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Diana W. Bianchi Tim Van Mieghem Lisa G. Shaffer Brigitte H. W. Faas Lyn S. Chitty Alessandro Ghidini Jan Deprest 《黑龙江环境通报》2014,34(1):1-5
本文提出怎样理解产学研相结合的问题,并从产学研不同层面进行分析,提出以市场为目标、以制度为保证实现产学研有效结合的思路。 相似文献
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Plant volatile cues are considered the main source of information for ovipositing moths, which use chemical information to
locate and recognize the host plant. In Europe, two sympatric populations of European corn borer (ECB; Ostrinia nubilalis, Hübner), the Z and E-pheromone races, feed mainly on maize and hop or mugwort, respectively. We studied the mechanisms of
host-plant recognition and fidelity in ECB pheromone races by testing the attractiveness of host plants to gravid females
in a flight tunnel and by analyzing the volatiles released from maize, mugwort, and hop during the scotophase, when the ovipositing
flight of the ECB females occurs. In the wind tunnel bioassay, the Z-race and E-race females engaged in upwind flight and
expressed a strong host fidelity to their respective main host plants; all three of these host plants possess distinctive
volatile profiles specific as to blend and ratio. The host plants shared a certain number of ubiquitous volatiles present
in various ratios that likely constitute a species-specific cue to host-seeking ECB moths. Our observations therefore suggest
that ECB host fidelity is steered by plant volatiles that are present in species-specific ratios of ubiquitous volatile organic
compounds. 相似文献
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Sandra A. Bryce David P Larsen Robert M. Hughes Philip R. Kaufmann 《Journal of the American Water Resources Association》1999,35(1):23-36
ABSTRACT: Aquatic monitoring aims to assess the condition of aquatic habitats and biota. To make statements about condition, the range of human activities and the risks they pose to aquatic ecosystems must be identified. Assessing relative risk and placing sample sites on a human disturbance gradient is necessary for interpreting biological response and distinguishing human disturbance from natural controls in aquatic systems. We describe a process that uses readily available sources, such as topographic maps, aerial photographs, and field information, to identify and prioritize stream reach and watershed stressors for 102 streams in the mid-Appalachian region of the United States. All perceptible human alterations to riparian and upland areas along with their number, type, intensity, and extent of impact were recorded and ranked; a relative risk index was developed to assign scores to the watersheds. The resulting risk index scores were consistent with measures of stream condition based on water chemistry and benthic macroinvertebrates. The risk index gives a cost-effective, regional picture of the relative risk of impairment to aquatic ecosystems in the mid-Appalachian region of the USA and could be modified for other regions or ecosystem types. 相似文献
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Most crop pests find a suitable host through chemical cues released from plants, but little is known about the odorscape encountered by host-seeking gravid females under natural, outdoor conditions. In this field study, the volatile organic compound (VOC) composition of maize (Zea mays, L.), a host for the European corn borer (ECB) (Ostrinia nubilalis Hüb.) was characterized during the oviposition flight and compared with a forest odorscape. VOCs from maize fields and the forest atmosphere were collected by solid phase microextraction and characterized by gas chromatography-mass spectrometry. The electroantennographic (EAG) response of female ECB antennae to candidate VOCs was tested. Analyses revealed clear differences between the maize field and the forest odorscapes, mainly composed of ubiquitous VOCs but in specific ratios. The maize field odorscape is more complex than the forest odorscape for maize found 18 VOCs but only eight in the forest. Both biotopes shared seven VOCs—green leaf volatiles (GLV), monoterpènes (MT) and homoterpenes. In addition, we found in the forest a distinctive sesquiterpene (SQT) identified as isoledene. The highest EAG responses were elicited by two GLVs and a MT shared by the two biotopes. SQT elicited weak EAG responses, except β-farnesene, only found in the maize field odorscape. Our results suggest that the two biotopes produce specific chemical signatures that insects may use as host cues. To the best of our knowledge this paper is the first report on the maize odorscapes under field conditions. The putative role of the VOCs in host plant detection and selection is discussed. 相似文献
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