Pest control

Pest control technology, developed for temperate countries was introduced into the Caribbean without any consideration for the fragility of the islands ecosystem. A signi®cant increase in the utilization of pesticides by banana farmers in St. Lucia occurred during recent years. The mobility of two commonly used pesticides,`ametryn' [N 2-ethyl-N 4-isopropyl-6-methylthio-1,3,5-triazine-2,4-diamine] and`pirimiphos-ethyl' [O-2-diethylamino-6-methylpyrimidin-4-yl O,O-diethyl phosphothiorate] on two different soils on banana cultivated hillsides in St. Lucia was studied. Ametryn and pirimiphos-ethyl were applied to both sites, and soil samples were collected at different time intervals and were analyzed using gas chromatography. At both sites and on both soil types, quite early in the season, both pesticides leached down to 0.4 m depth. However, there appeared to be equal or greater leaching and downslope transport of pesticides on hillside 2. Pesticide concentration showed a reducing trend with respect to time and depth in both soil types at both sites. However, because of runoff interference, the half-life of pirimiphos-ethyl could not be properly de®ned, but half-life for ametryn was estimated to be 3 to 8 days. The short half-life for ametryn indicates the fast degradation of this pesticide under tropical conditions which could reduce the risk of environmental pollution. The environmental mobility of both pesticides suggests that leaching of ametryn and pirimiphos-ethyl may, in some circumstances create surface and groundwater pollution problems.

The extensive use of chemical insecticides for insect pest management has resulted in insecticide resistance now being recorded in >500 species of insects and mites. Although gut-active toxins such as those derived from Bacillus thuringiensis (Bt) have been successfully used for insect pest management, a diverse range of insectspecific insecticidal peptides remains an untapped resource for pest management efforts. These toxins act within the insect hemocoel (body cavity) and hence require a delivery system to access their target site. Here, we summarize recent developments for appropriate delivery of such intrahemocoelic insect toxins, via fusion to a second protein such as a plant lectin or a luteovirus coat protein for transcytosis across the gut epithelium, or via entomopathogenic fungi.

A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae)—a major soybean pest—was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.

Abstract}Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge. Growth and sporulation were evaluated by the total viable cell count and spore count of the preparations. Growth, sporulation and endotoxin production were affected by the sludge origin. Hydrolysed sludge gave the highest viable cell and spore counts while the liquid phase (supernatant) gave the lowest. Non-hydrolysed primary sludge from Valcartier was unable to sustain bacterial growth because of its low pH. Bioassays were conducted against larvae of spruce budworm to evaluate entomotoxic potential of the preparations obtained. In general, sludge hydrolysis increased the entomotoxicity yields. Similar entomotoxicity was observed in Black Lake secondary sludge (4100 IU/mL) as that obtained in the reference soya medium (3800 IU/mL). The use of the sludge supernatant (liquid phase) was not recommended due to the low entomotoxic potential obtained. #

After the spraying of insecticides against cockroaches in a kindergarten insecticide residues were detected over several months in spite of extensive decontamination. This prompted measurements in a home for asylum seekers, where insect pests had been controlled regularly by a commercial firm; here the presence of various biocides was demonstrated. As the insecticides could not be sufficiently decontaminated, the further administration was discontinued and instead cockroach traps and baits were set up. This alternative method which was well accepted by the inhabitants of the home as well as the administrative staff was subsequently successfully employed in other public institutions, e.g. a school and another kindergarten.

Should landholders be allowed to make commercial gain or profit from animal pests? This is an issue not only with wild pigs but also with other pests, and there are different opinions about the effect of commercial use of a pest. Two broadly opposed views exist:
(a) Commercial use of a pest results in its conservation (or reduced control) by landholders, because they can profit from the pest population.
(b) The possibility of commercial gain results in greater harvesting or hunting pressure on a species, thus reducing its population.
Either effect is possible, depending upon the identifiable circumstances. Under some circumstances, commercial use leads to greater conservation of a pest, but under other circumstances – circumstances that seem to be more likely in the case of pigs – commercial use results in increased control of a pest population. Commercialization is an important strategy to consider in managing a pest.
Landholders have two main ways in which they can make commercial gain from wild pigs:
(a) Landholders may obtain income from fees charged to amateur pighunters for hunting, camping, accommodation, etc.
(b) By selling the rights to hunt pigs to commercial hunters, or by hunting pigs themselves and selling their harvest to meat producers, landholders can gain if wild pigs are used in the meat trade.
This chapter concentrates on the first possibility – an income from amateur pighunters' fees – and the next chapter deals with the second possibility.

A variety of fresh market vegetables, including watermelon and tomato are economically important crops in Florida. Whitefly-transmitted Squash vein yellowing virus (SqVYV) was first identified in squash and watermelon in Florida in 2005 and shown to cause a severe decline of watermelon vines as crops approach harvest. Florida is most economically impacted by SqVYV, although the virus has been detected more recently in Indiana and South Carolina. The origin and evolutionary history of SqVYV, one of the few members of the genus Ipomovirus within the family Potyviridae, are not known. Sequence diversity of SqVYV isolates collected at different times, from different locations and from different plant species is being analyzed for insights into the origin of the virus. More recently, Cucurbit leaf crumple virus (CuLCrV) and Cucurbit yellow stunting disorder virus (CYSDV), also whitefly-transmitted, have been detected in watermelon in Florida. Tomato yellow leaf curl virus (TYLCV) was first detected in south Florida tomato crops in 1997. Several surveys have been conducted in the region to identify alternative hosts for these four viruses. Cucurbit weeds including Balsam-apple (Momordica charantia), creeping cucumber (Melothria pendula) and smellmelon (Cucumis melo var. dudaim) provide reservoirs for SqVYV, CuLCrV and/or CYSDV. Green bean (Phaseolus vulgaris) also can be a reservoir for CuLCrV. No wild hosts of TYLCV have been reported in Florida. The effectiveness of insecticides and silver plastic mulch to manage whiteflies and mitigate TYLCV has been demonstrated and is currently being evaluated for SqVYV, CuLCrV and CYSDV. In addition, potential sources of SqVYV resistance have been identified in greenhouse and field screening of watermelon germplasm. Further studies to refine these sources of resistance are underway. Lastly, a comprehensive map of 33,560 hectares (82,928 acres) of vegetable fields in the three counties comprising the majority of the southwest Florida vegetable production area has been developed to identify 'hot spots' and reservoir crops for viruses and whiteflies, and will be useful in evaluation of management strategies to decrease virus incidence in commercial fields.

One of the essential requirements of current agricultural practice is the need to evolve towards crop techniques that make better use of productive factors behaving in sustainable and environmentally respectful ways. Pest control is one of the most important problems to take into account, due to the significant production losses that pests may cause. The Integrated Production for olive crop defines a set of rules that has to be followed in order to ensure a production of higher quality, and promotes an environmentally respectful model of Olive cultivation. This work presents SAIFA (spanish acronym for Sistema de Alerta e Información Fitosanitaria Andaluz -Andalusian Phitosanitary Information and Alert System) a webbased information system which allows monitoring the Integrated Production for the olive crop in Andalusia, Spain. SAIFA has been built as a tool to assist agricultural technicians to comply with the quality standards of Integrated Production, and to help decision makers to choose the actions to be performed in the crop. Also, it assists coordinators to choose an Integrated Production strategy applicable for the whole region with the main objective of ensuring the safety of crops and reporting the current phitosanitary state to the authorities.

Four ecdysone agonists, RH-5849, RH-5992, RH-0345, and RH-2485, were tested for toxicity against fifth-instar larvae of Choristoneura fumiferana. RH-2485 was the most toxic (LD 50 ϭ 1.05 ng/larva) followed by RH-5992 (LD 50 ϭ 8.8 ng/larva), RH-0345 (LD 50 ϭ 41.0 ng/larva), and RH-5849 (LD 50 ϭ 236.9 ng/ larva). The relative potencies of these compounds to induce the transcription factor Choristoneura hormone receptor 3 (CHR3) was studied. Detectable levels of CHR3 mRNA were induced by RH-2485 at a concentration as low as 1.5 ng/larva, but similar inductions required concentrations as high as 7.5 ng of RH-5992/ larva, 37.5 of RH-0345/larva, and 187.5 of RH-5849/larva. The order of potency of these four ecdysone agonists for inducing CHR3 mRNA is the same as their larval toxicity. ᭧1998 Academic Press

The rotation length is a key component of even-aged forest management systems. Using Fennoscandian forestry as a case, we review the socioecological implications of modifying rotation lengths relative to current practice by evaluating effects on a range of ecosystem services and on biodiversity conservation. The effects of shortening rotations on provisioning services are expected to be mostly negative to neutral (e.g. production of wood, bilberries, reindeer forage), while those of extending rotations would be more varied. Shortening rotations may help limit damage by some of today's major damaging agents (e.g. root rot, cambium-feeding insects), but may also increase other damage types (e.g. regeneration pests) and impede climate mitigation. Supporting (water, soil nutrients) and cultural (aesthetics, cultural heritage) ecosystem services would generally be affected negatively by shortened rotations and positively by extended rotations, as would most biodiversity indicators. Several effect modifiers, such as changes to thinning regimes, could alter these patterns. Keywords Climate change Á Forest damage Á Non-timber forest products Á Production Á Recreation Á Timber Ó The Author(s) 2016. This article is published with open access at Springerlink.com www.kva.se/en

We investigated, (i) whether the emergence from pupation of two coleopteran pest insect groups in oilseed rape (OSR, Brassica napus L.)pollen beetles (Meligethes spp. F., Nitidulidae) and stem weevils (Ceutorhynchus pallidactylus Marsh and C. napi Gyll., Curculionidae)-is affected by the exclusion of ground-dwelling predatory arthropods, and (ii) the role for pest control of the widely abundant carabid beetles Anchomenus dorsalis Pontop. and Poecilus cupreus L. Densities of ground-dwelling arthropods were manipulated using enclosures; emerging pest adults were assessed using emergence traps. Where arthropods had been excluded, between two (June sampling) and tenfold (August sampling) more stem weevils emerged than where predators had free access. The addition of 25 adult A. dorsalis m -2 to formerly predator-free enclosures showed similar stem weevil emergence than plots where predators had free access; the addition of 25 adult P. cupreus m -2 did not reduce stem weevil emergence. In August, both A. dorsalis and P. cupreus additions marginally significantly reduced pollen beetle emergence.

There are low toxicity substances and others that involve
risks for human health. For this reason, governments all
over the world have enforced specific legislation.
Pesticides, also called agrochemicals or plant protection products, are compounds
that are applied to crops to protect them from pests and diseases and increase yields. Among
them, there are low toxicity substances and others –that in certain concentrations- have
carcinogenic risks or may cause endocrine disorders. For this reason, governments around
the world have developed specific legislation.

The Lodi-Woodbridge Winegrape Commission Crush District 11 was created by referendum during the summer of 1991. The commission conducts extensive on-farm research trials and demonstration projects in cooperation with the University of California, the California State University system and local growers. The results have been disseminated through a series of regular grower meetings, seminars and an IPM newsletter sponsored by the commission and widespread coverage in the agriculture and general media. Several pest management practices which could reduce pesticide inputs have been promoted by the commission's IPM Program, and others are being further validated or are being researched for applicability to growers in the area. The research falls into two distinct categories. The ®rst category of research is evaluation of the ef®cacy of recommended practices and includes economic analysis and the collection of biological data to evaluate performance from the perspectives of vineyard ecology, input use, and pro®tability. Intensive study of 10 growers over 2 years showed a highly variable level of adoption. The yield response to pest control inputs showed increasing returns up to the level of inputs of $375 per hectare after which returns leveled off. The second category of research is the development of alternative practices through onfarm controlled trials. The results of 3 on-farm trials are reported. A cover crop trial showed a reduction of pests in 1995 but no difference in 1994 between the cover cropped and bare soil blocks. Yellow sticky bands signi®cantly reduced the number of leafhoppers in a trial vineyard, but was not as effective as pesticide treatments. The comparison of four alternative weed management techniques demonstrated that the use of an in-row cultivator is more effective than preemergent herbicides or mulch placed along the vine row in controlling weeds. A visual sprayer was shown to reduce the use of contact herbicide. The on-farm approach to all of the research and the`in your own backyard' nature of the meetings has created the sense of ownership for the growers that has been instrumental in achieving grower support. The public nature of the information provided by the commission and grower members to all winegrape producers implies a recognition among members of their interdependence and the long-term bene®ts of reducing pesticide use as a group. The recognition of interdependency is crucial for any group trying to form an IPM district.

Biofouling is a serious problem in industrial recirculating cooling systems. It damages equipment, through biocorrosion, and causes clogging and increased energy consumption, through decreased heat transfer. In this research a fixed-bed biofilter was developed which removed assimilable organic carbon (AOC) from process water, thus limiting the major substrate for the growth of biofouling. The biofilter was tested in a laboratory model recirculating cooling water system, including a heat exchanger and a cooling tower. A second identical model system without a biofilter served as a reference. Both installations were challenged with organic carbon (sucrose and yeast extract) to provoke biofouling. The biofilter improved the quality of the recirculating cooling water by reducing the AOC content, the ATP concentration, bacterial numbers (30-40 fold) and the turbidity (OD 660 ). The process of biofouling in the heat exchangers, the process water pipelines and the cooling towers, was monitored by protein increase, heat transfer resistance, and chlorine demanded for maintenance. This revealed that biofouling was lower in the system with the biofilter compared to the reference installation. It was concluded that AOC removal through biofiltration provides an attractive, environmental-friendly means to reduce biofouling in industrial cooling systems. r

In a context of stark opposition between supporters and opponents to the wolf, the extent to which this particular predator is dangerous for humans is still an open question.
What lies beneath the negative perception of the wolf?
What should be the historian's contribution, based on historical sources and historical methods?
Thanks to a database of 4,700 cases of wolf attacks on human having occurred in France between 1580 and 1880, it is now possible to grasp the chronological evolution and spatial evolution of wolf related risks.
Undeniably real, though mostly belonging to a remote past, and statistically rare, though anthropologically intolerable, these attacks point to two opposite groups, predatory wolves occasionally preying on humans on one hand, rabid wolves striking indiscriminately a whole population on the other.
The attacks of the first kind occurred regularly in an unsafe environment, and gave rise to tales of "Ferocious Beasts" in times of dramatic crisis (1594-1600, 1691-1694, 1746-1750, 1764-1767, 1814-1819).
The second kind was spatially and chronologically less widespread, but sowed the seeds of mass hysteria, all the more persistent since the underlying sickness it forebode remained without a cure before the last third of the 20th century.
The conclusion between these two different realities gave Canis Lupus its negative aura, significantly dimmed recently however since it has entirely lost its material basis, at least in France.

The population dynamics and parasitoid assemblages of two leafminers, Liriomyza helianthi Spencer and Calycomyza platyptera (Thomson) (Diptera: Agromyzidae), were examined over a 3-year period. Leafminers were sympatric and occurred together on the same two host plants, Helianthus annus L. and Xanthium strumarium L., at our study sites in northern California. Sixteen species of parasitoids were reared from the two leafminers and mortality from parasitoids was substantial, averaging about 74%. The most common species, such as Diglyphus spp. and Neochrysocharis arizonensis Crawford, show no bias in association with a particular leafminer or plant species. Of the remaining parasitoids, most were usually associated with a particular leafminer species (e.g., Opius dimidiatus [Ashmead] on L. helianthi). Only one parasitoid of the seven most common taxa (Chrysocharis ainsliei Crawford) was strongly associated with a particular host plant species (H. annuus) in either leafminer host. In addition, a review of the literature found that parasitoid assemblages in natural, unmanaged habitats tended to be more species rich than assemblages of parasitoids on leafminers in agricultural habitats, although significant heterogeneity occurs among studies. Nevertheless, the most common genera of parasitoids attacking leafminers (Diglyphus, Chrysocharis, Neochrysocharis, Opius) are prevalent in both habitats. Given the similarity in assemblages of many of the parasitoids attacking leafminers in managed and natural habitats and frequent proximity of the two habitats, there exists the potential for exchange of natural enemies among habitats, potentially enhancing pest control in agricultural areas.

East Africa and Pakistan are currently suffering from the worst invasion of desert locusts in decades. Threatening agricultural production in East Africa, the assault increases the danger of famine in a region where 19 million people already face food insecurity. When locust invasions such as the current ones occur, journalists like to refer to them as "biblical" implying that these disasters are analogous to the ones described in the Bible or by classical writers. However, as this article will illustrate, locust invasions are neither acts of providence nor ancient disasters. In fact, they result from the interplay between natural and human factors and they have been of great concern to western governments in the 19th and 20th centuries, first within the scope of colonial empires, then as a consideration of international development policies.

Rahaman and Afrin Akter Bhuiyan (2015). Effect of Commonly Used Botanicals on the Yield and Yield Contributing Characters of Cabbage by Controlling Tobacco Caterpillar Spodoptera litura (Fab.). Int. J. Bus. Soc. Sci. Res. 3(4): 204-209. Retrieve from Abstract The experiment was conducted in the field of Sher-e-Bangla Agricultural University farm, Sher-e-Bangla Nagar, Dhaka, Bangladesh during the period from November 2013 to February 2014 to study the effectiveness of commonly used botanicals on the growth and head formation of cabbage by managing tobacco caterpillar, Spodoptera litura (fab.). using variety was cabbage Hatlas-70. The experiment comprised of the following treatments-T 1 : Neem oil @ 6 ml/L of water, T 2 : Neem oil @ 5 ml/L of water, T 3 : Neem oil @ 4 ml/L of water, T 4 : Mehgoni seed kernel @ 200 mg/L of water, T 5 : Neem leaf extract @ 200 mg/L of water, T 6 : Neem seed kernel extract @ 200 mg/L of water and T 7 : Untreated control. Treatments were applied at 7 days intervals starting from the first initiation of the pest attack. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. It was revealed that the maximum thickness of head (13.28 cm) was recorded in T 1 , while the minimum thickness (10.56 cm) was found in T 7 (untreated control). The maximum diameter of head (11.34 cm), the highest gross yield per plant (2.02 kg), and The highest marketable yield per hectare (65.56 ton) was recorded in T 1 treated plot, while the minimum diameter (9.34 cm), the lowest gross yield per plant (1.52 kg) and the lowest marketable yield per hectare (42.96 ton) observed in T 7 treatment respectively. The highest benefit cost ratio (3.52) was estimated for T 1 and the lowest (1.86) for T 4 treatment under the trial. From the findings it was revealed that spraying of Neem oil @ 6 ml/L of water at 7 days interval was more effective among the commonly used botanicals for reduction of cabbage plant infestation by tobacco caterpillar.

National pesticide reduction targets have largely been based on a percentage reduction in either the number of sprays applied or tonnage of pesticide used or both. These approaches imply a uniformity in pesticide use among the farmers comprising the industry. Data from a three-season integrated pest and disease management study in New South Wales, Australia, showed over 200% variation in the number of both fungicide and insecticide sprays applied by different apple growers in the same season. The total amount of pesticide applied (in kilograms per hectare) also varied between farmers by around 200%. Regression analysis showed no correlation between the number of fungicide sprays applied and the percentage of fruit infected with apple scab or between the number of insecticide sprays and the amount of insect damage recorded. Observations were made in ten orchards where pest and disease levels were monitored and advice given, and in a further ten orchards where no advice was provided. Decisions on fungicide use were left to the farmers in both groups, but advised growers were requested to use reduced rates of protectant fungicides. Pest control recommendations were based on thresholds. Except in the first season, when advised growers used more fungicide treatments, there was no difference in mean pesticide use by the two groups. Anecdotal information suggests that variation in acceptance of risk accounts for a large proportion of the differences in pesticide use in different orchards. The consequences of these findings in establishing pesticide reduction strategies are discussed.

Between 1995 and 2002, a massive appearance of black widow (Latrodectus mactans tredecimguttatus, Rossi 1790) was recorded along the Croatia coast. This paper gives a historical review of latrodectism and observations from Istria and Dalmatia, paying particular attention to the spider's habitat. There are several reasons for the black widow to appear in a new habitat such as the introduction of leguminous plants, watermelons and melons where crops were grown earlier. Black widow can also be found near buildings and gardens. Human contacts with the spider are usually without consequences for humans, thanks to education and a relatively good visibility of the spider. The authors describe their experience in fighting black widow and emphasise the importance of education in preventing lactrodectism.

Since 1982, Stephen J. Gould and Elisabeth Vrba’s concept of exaptation has been adopted, to varying degrees, by a number of biological and social science disciplines. However, it remains a missing term in the study of archaeologically recovered insect remains and entomologically-related artefacts. Exaptation refers to the process by which a characteristic acquires a function for which it was not originally adapted. The application of Gould and Vrba’s concept to the field of archaeoentomology could enhance our perception of past social, environmental, and climatic conditions as well as interactions. Herein, biological and technological examples of the enduring relationship between synanthropic insects and humans are explored using exaptation.

Spraying of a commercial formulation of Bacillus thuringiensis and an easy-to-prepare aqueous leaf extract of 1 of 3 botanicals, namely neem (Azadirachta indica), ayapana (Ayapana triplinervis) and vieille fille (Lantana camara), on alternate weeks showed good pest control properties, against the Lepidopteran pests Plutella xylostella and Crocidolomia binotalis, in field cabbages. The treatments were found to be as effective as the recommended synthetic organophosphate insecticide, Tokuthion. The botanicals had an enhancing influence on the Bt, the combination treatments being more efficient than the individual botanical or Bt treatments alone. Such an integrated approach has important implication in the environmentally-safe control of pests

Advances in mass-production and formulation technology of entomopathogenic nematodes, the discovery of numerous isolates/ strains and the desirability of reducing pesticide usage have resulted in a surge of scientific and commercial interest in these nematodes. The lessons learned from earlier problems have encouraged scientists and leading commercial companies to increase their efforts toward improving cost efficiency and better product positioning in the market within the confines of product capabilities. The successes or failures of the nematodes against 24 arthropod pest species of agriculture and animals and against a major slug pest in agriculture are discussed in this review. Commercial successes are documented in markets such as citrus (Diaprepes root weevil), greenhouses and glasshouses (black vine weevil, fungus gnats, thrips, and certain borers), turf (white grubs, billbugs, and mole crickets), and mushrooms (sciarid flies). In addition, the successful commercialization of a nematode (Phasmarhabditis hermaphrodita) against slugs in agricultural systems is presented. Despite this progress, the reality is that nematode-based products have limited market share. Limited share is attributed to higher product cost compared to standard insecticides, low efficacy under unfavorable conditions, application timing and conditions, limited data and cost benefit in IPM programs, refrigeration requirements and limited room temperature shelf life (product quality), use of suboptimum nematode species, and lack of detail application directions. One or more of these factors affected the market introduction of the nematodes despite promising field efficacy against insects such as black cutworm in turf, sugar beet weevil in sugar beet, sweet potato weevil in sweet potato, and house fly adult in animal-rearing farms. Insects such as cabbage root maggots, carrot root weevil, and Colorado potato beetle are listed on the label of certain commercial products despite low efficacy data, due to insect susceptibility, biology, and/or behavior. To make entomopathogenic nematodes more successful, realistic strategies through genetic engineering, IPM programs, and new delivery systems and/or training programs to overcome their inherent cost, formulation instability, and limited field efficacy toward certain insects are needed.

ABStrAct: An electronic spreadsheet is described which helps users to design, equip and operate facilities for the mass rearing of insects for use in insect pest control programmes integrating the Sterile Insect Technique (SIT). The spreadsheet was designed based on experience ...

Photostability, spray solution pH, and interaction of
profenfos, emamectin benzoate, and spinosad or their binary
mixtures against larvae of the cotton leafworm, Spodoptera
littoralis were evaluated. Laboratory bioassays of larval
mortality on field-treated castor bean leaves showed that
residual efficacy of emamectin benzoate, spinosad and
profenfos exhibited high level of activity against the 2nd and
4th instar larvae of S. littoralis at 16, 18 and 22 days after
application. Studies were conducted in the laboratory to
investigate how the addition of insecticides to different
samples of Nile River water would affect the pH of spray
mixtures. The pH values of five Nile River water samples
were alkaline; as they were significantly different and
ranged from 7.8 to 8.2 while pH of tap water was 7.4. Results
showed that the spray solutions remained alkaline following
addition of the three tested insecticides. Mortality
percentages of the 4th instar larvae of S. littoralis significantly
decreased when profenfos diluted in alkaline phosphate
buffer (pH 8 or more). Also, diluting emamectin benzoate
and spinosad in phosphate buffer (pH 4 to 9) indicated that
the optimal pH of spray solutions was ranged between 6 and 7. When emamectin benzoate, spinosad and profenfos tested
alone against the 4th instar larvae of S. littoralis, the
calculated LC50 values were 0.712, 20.02 and 253 ppm,
respectively, 24 hr post-treatment. Such value was decreased
to 0.353, 16.25 and 231.5 ppm, respectively, 48 hr posttreatment.
Present results indicated that there was an
antagonistic effect of profenfos when mixed either with
emamectin benzoate or spinosad. While there was an
additive effect of the binary mixture of emamectin benzoate
with spinosad.

The use of plant-feeding predators for biological pest control has traditionally been neglected, mainly due to the risk of them feeding on crop plants and causing economically significant damage. Yet, these predators offer advantages for biological pest control. They are mostly generalist predators that have an impact on several crop pests. They may also be able to establish on crops early in the growing season, when pests colonize them, and can remain on the target crop when prey is scarce. Therefore, management programs must seek to minimize risks while maximizing benefits. In vegetable crops, most of the literature on zoophytophagous predators has focused on four species: Dicyphus tamaninii, Dicyphus hesperus, Macrolophus pygmaeus and Nesidiocoris tenuis (Heteroptera, Miridae). The capacity of these species to produce crop damage in tomatoes varies. This damage has been related to relative predator-toprey abundance, with damage increasing at high predator abundances and low prey densities. In this review, we analyze the use of these species in biological control programs and the associated benefits and risks. The differences in the damage caused by the four predatory species examined could not be attributed to either stylet morphology or saliva composition. However, feeding on specific plant structures where they may find the resources required for their development is what probably determines feeding damage. Understanding when and why these predators increase their feeding on plants or on certain plant parts is of crucial importance for integrating them in biological control programs.

Intercropping has a 1000-year old history in Chinese agriculture and is still widespread in modern Chinese agriculture. Nowadays, agricultural systems in China are stigmatized to exhaust high levels of input factors like N fertilizer or irrigation water and to contribute severely to environmental problems like desertification, river eutrophication, soil degradation and greenhouse effect. In this context, monocropping systems have to be revised and may not be the best performing systems any more, considering sustainability, income security and nutritional diversity in rural areas. Therefore, intercropping systems offer alternatives for a more sustainable agriculture with reduced input and stabilized yield. Especially in the last decade this cropping system has been rediscovered by scientific research. Studies showed increased yield of maize and wheat intercropped with legumes: chickpea facilitates P uptake by associated wheat, maize intercropped with peanut improves iron nutrition and faba bean enhances N uptake when intercropped with maize. China's intercropping area is the largest in the world. Nevertheless, there are only few international studies dealing with intercropping distribution, patterns and crops. Most studies deal with nutrient-use efficiency and availability. This study is a first approach to gain an overview of intercropping history, basic factors about interspecific facilitation and competition and distribution of Chinese intercropping systems. Finally, four intercropping regions can be distinguished and are explicitly described with their intercropping intensity, potential and conditions.

The 1989 collapse of trade relations with the former socialist bloc plunged Cuba into an economic and food crisis. Cuban farmers, scientists, and planners have responded with alternative agricultural technology to make up for imported food and Green Revolution inputs that are no longer available. A review of Cuban experience to date with biological pest control practices shows that, on the one hand, significant progress has been made that may serve as a model for other countries, while, on the other hand, there still remains a ...

Cholinesterase inhibitors have been used in the treatment of human diseases, the control of insect pests, and more notoriously as chemical warfare agents and weapons of terrorism. Most uses of cholinesterase inhibitors are based on a common mechanism of action initiated by inhibition of acetylcholinesterase (AChE). Extensive inhibition of this enzyme leads to accumulation of the neurotransmitter acetylcholine and enhanced stimulation of postsynaptic cholinergic receptors. This action is beneficial in cases where a reduction in cholinergic transmission contributes to clinical symptoms, e.g., low muscle tone in the autoimmune disorder myasthenia gravis due to loss of nicotinic receptors. Under normal conditions, however, extensive inhibition of AChE leads to excess synaptic acetylcholine levels, over-stimulation of cholinergic receptors, alteration of postsynaptic cell function and consequent signs of cholinergic toxicity. This biochemical cascade forms the basis for the use of anticholinesterase insecticides in pest control as well as for nerve agents in chemical warfare. Paradoxically, the short-acting cholinesterase inhibitor pyridostigmine, an important therapeutic agent in the treatment of myasthenia gravis, was used during the Persian Gulf War to prevent the long-term clinical consequences of possible organophosphate nerve agent exposure. As shown in the attacks in Matsumoto and Tokyo, these same nerve agents can be effectively used to inflict urban terror. Cholinesterase inhibitors thus share a common mechanism of pharmacological or toxicological action, ultimately modifying cholinergic signaling through disruption of acetylcholine degradation. While the use of cholinesterase inhibitors relies on their interaction with AChE, a variety of reports indicate that a number of cholinesterase inhibitors have additional sites of action that may have pharmacologic or toxicologic relevance. A variety of esterase and non-esterase enzymes, neurotransmitter receptors and elements of cell signaling pathways are targeted by some anticholinesterases. In some cases, these actions may occur at concentrations/dosages below those affecting cholinergic transmission. Studies of interactive toxicity of binary mixtures of common organophosphorus insecticides indicate that non-cholinesterase targets may be important in cumulative toxicity. Exposure to multiple anticholinesterases having selective effects on other macromolecules could confound the assumption of additivity in cumulative risk assessment. Knowledge of such selective additional targets may aid, however, in the optimization of strategies for poisoning therapy and in the further elucidation of mechanisms of toxicity for this class of compounds.

What resources should be committed to the control of invasive species? This study is based on a survey of nature conservation and forestry authorities, wildlife trusts and private landowners which investigated the extent of the ecological and economic impacts of the invasive nonnative plant Rhododendron ponticum in the British Isles. There are data on 52,000 ha of land affected by R. ponticum, more than 30,000 ha of it in nature reserves. For nearly all nature reserves, displacement of native species and habitat changes were both reported. In 2001, respondents controlled 1275 ha of R. ponticum at a cost of £670,924. To test the optimality of this, we apply a model of social expenditure. The external costs of R. ponticum control are estimated from the probability that it will spread to contiguous sites and the damage done on invaded sites. These are then used to calculate the socially optimal level of expenditure on R. ponticum control, and the funding gap it identified by comparing the result with current levels of expenditure. The results suggest that a socially optimal level of control effort requires a significant increase in social funding for R. ponticum control, although the size of the increase varies between landholders. q

This paper analyses the English language needs of service technicians in the pest control industry. The paper aims to provide a detailed understanding of the communication requirements in the workplace in order to develop a language course appropriate for their needs. In the pest control industry, service technicians are known to be the first point of contact with the customers. The nature of their job involves servicing customers' premises either weekly, biweekly or monthly. This calls for interaction with customers, which requires the ability to perform communicative functions to address customer inquiries and handle their requests and complaints. This paper utilises a needs analysis questionnaire for data collection. The questionnaire was administered to 20 service technicians in the Klang Valley. The result indicates the service technicians are often involved in communication activities: introduction; describing services, processes and people; telephone communication; responding to complaints and; giving suggestions and providing advice that relates to pest control. The findings also reveal that the essential skills that pest control service technicians need for efficient job performance are listening and speaking skills; thus, any course to enhance English language proficiency among this group of service providers should centre on these two skills.

Agricultural intensification has resulted in a simplification of agricultural landscapes by the expansion of agricultural land, enlargement of field size and removal of non-crop habitat. These changes are considered to be an important cause of the rapid decline in farmland biodiversity, with the remaining biodiversity concentrated in field edges and non-crop habitats. The simplification of landscape composition and the decline of biodiversity may affect the functioning of natural pest control because non-crop habitats provide requisites for a broad spectrum of natural enemies, and the exchange of natural enemies between crop and non-crop habitats is likely to be diminished in landscapes dominated by arable cropland. In this review, we test the hypothesis that natural pest control is enhanced in complex patchy landscapes with a high proportion of non-crop habitats as compared to simple large-scale landscapes with little associated noncrop habitat. In 74% and 45% of the studies reviewed, respectively, natural enemy populations were higher and pest pressure lower in complex landscapes versus simple landscapes. Landscape-driven pest suppression may result in lower crop injury, although this has rarely been documented. Enhanced natural enemy activity was associated with herbaceous habitats in 80% of the cases (e.g. fallows, field margins), and somewhat less often with wooded habitats (71%) and landscape patchiness (70%). The similar contributions of these landscape factors suggest that all are equally important in enhancing natural enemy populations. We conclude that diversified landscapes hold most potential for the conservation of biodiversity and sustaining the pest control function.

Three laboratory experiments were conducted at the University of Zimbabwe to determine if the native ladybird beetles found in the Department of Crop Science field plots can survive on possible alternative diets of bee pollen, dried ground chicken liver and shredded tuna for consideration in mass laboratory rearing. The native species investigated were Cheilonomes geisha, C. sulphurea, C. lunata and Hippodamia variegata. The fourth experiment was to evaluate feeding behaviour of the beetles on Cowpea aphids, Aphis craccivora and to identify the particular species effectively feeding on the aphids. All the experiments had three treatments which were the three species of ladybird beetles with blocking by day for each day the experiment was conducted. A feeding sample of 30mg of the food source was presented to individual beetles in petri dish and weight changes measured after two hours. The feeding samples of a particular treatment were then averaged as per each day the experiment was conducted. The experiments on alternative food diets showed they could not sustain the beetles as there was no significance. There was significance (P = 0.008) for the experiment on aphids, and the box plot showed C. lunata to be the most effective aphids consumer. Results suggest that, although an alternative diet for mass laboratory rearing of the beetles was not found, C. lunata was the most suitable biological control agent for A. craccivora. There is need for further research on possible alternative diets for cost effective mass laboratory rearing of C. lunata for sustainable control of A. craccivora.

Zambia is a country with an extensive mining industry with the majority of mines located in the Copperbelt province. Through this region of the country, the Kafue River drains and receives effluent water from mining activities as well as from other industrial point sources. In addition, production of agricultural products and pest control requires use of different pesticides in the area. Information on industrial and agricultural pollution has not been clearly identified in Zambia, and little attention has been paid to pollution control and possible impact of metals, pesticides, and other persistent compounds in the environment. The objective of this study was to introduce and to evaluate a few methodologies based on in situ bioassays for environmental assessment to promote sustainable and environmentally sound water resource management of the Kafue River. The results show that caged threespot tilapia exposed downstream of industrial points sources rapidly bioaccumulate several trace elements, i.e., Cd, Co, Cu, Cr, Ni. These elements also occurred in much higher concentrations in water samples downstream of the industrial area compared with a locality upstream. Furthermore, the use of a semipermeable membrane device (SPMD) for passive absorption of lipophilic pollutants in the water showed relatively high concentration of several pesticides, i.e., DDT with major metabolites, PCB, and dieldrin. The present study shows that only 2 weeks of in situ studies in waters contaminated by pollutants affects in situ exposed fish and that the correlation between water and tissue concentrations was relatively good. Both trace elements and persistent organic pollutants occurred in such high concentrations that they must be considered from ecotoxicological aspects and may affect aquatic animal health.