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71.
The use of a selective insecticide is highly recommended for Integrated Pest Management programs. Plenum (a.i.: pymetrozine;
Syngenta Agro), a systemic insecticide, is regarded as a good candidate for use in situations where plant-sucking insects
have to be controlled and where natural enemies can play a substantial role as biological control agents. In this context,
the effects of Plenum on a host–endoparasitoid relationship were investigated. Potato aphids Macrosiphum euphorbiae were reared for 4 days on an artificial diet supplemented with a low concentration of Plenum (sublethal concentration inducing
15% aphid mortality) before parasitization by the endoparasitoid Aphidius ervi. The development of A. ervi larvae was negatively affected, especially during the early stages of development, and the sex ratio of the progeny was strongly
male-biased. Moreover, the host-choice experiment showed that A. ervi was not able to discriminate between control and Plenum-contaminated aphids. These results show that Plenum may not be as
selective as it was previously thought to be, and the observed effects need to be considered when developing IPM systems. 相似文献
72.
Response of sediment biofilm to increased dissolved organic carbon supply in groundwater artificially recharged with stormwater 总被引:1,自引:0,他引:1
Arnaud Foulquier Florian Mermillod-Blondin Florian Malard Janine Gibert 《Journal of Soils and Sediments》2011,11(2):382-393
Purpose
Best management practices encompass diverse artificial groundwater recharge (AGR) systems that heavily rely upon the capacity of the soil and vadose zone to retain large quantities of organic matter generated during stormwater runoff on urban catchments. However, the supply of stormwater-derived dissolved organic carbon (DOC) at the water-table region of aquifers can enhance the rate of biogeochemical processes by fueling heterotrophic microbial metabolism. This study examined changes in the abundance and activity of sediment biofilm in response to increased DOC supply at the water table of an urban aquifer intentionally recharged with stormwater. Changes in microbial abundance and activity under field conditions were compared with those measured in laboratory slow filtration columns supplied with an easily biodegradable source of DOC. 相似文献73.
Serum parathyroid hormone in X-linked hypophosphatemia 总被引:6,自引:0,他引:6
Serum immunoreactive parathyroid hormone(IPTH) is normal in patients with X-linked hypophosphatemic rickets who are not treated with phosphate salts. Phosphate raises IPTH in these patients. Endogenous IPTH does not influence the existing defect in tubular reabsorption of phosphate in male patients. 相似文献
74.
The global atmospheric circulation on moist isentropes 总被引:1,自引:0,他引:1
The global atmospheric circulation transports energy from the equatorial regions to higher latitudes through a poleward flow of high-energy and -entropy parcels and an equatorward flow of air with lower energy and entropy content. Because of its turbulent nature, this circulation can only be described in some averaged sense. Here, we show that the total mass transport by the circulation is twice as large when averaged on moist isentropes than when averaged on dry isentropes. The additional mass transport on moist isentropes corresponds to a poleward flow of warm moist air near Earth's surface that rises into the upper troposphere within mid-latitudes and accounts for up to half of the air in the upper troposphere in polar regions. 相似文献
75.
Miller N Estoup A Toepfer S Bourguet D Lapchin L Derridj S Kim KS Reynaud P Furlan L Guillemaud T 《Science (New York, N.Y.)》2005,310(5750):992
The invasion of Europe by the western corn rootworm, North America's most destructive corn pest, is ongoing and represents a serious threat to European agriculture. Because this pest was initially introduced in Central Europe, it was believed that subsequent outbreaks in Western Europe originated from this area. Using model-based Bayesian analyses of the genetic variability of the western corn rootworm, we demonstrate that this belief is false: There have been at least three independent introductions from North America during the past two decades. This result raises questions about changing circumstances that have enabled a sudden burst of transatlantic introductions. 相似文献
76.
77.
Host genetic resistance to root‐knot nematodes,Meloidogyne spp., in Solanaceae: from genes to the field
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Arnaud Barbary Caroline Djian‐Caporalino Alain Palloix Philippe Castagnone‐Sereno 《Pest management science》2015,71(12):1591-1598
Root‐knot nematodes (RKNs) heavily damage most solanaceous crops worldwide. Fortunately, major resistance genes are available in a number of plant species, and their use provides a safe and economically relevant strategy for RKN control. From a structural point of view, these genes often harbour NBS–LRR motifs (i.e. a nucleotide binding site and a leucine rich repeat region near the carboxy terminus) and are organised in syntenic clusters in solanaceous genomes. Their introgression from wild to cultivated plants remains a challenge for breeders, although facilitated by marker‐assisted selection. As shown with other pathosystems, the genetic background into which the resistance genes are introgressed is of prime importance to both the expression of the resistance and its durability, as exemplified by the recent discovery of quantitative trait loci conferring quantitative resistance to RKNs in pepper. The deployment of resistance genes at a large scale may result in the emergence and spread of virulent nematode populations able to overcome them, as already reported in tomato and pepper. Therefore, careful management of the resistance genes available in solanaceous crops is crucial to avoid significant reduction in the duration of RKN genetic control in the field. From that perspective, only rational management combining breeding and cultivation practices will allow the design and implementation of innovative, sustainable crop production systems that protect the resistance genes and maintain their durability. © 2015 Society of Chemical Industry 相似文献
78.
Biological characteristics of the hydrological landscapes in the Bay of Biscay in spring 2009
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Ainhoa Lezama‐Ochoa Daniel Grados Anne Lebourges‐Dhaussy Xabier Irigoien Alexis Chaigneau Arnaud Bertrand 《Fisheries Oceanography》2015,24(1):26-41
In the present study we investigated the biogeography of macrozooplankton and fish biomass in the Bay of Biscay. In this region, we defined six different landscapes based on the hydrogeographical characteristics observed in spring 2009. We then related landscape's characteristics and environmental parameters such as light attenuation depth and chlorophyll‐a with macrozooplankton and fish acoustic biomass. Hydrodynamic structures together with coastal influences (river discharges, predation pressure and depth preference) and vertical thermohaline structure/mixing (feeding modes and ability to stay in preferred layers) appeared as the main factors determining the biological distribution. Besides, variance partitioning was used to assess the respective roles played by the hydrological environment, the geographical space and the biological environment alone, and their interactions. Results revealed that: (i) macrozooplankton and fish have a preference for different hydrogeographical landscapes; (ii) the association between hydrological conditions and geographical features, i.e. the spatial structure of the hydrological environment, plays a key role in the distribution of macrozooplankton; and (iii) prey–predator relationships have to be taken into account to provide a comprehensive characterization of habitat suitability. 相似文献
79.
80.