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1.
Abstract

A ten‐year survey of phytophagous insects associated with Lantana spp. (chiefly L. tiliaefolia Cham, and L. glutinosa Poepp.) in Brazil, yielded 345 species from eight orders. Half of the total species collected were Coleoptera, with Chrysomelidae being the most important family. Other important families were the Curculionidae and, in the Lepidoptera, Geometridae, Arctiidae and Noctuidae. More than 90% of insect species fed on the vegetative parts of the plant, with almost two‐thirds of these chewing holes in leaves, and fewer than 10% attacking the flowers and fruits. Woody stem borers were rare, constituting only 2% of the total insect species collected. The present status of biological control of lantana in Australia is reviewed together with the prospects of importing further biological control candidates from Brazil.  相似文献   

2.
Abstract

The development of resistance to insecticides and the hazards inherent in their use present ever-increasing problems in insect control today. The difficulties and dangers have given impetus to research on other means of combating pests. Australia has always been prominent in the field of biological control, and the CSIRO Division of Entomology is an important centre, keenly seeking controls for both insects and weeds. Progress in the search for and establishment of parasites of Sirex, the pine pest, was described in Rural Research 64. This article reviews six other projects of particular interest, namely those involving potato moth, buffalo fly, white wax scale, green vegetable bug, lantana, and skeleton-weed.  相似文献   

3.
The natural lipophilic amides piperine and piperiline were isolated from Piper nigrum L (Piperaceae). Piperine was hydrolysed into piperic acid (85% yield) which was converted into 16 amides (28–89% yield). The contact toxicity of all synthetic amides, and also that of piperine and piperiline, at the dose 10 µg per insect, was evaluated for the Brazilian economically important insects Ascia monuste orseis Latr, Acanthoscelides obtectus Say, Brevicoryne brassicae L, Protopolybia exigua DeSaus and Cornitermes cumulans Kollar. The results demontrated that the insects have different sensivities to the various amides, with mortality ranging from 0 to 97.5% according to the compound and insect species. © 2000 Society of Chemical Industry  相似文献   

4.
Abstract

Mobility results in movement of insects from their birth place (emigration) to another site (immigration). The scale, both in time and in space, on which such migration occurs may determine rates of increase or decrease in numbers in a fixed geographical area or plot. This is self evident in the case of mobile insects, such as locusts. Other documented examples include the spruce budworm in Canada and the Queensland fruit fly.

In the Sudan Gezira the distribution of the major insect pest of cotton, Heliothis armigera Hb., was found to conform to a common temporal pattern over probably some thousands of square kilometres, and other major pests, Empoasca libyca de Berg and Bemisia tabaci Gen., are considered to be similarly distributed, suggesting that their occurrence in damaging numbers may be dominated by transport and concentration by major windfields rather than by natality and mortality within a field or area. This posibility was investigated using a Pilatus Turbo-Porter aircraft fitted with Doppler Navigator equipment and an insect collecting net, and densities of flying insects monitored by a ground-based Marine-type Radar.

The results of this study will make it possible to determine the spatial extent of a threatening population and the time during which that population is present, so that control action may be taken on a commensurate scale. Such matching of scale of operations to insect mobility is of particular importance when repeated invasions occur during periods of rapid crop growth, because it enables non-persistent insecticides to be employed, thus providing potentially better utilisation of parasites and predators than can be achieved by maintaining the crop as an environment lethal to insects. These procedures, connoted ‘synoptic survey’ and ‘synchronous control’, require that the control is applied on a scale determined by pest mobility rather than by the boundaries of fields or other artificial constraints. Evidence is accumulating regarding the importance of insect mobility, in particular adaptive dispersal, in population dynamics and this may require re-assessment of farmer and government responsibilities in crop protection.  相似文献   

5.
Abstract

The Agricultural Research Service of the USDA has been actively engaged in research on the biological control of aquatic weeds since 1959. Research emphasis until 1967 was on alligatorweed, Alternanthera philoxeroides (Mart.) Griseb. As a result of this research, three species of insects from Argentina were released in the southeastern United States. Alligatorweed control with these natural enemies has been variable; but indications are that control will be substantial over most of the range of the weed.

One species of weevil, Neochetina eichhorniae Warner, has been released against water hyacinth, Eichhornia crassipes (Mart.) Solms, in the USA as a result of research in Argentina. A second closely related species, N. bruchi Hustache, is presently undergoing final clearance procedures. Several other arthropods are being studied in Argentina as possible biological control agents of water hyacinth.

A USA sponsored programme in Yugoslavia under the direction of Dr M Leki? resulted in the discovery of two insect species that show potential as control agents for eurasian watermilfoil, Myriophyllum spicatum L. Further testing for host specificity of these insects will be carried out in the USA in quarantine in Florida.

A USA sponsored Pakistan programme under Dr M. A. Ghani is investigating insects and other phytophagous organisms attacking Hydrilla verticillata Royle. The results are encouraging. PANS 20: 444–450, 1974.  相似文献   

6.
In recent years, several species of alien scale insects have arrived and spread rapidly through European and Mediterranean countries. One hundred and twenty‐nine species of alien scale insects have so far been recorded in Europe. This paper presents a list of alien scale insect species for Croatia, comprising 56 species from 8 different families. Four of them are new records for Croatia: Aonidiella taxus Leonardi, 1906, Ichnaspis longirostris (Signoret, 1882), Phoenicococcus marlatii (Cockerell, 1899) and Spilococcus mammillariae (Bouche, 1844). The majority of species recorded belong to the following families: Diaspididae (28 species), Coccidae (12 species), Pseudococcidae (10 species), Eriococcidae (two species). The scale insect families Dactylopidae, Margarodidae, Ortheziidae and Pheniococcidae comprised only one recorded alien species each. During the time frame covered in the review (from the beginning of the 20th century until 2015), the majority of alien scale insect species (23) were registered in the period from 2000 to 2015. Data on the origin of introduced alien scale insects shows that the majority of the species originate from Asia (22 species), followed by North America (6 species), Africa, Australia and Central America (5 species each) and South America (4 species), with 9 species being of unknown origin.  相似文献   

7.
Abstract

Water hyacinth is the most serious aquatic weed in India, infesting more than 200000 ha of water surface. Successful biological control of this weed was achieved in a fully infested tank covering 20 ha at Bangalore. More than 95% of the infestation was cleared within 32 months by releases of Neochetina eichhorniae Warner. The insect also spread along a water channel and controlled water hyacinth infesting a nearby tank. Drying up of the tank after the insect population had spread throughout and increased to 3.1 adults/plant hastened weed control. Fresh plants emerging after rains were suppressed by the residual population of insects. N. eichhorniae along with N. bruchi Hustache is being supplied to centres throughout the country for multiplication and releases. Sustained efforts with these insects holds out promise of control of water hyacinth in India.  相似文献   

8.
为明确东亚迁飞场重要通道—雷州半岛空中昆虫的群落结构特征,于2022年在雷州半岛设立探照灯对夜间昆虫进行诱集及种群动态监测,并采用Margalef丰富度指数、Shannon-Wiener多样性指数和Pielou均匀度指数分析物种多样性。结果表明,诱集昆虫隶属于12目61科126属146种,其中鳞翅目、鞘翅目和半翅目昆虫是诱集量和物种丰富度最多的3大类群,分别占所有诱集昆虫总数的72.37%、11.18%和6.58%。诱集昆虫不仅包括草地贪夜蛾Spodoptera frugiperda、劳氏黏虫Leucania loreyi和斜纹夜蛾S. litura等多种重要的迁飞性害虫,还包括中华草蛉Chrysoperla nipponensis、黄蜻Pantala flavescens和异色瓢虫Harmonia axyridis等迁飞性天敌昆虫。空中昆虫的诱集高峰期主要在6—9月。诱集昆虫的Margalef丰富度指数平均数为6.60,Shannon-Wiener多样性指数平均数为2.68。表明雷州半岛空中昆虫群落物种丰富度和多样性均较高,并证实许多重大农业害虫在迁飞过程中途经雷州半岛。  相似文献   

9.
采用生物活性追踪法,从苦楝根皮、树皮和果实中分离出多种四环三萜类杀虫有效成分。这些成分对菜青虫和亚洲玉米螟均表现出明显的拒食活性,川楝素对菜肯虫还有明显的胃毒活性。从苦楝中分离出的几种非四环三萜类物质对昆虫的生物活性均较低,仅表现出一定的拒食活性。另外对几种三萜衍生物的生物活性进行了测定与比较。  相似文献   

10.

BACKGROUND

The public's negative attitudes towards household insects drive tolerance for these insects and their control. Tolerance levels are important in integrated pest management (IPM), as are pest knowledge and information. The risk information seeking and processing (RISP) model describes the relationships between personal factors and information‐seeking behaviour. We combined IPM and RISP to determine important relationships between factors driving insect tolerance levels and information‐seeking behaviour through an online survey and tested whether this model is valid and generally applicable.

RESULTS

Relationships between variables from both IPM and RISP models were tested for seven insect species. Tolerance levels were measured with two factors: willingness to pay for pest control and whether insects are tolerated. Willingness to pay for control was positively affected by age, experience, risk perception, insect characteristics, and negative emotions and affected behavioural intention, by influencing information sufficiency and information‐seeking behaviour. Tolerability was influenced by perception of insect characteristics and determines whether control measures are taken.

CONCLUSION

It was possible to combine the RISP and IPM models. Relevant driving factors were a person's age, experience, risk perception, negative affective responses, tolerance levels, relevant channel beliefs about online forums, information sufficiency and information‐seeking behaviour. There was, however, variation in important factors between different insects. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

11.
Abstract

In an insect pests survey of soybean during 1977–1980, in the rabi and kharif seasons, 14 species were more, and 33 species less abundant, representing 19 families under seven orders. The occurrence of Aphis spp., Atractomorpha spp., Spilosoma obliqua W., Monolepta signata Olv., Nezara viridula L., Myllocerus spp., Riptortus spp., and Jassids were most notable.  相似文献   

12.
Studies were conducted in a flat storeroom in central Greece, filled with approx. 90 tons of wheat, in order to evaluate insect and mite species abundance, and changes in population density and distribution among sampling units and locations. The surface of the grain bulk was divided into two sampling zones: the central and the peripheral (edge). At 10-day intervals, five wheat samples were taken from the central zone and eight from the peripheral zone, with a non-partitioned grain trier (1.6-m length, 250-g capacity). Fifteen insect species and 12 mite taxa were found during the sampling period, (June 1999–Feb. 2000). The most abundant insect species wereSitophilus oryzae (L.),Cryptolestes ferrugineux (Stephens),Tribolium castaneum (Herbst) andLatheticus oryzae Waterhouse; the most abundant mite species wereAcarus siro L.,Lepidoglyphus destructor (Shrank), and the predatorsBlattisocius tarsalis (Berlese) andB. keegani Fox. Grain temperature decreased during the storage period, more slowly in the central than peripheral zone; grain moisture content increased. The highest population densities for both insects and mites were recorded during September and October. The most numerous species of insects and mites showed an aggregated spatial pattern, as indicated by Iwao’s Patchiness Regression.  相似文献   

13.
Sweden requires all coniferous roundwood from countries outside Europe to have been debarked but makes no requirement for European wood. Six shipments of unbarked roundwood of Pinus pinaster from France and 14 shipments of debarked P. radiata logs from Chile were inspected in Sweden during 1988 and 1989. The imported wood from France yielded 92 insect species (90 Coleoptera and 2 Hymenoptera). Seventeen of these species do not occur in Sweden. All six consignments were thoroughly attacked by bark- and wood-boring insects, representing 25 species. The logs from Chile had been well debarked; less than 1% of the inspected logs contained living insects. Nevertheless, a total of 49 insect species (46 Coleoptera, 1 Isoptera, 1 Hymenoptera and 1 Orthoptera) were found in the 14 shipments. Of these species 21 are not indigenous to Sweden.  相似文献   

14.
A multitude of bacteria have been isolated from the guts of several insect species. Some of these have been modified to interfere with the development of the host insect or with the development and transmission of plant and animal pathogens transmitted by the host insect. We surveyed the gut flora of the Pacific Coast wireworm,Limonius canus LeConte, a serious pest of potato, at two sites in Oregon and Washington. Isolates were obtained from surface-sterilized triturated larvae by dilution plating on standard media. A rich diversity of species was found in 86 isolates, including spore-formers, non-spore-formers and aerobic and facultatively anaerobic species collected on four sampling dates at each location. Twenty-one of the isolates were identified to species based on rDNA sequence (nine distinct species). An additional 34 isolates were identified to genus from the sequence data while six isolates could be assigned only to family based on sequence comparisons. Twenty-seven additional isolates were identified to species (9), genus (17) or family (1) based on side-by-side morphological comparisons with isolates identified from rDNA sequence. The most frequently isolated bacterium wasBacillus megaterium, followed byRahnella aquatilis. A naturally occurring bacterium found in the gut and/or environment of a targeted insect that is modified to express toxins or other detrimental substances could provide certain advantages (such as persistence and recycling) over inundatively applied microbial control agents, particularly within soil habitats. The hypothesis that these species or others from the survey represent candidates for genetic modification to provide control options forL. canus is discussed.  相似文献   

15.
The commercially available trap WB Probe II Trap have been used in laboratory to monitor insects activity in grains at 24±1°C and 70±5% r.h.. The major coleopteran pests of cereals in Italy,Oryzaephilus surinamensis (L.),Rhyzopertha dominica (F.),Sitophilus oryzae (L.) andTribolium castaneum (Herbst), were added to the grain at about 0.9 insect per kg. Two tests were prepared: in the testA insect activity was observed in spring wheatTriticum aestivum, L.; in the testB were compared in oat grainAvena sativa L., spring wheatTriticum aestivum L. and maize grainZea mays L. Significant differences in the numbers of insects collected by the traps were observed, both when compared across traps and cereal types. In all cereals considered traps trapped moreS. oryzae thanT. castaneum andO. surinamenis; the species less trapped wereR. dominica.  相似文献   

16.
Hawthorn (Crataegus monogyna) is one of the natural hosts of Cacopsylla melanoneura, the acknowledged vector of ‘Candidatus Phytoplasma mali’, the causal agent of Apple Proliferation disease, a serious and growing problem for apple production in Europe, particularly in northern Italy. Wild plants could be important sources of both insects and phytoplasmas, but their role in the epidemiology of phytoplasma diseases and their insect vectors has never been thoroughly examined. Cacopsylla melanoneura’s primary host is hawthorn, a plant closely related to apple which often grows wild near orchards. Other psyllid species feed on hawthorn, but no data are available on their possible role as phytoplasma vectors. We investigated the hawthorn’s psyllid fauna in northwestern Italy using yellow sticky traps, beat trays, and molecular analyses from 2003–2005, to study the relationship between hawthorn, the phytoplasma and the insect vector. Population dynamics were monitored, and insects and hawthorn samples were analysed by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and DNA sequencing for the presence of phytoplasmas. Cacopsylla melanoneura was the dominant psyllid species, followed by C. peregrina, C. affinis and C. crataegi. PCR and RFLP analyses revealed the presence of different fruit tree phytoplasmas in hawthorn plants, and in all four psyllid species.  相似文献   

17.
Within entomophagous insects, hymenopterous parasitoids are important regulators of natural populations of insects including pests. Pesticide treatments are largely used in orchards for economic reasons. These treatments allow for greater productivity, but they may also impact upon non-target insect populations. Drosophila and their hymenopterous parasitoids are abundant in orchards and are not direct targets of pesticide treatments. In this work, natural populations of Drosophila and their parasitoids were monitored from June to November, and their abundance was reported from two types of orchards. One type was under conventional pesticide treatments, mostly fungicides (“Treated plot”), and the other was under low-input treatments (“Low-input plot”). Five Drosophila species and five parasitoid species were present in both types of orchards. A time effect on abundance was found with two peaks of abundance, one in August and the other in autumn (October), corresponding to a fluctuation of numbers depending on the availability of resources. When comparing insect abundance between the two types of plots, the abundance in the Treated plot was found to be lower than or equal to that in the Low-input plot. Furthermore, a significant decrease in the abundance of two scarce parasitoid species (Leptopilina heterotoma and Asobara tabida) that could lead to their disappearance was also observed. The results are discussed in the context of the diverse lethal and sub-lethal effects of pesticides on the development and reproduction of natural populations of insects and their importance as natural enemies.  相似文献   

18.

Studies were conducted in northern Ghana in 1996 and 1997 to assess any changes in the quality of insects in different generations of the millet stem borer, Coniesta ignefusalis (Hampson), over the growing season. The goal was to determine if, and to what extent, such changes are responsible for observed differences in the sizes of populations of successive generations of the insect. Pupae from diapause larvae gave rise to adults that were significantly smaller and had lower reproductive rates than those derived from non-diapause larvae. There were, however, no significant differences between the non-diapause generations for all the quality indicators studied. The results suggest that observed differences in the sizes of generations developing fromnon-diapause anddiapause larvae of C. ignefusalis are, at least, partly due to differences in the inherent quality of individuals of these generations.  相似文献   

19.
Abstract

Weeds are major components of agro-ecosystems and they affect the biology of pests and beneficial insects in several ways; provision of flowers, presence of neutral insects, modification of crop microclimate, production of chemical stimulus, alteration of colonisation background, etc. The more relevant beneficial crop–weed–insect interactions are discussed. The role of weeds in regulating pest populations is illustrated by studies on bean (Phaseolus vulgaris L.) cropping systems, in which chemical interactions between Empoasca kraemeri Ross &; Moore and two grass weeds were identified. It is proposed to continue and develop this kind of research in order to incorporate weeds into pest control strategies.  相似文献   

20.
Abstract

Melanaspis glomerate (Green) is a serious pest of sugarcane in India and does not have effective natural enemies. Parasites of M. smilacis Comst. and M. paulislus Hempel from Brazil and Aphytis mytilaspidis (Le Baron) collected from Aulacaspis tegalensis (Zehnt.) in Mauritius were imported for biological control trials. Only Neococcidencyrtus sp., an endoparasite of M. paulistus accepted M. glomerata. Among the coccinellid predators that were imported only Chilocorus cacti (L.) bred on M. glomerata. The non‐acceptance of this scale insect by most of the introduced natural enemies seems to indicate the need for confirmatory studies on its taxonomic status. Until such time as this is done and suitable natural enemies are found, an integrated approach for its control may have to be considered.  相似文献   

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