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1.
针对我国柑橘园柑橘全爪螨种群严重发生的现状,本文应用均匀设计,通过干扰作用控制指数评价了印楝素的不同施用浓度和使用次数对柑橘园柑橘全爪螨自然种群控制作用,并建立了控制效果随这些因素变化的回归模型。结果表明,印楝素的使用次数对柑橘全爪螨种群的影响程度强于施用浓度,印楝素单独使用一次不能有效控制柑橘全爪螨种群的数量增长趋势,印楝素3.75 mg/L浓度使用2次或2.50、3.00 mg/L浓度使用3次,可使柑橘全爪螨种群数量得到较为有效的控制。  相似文献   

2.
31种中草药提取物对柑橘全爪螨的杀螨活性   总被引:2,自引:0,他引:2  
室内测定了31种植物的乙醇提取物对柑橘全爪螨的杀螨活性。结果表明:小茴香等4种植物的活性较高,24 h校正死亡率大于90%;藁本等7种植物的活性中等,校正死亡率为60%~90%;其余植物提取物的校正死亡率在60%以下。进一步测定了4种植物提取物对柑橘全爪螨的雌成螨和卵的触杀毒力,表明:小茴香对柑橘全爪螨的毒力最高,LC50值分别为0.065 8 g/L和144.180 5 g/L,可以作为下一步的研究对象。  相似文献   

3.
柴油及其与阿维菌素复配对柑橘全爪螨卵的作用   总被引:1,自引:0,他引:1  
室内测定了柴油对柑橘全爪螨卵的毒力及其与阿维菌素复配植物油基新型乳油的杀卵作用。结果表明,柴油对柑橘全爪螨卵的LC50为2790.39μg/mL;两种柴油与阿维菌素复配新型乳油1000、750和500倍液3种浓度下的杀卵率均高于90%,其中添加了印楝油的复配剂3浓度的杀卵率与对照药剂24%螺虫乙酯SC 3000倍液相当。  相似文献   

4.
为筛选新型绿色植物源杀螨剂,采用水蒸气蒸馏法提取7种植物精油,通过Potter喷雾法、熏蒸法、药膜法测定精油对苹果全爪螨Panonychus ulmi (Koch)的触杀、熏蒸、驱避活性,筛选出生物活性较强的薄荷精油,并通过气相色谱-质谱联用仪技术(GC-MS)对薄荷精油进行了化学成分的鉴定和分析。结果表明:薄荷精油喷雾触杀12、24、48 h后的LC50分别为2.13、0.83、0.77 g/L,熏蒸12、24、48 h后的LC50分别为382.86、73.89、16.08μL/L,说明薄荷精油对苹果全爪螨具有较强的触杀和熏蒸活性。最后,驱避处理24h后,薄荷精油对苹果全爪螨的驱避活性较强,驱避率为77.82%,驱避等级为Ⅳ级。薄荷精油经GC-MS分析,共鉴定出34种化学成分,所检测出的化学成分占精油总含量的99.67%,其主要成分为薄荷醇(32.16%)、D-柠檬烯(16.44%)、4-异丙基甲苯(11.32%)、3-蒈烯(10.27%)、丙二酸二乙酯(9.57%)、薄荷酮(3.91%)。由此可见,薄荷精油对苹果全爪螨有较强的生物活性,为...  相似文献   

5.
为明确植物源活性化合物滨蒿内酯的杀螨活性及作用方式,测定了滨蒿内酯对植食性害螨朱砂叶螨(Tetranychus cinnabarinus)的幼螨、若螨、雌成螨的触杀活性;同时测定了其对雌成螨的产卵抑制和驱避活性,以及杀卵活性.结果表明,滨蒿内酯对朱砂叶螨雌成螨具有较高的触杀毒力,48h的LC_(50)为0.157mg/mL;滨蒿内酯对朱砂叶螨不同螨态的触杀活性的从大到小依次为雌成螨、若螨、幼螨,其无明显的杀卵活性;滨蒿内酯对雌成螨表现出较强的驱避作用,同时对雌成螨具有明显的产卵抑制作用,且处理后96h的产卵抑制率达到58.28%.说明滨蒿内酯对朱砂叶螨的主要作用方式为触杀、驱避和产卵抑制作用.  相似文献   

6.
用240g/L螺螨酯SC对柑橘全爪螨进行了防治试验。结果表明:在柑橘全爪螨卵孵化盛期至若螨低龄期施用240g/L螺螨酯SC,药后20d防效最高,可达96.12%,对柑橘全爪螨均有较好的防治效果,且试验药剂对柑橘安全,其防治柑橘全爪螨推荐使用浓度为60mg/kg。  相似文献   

7.
柑橘全爪螨是重要的柑橘害虫之一, 对多种化学农药已产生抗性。为合理选择防治药剂, 更好地防治该害虫, 本研究选择7种药剂采用改进浸叶法对柑橘全爪螨雌成螨进行了室内毒力测定, 并参照农药田间药效试验准则开展了田间药效试验。研究结果表明, 7种药剂对柑橘全爪螨的毒力从大到小依次为乙唑螨腈(0.818 mg/L)、丁氟螨酯(4.645 mg/L)、印楝素(4.878 mg/L)、氟啶胺(16.844 mg/L)、哒螨灵(21.167 mg/L)、乙螨唑(69.834 mg/L)、螺虫乙酯(417.089 mg/L)。乙唑螨腈和丁氟螨酯的速效性好且持效期长, 对柑橘全爪螨的防效显著高于其他供试药剂, 可作为防治的首选药剂。此外, 氟啶胺对柑橘全爪螨也有较高的毒力和防效, 作为一种广谱高效的保护性杀菌剂, 可在防治柑橘病害的同时防治害螨, 病虫兼治。  相似文献   

8.
黄皮种子甲醇提取物对茶黄蓟马的生物活性   总被引:1,自引:0,他引:1  
研究了黄皮种子甲醇提取物对茶黄蓟马(Scirtothrips dorsalis Hood)的驱避和触杀作用。结果表明:黄皮种子甲醇提取物对茶黄蓟马有较强的驱避活性,在浓度为20 g/L时,12 h和24 h对茶黄蓟马的驱避率分别为92.86%和89.91%;另外,提取物对茶黄蓟马有一定的触杀作用,处理后12 h和24 h对茶黄蓟马的致死中浓度(LC50)分别为16.60 g/L和12.85 g/L。各萃取相中石油醚相的活性最高,质量浓度为5 g/L 时,石油醚萃取物对茶黄蓟马24 h 后的校正死亡率为49.37%。  相似文献   

9.
为评价印楝素对柑橘全爪螨的控制效果,进行田间防治试验。结果表明,0.3%印楝素乳油600~800倍液对柑橘全爪螨的防治效果较好,药后1 d和3 d,防治效果与对照药剂10%阿维菌素悬浮剂相当,药后7~14 d防治效果显著高于对照药剂。0.3%印楝素乳油随药后时间延长而药效提高,药后3 d,防治效果在70%以上,有较好的速效性;药后14 d防治效果达80%以上,基本控制了柑橘全爪螨的为害,有较好的持效性。  相似文献   

10.
采用药膜滤纸法测定除虫菊素、烟碱、鱼藤酮、蛇床子素、印楝素、苦参碱6种植物源农药四纹豆象的触杀活性。结果表明,6种供试药剂对四纹豆象的LC50分别为7.0771、7.5804、66.3049、16.1044、25.4777和85.5233μg/cm2;触杀活性测定结果表明,除虫菊素对四纹豆象的触杀活性最强,烟碱次之,其它4种供试药剂对四纹豆象的触杀活性较弱。  相似文献   

11.
In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.  相似文献   

12.
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   

13.
The epidemiology ofSitobion avenae and its natural enemies in winter wheat was studied in 1975, 1976 and 1977. Immigration was important until the end of flowering. The alate immigrants had apterous offspring. These became the driving force in population growth. Their offspring were mostly alatae which usually left the field. A model of the epidemic was developed. Quantitative relations between the aphids and their environment were obtained from literature or established in laboratory trials. The model simulated population development and population composition from the beginning of June till the population peak at the end of June or early in July. Because quantitative data on relations between aphids and their natural enemies and pathogens are scarce, and since the knowledge on wing formation is still limited, the population collapse could not be predicted. In the future, prognosis over a period of three weeks seems possible.Samenvatting De toenemende betekenis van graanbladluizen (vooralSitobion avenae) gepaard gaande met een sterke toename van het gebruik van insecticiden op granen maakte verbetering van de prognose over het schadelijk optreden wenselijk. Door gedetailleerde tellingen in het veld (Fig. 1–7) werden gegevens verkregen over het verloop van de epidemie en het optreden van natuurlijke vijanden in 1975, 1976 en 1977.Een immigratieperiode tot in de bloei kon worden vastgesteld. Daarna lijkt de aantrekkelijkheid van het gewas voor alate luizen te verminderen. De alate immigranten krijgen aptere nakomelingen. Deze vormen de stuwende kracht van de populatiegroei. De nakomelingen van apteren zijn merendeels alaat. Zij verlaten het gewas.Een model van de populatieontwikkeling gedurende de epidemie werd opgesteld. De relatiediagrammen Fig. 9 en 10 laten groei en ontwikkeling vanS. avenae en een predator (Syrphus corollae) zien. Kwantificering van de betrekkingen werd mogelijk door literatuurgegevens en laboratoriumexperimenten.Met het model kon de populatieontwikkeling vanS. avenae vanaf begin juni tot aan de populatiepiek in 1975, 1976 en 1977 vrij goed worden gesimuleerd (Fig. 12). Ook de populatieopbouw kon worden gesimuleerd (Fig. 14). De teruggang van de populatiedichtheid blijkt moeilijker te voorspellen door het ontbreken van gegevens over natuurlijke vijanden.Het lijkt waarschijnlijk dat in de toekomst met het model een prognose over de piek van de bladluispopulatie circa 3 weken tevoren mogelijk zal zijn.  相似文献   

14.
Barley yellow dwarf disease is one of the most important problems confronting cereal production in Iran. Barley yellow dwarf virus-PAV (BYDV-PAV) and Cereal yellow dwarf virus-RPV (CYDV-RPV) are the predominant viruses associated with the disease. One isolate of BYDV-PAV from wheat (PAV-IR) and one isolate of CYDV-RPV from barley (RPV-IR) were selected for molecular characterisations. A genome segment of each isolate was amplified by PCR. The PAV-IR fragment (1264 nt) covered a region containing partial genes for coat protein (CP), read through protein (RTP) and movement protein (MP). PAV-IR showed a high sequence identity to PAV isolates from USA, France and Japan (96–97%). In a phylogenetic analysis it was placed into PAV group I together with PAV isolates from barley and oats. The fragment of RPV-IR (719 nt) contained partial genes for CP, RTP and MP. The sequence information confirmed its identity as CYDV. However, RPV-IR showed 90–91% identity with both RPV and Cereal yellow dwarf virus-RPS (CYDV-RPS). Phylogenetic analyses suggested that it was more closely related to RPS. These data comprise the first attempt to characterise BYD-causing viruses in Iran and southwest Asia. The nucleotide sequence data reported appear in the EMBL, GenBank and DDBJ Nucleotide Sequence Databases under the accession numbers AY450425 and AY450454  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.
During a survey conducted from 1998 to 2002, Fusarium proliferatum was found associated with young and adult palms belonging to the genera Chamaerops, Phoenix, Trachycarpus and Washingtonia showing symptoms of wilt and dieback. The fertility and toxicological profile of 36 strains representing different locations and hosts were studied. All of them except two, which were infertile, belonged to mating population D. Both mating types (MATD-1 and MATD-2) were isolated from the same host species, showing a high potential of genetic recombination in the field. Additionally, eight strains were fertile once crossed as female. Toxin analysis showed differences in the ability of strains to produce fumonisin B1, moniliformin, beauvericin, fusaric acid and fusaproliferin. Only 17 of them produced all the toxins analyzed. Pathogenicity tests were conducted on Phoenix dactylifera and P. canariensis using nine F. proliferatum Spanish strains and two reference strains from Saudi Arabia. Eight months after inoculation all strains caused disease, with palms showing lesions on the bases of leaves and development of wilt symptoms similar to those originally observed in affected plants. This is the first report on the occurrence of F. proliferatum on P. dactylifera in Spain and also the first report of this pathogen on C. humilis, P. canariensis, P. reclinata, T. fortunei, W. filifera and W. robusta.  相似文献   

17.
Corynebacterium fascians, which causes leafy gall, has been shown to be responsible for the unusual symptoms recently found in lilies. The symptoms are described and the different bacterial isolates compared by biochemical, serological and pathogenicity experiments. No evidence could be found for the existence of specialized strains even though considerable variation in virulence could be demonstrated. Although the role of variation in susceptibility of the different lily cultivars should not be underestimated, it would appear that high inoculum levels ofC. fascians in the soil may be largely responsible for these outbreaks.Also included in this study are the results of biochemical, serological and pathogenicity experiments ofC. fascians which has been isolated fromKalanchoe, Euphorbia, Brodiaea, Hebe andVerbascum.Samenvatting Reeds een aantal jaren was in lelies een woekering in stengelbollen bekend, die echter sporadisch voorkwam en economisch van weinig betekenis was. Tijdens de zomer van 1977 echter trad de ziekte op één enkel perceel zo ernstig op dat zeer aanzienlijke oogstderving het gevolg was. Behalve de stengelbol kan ook de hoofdbol misvormd zijn. Bovendien kunnen misvormde stengelbollen lange spruiten vormen, zgn. sabeltandvorming. Soms is het wortelstelsel gereduceerd; in de kas zijn verdikte stengels waargenomen. De ziekte staat nu bekend onder de naam woekerziekte.Door de PD te Wageningen en het LBO te Lisse werd de bacterieCorynebacterium fascians (Tilford) Dows. uit het zieke materiaal geïsoleerd. In gezamenlijk onderzoek werd nagegaan of de bacterie de veroorzaker is van bovengenoemde symptomen en of hier sprake is van een op lelie gespecialiseerde stam.Biochemische en serologische vergelijkingen tussen isolaten vanC. fascians uit lelie,Kalanchoe, Euphorbia, Brodiaeea, Hebe enVerbascum laten zien dat er zeer weinig verschillen bestaan. Alle isolaten reageren op een standaard antiserum met titers variërend tussen 1: 640–1: 5120.Een oriënterende inoculatieproef werd uitgevoerd op het LBO in 1977. Daarna werden op de PD 10 van de 25 isolaten uit lelie en 8 uit andere waardplanten getoetst op lelie, chrysant en lathyrus. Uit de inoculatieproeven blijkt, dat de bacterie de veroorzaker is van de waargenomen symptomen. Tussen de isolaten blijkt een groot verschil in pathogeniteit te bestaan (12–100% aantasting), zonder dat dit aan herkomst gebonden is. Het voorkomen van op lelie of andere waardplanten gespecialiseerde stammen is daarom niet aan te nemen.In hoeverre de hevige aantasting een gevolg is van een opbouw van de bacterie-populatie door een te nauwe vruchtwisseling en mechanische rooimethoden moet worden nagegaan.  相似文献   

18.
Research on root rot pathogens of peas in the Netherlands has confirmed the prevalence ofFusarium solani, F. oxysporum, Pythium spp.,Mycosphaerella pinodes andPhoma medicaginis var.pinodella. Aphanomyces euteiches andThielaviopsis basicola were identified for the first time as pea pathogens in the Netherlands. Other pathogens such asRhizoctonia solani andCylindrocarpon destructans were also found on diseased parts of roots. F. solani existed in different degrees of pathogenicity, and was sometimes highly specific to pea, dwarf bean of field bean, depending on the cropping history of the field.A. euteiches was specific to peas, whereasT. basicola showed some degree of physiological specialization.  相似文献   

19.
Organic amendments and green manure are potential alternatives to the harmful chemical control means currently used against plant-parasitic nematodes. In this work, Chrysanthemum coronarium was applied to the soil as a green manure to control the root-knot nematodes Meloidogyne incognita and M. javanica. Chrysanthemum coronarium significantly reduced nematode infection of tomato roots and improved plant-top fresh weight, both in the greenhouse and in microplots. Other green manures, derived from Anthemis pseudocotula, wild chickpea (Cicer pinnatifidum), Geranium spp. and wheat, were not as effective as C. coronarium. Chrysanthemum coronarium, retained its nematicidal activity even when applied as a dried material. Only mature C. coronarium plants, in their flowering stage, exhibited nematode control activity, but the green plant parts were more effective than the flowers. An aqueous extract of C. coronarium exhibited in vitro, nematostatic activity towards M. incognita and M. javanica second-stage juveniles and inhibited their hatching from eggs and egg-masses; its nematostatic activity was expressed also against other phytonematode species such as Heterodera avenae and Pratylenchus mediterraneus, but did not affect the beneficial entomopathogenic nematode Steinernema feltiae.  相似文献   

20.
浅黄恩蚜小蜂和丽蚜小蜂对温室白粉虱的寄生潜能分析   总被引:1,自引:1,他引:0  
浅黄恩蚜小蜂Encarsia sophia GiraultDodd和丽蚜小蜂Encarsia formosa Gahan是防治粉虱类害虫的优势寄生蜂,通过生命表技术方法分析了2种寄生蜂对温室白粉虱Trialeurodes vaporariorum(Westwood)的防治潜能。结果表明,丽蚜小蜂在羽化第3天和第10天出现2次寄生高峰,占其总寄生量的13.7%和8.0%,在2次高峰之间逐日寄生粉虱数量比较平稳,单雌逐日平均产雌数保持在10.6~13.4头,10 d后寄生量呈明显的下降趋势;而浅黄恩蚜小蜂羽化10 d内逐日寄生粉虱量变化不大,单雌逐日产雌数稳定在4.2~5.4头,羽化14 d后寄生量呈明显下降趋势。丽蚜小蜂和浅黄恩蚜小蜂的R0、T、rm、λ值分别为171.5、18.0、0.2854、1.3303和61.6、16.2、0.2544、1.2897;粉虱若虫充足时,丽蚜小蜂平均单雌寄生若虫数是浅黄恩蚜小蜂的2.7倍,而后者平均单雌取食若虫数为60.6头,明显高于前者42.7头,总的来看,丽蚜小蜂通过寄生和取食杀死粉虱总量220.8头,明显高于浅黄恩蚜小蜂的127.9头。表明在应用寄生蜂防治温室白粉虱时,单独释放丽蚜小蜂比浅黄恩蚜小蜂显示出更好的防治潜能。  相似文献   

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