Pests aggregation

Language (ACSL), application, 30 Agenda setting, mass media, 158 Aggregation, pests, 80... 

The development of processes to determine aggregate and cumulative exposures adequately to pesticides will require the use of sophisticated modeling practices to generate sufficient data to guide such assessments. An accurate knowledge of pesticide use and pest management practices is essential to modeling efforts. 

Joosse E. N. G. and Koelman T. A. C. M. (1979) Evidence for the presence of aggregation pheromones in Onychiurus armatus (Collembola) a pest insect in sugar beet. Entomol. Exp. Appl. 26,... 

Bartelt R. J., Dowd P. F. and Plattner R. D. (1991) Aggregation pheromone of Carpophilus lugubris new pest management tools for the nitidulid beetles. In Naturally Occurring Pest Bioregulators, ed P. A. Hedin, pp. 27 -0. ACS Symposium Series No. 449, American Chemical Society, Washington, DC. 

It has been discovered that the crucifer flea beetle, Phyllotreta cruciferae Goeze, a significant pest of oilseed Brassica and other cruciferous crops in North America and Europe, uses a hydrocarbon pheromone. The first published evidence for a pheromone in P. cruciferae was that canola plants infested by unsexed adults were more attractive to both males and females than damaged plants only, in both laboratory and field bioassays (Peng and Weiss, 1992). Subsequently, Peng et al. (1999) determined with field bioassays that the males were the attractive sex, fitting the pattern of a male-produced aggregation pheromone. 

Female boll weevils (a cotton pest) produce two isomeric compounds that aggregate die males for food and sex. A few mg of two isomeric active compounds, grandisoland Z-ochtodenolwere isolated from 4.5 million insects. Suggest structures for diese compounds from die spectroscopic data below. Signals marked exchange widi D2O. 

Decane is an alarm pheromone of the ant C. obscuripes866 Decanal (A95) is a pheromone component of larvae of C. pomonella (see Section 4.04.5.3.7),382 and is used by the red bug C. lectularius as an aggregation pheromone component.193 Males of a long-horned beetle, the coffee white stem borer Xylotrechus quadripes, a serious coffee pest in India, produce (S)-2-hydroxy-3-decanone (A96) as sex pheromone to attract female beetles.393 9-Oxo- (A97) and 9-hydroxydecanoic acid (A98) are the major sex pheromone components of females of the scoliid wasp Campsoscolia ciliata. Interestingly, the orchid Ophrys speculum also produces these compounds to attract males of Campsoscolia for pollination.394 ( )-4-Decanolide (A99)... 

Very recently (R, S )-4-methyl-5-hydroxy-3-heptanone has been identified as the major component of the aggregation pheromone of the rice weevil, sltophilus orvzae L., and the maize weevil, S. zeamals Motsch. (28). This compound is obviously very different in structure from the previously identified curculionid pheromones. In fact, it is very similar to the pheromone of two other stored-products pests, the drugstore beetle and the cigarette beetle, which are in the family Anobiidae (see later). Undoubtedly, we will find more diversity in structure as more curculionid pheromones are identified. 

The Food Quality Protection Act (FQPA) in the USA and the Pest Control Products Act (PCPA) in Canada mandate that potential risks to infants and small children be specifically addressed. When assessing the food use of a pesticide, in order to assure that there is a reasonable certainty that no harm will result to infants and children from aggregate exposure to the pesticide s chemical residues , the FQPA and PCPA in the case of threshold effects call for an additional tenfold margin of safety for the pesticide chemical residue and other sources of exposure to be applied to estimating risks to infants and children. A different margin of safety may be used only if, on the basis of reliable data, such a margin will be safe for infants and children. In Canada, these same requirements also apply to non-food-use pesticides. 

PMRA (2003). General Principles for Performing Aggregate Exposure and Risk Assessments, Science Policy Notice, SPN2003-04, Pest Management Regulatory Agency, Ottawa, ON, Canada (website http //www.hc-sc.gc.ca/pmra-arla). 

Common mynahs are also considered pests where they develop large, communal roosts, which can involve dense aggregations of thousands of birds. These are considered nuisances because of the raucous noise, and the copious excrement that can accumulate. 

At a much smaller scale, pest density can vary tremendously within a given region. This is particularly true with soil-borne fungi and arthropods. Two adjacent fields may have densities that vary by several orders of magnitude. With pests that move in the air, there will be less aggregation than this, but differences can still be large. Unfortunately, it is still not a wide-spread practice to assess pest densities in fields in order to properly determine the need to use a pesticide. There are obvious exceptions, however, which fall under the concept of Integrated Pest... 

Such thresholds, however, are difficult to determine experimentally. For instance, at low pest density (where the threshold is likely to be) there is great within-field variation and pest aggregation. 

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