叶绿素荧光成像技术监测苗期小麦白粉病初探

为探究叶绿素荧光成像技术在小麦白粉病监测应用中的可行性, 本研究对接种6个不同浓度小麦白粉菌分生孢子的小麦幼苗离体叶段?一叶一心期幼苗和二叶一心期幼苗以及接种后不同时期进行叶绿素荧光成像测定, 并对导出的叶绿素荧光参数与病情严重度的关系进行分析?结果发现, 接种不同浓度白粉菌分生孢子的小麦离体叶段或幼苗的Fv/Fm图像可以在一定程度上反映出小麦白粉病菌的侵染程度?接种小麦白粉菌后第3天, Fv/Fm值随接种浓度的变化规律不明显, 但从接种后第5天开始, Fv/Fm值随接种浓度的增加而下降, 且未接种的小麦幼苗或离体叶段的Fv/Fm值显著高于接种处理, 接种浓度最高(5 mg/mL)的处理其Fv/Fm值显著低于同时期其他接菌处理?小麦白粉病严重度与叶绿素荧光参数之间的相关性分析表明, Fv/Fm和Chlidx与病害严重度均极显著负相关, 在此基础上, 分别建立了小麦离体叶段?一叶一心幼苗及二叶一心幼苗的基于参数Fv/Fm或Chlidx的病害严重度估计模型?对模型的拟合效果进行比较发现, 基于Fv/Fm或Chlidx的病害估计模型其RMSE或R2比较接近, 因此叶绿素荧光参数Fv/Fm或Chlidx用来估计苗期小麦白粉病发生程度是可行的?本研究为叶绿素荧光成像技术在小麦白粉病监测预警中的应用奠定了理论基础, 具有一定的应用前景?     

豌豆离体叶片鉴定白粉病抗性方法

1997～2001年对豌豆离体叶片鉴定白粉病抗性方法进行了研究。结果表明,将豌豆苗期离体叶片在垫有两层湿滤纸的培养皿内培养,并人工接种白粉病菌,能鉴定出豌豆品种抗白粉病的差异。鉴定结果与田间成株期的抗病性表现基本一致。温度、光照强度、叶龄、病菌接种量等因素影响离体叶片白粉病发生速度或保绿时间。离体鉴定较适宜在温度18～20℃、光照强度3600lx以上、每天12h光照与12h黑暗交替的条件下进行。最适叶龄为二叶一心期或三叶一心期的初展叶。较适宜的接种量为每1cm~2叶面积接种5.5×10~3个分生孢子。     

不同硅源制剂对小麦白粉病的作用效果及对白粉病菌孢子萌发的影响

 研究了不同形态硅源制剂二氧化硅纳米粒子溶胶(60nm和100nm)、正硅酸乙酯、硅酸钠对小麦白粉病的作用效果以及对白粉病菌孢子萌发的影响。结果表明,在相同浓度下几种硅源制剂处理盆栽小麦幼苗对白粉病防效分别为48.78%、43.73%、40.31%和33.29%,室内处理小麦离体叶段对白粉病抑制率分别为59.67%、53.51%、51.10%和42.22%。离体叶段接种白粉菌后1.5~2h、6~7h取样,在相差显微镜下观察白粉菌孢子萌发过程,发现这几种硅制剂对白粉菌孢子初生芽管(PGT)的形成几乎没有影响,但对附着胞(AM)的形成有较大影响,其中以二氧化硅纳米粒子溶胶对AM的影响最大。     

小麦离体叶段鉴定白粉病抗性方法的研究

１９９０年４月至１９９４年４月对小麦离体叶段鉴定白粉病抗性方法进行了研究。结果表明：（１）在灭菌条件下，以在培养皿中垫两层滤纸，用６ＢＡ作保绿主，超过人主至进行鉴定效果较好。（２）保绿剂的浓度低，发病快、退绿早，反之反病慢、退绿晚。其最适浓度是：苗期６ＢＡ为６０－１００ｐｐｍ、苯咪唑为６０ｐｐｍ ；成株期６ＢＡ以８０－１５０ｐｐｍ为佳。（３）份病快、退绿迟的角度出发，鉴定材料以株龄小、叶龄短的初展     

2008年我国主要麦区白粉菌群体对三唑酮和喹氧灵的敏感性监测

采用拌种离体叶段法对我国6个省(市)分离的小麦白粉菌108个和104个单孢堆菌株分别对三唑酮和喹氧灵的敏感性进行了测定,并对两者之间的交互抗性进行分析。结果表明,供试菌株对三唑酮的平均EC50为94.34mg/L,平均抗性水平达45.14倍,有97.25%菌株产生了抗性,其中高抗菌株(抗性水平40)占35.19%,中抗菌株占55.56%。河北菌株的抗性水平明显高于其他五省。小麦白粉病菌群体对喹氧灵的敏感基线为0.0059mg/L,且与三唑酮无交互抗性。此研究信息可为小麦白粉病抗药性持续治理措施的制定以及杀菌剂生产和使用策略提供依据。     

不同小麦品种对苯磺隆耐药性差异及其机理

室内用砂培法测定11种小麦品种对苯磺隆的相对敏感性,其敏感性有较大差异.碧玛4号、维麦8号对苯磺隆有很强的耐药性,IC50可分别达到502.6和409.3aiμg/kg,济1 3号为156.9aiμg/kg,鲁麦22号、黄县大粒对苯磺隆较为敏感,IC50低于45.0 aiμg/kg.以上5种小麦离体ALS对苯磺隆的敏感性没有明显差异,敏感品种黄县大粒IC50为154.2nmol/L,甚至较维麦8号149.3nmol/L略高.ALS活体试验表明,小麦可以很快恢复苯磺隆对ALS活性的抑制,且耐药型品种恢复能力较强,碧玛4号、维麦8号ALS恢复活性只需1.5天,敏感品种需3天.碧玛4号、维麦8号除草剂解毒酶系GSTs相对于敏感品种对苯磺隆有较大的反应幅度和较短的反应时间,第2天就分别达到1.46、1.42的峰值,而济13号、鲁麦22号、黄县大粒变化幅度较小,第3天才达到峰值,活性分别为1.39、1.33和1.32.研究表明,小麦各品种对苯磺隆的耐药能力产生差异的主要原因之一是小麦GSTs对苯磺隆的代谢所致,而与小麦ALS对苯磺隆的敏感程度无关.     

哈茨木霉菌BM6对小麦白粉病的防治研究

研究哈茨木霉菌BM6对小麦白粉病菌的拮抗作用和对温室盆栽苗小麦白粉病的防治效果,以及对小麦叶片中活性氧、木质素和丙二醛含量的影响。结果表明,哈茨木霉菌BM6发酵液对小麦白粉菌孢子萌发有明显的抑制作用,抑制率为84.26%,对小麦白粉病的防效可达51.59%。在哈茨木霉菌BM6发酵液处理小麦叶片后,提高了活性氧活性、木质素和丙二醛的含量,分别在第1天、5天和第3天出现高峰值。说明哈茨木霉菌BM6发酵液诱导引起小麦叶片活性氧迸发、木质素和丙二醛含量的升高,进而增强了小麦的抗病性。     

太子参叶斑病抗性诱导因子筛选

为筛选诱导太子参产生对叶斑病抗性的诱导因子,在离体培养条件下,用水杨酸、草酸、壳聚糖、磷酸氢二钾、亚硒酸钠和太子参叶斑病粗毒素液这6种因子诱导处理太子参组培苗,在1～7d内测定叶片相关酶活性的变化。诱导培养7d后,用太子参叶斑病粗毒素液对组培苗进行离体叶片针刺接种抗性鉴定,结果表明,诱导处理后能明显增强太子参叶片内POD、PPO和PAL的活性;6种因子均能诱导太子参对叶斑病产生抗性,以190mg.L-1和380mg.L-1草酸的诱抗效果较好,分别达到76.1%和74.7%,极显著高于其它诱导因子的诱抗效果。     

两种候选甲氧基丙烯酸酯类杀菌剂对黄瓜霜霉病的作用方式

20%唑胺菌酯EC、20%SYP-3998 SC是甲氧基丙烯酸酯类候选杀菌剂,为探索两药剂对黄瓜霜霉病的作用方式,采用盆栽植株喷雾-叶碟法、叶碟喷雾法、盆栽植株喷雾-叶碟法分别测定两药剂对黄瓜霜霉病的保护、治疗及持效期,并采用离体叶片法、叶碟法测定二者对黄瓜霜霉病的铲除作用.结果表明:20%唑胺菌酯EC和20%SYP-3998 SC具有良好的保护、治疗及铲除作用.两药剂的铲除作用表现在能抑制黄瓜霜霉病菌病斑扩展、孢子囊产生及孢子囊再侵染,与孢子囊混合接种能显著降低孢子囊的致病性.此外,20%唑胺茵酯EC和20%SYP-3998 SC具有7～10天的持效期;20%唑胺茵酯EC预防、治疗、铲除效果及持效性均优于20%SYP-3998 SC及对照药剂25%嘧菌酯SC.     

三个小麦新品系抗白粉病基因分析

 用4个具有不同毒力的小麦白粉菌生理小种,分别接种5个小麦品种(系)半双列杂交的F₁、F₂和BC₁F₁群体的幼苗离体叶段,初步鉴定出野二燕3号具有1对抗1号和11号小种的显性抗病基因;JYP-2具有2对独立的显性抗病基因,其中1对基因抗1、11和311号小种,另1对基因只抗1和11号小种;贵农21号具有2对显性抗病基因,其中1对抗311和313号小种,另1对只抗1和11号小种,这对基因与JYP-2具有的抗1和11号小种的基因是相同的。3个小麦新品系共鉴定出4对不同的抗病基因。本文还讨论了采用幼苗离体叶段接种,同一批单株接种2个以上小种,定单株编号,记载和统计的方法,在抗白粉病基因分析中的作用。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.