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1.
The phenology and natural enemies of Nemolecanium graniformis (Wunn) (Homoptera: Coccidae) in infesting Abies cephalonica, were studied in Greece during 1998–1999. This oviparous species develops one generation per year in Central Greece (Attica) and overwinters as 2nd instar nymph. Young adult females appear by the end of July, and the first instar nymphs by the middle of August. By the middle of October, the whole population of the scale is recorded as 2nd instar nymphs. The parasitoids Coccophagus lycimnia (Walker), Coccophagus Westwood sp., Aphycoides Mercet sp. and the predator Exochomus quadripustulatus L. (Coleoptera: Coccinellidae), were observed as natural enemies of the scale. The average fecundity of N. graniformis was 188.4 eggs.  相似文献   

2.
Two hot and dry weather periods during mid-spring and early summer caused severe drought-stress to barley groves in many districts of the Czech Republic in 2000. Although not generally taken into consideration as an injury-increasing factor, the Russian wheat aphid (=RWA), Diuraphis noxia (Kurdj.), was discovered to contribute significantly to injury in the ripening stage of spring barley as well as to the substantial decrease of yield (up to 30–40% of the calculated mean, in some districts). RWA increased considerably not only in the lowland banker areas but also in the higher altitudes, values in the latter case then manifesting those found in the lowland banker areas in the previous years.  相似文献   

3.
Different concentrations of Neem Azal-T/S, an insect growth regulator (IGR) (antiecdysone) and various other insecticides were tested against the pistachio psyllid (Agonoscena targionii) affecting pistachio (Pistacia vera L.), in northern Syria. From 1997–99, three applications were made annually, in April, May, June or July. Results revealed that Neem Azal-T/S, at the rate of 0.5 and 0.7%, Flufenoxuron, Teflubenzuron, and the antagonistic fungus Beauveria bassiana Bals. were highly effective against the psyllid especially on the 1st and 2nd nymph instars in the April application. The possibilities of using these pesticides in integrated management against pistachio psyllid in Syria are discussed.  相似文献   

4.
Different concentrations of Neem Azal-T/S, an insect growth regulator (IGR) (antiecdysone) and various other insecticides were tested against the pistachio psyllid (Agonoscena targionii) affecting pistachio (Pistacia vera L.), in northern Syria. From 1997–99, three applications were made annually, in April, May, June or July. Results revealed that Neem Azal-T/S, at the rate of 0.5 and 0.7%, Flufenoxuron, Teflubenzuron, and the antagonistic fungus Beauveria bassiana Bals. were highly effective against the psyllid especially on the 1st and 2nd nymph instars in the April application. The possibilities of using these pesticides in integrated management against pistachio psyllid in Syria are discussed.  相似文献   

5.
The development of the red palm weevil, Rhynchophorus ferrugineus (Olivier) was investigated on a newly developed semiartificial diet as compared with two natural diets namely sugarcane stem and banana fruit. The weevil was successfully maintained on these diets and duration of the life cycle for males and females, respectively were 164.97 and 194.61 days on the semiartificial diet, 192.5 and 186.5 days on banana, and 172.00 and 170.00 days on sugarcane. The average egg production per female was shown to be significantly higher on the semiartificial diet, being 184.00±18.68 eggs compared with an average of 125.00±11.97 and 133.00±15.21 eggs on banana and sugarcane, respectively. The fertility ranged between 94–100% in those eggs deposited by females previously reared on the tested diets. The developed semiartificial diet was shown to be suitable for maintaining laboratory colonies of the red palm weevil, and it can substitute natural diets.  相似文献   

6.
Analytical studies were conducted on the species composition of galls occurring on the leaves of Salix purpurea L. in the Ojców National Park in 1999–2000. The species composition of galls was identical in two consecutive years. Galls were caused by 5species (a total of 480galls). The most numerous species in both years was Pontania viminalis (L.). Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Pontania dolichura (Thoms.) and P. viminalis (L.) in 1999 as well as Phyllocolpa leucaspis (Tischb.) and P. viminalis (L.) in 2000.  相似文献   

7.
The parasitoids of Saperda populnea (L.) (Col.: Cerambycidae) were studied in Bulgaria during the period 1997–2001. Galls with pest larvae were collected from young aspen trees at eight locations (Sofia, Kokaliane, Plana, Churek, Gorni Lom, Gintzi, Dolno Kamartzi and Klisura) and examined under laboratory conditions. Four species were reared from 1118 galls containing overwintering pest larvae: Iphiaulax impostor (Scop.) (Hym.: Braconidae), Dolichomitus populneus (Ratz.), Schreineria populnea (Gir.) (Hym.: Ichneumonidae) and Billaea irrorata (Meig.) (Dipt.: Tachinidae). All of the parasitoids were solitary. Schreineria populnea was found as a new parasitoid of the host in Bulgaria. B. irrorata emerged mainly from late-stage S. populnea larvae; the remaining species from both early- and mid-stage larvae. In the parasitoid complex of S. populnea, the most numerous were B. irrorata (59.8%) and D. populneus (29.4%). The percentage of host larval parasitism varied from 2.4 to 33.3, with an average of 9.7%. B. irrorata was the most important in reducing the pest number. The average mortality of S. populnea caused by the tachinid was 5.8%, and the highest mortality observed in individual study was 20.2%.  相似文献   

8.
An outbreak on apple permitted a closer look at Coenorhinus pauxillus (Germar) (Col.: Attelabidae). The adult weevils emerge from mid-March onwards and attack the first unfolding leaves. Infested leaves drop when the larvae are in the 1st or 2nd instar, and it takes a further 4 weeks before the larvae are ready to pupate. Rearing of field-collected eggs and larvae is described. Leaf decomposition is an essential condition for pupation, as the fully-grown larvae do not leave their mine actively. Part of the population pupates more or less immediately and produces adult weevils in autumn. However, up to 70% of the weevils remain in prolonged diapause; their pupation does not take place before the summer of the following year. Damage by the weevil involves not only the loss of leaves of flower clusters and shoots, but also feeding damage to young fruits. Two parasitoids were found. Observations indicate that 3–4 subsequently more abundant generations of Anaphes brachygaster Debauche (Hym.: Mymaridae) develop in eggs of C. pauxillus. Probles brevicornisHorstmann (Hym.: Ichneumonidae, Tersilochinae) emerges in May and oviposits in young weevil larvae on the tree. The parasitoid does not develop into a pupa until its host starts pupating. The outbreak of apple leaf cutter did not decline over three years, but did not spread into adjacent plantings.  相似文献   

9.
Two hot and dry weather periods during mid-spring and early summer caused severe drought-stress to barley groves in many districts of the Czech Republic in 2000. Although not generally taken into consideration as an injury-increasing factor, the Russian wheat aphid (=RWA), Diuraphis noxia (Kurdj.), was discovered to contribute significantly to injury in the ripening stage of spring barley as well as to the substantial decrease of yield (up to 30–40% of the calculated mean, in some districts). RWA increased considerably not only in the lowland banker areas but also in the higher altitudes, values in the latter case then manifesting those found in the lowland banker areas in the previous years.  相似文献   

10.
A 4-year (1996–99) survey of the biology of L. serricorne (F) (Coleoptera, Anobiidae) on stored tobacco has taken place in Thessaloniki, northern Greece. For the trapping of the adults, pheromone ('New Serrico' and 'Black Stripe Moth') as well as electric (black light) traps were used. The first generation adults emerging from larvae hibernating inside the tobacco bales appeared flying on the 17/5, 16/5, 28/4, and 30/4 of the years 1996, 1997, 1998, and 1999, respectively. In parallel observations, adults inside the bales were found on the 14/5, 12/5, 23/4, and 26/4 of the above-mentioned years, respectively. Termination of flights, in all the years concerned, took place during October or November, while the last flights of November were recorded in temperatures of about 13°C.  相似文献   

11.
The pupal duration of the red palm weevil, Rhynchophorus ferrugineus (Oliv.) at two different temperatures revealed that the thermal threshold is –2.3°C, while the thermal constant is 423 degree days. Around 20.7 cycles of weevil emergence per year have been predicted in Egypt. A temperature between 44–45°C was found to be the higher threshold at which the pupae are killed. The heat units required for the pupal development were utilized to predict the dates of adult emergence throughout the year.  相似文献   

12.
Ancient Egyptian insect relics were accidentally enclosed in embalming resin which leaked from a priest's mummy and solidified on the floor of a wooden coffin from the end of the XVIIIth Dynasty (presumably 1323–1295 BC). The preserved insect relics were blowflies (Calliphoridae) recognized as Chrysomya marginalis or Chrysomya megacephala whose larvae had developed by feeding on the deceased's body prior to mummification as well as furniture beetles (Anobiidae) being either Oligomerus ptilinoides or Priobium carpini whose larvae had ingested the coniferous wood of the coffin. It is most likely that the human corpse and coffin were first attacked by the blowflies and furniture beetles prior to embalming, while infestation of the insect remains and textiles by Anthrenus sp. (Dermestidae) occurred in our time.  相似文献   

13.
Species composition of galls on the leaves of Ulmus laevis Pall. was analysed in 2001–02 in the Mogilski Forest – near an urban agglomeration of Kraków. A total of 5830 galls were found. The galls were caused by 5 insect or mite species. Aceria ulmicola brevipunctata (Nalepa) was the most abundant species in both years.The index of occurrence frequency and Agrell's index of species co-occurrence have been calculated. The index of occurrence frequency (F) reached the highest value in the case of A. ulmicola brevipunctata, namely 1.740, in 2001, and the lowest value, i.e. 0.00005 for Schizoneura ulmi (Linné), in 2001. Agrell's index of species co-occurrence reached the highest values, i.e. 0.500, in the case of A. ulmicola brevipunctata and Physemocecis ulmi (Kieffer), in 2002, and the lowest one, namely 0.050 for A. ulmicola brevipunctata and Schizoneura ulmi, in 2001.  相似文献   

14.
A study was conducted on the insects infesting seeds and cones of Abies alba Mill. in the Gorce National Park, in southern Poland during 1996–1998. A total of 856 cones were collected from 66 trees growing at 11 sites located in partially or strictly protected forest reserves. Of this sample, 217 cones with 54,958 seeds were dissected. This study yielded 5,816 specimens of insects, namely: seminiphagous Resseliella piceae Seitn., Megastigmus suspectus Borr. as well as conophagous Earomyia impossibile Morge, Barbara herrichiana Obr. and Dioryctria abietella (Den. et Schiff.). The most abundant species was R. piceae with 4,186 individuals. The index of cone infestation was calculated. It showed great variability between forest reserves and study-years. The numbers of insect individuals, numbers of viable and infertile seeds, and seeds damaged by M. suspectus and R. piceae, in both strict and partial reserves in the consecutive years were compared statistically. The test of significant differences between two frequencies at 0.05 level was used in statistical analysis. In both strict and partial reserves, statistically significant differences were found between studied variables.  相似文献   

15.
The occurrence frequency of galls caused by insects and mites on the leaves of Fraxinus excelsior L. was investigated, based on leaf samples collected in the Ojców National Park in 2000–2001. The species composition of galls was identical in two consecutive years. Galls were caused by 5 species a total of 2881 galls. The most numerous species was Dasineura fraxinea (Kieffer) in both years.Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Dasineura fraxinea and Vasates fraxini (Nalepa) in 2000 as well as D. fraxinea and Psyllopsis fraxini (L.) in 2001.  相似文献   

16.
Canningia tomici sp. n. (Microsporidia, Unikaryonidae) infects the midgut epithelium, the gut muscules, Malpighian tubules, connective tissues, adipose tissues and the gonads of the pine shoot beetle, Tomicus piniperda (L.) (Coleoptera, Scolytidae). The infection is present in populations of Tomicus piniperda in Europe and in the United States. Uninucleate oval single spores occur in two sizes: 2.8±0.4× 1.4±0.4m and 3.8±0.3×2.0±0.2m. The polar filament of this microsporidium is fixed subapically in a flat anchoring disc. The thick posterior lamellae of the binary polaroplast are asymmetric due to the lateral fixation of the polar filament.  相似文献   

17.
The present paper deals with laboratory studies on side-effects of the mixed biocide GCSC-BtA on Plutella xylostella (L.) (Lep., Plutellidae) and its predators, e.g. Amblyseius longispinosus (Evans) (Acari, Phytoseiidae), Erigonidium graminicola (Sundvall) (Araneae, Linyphiidae), Orius similis Zheng (Het., Anthocoridae) and Coccinella septempunctata L.(Col., Coccinellidae), in comparison to the commercial insecticides, e.g. Abamectin, Tebufenozide, Dichlorvos, Cartap and Lambda-cyhalothrin.The results showed that GCSC-BtA was highly toxic to the 3rd instar of P. xylostella with 91.18% mortality, followed by Cartap with 84.38%, Abamectin with 78.00%, Tebufenozide with 75.57%, Lambda-cyhalothrin with 63.75% and Dichlorvos with 50.86% mortality. On the other hand, GCSC-BtA was found to be comparatively less toxic to the predators, causing 31.11%, 13.33%, 11.54% and 6.00% mortalities in A. longispinosus, E. graminicola, O. similis and C. septempunctata, respectively. For comparison, the mortalities recorded for Abamectin, Tebufenozide, Dichlorvos, Cartap, Lambda-cyhalothrin were 72.94%, 55.55%, 70.00%, 53.26% and 98.85% in A. longispinosus, 46.51%, 55.10%, 60.00%, 46.00% and 73.68% in E. graminicola, 22.00%, 16.00%, 35.71%, 26.78% and 81.03% in O. similis, 15.55%, 19.64%, 28.00%, 16.66% and 41.79% in C. septempunctata, respectively.  相似文献   

18.
The parasitoids of Saperda populnea (L.) (Col.: Cerambycidae) were studied in Bulgaria during the period 1997–2001. Galls with pest larvae were collected from young aspen trees at eight locations (Sofia, Kokaliane, Plana, Churek, Gorni Lom, Gintzi, Dolno Kamartzi and Klisura) and examined under laboratory conditions. Four species were reared from 1118 galls containing overwintering pest larvae: Iphiaulax impostor (Scop.) (Hym.: Braconidae), Dolichomitus populneus (Ratz.), Schreineria populnea (Gir.) (Hym.: Ichneumonidae) and Billaea irrorata (Meig.) (Dipt.: Tachinidae). All of the parasitoids were solitary. Schreineria populnea was found as a new parasitoid of the host in Bulgaria. B. irrorata emerged mainly from late-stage S. populnea larvae; the remaining species from both early- and mid-stage larvae. In the parasitoid complex of S. populnea, the most numerous were B. irrorata (59.8%) and D. populneus (29.4%). The percentage of host larval parasitism varied from 2.4 to 33.3, with an average of 9.7%. B. irrorata was the most important in reducing the pest number. The average mortality of S. populnea caused by the tachinid was 5.8%, and the highest mortality observed in individual study was 20.2%.  相似文献   

19.
During 1996 and 1997, populations of aphids and whiteflies and their parasites were studied in plastic greenhouses under a chemical control program and in those free of pesticides. In the greenhouses free of pesticides, the parasite A. colemani destroyed 14.7% of the aphids. B. tabaci had no effect on the cucumbers during the spring cultivation. However, it attacked the autumn cultivation. The parasite E. mundus killed 30% of these nymphs. The parasite A. colemani parasitized up to 10% of aphids on tomato plants in greenhouses free of chemical pesticides. The parasite E. mundus killed 15.7% of whitefly nymphs.  相似文献   

20.
A study was conducted on the insects infesting seeds and cones of Abies alba Mill. in the Gorce National Park, in southern Poland during 1996–1998. A total of 856 cones were collected from 66 trees growing at 11 sites located in partially or strictly protected forest reserves. Of this sample, 217 cones with 54,958 seeds were dissected. This study yielded 5,816 specimens of insects, namely: seminiphagous Resseliella piceae Seitn., Megastigmus suspectus Borr. as well as conophagous Earomyia impossibile Morge, Barbara herrichiana Obr. and Dioryctria abietella (Den. et Schiff.). The most abundant species was R. piceae with 4,186 individuals. The index of cone infestation was calculated. It showed great variability between forest reserves and study-years. The numbers of insect individuals, numbers of viable and infertile seeds, and seeds damaged by M. suspectus and R. piceae, in both strict and partial reserves in the consecutive years were compared statistically. The test of significant differences between two frequencies at 0.05 level was used in statistical analysis. In both strict and partial reserves, statistically significant differences were found between studied variables.  相似文献   

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