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1.
Habitat management under the auspices of conservation biological control is a widely used approach to foster conditions that ensure a diversity of predator species can persist spatially and temporally within agricultural landscapes in order to control their prey (pest) species. However, an emerging new factor, global climate change, has the potential to disrupt existing conservation biological control programs. Climate change may alter abiotic conditions such as temperature, precipitation, humidity and wind that in turn could alter the life-cycle timing of predator and prey species and the behavioral nature and strength of their interactions. Anticipating how climate change will affect predator and prey communities represents an important research challenge. We present a conceptual framework—the habitat domain concept—that is useful for understanding contingencies in the nature of predator diversity effects on prey based on predator and prey spatial movement in their habitat. We illustrate how this framework can be used to forecast whether biological control by predators will become more effective or become disrupted due to changing climate. We discuss how changes in predator–prey interactions are contingent on the tolerances of predators and prey species to changing abiotic conditions as determined by the degree of local adaptation and phenotypic plasticity exhibited by species populations. We conclude by discussing research approaches that are needed to help adjust conservation biological control management to deal with a climate future. 相似文献
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The production of maize, a major staple food crop in sub-Saharan Africa is being constrained by the parasitic weed Striga hermonthica. The fungus Fusarium oxysporum f. sp. strigae (Foxy 2) that causes fusarium wilt of Striga in Ghana, West Africa, is being considered for biological control of the weed in Western Kenya. The present study investigated the efficacy of F. oxysporum f. sp. strigae (Foxy 2) for S. hermonthica management in Western Kenya. Research was conducted in post-entry quarantine (PEQ) facilities at Alupe, Busia, Homabay, Kibos and Siaya field stations for two seasons. Each PEQ was a split-plot, with 4 main blocks each having 6 treatment subplots. The treatments included seeds of two S. hermonthica-susceptible maize varieties, either coated with Foxy 2 using gum Arabic, gum Arabic alone, or left untreated. Data was collected over seven sampling periods on S. hermonthica population per plant, percentage of those that were wilting, and the severity of wilting. Maize plant growth parameters assessed included duration to 50% anthesis and 50% silking, plant height, number of leaves, stover and cob weights, and maize yield per hectare. Statistical analysis was done using SAS 9.1 software. Data on S. hermonthica population were analyzed by χ2-test using Proc Genmod (Poisson); while the other parameters were analyzed by Proc Mixed using study location, season and blocks as random effects, and the sampling periods as repeated effects. All the assessed parameters were similar between plants grown from seeds inoculated with F. oxysporum f. sp. strigae (Foxy 2), those coated with gum Arabic, and the ones without any coating. These parameters were also not different between the maize varieties. There are varying reasons for the disparities between results on F. oxysporum f. sp. strigae (Foxy 2) obtained in this Kenyan study, and those from researches outside this country. In conclusion, F. oxysporum f. sp. strigae strain Foxy 2 is predominantly safe on maize growth, but its efficacy in controlling S. hermonthica was not evident on the tested Kenyan soils. 相似文献
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Parker Crutchfield 《Bioethics》2020,34(2):190-194
In a recent issue of Bioethics, I argued that compulsory moral bioenhancement should be administered covertly. Alexander Zambrano has criticized this argument on two fronts. First, contrary to my claim, Zambrano claims that the prevention of ultimate harm by covert moral bioenhancement fails to meet conditions for permissible liberty-restricting public health interventions. Second, contrary to my claim, Zambrano claims that covert moral bioenhancement undermines autonomy to a greater degree than does overt moral bioenhancement. In this paper, I rebut both of these arguments, then finish by noting important avenues of research that Zambrano’s arguments motivate. 相似文献
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Emiru Seyoum Wojciech J. Pulawski 《Archives Of Phytopathology And Plant Protection》2013,46(5):319-326
The possibility of using sphecid wasps to control acridid pests is discussed. A list of 19 Ethiopian species that could be utilized for this purpose is provided. 相似文献
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频振式杀虫灯在茶树害虫测报、防治中的应用 总被引:7,自引:0,他引:7
应用佳多频振式杀虫灯进行了茶树害虫的预测预报和防治试验。结果表明,该灯对茶园中的茶细蛾Caloptiliatheivora(walsingham)、茶毛虫EuproctispseudoconspersaStrand、斜纹夜蛾Prodenialitura(Fabricius)等茶树主要害虫有明显的诱集作用;同时,根据害虫成虫诱集时间、数量与面上生育期观察,其动态变化基本一致,可以用于幼虫的发生期、发生量预报,在面上应用频振式杀虫灯对3种的防治试验中取得明显的效果。认为该灯是一种安全、经济、有效、无污染的茶树害虫预测预报和防治工具。 相似文献
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Development of a sequence-specific real-time PCR to the melon thrips Thrips palmi (Thysan., Thripidae) 总被引:1,自引:0,他引:1
Abstract: In recent years, the polyphagous pest Thrips palmi Karny has become a species of major quarantine concern, often intercepted on plant material in international trade. The ability to rapidly identify the species is a critical factor that will determine the success of any campaign to prevent its establishment in Europe or elsewhere. However, the immature stages cannot currently be identified to the species level with certainty by morphological methods. In this study, random amplified polymorphic DNA analysis was performed to identify putative markers, which were then screened by Southern blot analysis. One marker was sequenced and a real-time polymerase chain reaction assay developed. The assay was screened against 21 thrips species including 10 other species of the genus Thrips and were found to be specific to T. palmi . The assay is rapid, could be completed in as little as 45 min and can be used to aid the identification of T. palmi . 相似文献