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1.
为明确草地贪夜蛾[Spodoptera frugiperda (J.E.Smith)]寄主生物型,对该虫进行精准监测及防控,采用分子标记方法,对采集于13省(市)29市(区)的83个草地贪夜蛾样本分别进行了COⅠ和Tpi基因片段的扩增和序列比对,以鉴定其寄主种群分化。COⅠ基因序列比对结果显示,草地贪夜蛾水稻型占82%,玉米型占18%;Tpi基因的e4_(183)位点仅北京顺义的1个样本为玉米水稻杂合型,其余均为玉米型。结果表明,草地贪夜蛾是杂合群体,虫源为非单一性。目前以玉米型为主,但有进行水稻型分化的风险,可能对水稻生产造成威胁。  相似文献   

2.
入侵安徽省草地贪夜蛾的遗传分析   总被引:1,自引:0,他引:1  
2019年5月17日在安徽省黄山市黄山区发现草地贪夜蛾为害春玉米,首次证实草地贪夜蛾入侵安徽。本研究采集安徽省7市13县(区)草地贪夜蛾样本共167份,利用线粒体细胞色素C氧化酶亚基Ⅰ基因(cytochrome c oxidase subunitⅠ,COⅠ),以及位于Z染色体上的磷酸甘油醛异构酶基因(triose-phosphate isomerase,Tpi)两个分子标记对样品的群体遗传特征进行分析。基于线粒体COⅠ基因分析结果显示,安徽省草地贪夜蛾样本中86.23%是水稻型,13.77%是玉米型,而且安徽地区样品COⅠ序列特征与美国佛罗里达州种群高度一致。针对水稻型和玉米型的Tpi基因序列10个差异单倍型位点进行分析,发现安徽草地贪夜蛾样品Tpi基因的第3和4位差异单倍型位点有3种不同类型。其中118个样本为玉米型(AT),20个样本为水稻型(GA),29个样本为杂合型(AT/GA),但根据差异单倍型位点的数量判断,所有样品仍属于玉米型。草地贪夜蛾在原产地的多种寄主,如玉米、水稻、大豆、棉花等,在安徽省均有种植,该虫对安徽省粮食生产构成巨大安全隐患。  相似文献   

3.
海南是草地贪夜蛾北迁虫源的重要越冬基地。为监测分析其入侵海南的种群生物型,采用COⅠ和Tpi两种分子标记及碳稳定同位素测定方法,对2020—2022年三亚、海口、儋州高空测报灯诱集的草地贪夜蛾样品进行生物型分析。结果表明,基于COⅠ基因序列比对草地贪夜蛾水稻型占52.08%,玉米型占47.92%;基于Tpi基因第四外显子g Tpi183Y位点鉴定均为玉米型,且g Tpi192Y和g Tpi198Y位点将玉米型分为了3个亚型:Tpi-Ca1 (占比47.73%)、Tpi-Ca2(占比11.36%)、Tpi-Ca1/Ca2(占比40.91%);碳稳定同位素结果显示2020—2022年草地贪夜蛾取食C4(玉米)植物比例分别为42.86%、57.89%、58.34%,同时取食C3(水稻)、C4植物比例分别为57.14%、42.11%、33.33%,而取食C3植物只有2022年8.33%的样本。本研究有助于跟踪监测草地贪夜蛾在海南的生物型情况,为精准监测和早期预警提供参考。  相似文献   

4.
2019年5月31日在陕西省汉中市洋县和镇巴县玉米地首次发现草地贪夜蛾Spodoptera frugiperda (J.E.Smith)幼虫, 到7月8日, 该虫已蔓延至全市所有的11个县区?调查结果显示, 2019年草地贪夜蛾在全市11个县区99个镇393个村发生, 累计发生面积1 004.93 hm2, 平均百株虫量11.01头, 最高百株虫量46头, 平均被害株率10.3%, 最高被害株率80%?通过在全市调查, 只发现草地贪夜蛾幼虫为害玉米, 主要为害玉米心叶幼嫩组织, 在玉米处于大喇叭口期以后生长阶段, 以大龄幼虫为主, 玉米抽雄后幼虫很少, 为害较轻?  相似文献   

5.
大麦田草地贪夜蛾的发生为害及抽样技术   总被引:2,自引:0,他引:2  
草地贪夜蛾在中国可取食为害玉米、高粱、小麦等禾本科作物,但其在大麦田的发生为害情况尚不清楚。我们对云南省曲靖市马龙区处于苗期至分蘖期大麦田的调查结果表明,草地贪夜蛾的虫田率高达62.5%、大麦受害株率为9.33%~100%、虫口密度为1~46头/m2,其中1~3龄幼虫比例达98.6%,受害株率与虫口密度呈显著正相关。大多数草地贪夜蛾幼虫藏匿于大麦心叶为害,取食后叶片形成半透明薄膜窗孔,幼虫在大麦田呈聚集分布。基于空间分布型的研究结果,我们提出了大麦田草地贪夜蛾幼虫理论抽样模型。本研究表明草地贪夜蛾可对大麦生产构成严重威胁。研发的幼虫抽样方法为大麦田草地贪夜蛾幼虫种群调查提供了技术支撑。  相似文献   

6.
为确定我国草地贪夜蛾 Spodoptera frugiperda重点防范区——黄淮海夏玉米区该虫为害籽粒玉米的防治阈值,于2020—2021年分别在籽粒玉米小喇叭口期(6~8叶)、大喇叭口期(8~10叶)和抽雄吐丝期 (12~14叶),通过人工接草地贪夜蛾2龄幼虫进行田间试验,分析不同虫口密度和为害株率下玉米的产量损失,并确定相应防治阈值。结果显示,草地贪夜蛾2龄幼虫密度为2~12头/株时,小喇叭口期、大喇叭口期和抽雄吐丝期的玉米产量损失率分别为16.78%~31.91%、 10.45%~25.14%和15.71%~29.17%,在3个玉米生育期对草地贪夜蛾的防治阈值分别为2龄幼虫55~67头/百株、 97~118头/百株和59~71头/百株;当草地贪夜蛾2龄幼虫为害株率为5%~60%时,小喇叭口期、大喇叭口期和抽雄吐丝期的玉米产量损失率分别为8.81%~22.43%、 4.83%~17.75%和8.16%~20.43%,在3个玉米生育期对草地贪夜蛾的防治阈值为害株率分别为4.24%~5.22%、 7.61%~9.49%和4.46%~5.55%。表明黄淮海夏玉米区草地贪夜蛾在不同生育期为害籽粒玉米的产量损失和防治阈值不同。  相似文献   

7.
甘蓝夜蛾核型多角体病毒Mamestra brassicae multiple nucleopolyhedrovirus(MbMNPV)是一种广谱昆虫病毒,近年来已被应用于草地贪夜蛾Spodoptera frugiperda J.E.Smith的防治上,而不同地区的草地贪夜蛾因环境因子的差异导致其对MbMNPV等生物农药的敏感性不同。本研究首先基于COI和Tpi基因对湖南长沙、河南济源、四川成都、广西南宁和辽宁丹东等5个地区的草地贪夜蛾群体进行了生物型鉴定,同时通过饲毒法测定了不同群体草地贪夜蛾幼虫对MbMNPV的敏感性。结果表明,基于COI基因的鉴定结果显示湖南长沙、河南济源和辽宁丹东的草地贪夜蛾均为水稻型,四川成都和广西南宁群体的草地贪夜蛾为水稻型和玉米型的混合群体,而基于Tpi基因的鉴定结果显示5个群体的草地贪夜蛾均为玉米型。5个群体的草地贪夜蛾3龄幼虫在浓度为1×108 PIB/mL和1×107 PIB/mL的MbMNPV处理下7 d校正死亡率均在90%以上,而浓度为1×106 PIB/mL时,湖南长沙、广西南宁和...  相似文献   

8.
玉米是草地贪夜蛾最嗜好的寄主,然而草地贪夜蛾对玉米生长后期的为害程度和在玉米植株上的分布位置及虫龄结构未见报道.本文采用五点取样法,调查了广西横县甜玉米抽雄期草地贪夜蛾的分布及为害情况.结果表明,玉米生长后期被害株率达(90.60±3.57)%,有虫株率为(51.00±4.97)%,幼虫虫口密度为(68.80±8.85...  相似文献   

9.
小麦田草地贪夜蛾的发生为害、空间分布与抽样技术   总被引:4,自引:0,他引:4  
草地贪夜蛾Spodoptera frugiperda(J.E.Smith)是中国重要的外来入侵害虫,我们调查了该虫在云南省寻甸县麦田的发生与为害。结果表明:田间小麦受害株率为30%~100%,幼虫平均密度4.8~105.6头/m 2,二者呈显著正相关关系。苗期至分蘖期为害小麦的草地贪夜蛾多为低龄幼虫(1~3龄幼虫比例为98.3%),拔节期低龄及高龄幼虫均有,抽穗至灌浆期为害小麦则以高龄幼虫为主(3龄以上幼虫比例达75.4%)。空间分布型分析表明,麦田草地贪夜蛾低龄幼虫呈聚集分布,高龄幼虫为均匀分布。进一步研究提出了基于幼虫密度及龄期的麦田草地贪夜蛾理论抽样模型和基于防治指标的序贯抽样技术。本研究明确了小麦田草地贪夜蛾发生为害的特点、空间分布特征和抽样方法,为田间种群密度调查和幼虫防治工作提供了技术支撑。  相似文献   

10.
为了探究草地贪夜蛾对小麦的为害风险,我们以取食玉米作为对照,开展研究取食小麦对草地贪夜蛾的存活率、取食选择性、生长量和3种解毒酶及乙酰胆碱酯酶的影响。结果表明:草地贪夜蛾初孵幼虫在小麦上的存活率与玉米并无显著差异,高达90%以上。用小麦连续饲喂3龄幼虫7 d,日均体重增加迅速,与取食玉米无显著差异(P0.05)。2龄幼虫取食选择率为小麦玉米,3龄和4龄幼虫的取食选择率为玉米小麦,但均无显著差异。值得注意的是,小麦饲喂48 h后草地贪夜蛾谷胱甘肽S-转移酶活性和多功能氧化酶含量表现为显著诱导上升,而羧酸酯酶和乙酰胆碱酯酶的活性无显著变化。本试验结果初步表明草地贪夜蛾存在为害小麦的风险,应加强草地贪夜蛾在麦田发生情况的监测,同时应重视草地贪夜蛾取食不同寄主对药剂敏感性机制的研究。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
Plant Viruses Transmitted by Whiteflies   总被引:18,自引:0,他引:18  
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.  相似文献   

15.
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.  相似文献   

16.
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 PVYN strain and six to the PVYO strain. No PVYC was found. Two other isolates reacted serologically like PVYO, but were unable to elicit a hypersensitive response from the Nytbr gene and probably represent the PVYZ group. At the molecular level, these two isolates showed a combination of both PVYO and PVYN and could be recombinants of these strains. Another isolate reacted serologically like PVYO, but induced vein necrosis in tobacco, like PVYN-Wilga. Some PVYN isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVYNTN group. The PVYNTN, PVYN-Wilga and PVYZ groups probably represent pathotypes within strains PVYN and PVYO, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.  相似文献   

17.
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.  相似文献   

18.
Molecular diagnostic techniques have been developed to differentiate the Ascochyta pathogens that infect cool season food and feed legumes, as well as to improve the sensitivity of detecting latent infection in plant tissues. A seed sampling technique was developed to detect a 1% level of infection by Ascochyta rabiei in commercial chickpea seed. The Ascochyta pathogens were shown to be genetically diverse in countries where the pathogen and host have coexisted for a long time. However, where the pathogen was recently introduced, such as A. rabiei to Australia, the level of diversity remained relatively low, even as the pathogen spread to all chickpea-growing areas. Pathogenic variability of A. rabiei and Ascochyta pinodes pathogens in chickpea and field pea respectively, appears to be quantitative, where measures of disease severity were based on aggressiveness (quantitative level of infection) rather than on true qualitative virulence. In contrast, qualitative differences in pathogenicity in lentil and faba bean genotypes indicated the existence of pathotypes of Ascochyta lentis and Ascochyta fabae. Therefore, reports of pathotype discrimination based on quantitative differences in pathogenicity in a set of specific genotypes is questionable for several of the ascochyta-legume pathosystems such as A. rabiei and A. pinodes. This is not surprising since host resistance to these pathogens has been reported to be mainly quantitative, making it difficult for the pathogen to overcome specific resistance genes and form pathotypes. For robust pathogenicity assessment, there needs to be consistency in selection of differential host genotypes, screening conditions and disease evaluation techniques for each of the Ascochyta sp. in legume-growing countries throughout the world. Nevertheless, knowledge of pathotype diversity and aggressiveness within populations is important in the selection of resistant genotypes.  相似文献   

19.
In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.  相似文献   

20.
Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.  相似文献   

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