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In Egypt, Trichogramma evanescens Westwood (TE) is extensively used in inundative releases against a number of lepidopterous pests of several crops. However, the wasp had not been collected from olive groves. Field trials on the use of commercially available TE against the olive moth, Prays oleae (Bern.) (OM) were carried out for three successive years (2002–2004). The objective of this study was to evaluate the efficacy of inundative releases of this wasp on damage reduction. The obtained results were encouraging since OM attacks were reduced by 42.9,71 and 69.9% and TE-treated trees yielded significantly bigger olive fruits by 10.5 and 12.5% than untreated trees in 2002 and 2004 olive seasons, respectively. However, parasitization levels indicated that the wasp is not well adapted to local environmental conditions of olive groves. The suggested measure to improve the quality of released wasps is to mass release of local wasps isolated during the present study, i.e., T. cordubensis Vargas and Cabello and T. euproctidis Girault.  相似文献   

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The adaptation of the primary internal parasitoid,Trichogramma evanescens (Westw.), as an egg parasitoid ofLobesia botrana (Den. & Schiff.) was the first report in Alexandria region, Egypt. The life-span of this parasitoid on eggs ofL. botrana andSitotroga cerealella Ol. was investigated. The duration from egg to adult, longevity of adult stage, sex-ratio and total life cycle each of the two hosts were recorded. The ovipositional periods of mated females ofT. evanescens on egg ofL. botrana at 27±2co and 75±2% R.H. were studied. Also, percentages of parasitism byT. evanescens ranged from 22%–64% on the eggs ofL. botrana. Therefore, this parasitoid was very efficient as a biocontrol agent against the most serious grape pestL. botrana in Egypt.  相似文献   

4.
Non-choice laboratory experiments were conducted to evaluate the influence of host acceptance, previous rearing host, host age and the contact time between parasitoids and host on the efficacy of Trichogramma cacoeciae Marchal and T. principum Sug. et Sor. against the codling moth Cydia pomonella. The tendency of T. cacoeciae and T. principum females to attack the codling moth was similar to E. kuehniella, and it was not affected by the previous rearing host. T. cacoeciae showed a greater preference for codling moth eggs than T. principum. A high mean number of emerged F1 progeny was observed when both parasitoids were sequentially reared on codling moths. Codling moth acceptance, the number of parasitized eggs and the number of emerged progeny were higher when younger codling moth eggs were offered. The tendency of female parasitoids to oviposit remained unchanged when the contact time with the host was prolonged. When the contact time was increased, the number of parasitized eggs and emerged offspring was higher. The results showed that the codling moth fertility (egg hatch) was reduced when younger eggs were offered and when the contact time with the parasitoids was increased. T. cacoeciae was more efficient in reducing codling moth fertility. The current study provided essential information necessary to increase the efficiency of T. cacoeciae and T. principum against the codling moth.  相似文献   

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Classic biological control is generally understood as an environmentally safe practice of insect pest management. We investigated the overwintering abilities of Trichogramma brassicae Bezd. and T. cacoeciae Marchall in Tekirda Turkey. Parasitized eggs of Ephestia kuehniella Zell (Lep.: Pyralidae) by T. cacoeciae and T. cacoeciae were exposed under outdoor conditions between 17 August and 9 October. Emergence of T. brassicae and T. cacoeciae for the five exposure dates occurred in the same year. An emergence of 99% was observed in the following offspring for all of the tested parasitoid species exposed on 17 September. For eggs that were parasitized later than 9 November 2003, the emergence of parasitoids was in spring, on 19 March 2004. We found that T. brassica and T. cacoeciae were able to overwinter successfully on E. kuehniella. Fecundity of T. brassicae and T. cacoeciae females that overwintered on E. kuehniella was significantly different from the fecundity of control females that were reared under optimal conditions at 25°C. Our results demonstrate that the egg parasitoids T. brassicae and T. cacoeciae are able to overwinter successfully in Turkey .  相似文献   

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For the control of the aphid speciesMacrosiphum euphorbiae, an important aphid species on greenhouse cut roses in Austria, with the parasitoidAphelinus abdominalis, trials were carried out in the rose varieties Frisco, Kardinal and Vivaldi at a commercial producer on a greenhouse area of 630 to 700m2. Both the inundative release of 9,6A. abdominalis/m2 in total and the release of 2,2A. abdominalis/m2 in total, within an open rearing system were investigated and the percentage of infested rose shoots in combination with the degree of infestation were evaluated. The results showed that an effective reduction of present or newly developing aphid populations was possible for several weeks under the conditions of a commercial greenhouse production. The amount of insecticides used against aphids decreased by up to 75% in comparison to greenhouses were only chemical pest control was carried out. The suitability of the different introduction methods ofA. abdominalis for the control of aphids on greenhouse cut roses is discussed.  相似文献   

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Bean-weevil (Bruchus chinensis L.) is commonly found in Sind region of Pakistan and it severely damages Mong seeds (Phaseolus mungo L.), and some other pulses in storage conditions. The parasitoidApanteles flavipes (Cam.), a gregarious Braconid parasite of Bean-weevil was reared under laboratory conditions with a view to exploiting it for the biological control techniques to be reported for the first time in Pakistan. This parasite completes its whole life cycle inside the body of the host by completing a number of generations in a year, and it successfully parasitisesBruchus spp. larvae inside the seed body; and its life cycle entirely depends upon the environmental factors like temperature and humidity as well as on the physiological condition of the host. It parasitised upto 45% in field population and 83% under laboratory conditions.  相似文献   

9.
Moth species Ephestia kuehniella and Sitotroga cerealella are serious pests in cereal-based food processing facilities and stores in Turkey. Control of these pests is undertaken by regular space treatment of infested areas with pesticides. An alternative control method could be the release of parasitic wasps of the genus Trichogramma. In laboratory tests, we use T. evanescens as a parasitic wasp reared on the eggs of Ephestia kuehniella. Adult wasps emerging from the host were maintained in glass tubes at 27±1° C, 60–70±5% r.h and L14:D10 and fed on honey solution. Adults of T. evanescens in vials without food enclosed from host eggs and all died within 1.8days; in comparison, in vials with honey, live adults were evident for 15.2days. Fresh (6–48h) and old (72–96h) host eggs were offered to T. evanescens and fresh eggs were more accepted than old. Host acceptance of females with males in vials was better than without males. The number of females in the vials also influenced the parasitization rate and single female parasitized more eggs. Adults living in light regime (L14:D10 and L6:D18) parasitized more eggs than in total darkness. Results are discussed with relation to enhancing parasitoid effectiveness in biological control in processing facilities and mills.  相似文献   

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The present work was conducted to evaluate the efficacy of Trichogramma evanescens (Westwood) in controlling the European grape berry moth Lobesia botrana (Den. & Schiff.) in two vineyards, in El-Beheira and El-Gharbia Governorates, northern Egypt during the 2004 and 2005 seasons. T. evanescens was mass produced on Sitotroga cerealella (Olivier) eggs in National Research Center in Egypt. The horizontal and vertical searching activity of T. evanescens was studied to determine the proper way of distributing the Trichogramma cards in vineyards in 2004. Field experiments were also conducted to evaluate inundative releases of T. evanescens to control L. botrana on large scale in 2005. Parasitism by T. evanescens on L. botrana eggs was greatly affected with the horizontal or vertical distance from the release points. Parasitism reached over 97% and reduction percents of infestation were caused by the pest reached 96.8% in treated plots. A significant increase in the crop was achieved in treated plots. The results showed that the release cards should be distributed in every three grape rows and on height 130–170 cm to obtain good parasitism rates. T. evanescens could be a potential candidate for biological control of L. botrana in vineyards.  相似文献   

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The efficacy of a new class of insecticide (chloronicotinyl) Mospilan 20 SP (a.?i. acetamiprid), compared with Lannate 90 SL (a.?i. methomyl) and Applaud WP 25 (a.?i. buprofezin), in glasshouse control of whitefly (Trialeurodes vaporariorum) on tomatoes, was investigated. All investigated insecticides significantly decreased the number of whitefly larvae, compared with untreated plots where population density grew during the trial. Based on statistical analysis, efficacy of all insecticides on whitefly larvae were in the same category. Some differences occurred 7 days after the third treatment. Deposited egg number was significantly different between checks and each insecticide plot. Efficacy of investigated insecticides, evaluated according to deposited egg number, was also good and in the same category.  相似文献   

12.
陈定如 《广东园林》2007,29(3):79-80
水翁(水泱)桃金娘科常绿乔木,高10~16m。枝下高2~4m,树皮厚,灰褐色,嫩枝压扁或近四棱形;树冠圆形。叶对生,薄革质,长圆形至椭圆形,长8~12cm,宽4~8cm,  相似文献   

13.
During several years the density of nests ofFormica spp. was determined in the State Forests of the Bavarian Alps using the statistical methods of strip survey. The measured density was between 0.32 and 17.78 nests/ha and the calculated abundance on a total forest area of 108269 ha were 221212 nests ofFormica spp., 85% of which wereF. aquilonia and 15%F. lugubris. The typical wood ant species of the lowland were very rare in the mountain region and their nests made up less than 1%. The most important habitat factors (soil, altitude and exposition as well as type, age and density of the stands) were investigated in regard to their impact on the distribution of mountain ants species. Results are summarized in tables. It could be shown that the stand, especially its density was the most important factor which determined the presence of mountain ant species in their colonization region between 700 and 1,800m above NN.  相似文献   

14.
The effective threshold rate of application of Dipel 2X was 250g/f. Incorporation of some chemical additives such as calcium sulphate (CaSO4) or calcium oxide (CaO) significantly potentiated the effectiveness of Dipel 2X on larval population. The addition of calcium carbonate (CaCO3) and zinc sulphate (ZnSO4) to Dipel 2X greatly reduced the larval population and led to a significant increase in the yield of some vegetable crops. Dipel 2X baits at 250g/f were almost as effective as the chemical insecticide Hostathion when used at 1.5l/f in controllingA. ypsilon larvae attacking vegetable crops. Control of the greasy cutwormAgrotis ypsilon population was better achieved when the biological control agent Dipel 2X was used as baits.  相似文献   

15.
Weekly samples of the cutworm,Agrotis ipsilon Rott. larvae were collected for 3 successive season 1983/84–1985/86 from 3 Governorates in middle Egypt to survey and evaluate the role of parasitoids in suppressing the pest population.Two gregarious internal larval parasitoids were recorded,Apanteles ruficrus Hal. andMeteorus rubens Nees. (Hymenoptera, Braconidae). Percentages of parasitism were estimated. They reached 20.2, 22.2 and 24.7% in seasons 1983/84, 1984/85 and 1985/86, respectively, with an average of 22.5% (10.3%A. ruficrus and 12.2%M. rubens). The highest rates of parasitism were recorded in March and April.
Zusammenfassung Wöchentliche Aufsammlungen der Raupen vonA. ipsilon während der Jahre 1983/84 bis 1985/86 im mittleren Ägypten erbrachten zwei gregäre Endoparasitoiden,Apanteles ruficrus Hal. undMeteorus rubens Nees. (beide Hym., Braconidae). Sie erreichen zusammen in den 3 Jahren 20,2, 22,2 und 24,7%, i.M. 22,5% (A. ruficrus=10,3%, undM. rubens=12,2%). Die höchsten Parasitierungsraten wurden im März und April festgestellt.


With one figure  相似文献   

16.
The daily survival rate was investigated ofTrichogramma platneri Nag. wasps supplied with flowers (both with and without anthers) of avocado cv. Ettinger and cv. Fuerte, anthers of avocado flowers, or flowers ofOxalis cernua, Mercurialis annua andEuphorbia sp. The life span of wasps supplied with anthers or weed flowers was less than 24 hours, whereas it was longer on avocado. However, none of the avocado varieties appeared outstanding in sustaining the wasps. It follows that nectar is the wasp's preferred or only source of food.  相似文献   

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Zusammenfassung In den Jahren 1977 bis 1979 im Raum Seefeld-Leutasch, Nordtirol, in Gebirgs-Tannenmischwäldern durchgeführte Untersuchungen über bösartige Tannenläuse (Adelgidae) ergaben, daß als einzige Art dortDreyfusia nordmannianae auftrat. Dabei konnten sich Stammläuse auch an Trieben weiterentwickeln. Die Eiablage fand zwischen Anfang Mai und Anfang Juni, das Schlüpfen der Neosistentes zwischen Mitte Mai und Ende Juli statt. Die Zahl der Neosistentes übertraf jene der Neoprogredientes beträchtlich. Der Besatz der Tannen mitDreyfusia war an sonnigen Standorten, verbunden mit Waldweide, besonders hoch. Im Raum Seefeld-Leutasch was der Anteil der vonDreyfusia befallenen Tannen deutlich geringer als im Raum Kufstein, doch starben im Raum Seefeld dreimal so viele Bäume ab wie im Raum Kufstein.
Studies on taxonomy, development and damages of the balsam woolly aphid, Dreyfusia nordmannianae (Eckst.) in the area of Seefeld-Leutasch (the Northern Tyrol)
Investigations which were made in 1977–1979 in the alp mountains around Seefeld on the Adelgidae sucking on silver fir showed that there wasDreyfusia nordmannianae only. Time of egg laying was from early May till early June, and of emergence of the neosistentes from middle May till late July. The number of neosistentes was much greater than those of neoprogredientes. Most aphids were to be found in those stations where there was most light and wood grazing. In the area of SeefeldD. nordmannianae attacked the firs in a less extent than in the area of Kufstein, but in the former the fir trees died three times more than in the latter.


Mit einer Abbildung und 4 Tabellen

Teil einer Dissertation am Institut für Zoologie der Universität Innsbruck, 1980.  相似文献   

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Diadegma semiclausum was reared in the laboratory on 2nd and 3rd instar larvae ofPlutella xylostella. At 25°C, the incubation period of the parasite's egg was 38h; the following stages lasted 5.4 days (5 instars), 33h (pre-pupa), and 5.9 days (pupa). Superparasitism occurred but only one parasite developed from one host larva. Sex ratio inD. semiclausum was found to be 11 in nature as well as in laboratory. The daily and total rate of eggs deposited per female were 13.6 and 164.2, respectively. The parasite male and female, fed on honey, lived for 11.2 and 14.6 days, respectively. Laboratory trials failed to rearD. semiclausum on certain lepidopterous larvae other thanP. xylostella. Percentages of parasitism byD. semiclausum inP. xylostella larvae collected from cabbage fields during 1982 ranged between 0 and 66%.
Zusammenfassung Diadegma semiclausum wurde im Labor in L2- und L3-Raupen vonPlutella xylostella gezüchtet. Bei 25°C dauerte die Entwicklung 1,6 (Ei), 5,4 (L1–L5), 1,4 (Präpuppe) und 5,9 (Puppe) Tage. Superparasitismus kam vor, doch entwickelte sich nur jeweils eine Parasitenlarve. Das Geschlechterverhältnis vonD. semiclausum betrug im Freiland und im Labor 11. Die tägliche und die Gesamtzahl an abgelegten Eiern betrugen 13,6 und 164,2. Bei Fütterung mit Honig lebten die männlichen Parasiten i.M. 11,2, die weiblichen i. M. 14,6 Tage. Die Laborversuche zeigten, daßD. semiclausum sich ausschließlich ausP. xylostella-Raupen ziehen ließ. Die Parasitierungsquoten vonD. semiclausum inP. xylostella variierten bei Raupen von Kohlfeldern aus verschiedenen Landesteilen 1982 zwischen 0 und 66%.
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