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Crop Area (crop + area)
Selected AbstractsConsumer attitudes and acceptance of genetically modified organisms in KoreaINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2003Hyochung Kim Genetically modified organisms (GMOs) were first used to designate micro organisms that had had genes from other species transferred into their genetic material by the then-new techniques of ,gene-splicing.' Cultivation of GMOs has so far been most widespread in the production of soybeans and maize. The United States holds almost three-fourths of the total crop area devoted to GMOs. Because many crops have been imported from the US, there is a large possibility for consumers to intake the products of GMOs in Korea. The safety of GMOs is not scientifically settled at this time, however. Additionally, the research regarding the GMOs issue of consumers has rarely been conducted in Korea. This study therefore focused on the consumer attitudes about GMOs and willingness to purchase them. The data were collected from 506 adults living in Seoul, Daegu and Busan, Korea, by means of a self-administered questionnaire. Frequencies and chi-square tests were conducted by SPSS. The results of the survey were as follows. First, the consumer concerns about GMOs were high but recognition was low; many respondents answered they did not have exact information about GMOs, although they had heard about them. Second, almost 93% of the respondents desired the labelling of GMOs. Third, the level of acceptance of GMOs was high; two-thirds of the respondents showed that they were willing to buy GMOs. Finally, many respondents worried about the safety of GMOs in that 73% of the respondents primarily wanted to be informed about safety of GMOs. This study suggests that the consumer education about GMOs should be conducted through mass media and consumer protection organisations. [source] Refuge habitats modify impact of insecticide disturbance on carabid beetle communitiesJOURNAL OF APPLIED ECOLOGY, Issue 2 2001Jana C. Lee Summary 1Carabid beetles are polyphagous predators that can act as biological control agents of insect pests and weeds. While current agricultural practices often create a harsh environment, habitat management such as the establishment of within-field refuges has been proposed to enhance carabid beetle abundance and impact. We examined the joint effects of refuge habitats and insecticide application on carabid activity density (parameter of population density and relative activity) and species composition in a cornfield. 2Our 2-year study comprised four treatments: (i) ,refuge/,insecticide; (ii) +refuge/,insecticide; (iii) ,refuge/+insecticide; (iv) +refuge/+insecticide. Refuge strips consisted of grasses, legumes and perennial flowering plants. ,,Refuge' strips were planted with corn and not treated with insecticide. 3Before planting and insecticide application, carabid activity density in the crop areas was similar across all treatments. Insecticide application immediately reduced carabid activity density and altered community composition in the crop area. 4Refuge strips had significantly higher activity density of beetles than ,refuge strips before planting and during the summer. 5During summer, as new carabids emerged and insecticide toxicity declined, the presence of refuge strips influenced carabids in the adjacent crop area. Carabid activity density within crop areas previously treated with insecticide was significantly higher when adjacent to refuge strips. Also, carabid communities within insecticide-treated crop areas were affected by the presence or absence of a refuge strip. 6The presence of refuge strips did not consistently augment carabid numbers in crop areas where insecticide was not applied. One explanation may be that insecticides decreased the quality of crop habitat to carabids by depletion of prey and direct mortality. However, subsequent rebounds in prey density and the absence of competing predators may make these areas relatively more attractive than unperturbed crop habitats to carabid colonization from refuges. 7This study demonstrates that refuges may buffer the negative consequences of insecticide application on carabids in adjacent fields. Diversifying agro-ecosystems with refuge habitats may be a viable strategy for maintaining carabid populations in disturbed agricultural landscapes to keep pests below outbreak levels. [source] Modelling the interplay between pest movement and the physical design of trap crop systemsAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2005Salla Hannunen Abstract, 1,The interplay between pest movement and trap crop physical design is modelled in a situation where the pest moves by a random walk with spatially variable mobility. Questions addressed are: (i) how does the proportion of trap crop area of the total field area influence the equilibrium distribution of pests among the crop and the trap crop and (ii) how do crop patch size and shape influence the speed of pest redistribution from the crop to the trap crop. 2,When pest mobility in the trap crop is clearly lower than that in the crop, the pest population in the crop decreases very sharply for small trap crop proportions. When mobility in the trap crop is slightly closer to that in the crop, the pest population in the crop decreases much more gradually with increasing trap crop proportion. Thus finding a trap crop that the pest distinctly prefers over the crop appears to be crucial for developing efficient trap crop systems. 3,The rate of decay in the pest population in the crop increases with increasing perimeter to area ratio of the crop patch. Hence, designing field layouts to increase the perimeter to area ratio of crop patches may be beneficial. [source] Estimating Watershed Level Nonagricultural Pesticide Use From Golf Courses Using Geospatial Methods,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 6 2008Garey A. Fox Abstract:, Limited information exists on pesticide use for nonagricultural purposes, making it difficult to estimate pesticide loadings from nonagricultural sources to surface water and to conduct environmental risk assessments. A method was developed to estimate the amount of pesticide use on recreational turf grasses, specifically golf course turf grasses, for watersheds located throughout the conterminous United States (U.S.). The approach estimates pesticide use: (1) based on the area of recreational turf grasses (used as a surrogate for turf associated with golf courses) within the watershed, which was derived from maps of land cover, and (2) from data on the location and average treatable area of golf courses. The area of golf course turf grasses determined from these two methods was used to calculate the percentage of each watershed planted in golf course turf grass (percent crop area, or PCA). Turf-grass PCAs derived from the two methods were used with recommended application rates provided on pesticide labels to estimate total pesticide use on recreational turf within 1,606 watersheds associated with surface-water sources of drinking water. These pesticide use estimates made from label rates and PCAs were compared to use estimates from industry sales data on the amount of each pesticide sold for use within the watershed. The PCAs derived from the land-cover data had an average value of 0.4% of a watershed with minimum of 0.01% and a maximum of 9.8%, whereas the PCA values that are based on the number of golf courses in a watershed had an average of 0.3% of a watershed with a minimum of <0.01% and a maximum of 14.2%. Both the land-cover method and the number of golf courses method produced similar PCA distributions, suggesting that either technique may be used to provide a PCA estimate for recreational turf. The average and maximum PCAs generally correlated to watershed size, with the highest PCAs estimated for small watersheds. Using watershed specific PCAs, combined with label rates, resulted in greater than two orders of magnitude over-estimation of the pesticide use compared to estimates from sales data. [source] The release of genetically modified crops into the environmentTHE PLANT JOURNAL, Issue 1 2003Part I. Overview of current status, regulations Summary In the past 6 years, the global area of commercially grown, genetically modified (GM) crops has increased more than 30-fold to over 52 million hectares. The number of countries involved has more than doubled. Especially in developing countries, the GM crop area is anticipated to increase rapidly in the coming years. Despite this high adoption rate and future promises, there is a multitude of concerns about the impact of GM crops on the environment. Regulatory approaches in Europe and North America are essentially different. In the EU, it is based on the process of making GM crops; in the US, on the characteristics of the GM product. Many other countries are in the process of establishing regulation based on either system or a mixture. Despite these differences, the information required for risk assessment tends to be similar. Each risk assessment considers the possibility, probability and consequence of harm on a case-by-case basis. For GM crops, the impact of non-use should be added to this evaluation. It is important that the regulation of risk should not turn into the risk of regulation. The best and most appropriate baseline for comparison when performing risk assessment on GM crops is the impact of plants developed by traditional breeding. The latter is an integral and accepted part of agriculture. [source] Refuge habitats modify impact of insecticide disturbance on carabid beetle communitiesJOURNAL OF APPLIED ECOLOGY, Issue 2 2001Jana C. Lee Summary 1Carabid beetles are polyphagous predators that can act as biological control agents of insect pests and weeds. While current agricultural practices often create a harsh environment, habitat management such as the establishment of within-field refuges has been proposed to enhance carabid beetle abundance and impact. We examined the joint effects of refuge habitats and insecticide application on carabid activity density (parameter of population density and relative activity) and species composition in a cornfield. 2Our 2-year study comprised four treatments: (i) ,refuge/,insecticide; (ii) +refuge/,insecticide; (iii) ,refuge/+insecticide; (iv) +refuge/+insecticide. Refuge strips consisted of grasses, legumes and perennial flowering plants. ,,Refuge' strips were planted with corn and not treated with insecticide. 3Before planting and insecticide application, carabid activity density in the crop areas was similar across all treatments. Insecticide application immediately reduced carabid activity density and altered community composition in the crop area. 4Refuge strips had significantly higher activity density of beetles than ,refuge strips before planting and during the summer. 5During summer, as new carabids emerged and insecticide toxicity declined, the presence of refuge strips influenced carabids in the adjacent crop area. Carabid activity density within crop areas previously treated with insecticide was significantly higher when adjacent to refuge strips. Also, carabid communities within insecticide-treated crop areas were affected by the presence or absence of a refuge strip. 6The presence of refuge strips did not consistently augment carabid numbers in crop areas where insecticide was not applied. One explanation may be that insecticides decreased the quality of crop habitat to carabids by depletion of prey and direct mortality. However, subsequent rebounds in prey density and the absence of competing predators may make these areas relatively more attractive than unperturbed crop habitats to carabid colonization from refuges. 7This study demonstrates that refuges may buffer the negative consequences of insecticide application on carabids in adjacent fields. Diversifying agro-ecosystems with refuge habitats may be a viable strategy for maintaining carabid populations in disturbed agricultural landscapes to keep pests below outbreak levels. [source] Conservation biological control with the fungal pathogen Pandora neoaphidis: implications of aphid species, host plant and predator foragingAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2005S. Ekesi Abstract 1,Pandora neoaphidis is an important aphid-specific fungal pathogen in temperate agroecosystems. Laboratory studies were carried out to obtain baseline data on factors that may affect its performance in conservation biological control. 2,Virulence of P. neoaphidis was assessed in dose,response bioassays against Microlophium carnosum on nettle, Uroleucon jaceae on knapweed, Acyrthosiphon pisum on bean and bird's-foot trefoil Lotus corniculatus, and Metopolophium dirhodum on barley and Yorkshire fog Holcus lanatus. The most susceptible aphid was A. pisum feeding on bean with an LD50 of 19 conidia per mm2, whereas U. jaceae had an LD50 of 104 conidia per mm2 and was least susceptible to infection. 3,The presence of foraging adult ladybirds, Coccinella septempunctata, increased transmission of P. neoaphidis from infected cadavers to apterae of M. carnosum, U. jacea, and A. pisum by 7,30% at the largest cadaver density tested. Adult coccinellids that had previously foraged on nettle, knapweed, bean or bird's-foot trefoil transfered conidia to A. pisum on bean and induced infections in 2,13% of aphids. 4,Conidia of P. neoaphidis dispersed passively in the airstream from sporulating M. carnosum cadavers on nettle plants and initiated infections in A. pisum colonies feeding on bean (4,33%) or M. dirhodum on barley (3%) located within 1.0 m of the nettle source. 5,The results suggest that M. carnosum and A. pisum may be more useful as reservoirs for P. neoaphidis in noncrop and crop areas than U. jaceae or M. dirhodum, and infection and dispersal between habitats could be enhanced in the presence of coccinellids. [source] | ||||||||||