saline water source is condensed to produce freshwater within the greenhouse body.Various condenser designs are adopted to increase freshwater production in order to meet the irrigation demand.The aim of this study was to experimentally investigate the practicality of using the packed-type direct contact condenser in the SWGH to produce more freshwater at low costs,simple design and high efficiency,and to explore the impact of the manipulating six operational variables(inlet air temperature of the humidifier,air mass flowrate of the humidifier,inlet water temperature of the humidifier,water mass flowrate of the humidifier,inlet water temperature of the dehumidifier and water mass flowrate of the dehumidifier)on freshwater condensation rate.For this purpose,a direct contact condenser was designed and manufactured.Sixty-four full factorial experiments were conducted to study the effect of the six operational variables.Each variable was operated at two levels(high and low flowrate),and each experiment lasted for 10 min and followed by a 30-min waiting time.Results showed that freshwater production varied between 0.257 and 2.590 L for every 10 min.When using Minitab statistical software to investigate the significant variables that contributed to the maximum freshwater production,it was found that the inlet air temperature of the humidifier had the greatest influence,followed by the inlet water temperature of the humidifier;the former had a negative impact while the latter had a positive impact on freshwater production.The response optimizer tool revealed that the optimal combination of variables contributed to maximize freshwater production when all variables were in the high mode and the inlet air temperature of the humidifier was in the low mode.The comparison between the old plastic condenser and the new proposed direct contact condenser showed that the latter can produce 75.9 times more freshwater at the same condenser volume.