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1.
Oviposition deterrents have potential to prevent arthropod pest infestations making the crop habitat less or no favorable for pests to lay eggs and even to settle. In this study, seed oils of maize, safflower, rapeseed and castor oil plant were evaluated in the field between years of 2015 and 2016 for their oviposition deterrent activity against winterform females of pear psylla, Cacopsylla pyri (L.) (Hemiptera: Psyllidae), the most important insect pest of pears in Turkey. All the oils were used at three different concentrations, 1, 1.5 and 2 L/100 L water including 0.01% Tween-20 for a good mixture and applied at the dormant period (just before the first eggs were deposited by overwintered females). Only one application was made each year. Oviposition deterrency was evaluated by counts of eggs deposited by overwintered females of the pest on treated dormant shoots during the sampling times 3, 7, 14, 21 and 28 days after application. The results showed that significant reductions in total numbers of eggs laid by winterform females were observed in all the oil-treated plots compared with the controls sprayed with tap water including Tween-20 (0.01%). Safflower and castor oils exhibited 100% oviposition deterrent activity at all the concentrations during the 3 weeks period in both years. Even after 4 weeks, the deterrency of these oils was higher than 70%. In the control plots, the first eggs were deposited by overwintered females within 3 days after application in both years. These findings suggest that these oils are promising oviposition deterrents against winterform females of C. pyri.  相似文献   

2.
A botanical natural product,AkseBio2, was evaluated under laboratory conditions for its oviposition deterrent, ovicidal and larvicidal (nymphicidal) effects against the pear psyllaCacopsylla pyri (L.) (Hemiptera: Psyllidae). The product exhibited a strong oviposition deterrent effect for winterform and summerform females and caused a reduction in the total number of eggs laid in both choice and no-choice assays. Significant mortalities in freshly laid eggs (0–48 h) and various nymphal stages of the pest were recorded in toxicity assays. At a concentration of 0.1% (formulation), the highest biological activity of the product was recorded against the young (1st and 2nd) nymphal stages (up to 87.4% mortality) in comparison with the other biological stages of the pest. It was less active against the older (3rd-5th) nymphs, causing 62.1% mortality at the same concentration. In assays with non-target organisms, a significant negative effect was not observed. There were no significant changes on treated plants up to 7 days after treatment in any trial, nor was there any phytotoxicity on plant tissue as a result ofAkseBio2 treatments. The results suggest that the product can be used in psylla control instead of synthetic insecticides and may serve as an integrated pest management (IPM) component in pear orchards. http://www.phytoparasitica.org posting July 14, 2004.  相似文献   

3.

Oviposition deterrent activity of a natural enemy food supplement, Envirofeast, against Ostrinia nubilalis Hubner females was studied in choice and no-choice tests under laboratory conditions. Maize plants treated with Envirofeast at 25-40 g a.i./l had significantly fewer egg masses per leaf and eggs per egg mass laid on them compared with the untreated control plants in both choice and no-choice tests. However, maize plants treated with Envirofeast concentrations of 10-20 g a.i./l did not significantly deter the insect's oviposition. The optimum rate at which Envirofeast could deter oviposition was 25 g a.i./l. Increasing the rate of Envirofeast application from 25 g to 40 g a.i./l did not significantly increase its oviposition deterrent activity against O. nubilalis. However, reducing the rate from 25 to 20 g a.i./l resulted in a significant reduction in the oviposition deterrent activity of Envirofeast. The egg masses laid by O. nubilalis on Envirofeast treated plants were essentially (80%) located on the lower leaf surfaces in contrast to untreated (control) plants where only 40-60% of the egg masses were deposited on the lower leaf surfaces. The egg masses on the Envirofeast-treated plants were found at sites which did not receive sprays, indicating the importance of good spray coverage when the product is used in the field. The study has demonstrated the oviposition deterrent activity of Envirofeast against O. nubilalis on maize and this indicates that Envirofeast may have the potential to be integrated into programmes to assist in the control of O. nubilalis on maize.  相似文献   

4.
A laboratory study conducted in 2003 determined the influence of a kaolin-based particle film (Surround WP Crop Protectant) on spruce budworm (Choristoneura fumiferana (Clem)) oviposition. Three concentrations (15, 30 and 60 g litre(-1) spray carrier) were applied to white spruce (Picea glauca (Moench) Voss). When presented with different paired choices of oviposition surfaces, spruce budworms laid very few egg masses overall and showed no significant (P < 0.05) preference between kaolin-coated and untreated foliage. During no-choice tests, spruce budworms were significantly (P < 0.05) less inclined to oviposit on the 60 g kaolin litre(-1) treated foliage than on the controls, but no kaolin treatment completely inhibited spruce budworm oviposition. Egg mass size and percentage hatch were unaffected by the kaolin treatments, and overall the percentage of egg masses laid on foliage was inversely proportional to treatment concentration. It is unlikely that kaolin-based particle film would be practical for wide use in natural forests without significant adaptations to current pesticide application equipment and methods. However, the technique might be feasible in selected urban settings.  相似文献   

5.
Studies were conducted to evaluate the effect of a kaolin-based particle film against the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae). The effect of the particle film on development, survival and host plant selection was tested on calabrese seedlings, Brassica oleracea italica Plenck cv. Fiesta F(1), under controlled environmental conditions in the laboratory. Survival to adulthood was significantly reduced and development time increased on kaolin-treated compared with water-treated host plants. The hatch rate of neonate P. xylostella larvae from eggs laid on an artificial substrate was unaffected by the particle film applied after oviposition. Experiments showed that, when given the choice, significantly fewer larvae first made contact with the kaolin-treated compared with the water-treated plant material and that after 24 h there were still significantly fewer larvae present on kaolin-treated leaves. Adult females, however, deposited more eggs on host plants coated with the kaolin particle film. As part of this series of experiments the water control treatment was compared with plant material which had been sprayed with kaolin on the upper surface only and on both leaf surfaces. In general, any observed treatment effect was enhanced with an increase in the particle film coverage. The results warrant the extension of investigations of kaolin-based particle films to field-based P. xylostella management strategies.  相似文献   

6.
F. Erler  H. Cetin 《Phytoparasitica》2005,33(2):169-176
A field trial was carried out to evaluate the efficacy of several selective insecticides for the control of pear psyllaCacopsylla pyri (L.) (Hemiptera: Psyllidae) in two successive years. Three insect growth regulators (IGRs) — diflubenzuron, pyriproxyfen and teflubenzuron, and an amin-hydrazine derivative — amitraz, were evaluated singly and in combination with summer oil (1%). All insecticides were applied at recommended label rates in both years. When compared with the untreated control, all insecticides alone and their combinations with summer oil, except for pyriproxyfen alone, provided control of young (1st and 2nd instars) nymphs. However, combined applications of these insecticides and summer oil were more effective than either insecticide alone for controlling the egg and young nymph stages of the pest. The products were less effective against older (3rd–5th instars) nymphs, even in combination with summer oil, and failed to suppress the population of older nymphs. Adding oil to sprays also delayed oviposition by winterform and summerform females. With the exception of oil with amitraz, combinations of insecticides with summer oil did not cause any phytotoxicity during the study.  相似文献   

7.
Oviposition deterrents have the potential to prevent insect infestations in agroecosystems. In the present study, the level and duration of this behavioral effect was evaluated against pear psylla,Cacopsylla pyri (L.) (Hemiptera: Psyllidae), a serious pest of pears in Turkey. The activity of four oily substances — cotton seed oil, fish-liver oil, neem oil and summer oil — was tested against winterform and summerform females of the pest in laboratory and field experiments, in order to determine their oviposition deterrency and stability as deterrents. In the laboratory assays, the initial (3 days after treatments) deterrency of all test materials was 100%. While decreases in initial deterrency started after 1 week for neem oil and after 2 weeks for cotton seed oil, fish-liver oil and summer oil exhibited 100% deterrent activity against winterforms, but not summerforms during the 3-week test period. The last two also exhibited strong oviposition deterrent activity for both forms ofC. pyri females in field trials. A significant reduction in the total number of eggs laid was observed in the field plots. Data showed that summer oil and fish-liver oil are the most promising oviposition deterrents against pear psylla females. http://www.phytoparasitica.org posting Sept. 28, 2004.  相似文献   

8.
Neem(Azadirachta indica A. Juss.) seed kernel (NSK) extracts,viz., NSK aqueous suspension (NSKS), ethanolic extract of NSK (EtOH. NSK), hexane extract of NSK (neem oil), ethanolic extract of the hexane extract (EtOH. oil) and acetone extract of deoiled NSK powder (Acet. DNSKP) at 1.25-20% concentrations, and pure azadirachtin at 1.25-10 ppm, were evaluated as oviposition deterrents toBactrocera cucurbitae (Coq.) andB. dorsalis Hendel. NSKS at ≥5% under choice test conditions, and at all concentrations (≥1.25%) in no-choice tests significantly deterred oviposition in both species. Similarly, EtOH. NSK was significantly active at all the concentrations tested for both species in choice and no-choice tests. However, with neem oil and EtOH. oil sensitivities of the two species differed considerably. Both extracts deterred oviposition byB. cucurbitae at all the concentrations tested under both choice and no-choice test conditions. On the other hand, withB. dorsalis, neem oil was significantly deterrent only at 20% in both test regimes and at 5% and 20% for EtOH. oil under choice and no-choice test conditions, respectively. Acet. DNSKP significantly deterred oviposition by both species at all concentrations tested. Azadirachtin failed to deter oviposition in either species.  相似文献   

9.
为了比较2个转cry1Ab基因抗虫籼稻品系B1和B6对其非靶标害虫白背飞虱敏感性与其非转基因亲本对照嘉早935的差异,采用历期测定和产卵行为电子记录等方法分别测定了白背飞虱于B1和B6及嘉早935上的发育历期、产卵行为及繁殖力。结果表明,该飞虱以B1和B6为食时,其雌雄若虫总发育历期均显著长于对照,其中在B1上各延长了1.3和1.5天,B6延长了2.0和1.4天。产卵行为的电子记录结果表明,该飞虱在B1和B6上的产卵频次、一次产卵时间及总产卵时间与对照相比均无显著差异。在寄主植株可选择时,该飞虱有偏爱于B1上产卵,其上的产卵痕数、卵块数和总产卵量明显多于对照;而不嗜好于B6上产卵,其上的卵块及其卵粒数、总产卵量明显少于对照。然而,在寄主植株不可选择时,则未观察到这种差异。就卵孵化率而言,不论在寄主可选择还是不可选择时,与对照相比B1和B6对其均无显著的不利影响。  相似文献   

10.
胡桃长足象是核桃果实的大害虫,为害损失很大。1975年以来,我们在四川平武地区进行了生活习性观察和防治试验,初步明确了以下几个问题。1.胡桃长足象一年一代。11月份以成虫越冬,次年4月上旬开始活动,为害果、芽、嫩枝、叶柄,5月上旬交尾产卵于果中,一般一果一粒,8月中旬产卵结束,10月陆续死亡。当年成虫6月中旬羽化,进行为害。2.成虫有假死性和向阳性,飞翔力弱,具有与核桃树芽苞相似的保护色。3.防治胡桃长足象,应抓住越冬成虫大量出现和卵孵化盛期时进行。用每毫升含孢量二至五亿的白僵菌液或50%的三硫磷乳油、50%速灭松乳剂、82%磷胺乳剂加水一千倍喷雾,效果良好。  相似文献   

11.
昆虫母代产卵部位的选择特点直接影响到子代的生存适应性,但已有研究对冬型中国梨木虱产卵部位选择特点尚未明确。本研究调查了冬型中国梨木虱随时间变化在梨树花芽、叶芽、枝条基部、花柄、幼叶上产卵特点的变化。结果表明,冬型梨木虱产卵期约45 d,以枝条基部刻痕处着卵量最大,显著高于其他部位。冬型梨木虱产卵部位的选择随梨树的物候变化而变化:萌芽前,优先选择枝条顶芽,其次在腋芽和枝条基部刻痕处产卵;花期和展叶期,花芽、叶芽、枝条基部刻痕处着卵量下降,主要于花柄和幼叶部位产卵;冬型梨木虱产卵部位的选择顺序依次为花芽、叶芽、枝条基部、花柄、幼叶。本研究明确了冬型梨木虱在梨树不同部位产卵的变化特点,研究结果可用于指导梨木虱防控。  相似文献   

12.

Extracts from nine plant materials were tested in choice and no-choice tests as oviposition deterrents for cowpea bruchid, Callosobruchus maculatus (F.) on chickpea, Cicer arietinum L. Seed treatment with 0.1% crude extract of materials resulted in a significant reduction in ovipositional preference of the bruchid. The highest repellency was found in Rhazya stricta leaves (82%), Azadirachta indica seeds (76.8%), Heliotropium bacciferum aerial parts (59.2%) and citrus peels (58.6%). Progeny production was significantly reduced: only 11.5, 11.9, 12.4, 13.4 and 14.8% of the eggs deposited reached adulthood in R. stricta, neem seeds, Piper nigrum, citrus peels and H. bacciferum, respectively. F1 females laid significantly fewer eggs in response to R. stricta, neem seeds, Eugenia caryophyllata cloves, H. bacciferum, citrus peels and P. nigrum. Percentage reduction in F2 progeny ranged between 71.4% with R. stricta-treated seeds and 24.5% in the P. nigrum treatment.  相似文献   

13.
室内研究了梨小食心虫对蜡纸、PE保鲜膜、硫酸纸和玻璃载玻片4种基质的产卵选择性。结果发现,梨小食心虫在硫酸纸基质上的累积落卵量和卵孵化率最高,分别为70.75粒和79.39%,与蜡纸基质差异不显著(66.50粒和70.95%),但显著高于保鲜膜和玻璃两种基质(P0.05);5日龄和6日龄雌虫对硫酸纸的产卵选择率分别为33.33%和33.08%,与蜡纸基质差异不显著(32.26%和31.82%),而7日龄时对硫酸纸基质的产卵选择率为32.46%,显著高于其他3种基质。表明基质显著影响梨小食心虫的产卵场所选择,且不同日龄雌虫之间选择性存在差异,本研究结果为优化梨小食心虫人工饲养技术方案提供了依据和参考。  相似文献   

14.
BACKGROUND: The potato psyllid, Bactericera cockerelli, is a vector of Candidatus Liberibacter solanacearum, causing several diseases in solanaceous crops. Laboratory and field no‐choice and choice experiments were conducted to evaluate the repellency of kaolin particle film on adults of B. cockerelli on tomato plants that had been sprayed with kaolin particle film on the upper surface only, on the lower surface only and on both leaf surfaces. RESULTS: In no‐choice tests in the laboratory, the numbers of adults on leaves were not different between the kaolin particle film and the water control, regardless of which leaf surface(s) were treated, but numbers of eggs were lower on the leaves treated with kaolin particle film than on those treated with water. In choice tests on plants treated with water/plants treated with kaolin particle film at ratios of 1:1, 6:3 or 8:1, fewer adults and eggs were found on the leaves treated with kaolin particle film than on leaves treated with water. Under field conditions, in caged no‐choice or choice tests, fewer adults, eggs and nymphs were found on plants treated with kaolin particle film than on plants treated with water. In an uncaged test under field conditions, plants sprayed with kaolin particle film had fewer psyllids than those sprayed with water. CONCLUSION: Even though potato psyllid adults could land on plants treated with kaolin particle film when no choice was given, fewer eggs were laid. When given a choice, the psyllids avoided plants treated with kaolin particle film under laboratory and field conditions. Kaolin particle film treatment may be a useful alternative for management of potato psyllids under field conditions. Copyright © 2011 Society of Chemical Industry  相似文献   

15.
An n-hexane extract and the sesquiterpene polygodial isolated from the bark of Drimys winteri J.R. Forster & G. Forster (Winteraceae) were tested to assess their ability to inhibit settling of the aphid Nasonovia ribisnigri Mosley on lettuce leaves; assessments were made using a choice and no-choice leaf-disk assay. The n-hexane extract and the polygodial both significantly inhibited settling in the choice and no-choice tests, but their application on lettuce leaves did not result in any aphid mortality. Probing behavior of N. ribisnigri on polygodial-treated plants was assessed by means of the electrical penetration graph technique. Polygodial interfered with aphid probing behavior by reducing the total probing time, the number of probes, and the number of intracellular punctures. Aphids did not reach the sieve elements of polygodial-treated plants during the 2-h access period. Both tested compounds have the potential to be used in the development of lettuce aphid control agents to reduce the risk of virus transmission.  相似文献   

16.
山东广翅蜡蝉在青岛地区的发生规律及产卵习性   总被引:1,自引:0,他引:1  
为明确山东广翅蜡蝉Ricania shantungensis Chou et Lu在青岛地区的发生情况,于2017年4月至2018年12月,采用踏查法调查该虫在山东省青岛市的寄主范围,并采用套网袋和定点观察相结合的方法调查其年生活史及成虫产卵习性。结果表明,山东广翅蜡蝉在青岛地区的寄主有27种,其中木本植物25种,草本植物2种。山东广翅蜡蝉在青岛地区1年发生2代,以卵越冬,翌年春天5月初孵化,越冬代成虫发生期为7月1日至8月10日;第1代成虫发生期为9月23日至12月4日。第1、2代卵的高峰期分别出现于7月25日和10月30日。成虫产卵对黄栌Cotinus coggygria Scop.具有明显的嗜好性,且喜将越冬卵产在东向和南向枝条上,不仅可产卵于新生嫩枝,也可以产卵于叶片主脉。本研究结果可以为青岛乃至山东地区山东广翅蜡蝉防治提供依据。  相似文献   

17.
为探究牛角花齿蓟马Odontothrips loti的产卵选择及寄主营养和次生代谢物质对其产卵行为的影响,本研究观测了牛角花齿蓟马在苜蓿Medicago sativa、草木樨Melilotus officinalis、红豆草Onobrychis cyri和红三叶Trifolium pratense 4种豆科牧草叶片上的产卵量和卵孵化率,同时测定、分析了牧草主要营养和次生代谢物质含量与蓟马产卵选择的相关性。结果表明,无选择条件下,牛角花齿蓟马在苜蓿上产卵量最高,为59.1粒/复叶,其次是草木樨,15.7粒/复叶,在红豆草和红三叶上的产卵量仅为0.9粒/复叶和1.1粒/复叶。卵孵化率在苜蓿上最高,为85.05%,在草木樨和红豆草上分别为40.09%和39.18%,红三叶上最低,为5.48%。两两选择条件下,牛角花齿蓟马明显偏好在苜蓿叶片上产卵,在其他牧草叶片上不产卵或产卵量极低。相关性分析表明,牛角花齿蓟马的产卵量与寄主可溶性蛋白含量显著正相关(r=0.722,P=0.002),卵孵化率与可溶性蛋白(r=0.673,P=0.004)和淀粉(r=0.586,P=0.017)含量显著正相关。牛...  相似文献   

18.
The toxicity of six pesticides (four insecticides and two fungicides) to Orius majusculus (Reuter) (Hemiptera: Anthocoridae) adults and nymphs was determined using different exposure methods. Mortality upon topical exposure to abamectin, endosulfan and spinosad at recommended field doses ranged from 56% to 100% after 24 h. However, in leaf residue tests, toxicity to both life stages decreased significantly, ranging from 0% to 33% mortality. Benomyl and copper salts + mancozeb (fungicides) were much less toxic to O. majusculus, with less than 15% mortality of either adults or nymphs in topical and residue bioassays. In persistent toxicity tests, insects were exposed to the same three insecticides for 4 days; mortality varied from 38% to 100%. Egg hatching was not significantly affected when abamectin, endosulfan and spinosad were topically applied. Number of eggs laid per female in choice and no-choice tests did not differ significantly from the control. The insecticides did not show considerable repellent effect in the choice tests. Topical, residue and systemic uptake methods were also compared to determine the differences in the toxicity levels of imidacloprid, a systemic insecticide. However, 100% mortality occurred with all methods.  相似文献   

19.
ABSTRACT Pear decline (PD) is an important disease of Pyrus communis fruiting cultivars in Europe, Asia, and the Americas. PD is caused by a phloem-limited phytoplasma that, in California, is transmitted from diseased to healthy trees by pear psylla, Cacopsylla pyricola. The percentage of phytoplasma-infected pear psylla has never been assessed in the United States in field-collected insects. Pear psylla were collected monthly from PD-infected trees from three orchards in northern California. Individual psylla were tested for the presence of PD phytoplasma, using both a quantitative DNA hybridization and PD phytoplasma-specific polymerase chain reaction (PCR) assays. The percentage of infected psylla ranged from 0 to 45% depending on the orchard, the month and year collected, and the method of detection. The PD phytoplasma was detected in both the winterform and summerform pear psylla. Significantly more infected psylla were detected with PCR than with DNA hybridization analysis in two of the three orchards. The number of PD phytoplasma per pear psylla was estimated to range from 1 x 10(6) to 8.2 x 10(7). The percentage of PD-infected pear psylla found in the three northern California pear orchards suggests that both winterform and summerform pear psylla could be important in the transmission of PD.  相似文献   

20.
A 2-year study was conducted to determine the widespread occurrence of overwintered conidial inoculum of Venturia inaequalis and its impact on the apple scab control in 18 apple orchards (organic and integrated) with various levels of scab in the Netherlands. Autumn assessments of scab lesions showed that the integrated orchards had a significantly lower scab incidence (<20%) compared to that of the organic orchards (>60%). At the bud-break phenological stage, the mean numbers of nonviable and viable conidia on 1 cm pieces of shoots ranged from 1 to about 90 and from 6 to more than 1000 in the integrated and the organic orchards, respectively, for both years. However, viable conidia on shoots were found only in 2 integrated and 6 organic orchards out of the 18 and the viability of conidia was below 2%. The mean numbers of viable and nonviable conidia per 100 buds ranged from 24 to more than 1000 and from 230 to almost 5000 in the integrated and the organic orchards, respectively, for both years. In both years, some 60–85% of the conidia was found on the outer bud scales. The percentage viability associated with the outer bud tissues was below 2% for all the orchards. However, the percentage of viable conidia within the inner bud tissues ranged from 0% to 6% in the integrated and from 2% to 11% in the organic orchards for both years. Differences between the organic and the integrated orchards were clearly demonstrated for overwintered conidia associated with both shoot and bud samples. The relationship between autumn scab incidence and numbers of overwintered conidia associated with shoots or buds was exponential. If the autumn scab incidence was above 40%, then the number of overwintered conidia markedly increased. We conclude that specific treatments for overwintering conidia of Venturia inaequalis may not be necessary in integrated orchards with a low scab incidence in the previous autumn. However, the risk of early scab epidemics initiated by overwintered conidia potentially is high in organic orchards. Preventative measures in early spring and also in the previous year must be established in these orchards.  相似文献   

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