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Unmanaged, or feral, honey bees can be abundant in Australian agricultural landscapes and provide substantial, but unquantified, crop pollination services. This makes these production syste...

The ladybird beetles form the tribe Scymnini are important group of beneficial insects, and they mostly feed on aphids, mealybugs, scale insects, whiteflies and mites. Five species from the...

Late and early maturing potato cultivars were grown under two organic management systems using straw mulch or mechanical cultivation for weed management. It was found that application of straw mulch at emergence consistently increased total and marketable A-size yields for the late season cultivar Freedom Russet, and shifted the profile of marketable A-size tubers toward larger sizes. Increased yields were seen for the early season cultivar Dark Red Norland in some years, and may be related to amelioration of environmental stress by straw mulch. Mulch provided more effective control than mechanical cultivation for some broadleaf weeds, especially late in the season as potato foliage senesced and weed numbers tended to increase in unmulched plots relative to mulched plots. Grass weed incidence did not differ between straw mulched and mechanically weeded plots. Mulch did not consistently impact abundance of pest, virus vector, or predatory insects, although potato leafhopper numbers tended to be lower in straw mulched plots than mechanically cultivated plots. Straw mulching did not impact PVY incidence. It was concluded that straw mulching is a viable management option for organic potato production, with potential benefits for broadleaf weed management and tuber yield.

The commercial adoption of transgenic Bacillus thuringiensis (Bt) cotton (Bollgard II®) reduced the use of insecticides to control Helicoverpa spp. However, the ineffectiveness of the Bt toxin against sucking pests such as silverleaf whiteflies (Bemisia tabaci) resulted in a marked increase in B. tabaci populations and in the use of insecticides to control this pest. The effect of the entomopathogenic fungus Aspergillus sp. BC 639 on B. tabaci and beneficial insects (predominantly predatory insects) was studied in commercial cotton field trials. The results showed that oil-based extracts of the entomopathogenic fungus BC 639 control the number of B. tabaci adults and nymphs in commercial transgenic cotton crops. The BC 639 fungus caused 60.0%, 67.2%, and 68.8% mortality in adults, and 54.6%, 62.3%, and 51.7% in nymphs at 7, 14, and 21 days after treatment, respectively, relative to the unsprayed controls. The effect of BC 639 at concentrations of 125, 250, and 500 ml/ha on low-density B. tabaci (∼...

Cotton crop Ethiopia is a high-value crop and the strategy for pest control is insecticide-dependent with no consideration of beneficial insects. We carried out a study in 2013 and 2014 to determine the effectiveness of a food spray product developed with local ingredients from Benin (BFP), a food spray product developed from Ethiopian ingredients (EFP), and mixtures of the individual food spray products with and without neem extracts. Applications of BFP and of EFP alone attracted and retained beneficial insects and significantly reduced the number of pests, and increased cotton yields and profitability. The net margins of 18,418 and 18,642 Ethiopian birr (ETB)/ha were achieved from the plots treated with BFP and EFP, respectively, and 13,000 ETB (US$1 = 19 ETB) was achieved from the unsprayed plots. Addition of neem extract to the food spray products decreased the number of beneficial insects attracted to the food spray plots. In conclusion, food sprays can be used as part of integrated pest man...

The large carpenter bees are very promising pollinators for many agriculture crops. The nesting biology and some foraging activities of these large carpenter bees are documented from the north-western Pakistan, most extent of its natural distribution, as these species are potentially important pollinators of cucurbit crops and some agriculture crops in the region. Nests of the large carpenter bees, Xylocopa pubescens Spinola, 1838 and Xylocopa fenestrata Fabricius, 1798, around the Ismaila village, Swabi, Khyber Pakhtunkhwa Province, Pakistan, were observed and sampled from June to August 2012 and 2013. Nest details were recorded and foraging times on various floral species were documented, with bees preferentially nesting in dead wooden stems of Poplar (Populus deltoides) and Sesbania (Sesbania bispinosa). The dissection of nests was carried out and both nest architecture and nesting biology of the species were described. The importance of such studies on wild bees in Pakistan is important for th...

Lepidopterans play an important role in human economy, since some of them are harmful to vegetation in agriculture and some others produce useful materials such as silks, etc. To recognize lepidopt...

Aphids and whiteflies are significant direct pests of squash and transmit plant viruses. The use of buckwheat, Fagopyrum esculentum Moench, as a living mulch intercropped with squash has been shown to reduce insect pests and diseases while increasing the abundance of beneficial insects; however, how to best implement buckwheat in squash fields has not been determined. Several arrangements of intercropping buckwheat and squash were evaluated, with and without the introduction of a natural enemy, Delphastus catalinae (Horn), to find a tactic that reduces insect pests and disease incidence while increasing marketable yield. Intercropping treatments included planting strips of buckwheat alternating on either side of the squash with and without D. catalinae (arrangement A), planting buckwheat in the middle of squash planted on both sides of the bed with and without D. catalinae (arrangement B), buckwheat planted on both sides of squash (arrangement C), and a bare ground treatment. Aphid densities and i...

Prey capture and food scavenging activities of Oecophylla longinoda were monitored through regular weekly samplings during two consecutive years (2009-2010) in a large mango orchard of the Borgou department of Benin, West Africa, a main mango production area located in the Sudan agro-ecological zone. In both years, interspecific competition with other ants occurred mainly during the dry season (January-March) resulting in increased captures of Formicinae, Myrmicinae and Ponerinae. More prey was caught during the rainy season (end April to end October) than during the rest of the year, with Diptera and Coleoptera prey peaking in May and June, respectively, along with the mango season. As insect prey quickly decreased during November-December weaver ants increasingly collected seeds and plant debris. A total of 241 species of insects were captured including 61 species (25.3%) associated with mango and a few with cashew, among which 48 mango pest species (78.7% of species associated with mango tree). Only five species (2.1%) of beneficial insects were captured. It is concluded that the presence of O. longinoda colonies is beneficial to perennial tree cropping systems such as mango and cashew.

Homogenization of agricultural landscapes affects ecological processes and biodiversity and can affect the community composition of ecosystem service providers. These effects can have particular impact in landscapes dominated by monocultures of pollinator-dependent tree crop plantations, which create both spatial and temporal homogeneity at the landscape scale. I looked for associations between the proportion of nearby unmanaged vegetation and potential wild pollinator groups collected within flowering almond orchards in two types of landscape. In the Complex landscape, characterized by a heterogeneous mosaic of multiple crops, semi-natural grassland and natural woodland, insect pollinator groups were not associated with unmanaged vegetation. In the Simple landscape, dominated by monoculture almond plantations, most pollinator groups showed positive relationships with the two unmanaged vegetation types (grassland and woodland). In particular, all wild bee and all but one hoverfly individual were found in ...

Bee-keeping is a potent low investment enterprise in JK weak research and development; insufficient support for small beekeepers are the main constraints in promoting migratory beekeeping in th...

Parasitic wasps are one of the most abundant natural enemies of insect pests and the most ecologically understudied. Agathirsia is a genus of solitary, parasitic wasps, restricted to arid regions of the south-western United States of America and Mexico. They often parasitise the larvae of lepidopteran (butterflies and moths) crop pests. Pollen analyses were conducted on 127 specimens of 19 Agathirsia species to determine possible food sources and plant taxa important to these beneficial insects. Pollen was examined with both light microscopy (LM) and scanning electron microscopy (SEM). Pollen was removed from the head more than any other insect part (96% of the time). In the LM analyses, nearly 1700 pollen grains were recorded and assigned to 117 pollen types, 49% of which were Asteraceae. For the SEM analyses, pollen was identified but not counted. Eighty-eight pollen types were identified, of which 48% were Asteraceae. Pollen from 36 families, 65 genera and nine species were identified. Asterac...

The aim of this study was to investigate farmers’ knowledge of integrated pest management (IPM) and learning style preferences. The study population comprised farmers in Hossein-Abad town, in the city of Karaj, Iran. A sample of 200 farmers was divided into two groups of 100 individuals according to gender. A questionnaire was used to obtain information on demographic characteristics of respondents, knowledge of IPM, and learning style preferences. Farmers’ knowledge of IPM was assessed by the average of four attributes including negative aspects of pesticide use, awareness of alternatives for controlling pests, knowledge of beneficial insects, and IPM definition. IPM knowledge mean scores of male and female farmers were 5.84 and 5.43, respectively. Males were more familiar with alternatives for controlling pests than their female counterparts. Females were more familiar with the negative aspects of pesticide use. Sixty-four percent of males had unimodal preferences compared to 49% of females. In contrast...

The development and adoption of transgenic (Bt) crops that express the Bacillus thuringiensis (Bt) toxin has reduced the use of synthetic insecticide on transgenic crops to target Helicoverpa spp., the major insect pest of cotton in Australia. However, it has also increased the threat posed by sucking pests, particularly Creontiades dilutus (green mirid), which are unaffected by the Bt toxins in transgenic cotton crops. Here we report the efficacy of the entomopathogenic fungus Aspergillus sp. (BC 639) in controlling the infestation of transgenic cotton crops by C. dilutus and promoting interactions of transgenic cotton with beneficial insects. The results showed that the number of C. dilutus adults and nymphs recorded on plots treated with 1000, 750, 500, 250 ml/ha BC 639 fungus formulation were the same as on plots treated with the recommended concentration of the commercial insecticide Fipronil. The fungus was found to have minimal effect on predatory insects compared with Fipronil and was mos...

Organic cotton is considered a high-value crop in Benin, West Africa, but problems of high costs and reduced yield arising from the lack of effective pest control have left cotton farmers with low profit margins. We have developed a novel supplementary food spray product (Benin Food Product, BFP) to attract and retain beneficial insects on these crops to improve the management of pests. Applications of BFP to organic cotton, with and without other biological control agents, attracted and increased the densities of predatory insects, significantly reducing pest insect numbers and producing higher yields than in cotton treated with neem extract or in cotton that was untreated. In economic terms, the average gross profit margin on the BFP-treated plot was 125,340 FCFA (French Communaute Financiere Africaine; USA $1 = 483 FCFA) with 80,248, 89,450 and 968 FCFA on plots treated with neem extract, synthetic insecticides, and no control agent, respectively. These results clearly show that a supplementary food sp...

Three species of chalcidoid parasitoids of scale insects are recorded for the first time in Brazil: Adelencyrtus moderatus, Homalopoda sp., and Diglyphomorpha sp.; and new parasitoid–host associations are recorded between the chalcidoids Encarsia lounsburyi with Hemiberlesia palmae, Encarsia lounsburyi with Melanaspis smilacis, and Diglyphomorpha sp. with Dysmicoccus brevipes.

Water deficit, a common constraint in forestry, is the main cause of plant stress during plantation. The survival and growth of seedlings is also compromised by herbivory during establishment. The potential of nursery preconditioning to enhance survival chances of future trees by reducing palatability or attracting beneficial insects as a result of changes in chemical defences may be an answer to overcome this situation. Changes in essential oil production and composition were evaluated by GC and GC-MS in Eucalytus camaldulensis seedlings submitted to drought during four weeks at the last stage of nursery period (20 weeks). Significant changes in essential oil relative composition were found. Seedlings (young leaves) submitted to drought developed a terpenoid blend, which has been previously associated to mature leaves and related to their higher resistance towards herbivory. Total amount of non-oxygenated terpenes decreased by 44%, whereas some oxygenated sesquiterpenes (globulol, epiglobulol an...

Seasonal adaptations of insects to climate conditions are always a combination of their responses to a great variety of environmental stimuli. Our investigations deal with some aspects of the long-term emergence period in phytophagous as well as entomophagous insects in Lithuania. During the investigation carried out in Lithuania from 1982 to 2004 the emergence season of adult Pleuroptya ruralis and its primary parasitoid Macrocentrus grandii was recorded between June and August. The beginning of adult emergence of P. ruralis has a negative correlation with spring temperature. The peak of P. ruralis adult emergence and values of the M. grandii adult emergence period have a negative correlation with June temperature. A tendency for an earlier peak emergence period has been recorded. It may be linked with a rise in annual, spring and summer temperatures in Lithuania.

Commonly used pesticides and handling practices which might expose farmers and their environment to chemical hazards were investigated in the Irepodun/Ifelodun local government area of Ekiti State,...

SummaryAvocado (Persea americana Mill.) flowers, with their synchronously dichogamous behaviour, are considered to be pollinated by honeybees, despite the lack of any direct evidence. Results in southern Florida showed that avocado pollen was transferable by wind, and was dispersed over a brief period of time (15 – 60 min) each day. Ten ‘Hass’ avocado orchards in the Santa Clara River Valley, CA, USA, planted far from any known ‘Zutano’ polliniser trees, were selected to investigate the impact of honeybees on pollen transfer. ‘Zutano’ pollen (5 g per insert) was placed at the entry to beehives (approx. eight beehives per orchard) and refreshed four-to-five times during the flowering season. Successful pollinations were determined by parental analysis of harvested ‘Hass’ fruit from trees located at various distances from the beehives, and at three different stages of fruit development, using microsatellite DNA markers. The results showed no significant difference in the proportions of ‘Zutano’-pollinated f...

Experiments were conducted to determine factors that could influence seed production in the potential biofuel seed crop, Jatropha curcas. Controlled pollination experiments in a South African plant...

The spinosad bait spray GF-120 Naturalyte F® (Dow AgroSciences LLC, Indianapolis, IN, USA) is widely used in commercial olives in California. Because of concern about its non-target effects on beneficial insects, we studied its impact on feeding behavior, mortality, and reproductive parameters of adult green lacewings, Chrysoperla carnea (Stephens), under laboratory conditions. Male and female feeding rate and quantity, and subsequent mortality, were compared over a 5-day period following a 24-h exposure to honey, GF-120, or the bait component (without spinosad) in two-choice and no-choice assays. All treatments were ingested equally when offered alone. Spinosad did not impart repellency or preference to GF-120 relative to the bait. Honey was preferred in choice tests with GF-120 or bait. Significant mortality occurred when GF-120 was offered alone, but was not significant when it was offered in choice with honey or bait. In a separate assay of female longevity and reproduction, mortality rate as...

Summary Following the identification of a biologically-active compound from the sex pheromone gland of the autumn gum moth, Mnesampela privata (Guenee) (Lepidoptera: Geometridae), field studies were conducted to compare the potential efficacy of pheromone traps with light traps and to determine whether pheromone trap catches could forecast the future abundance of eggs and subsequent defoliation. Small to incipient populations of the adult moth were monitored over two moth flight seasons using pheromone traps in 12 plantations of either Eucalyptus globulus Labill. or E. nitens (Deane and Maiden) Maiden in Tasmania, Australia. In three of these plantations, light traps were also used to monitor adult moth numbers for one moth flight season. Pheromone trap catches from Tasmania were compared with those in a plantation of E. grandis W.Hill ex Maiden in Victoria where an outbreak of M. privata was ongoing. Early in the season (February—April), light traps caught five to six times more M. privata than pheromone...

Engineering data for improving the design of applicators for beneficial insect's eggs and facilitating egg cleaning at mass-rearing plants are presented. A vertical air column was developed to measure terminal speed of beneficial insect eggs. Raw material was sorted into fractions according to terminal speed and photos were taken for measuring dimensions of particles. Particle distribution was evaluated for two beneficial insect eggs used in biological control (Chrysoperla rufilabris and Ephestia kuehniella eggs parasitized by Trichogramma brassicae) and for one unparasitized host eggs (E. kuehniella). Density measurements were performed as these data were required for calculating terminal speeds using the theory of free falling bodies. Unparasitized E. kuehniella and C. rufilabris eggs stored at 5°C showed constant terminal speed (1.9 and 1.34 m/s, respectively) and density (1.05 g/cm3, for both). Terminal speed of parasitized E. kuehniella eggs decreased from 1.32 to 1.06 m/s with increasing st...

Knowledge of flight movement is crucial to an understanding of the ecology, behaviour, genetics and evolutionary success of most insect species. However, all but the shortest flights will frequently take the insect beyond the range of both human vision and many opto-electronic devices, and thus radar technology has a valuable role to play in several distinct areas of movement research. In this review, we firstly consider the monitoring of high-altitude windborne movements of insect natural enemies, with emphasis on how novel vertical-looking radars are being employed to observe the migrations of aphid predators in the UK. Secondly, we discuss how scanning radars, with and without harmonic tags, have increased our understanding of the foraging flights of beneficial pollinators (bees), and how this technique might be applied to natural enemies. Lastly, we outline the use of harmonic direction-finders in studying the pedestrian and short flight movements of various beneficial insects, including predators. In...

For beneficial insects--predators and parasitoids--to be used effectively within pest control scenarios, it is often necessary to have fundamental as well as more applied information about them, including data on population dynamics, host switching and breeding systems. In recent years, such information has been gained by the use of molecular DNA markers. In this article, we briefly discuss the range of molecular markers available and their potential uses, concentrating on how particular markers have been employed to unravel different patterns of behaviour. Whilst alternative methods of tracking insects have proved highly informative when applied over small geographical scales (e.g., fluorescent dyes and radar transponders as attached to bees, etc), these approaches tend to be confined to studies of movement rather than other potentially important behaviours.

Visual observation enables a good understanding of beneficial insect behaviour within a locality, but once the rapidly dispersing beneficial insects walk or fly, they are soon lost from view. The harmonic radar tracking system developed to follow Colorado potato beetles, Leptinotarsa decemlineata (Say) in flight is proposed as a useful technique to increase the study range of beneficial insects from that of the plant to that of the landscape. These insects belong to a wide array of orders and families and many are small in size. Nevertheless, we estimated that some 15% of beneficial insects are at least similar in length to the chrysomelid beetle for which the feasibility of using a portable harmonic radar has been successfully demonstrated. As for the Colorado beetle, the pulsed radar transmitter, the tag, the antenna gain and the receiver of the portable radar system must be carefully designed to provide both a sufficient tracking range and a sufficient beam width. The construction of the tag is strongl...

A multi-use device was developed for the collection, short-term storage, transport, and delivery of Ophraella communa (Coleoptera: Chrysomelidae), a biological control agent of common ragweed, Ambrosia artemisiifolia. The device is made from a 125-ml plastic specimen container that can hold O. communa adults or pupae. When used as an aspirator, insect collection and counting times are reduced. O. communa adults and pupae can be stored inside the container at 3°C with median survival of 41 and 21 days, respectively. A cotton wick saturated with water or a 5% sugar solution nourishes insects during transport and the container design minimizes insect mortality by providing an optimum microclimate during insect storage and transport. Designed to protect insects from rainfall and to limit encounters with predators and parasites, the containers can be used for field releases of O. communa adults and pupae. Although the container has been designed and tested for O. communa, it is highly versatile and could possi...

Recent increases in the global area planted in GM crops have been accompanied by rising public awareness of agricultural practices and concern about the environment. Honey bees are widely recognized as important beneficial insects. In most countries, regulators assessing potential risks and benefits from GM plants list the honey bee among the ‘non-target’ species that need to be considered before these plants are released. Research on honey bees and GM crops has focused on the presence of GM material in honey, the roles that bees may play in the flow of genes from GM crops, and the potential impacts of GM plants on bee health. This article summarizes research on bee health and GM. There is now a considerable body of knowledge on this topic and some well-established techniques for assessing risks to bees before new plants are released.

Summary The longevities of two species of native wasp parasitoid (Heteropelma scaposum (Morley) and Habronyx pammi (Gauld)) given floral nectar and honeydew from scale insects are compared. These parasitoids kill autumn gum moth (Mnesampela privata (Guenee)) which can outbreak in eucalypt plantations and cause considerable defoliation. The longevities of male He. scaposum given access to flowering Alyssum maritimum and Aster ‘Easter Daisy’ (both exotics) were no different from those of starved wasps. Hence, inter-row sowings of these plants in plantations on ex-pasture sites are unlikely to benefit these parasitoids. Compared to starved individuals, males of both species usually lived longer when given access to Eucalyptus globulus subsp. globulus leaves. Leaves from the previous season enabled male He. scaposum to live longer than did current season's leaves. The inference that it was honeydew on the surfaces of E. globulus subsp. globulus leaves that increased the longevities of both species of wasp was...

This study discusses the farmers' pest management practices and their perception about the impact of pesticide on the environment. Fieldwork was carried out in Higashi Hiroshima City of Hiroshima prefecture. The data were collected from the rice farmers through questionnaire survey. Findings revealed that the farmers used a wide variety of pesticides. Among the pesticides used by the farmers, insecticides are environmentally more hazardous than the herbicides and fungicides. Farmers have good knowledge on technical aspects of the pesticide but this is not reflected at the cognitive level. They showed moderately favorable attitudes about the risk of pesticide usage. Farmers' perception level of the impact of pesticide use on the environmental item assessed was moderate. Food safety, applicator's health, food quality and wildlife tended to generate the highest levels of perception while air pollution and beneficial insects yielded the lowest level of perception. Farmers' age has a positive and sign...

Research was conducted in a certified organic apple (Malus x domestica Borkh.) orchard in 2000 to determine the effect of organic pest management techniques on pest control, apple yields and microbial populations on harvested apples. In Experiment 1, apple colouring bags, sticky red spheres, kaolin particle film, kaolin particle film plus sticky red spheres, or colouring bags plus sticky red spheres were applied to Redfree, Jonafree and Liberty apple trees in a split-plot design. Insects and diseases were sampled in the control and kaolin particle film treatments. Apple yields and insect damage ratings at harvest were determined for all treatments. There was a significant treatment x cultivar interaction related to insect damage on apples. Insect and disease damage ratings throughout the growing season and at harvest were lowest in Jonafree trees treated with kaolin particle film or colouring bags. There was no effect of treatment on beneficial insects during the growing season. Marketability was...

A pilot study performed on the Pacific coastal plain of Chiapas, Mexico, focused on the prevalence of maize crop infestation by insect pests, parasitism of pests and the abundance of insect predators in maize plots with weeds compared with plots under a regime of rigorous manual weed control. Sampling was conducted on four occasions at 20, 32, 44 and 56 days post-planting. Infestation of maize by fall armyworm larvae, Spodoptera frugiperda (Lepidoptera: Noctuidae), was more than twice as great in plots with strict weed control compared with weedy plots at 20 days post-planting, but declined thereafter in both treatments. The prevalence of aphid infestation and the abundance of nitidulid beetles were consistently greater in weed-controlled plots. In contrast, the density of beneficial predatory Coleoptera increased significantly in plots with weeds, and it is suggested that this probably explains the lower incidence of pests. S. frugiperda egg masses placed in experimental plots suffered a significantly higher incidence rate of parasitism by Chelonus insularis (Hymenoptera: Braconidae) in clean plots (42.0%) compared with those placed in weedy plots (3.75%); it is suspected that weeds may hinder the location of egg masses by parasitoids. Overall, the presence or absence of weeds had a marked influence on the arthropod community present in maize fields. The weeds did not affect maize plant height, the levels of plant damage or the yield of grain from plants under each type of weed regime, implying that competitive effects of weeds may be offset by greater numbers of beneficial insects in weedy plots. Our pilot study indicates that strict weed control in maize may be unnecessary.

Short-term storage of second and third instars of the coccinellid Coleomegilla maculata lengi Timberlake can be achieved efficiently through utilization of temperatures below its thermal threshold of development. Survival, voracity and preimaginal development time were evaluated for larvae kept at 4 and 8°C for up to 5 weeks. Survival was close to 100% for the first two weeks of storage, but decreased drastically afterward and was 0% after 5 weeks. Storage at low temperatures did not diminish the voracity of larvae after storage. Development completely stopped during cold storage but resumed without significant effect after larvae were returned to 24°C. This study indicates for the first time that cold storage of C. maculata second and third instars is possible for a period of up to 2 weeks and provides a technique that could benefit biological control programs by increasing availability of beneficial insects.

The major constraint to the production of good quality cabbage in Papua New Guinea (PNG) is posed by a complex of insect pests which includes the Diamondback Moth Plutella xylostella (L.) as the most prominent species. In order to evaluate the prospects of a classical control approach economically important major pests and their natural enemies were surveyed in three cabbage growing areas with distinct climatic regimes at low-, mid- and high-elevation. In the PNG highlands (Goroka and Tambul area, Western Highlands Province) the release and successful establishment of the P. xylostella -specific parasitoid Diadegma semiclausum (Hellen) reduced crop losses remarkably since 1995. Favourable circumstances, such as continuous brassica cultivation and low status of associated lepidopteran pests, particularly at Tambul (2400 m above sea level) with an almost temperate climate, were supportive for this approach. In the arid PNG lowlands (Laloki area, Central Province) the introduced P.xylostella -parasitoid Cote...

Details of the biology of the braconid subfamily Sigalphinae, based on rearings of Acampsis alternipes (Nees), are provided for the first time. A. alternipes is a solitary, koinobiont larval endoparasitoid of the geometrid moth Alsophila Hubner, though there is an external feeding phase prior to spinning a cocoon and pupation. Two features are of potential phylogenetic significance indicating a close relationship with the subfamily Agathidinae: (1) eggs are deposited in the host's nerve ganglia, and (2) the first instar larva is polypodiform. A. alternipes completes development in the autumn and overwinters as a fully eclosed adult within its cocoon, enabling it to emerge and search for hosts early in spring. The posterior of the eclosed adult within the cocoon is immersed in a viscous liquid that also surrounds the meconium. Chemical analysis of this liquid revealed that it comprises at least 25% glycerol and a further 25% consists of various fatty acid derivatives. Oviposition and developmental stages a...

A braconid parasitoid, Diachasmimorpha tryoni (Cameron), was released from the air into Guatemalan coffee plantations that contained Mediterranean fruit flies, Ceratitis capitata (Weidemann). Parasitoid adults were chilled, placed in paper bags, and dropped from an altitude of 100 m and at an airspeed of ~ 130 km/h. Releases were made at four different densities over a period of two years. At the higher release rates parasitism levels reached as high as 84%. The feasibility of using a more technically sophisticated aerial release technique, the auger sterile-insect release machine utilized in C. capitata sterile-fly aerial eradication projects in California and Florida, was also examined. Chilled D. tryoni either alone or in combination with chilled, sterile C. capitata , were dropped over target areas and the released parasitoids examined for mortality and damage. Samples of released parasitoids were taken and tested for 'flight ability'; i.e. flight response after an opportunity to recover from chilling...

This study mainly discusses the attitude of farmers towards environment and sustainability issues of agricultural development. Field work was conducted in Nakano block of Iwami town, Shimane prefecture and data were collected from the farmers through personal interviews. Findings revealed that most of the farmers confronted low levels of environmental problems. The issues mostly confronted were the reduction of necessary aquatic life and beneficial insects in nature due to the use of agro-chemicals. Cultivation of high yielding varieties of crops with proper management practices, use of low toxicity pesticides and care in handling were the matters mostly suggested by farmers to combat environmental degradation. Most of the farmers possessed a highly favorable attitude towards the above issues. Significant positive correlation was found only between the farmers' attitude and their formal education and newspaper exposure.

A variety of plant species are being considered for the phytoremediation of selenium (Se) contaminated soils in agricultural regions of central California. Use of this plant-based technology may also attract a wide range of insects to these Se-accumulating plants. The first field study surveyed the diversity of insects attracted to tall fescue, birdsfoot trefoil, kenaf, and Indian mustard. Over 7500 specimens were collected by a sweep net collection technique for one complete growing season. Most of the 84 families identified were associated with beneficial insects, although pestiferous insects, for example, thrips, aphids, lygus, and leafhoppers, were also found. In the second study the bioaccumulation of Se in the cabbage looper [Trichoplusia ni (Hubner)] was investigated on Indian mustard grown in Se-rich water culture solution. Neonate larvae were transferred to plants and fed on Se-treated and no Se treated plants (controls) for 14 days, respectively. Pupae were collected from each treatment...

The species of the genus Orius commonly found in East African cropping systems are reviewed. Of the seven species encountered, O. albidipennis (Reuter), O. tantillus (Motschulsky) and O. thripoborus (Hesse) were the most abundant and broadly distributed. O. ugandensis is described as new, the male genitalia of O. jeanneli (Poppius) and O. naivashae (Poppius) are illustrated for the first time and O. shakebi Ghauri is a new record for Uganda. Dorsal habitus views and illustrations of the female and male genitalia are provided for each species, as well as information on distribution, habitat and host plants. Scanning electron micrographs of the metathoracic scent efferent system also are provided. A key is given to identify the economically important species of Orius in East Africa. As a result of the present study, the species O. albidipennis, O. tantillus, O. thripoborus, and O. jeanneli, are recommended as the highest priority for further studies of their potential for natural control and insect pest man...

Adoption of within-field monocultures of annual crops in modern farming systems is known to discriminate against and reduce the activity of predatory insects. In Australia, cotton fields are strictly monoculture and lack ecological diversity which could be the major cause of pest problems in the cotton agroecosystem. The utility of crops such as sunflower (Helianthus annuus), safflower (Carthamus tinctorius), sorghum (Sorghum bicolor), lucerne (Medicago sativa) and tomato (Lycopersicon esculentum) as refugia for predatory insects of Helicoverpa spp., when they were planted as strips in cotton fields, was evaluated from 1993 to 1995. Densities of beneficial insects, mainly predatory beetles, bugs and lacewings, were higher in lucerne crops than any other crop tested. In an experiment where lucerne was planted in strips within commercial cotton, the number of predators was highest in the lucerne strip and declined with increasing distance from the lucerne strip to reach their lowestlevel300 m away ...

This paper describes the use of a kytoon-supported net to sample the insect fauna flying at about 150 m above a site in West Bengal, India. The sampling took place during four periods of the year: March, May, October and November. Amongst the insects captured were some economically important rice pests (Nilaparvata lugens, Sogatella furcifera, Nephotettix spp. and Cnaphalocrocis medinalis), some of their natural enemies, and also pest aphids (e.g. Lipaphis erysimi, Aphis gossypii and Rhopalosiphum rufiabdominalis). We found thatinsectaerialdensities aloftoften remained high untillate in the night, and we deduced from this that migration over distances of tens, or even hundreds of kilometres was in progress-movements which would lead to redistribution of both pest and beneficial insects over large areas of northeast India. Differences between aerialdensities and migration rates found for the 4 months are interpreted in terms of seasonal cropping patterns and weather, and aerial densities of N. lugens, C. m...

The status of Homichloda barkeri (Jacoby) n. comb. is discussed. A key is presented to four Afrotropical Homichloda species, including fulva n. sp. The eggs, larvae and pupae of H. barkeri are described for the first time. Unusual adult and immature stage characters are discussed in relation to the placement of Homichloda in the Alticinae.

Intercropping is used to reduce pests and diseases by decreasing their establishment or performance on the crop, and by enhancing antagonist activity. The effect of intercropping cabbage with white and subterranean clover on epigeic predator activity-density was studied in two successive years in the Netherlands. The presence of clover as an intercrop resulted in significantly higher predator activity-densities and diversity, especially early during the growing season. Several carabid species, in particular Pterostichus melanarius, Agonum dorsale, and Amara similata, were affected, whereas in the staphylinids, Philonthus spp. showed a strong preference for intercropped plots. The contribution of these predators and their larvae to pest suppression and the effect of scale in determining the final result of intercropping is discussed.

From April-September 1992 and from April-August 1993, ground beetles were caught in pitfall traps in three weed strips of different ages and in the adjacent fields. The oldest weed strip contained the highest number of ground beetle species in both years. A decrease in number of species with increasing distance from the weed strips was observed in 1992. Fields bordering on two-year-old weed strips showed an increase in species diversity compared with the previous year. Within the crops, rape contained more species than wheat or maize. The extent of differences in species diversity between weed strips and adjacent fields in terms of the methodology used and the importance of weed strips for several species are discussed.

Pheromone traps together with leaf and fruit samples were used to measure the seasonal occurrence and relative pest status of three species of leafrollers (Lepidoptera: Tortricidae) in two berryfruit gardens in Hawkes Bay, New Zealand. The pheromone trap data detected slight differences in the seasonal phenology of male flights between the two properties, but reflected the relative pest status of larvae infesting leaves and fruit at only one property. Numbers of larvae of the different species found in leaves, on the other hand, were good predictors of pest status at harvest. Three species of larval parasitoids (all Hymenoptera) were reared, and their seasonal occurrence noted, but the data were inadequate to allow life‐table compilation or measurement of population regulation of their hosts.

The adult and larva of Phaedon fulvescens are redescribed and their unusual characters discussed. The potential of P. fulvescens as a biocontrol agent of Rubus is discussed.

The impact of root-feeding insects attacking the 'biennial' Carduus nutans L. in the southern part of its native European distribution was studied as part of a biological control programme against this weed for Australia. Surveys were conducted from Spain to Greece to parallel previous studies in central Europe and three populations of the weed were monitored in detail over a 2-4-year period in southern France. The damage levels and attack patterns of each insect species were recorded. The most common species damaging the roots and meristems were the weevils Hadroplontus (=Ceutorhynchus) trimaculatus F. and Trichosirocalus horridus Panzer and the syrphid fly Cheilosia corydon Harris (=grossa Fallen). In manipulative experiments, made to assess their impact on the host plant, C. corydon reduced seed production by up to 45%, while the two weevils mainly altered plant architecture. The results are discussed in relation to previous experience of using root feeders for the biological control of C. nutans.

The distribution of Rastrococcus invadens among different host plants and the impact of the mealybug on mango growth were investigated on 2067 trees in three surveys across all the ecological zones of Benin. The first survey started in 1989, less than 1 year after the first release of the exotic parasitoid Gyranusoidea tebygi. Within 3 years, G. tebygi had colonized the entire area of infestation, and was found on practically all infested mango trees as well as other infested host plants. By 1991, the incidence of R. invadens on the secondary host plants had declined significantly. The percentage of infested mango trees declined from 31.0% in 1989 to 17.5% in 1991, highest populations being found in the coastal savanna. During the same period, the mean percentage of infested mango trees having indigenous predators declined from 42.3 to 20.9%. Average mealybug densities declined steadily from 9.7 females/48 leaves in 1989, with 3.2% of all mango trees having densities above 100 mealybugs, to 6.4 females/48...