Novel mechanism of thrips suppression by Cry51Aa2.834_16 Bt toxin expressed in cotton     

Anders S Huseth  Damon A D&#x;Ambrosio  Benjamin T Yorke  Graham P Head  George G Kennedy 《Pest management science》2020,76(4):1492-1499

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Climate‐based seasonal dynamics of the invasive red palm mite Raoiella indica     

Ricardo Siqueira da Silva  Elisngela Gomes Fidelis  George Amaro  Rodrigo Soares Ramos  Paulo Antnio Santana Junior  Marcelo Coutinho Picano 《Pest management science》2020,76(11):3849-3856

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Climate variability and marine survival of coho salmon (Oncorhynchus kisutch) in the Oregon production area   总被引：1，自引：0，他引：1  

J. Anthony Koslow  Alistair J. Hobday  & George W. Boehlert 《Fisheries Oceanography》2002,11(2):65-77

Time series of adult recruitment for natural runs of coho salmon from the Oregon coastal region (1970–94) and marine survival of hatchery-reared coho salmon from California to Washington (1960–94) are significantly correlated with a suite of meteorological and oceanographic variables related to the biological productivity of the local coastal region. These variables include strong upwelling, cool sea surface temperature (SST), strong wind mixing, a deep and weakly stratified mixed layer, and low coastal sea level, indicating strong transport of the California Current. Principal component analysis indicates that these variables work in concert to define the dominant modes of physical variability, which appear to regulate nutrient availability and biological productivity. Multiple regression analysis suggests that coho marine survival is significantly and independently related to the dominant modes acting over this region in the periods when the coho first enter the ocean and during the overwintering/spring period prior to their spawning migration. Linear relationships provided good fits to the data and were robust, capable of predicting randomly removed portions of the data set.  相似文献   

Model uncertainty in the ecosystem approach to fisheries   总被引：2，自引：0，他引：2  

Simeon L. Hill  George M. Watters  ré E. Punt  Murdoch K. McAllister  Corinne Le Quéré  John Turner 《Fish and Fisheries》2007,8(4):315-336

Fisheries scientists habitually consider uncertainty in parameter values, but often neglect uncertainty about model structure, an issue of increasing importance as ecosystem models are devised to support the move to an ecosystem approach to fisheries (EAF). This paper sets out pragmatic approaches with which to account for uncertainties in model structure and we review current ways of dealing with this issue in fisheries and other disciplines. All involve considering a set of alternative models representing different structural assumptions, but differ in how those models are used. The models can be asked to identify bounds on possible outcomes, find management actions that will perform adequately irrespective of the true model, find management actions that best achieve one or more objectives given weights assigned to each model, or formalize hypotheses for evaluation through experimentation. Data availability is likely to limit the use of approaches that involve weighting alternative models in an ecosystem setting, and the cost of experimentation is likely to limit its use. Practical implementation of an EAF should therefore be based on management approaches that acknowledge the uncertainty inherent in model predictions and are robust to it. Model results must be presented in ways that represent the risks and trade‐offs associated with alternative actions and the degree of uncertainty in predictions. This presentation should not disguise the fact that, in many cases, estimates of model uncertainty may be based on subjective criteria. The problem of model uncertainty is far from unique to fisheries, and a dialogue among fisheries modellers and modellers from other scientific communities will therefore be helpful.  相似文献   

Hamlin county seed treatment survey     

George H. Valentine 《American Journal of Potato Research》1926,3(3):92-93

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The potato situation     

F. Jensen  J. M. Hurley  Walter M. Peacock  Julian A. Dimock  J. B. R. Dickey  J. W. Weston  Geo W. Musgrave  E. V. Hardenburg  George H. Valentine  Wm. H. Martin 《American Journal of Potato Research》1925,2(4):133-174

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Potato notes     

J. T. Rosa  E. A. Stokdyk  H. J. Wheeler  J. F. Hockey  H. O. Werner  W. H. Martin  O. G. Bowen  J. Gilbert Barton  Wm. B. Duryee  J. C. Crissey  A. H. C. Odell  C. R. Inglee  Julian A. Dimock  H. H. Zimmerly  George L. Zundel 《American Journal of Potato Research》1924,1(8):143-151

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Protective and defensive roles of non-glandular trichomes against multiple stresses:structure-function coordination     

George Karabourniotis  Georgios Liakopoulos  Dimosthenis Nikolopoulos  Panagiota Bresta 《林业研究》2020,31(1):1-12

As superficial structures,non-glandular trichomes,protect plant organs against multiple biotic and abiotic stresses.The protective and defensive roles of these epidermal appendages are crucial to developing organs and can be attributed to the excellent combination of suitable structural traits and chemical reinforcement in the form of phenolic compounds,primarily fl avonoids.Both the formation of trichomes and the accumulation of phenolics are interrelated at the molecular level.During the early stages of development,non-glandular trichomes show strong morphological similarities to glandular ones such as the balloon-like apical cells with numerous phenolics.At later developmental stages,and during secondary wall thickening,phenolics are transferred to the cell walls of the trichomes.Due to the diff use deposition of phenolics in the cell walls,trichomes provide protection against UV-B radiation by behaving as optical fi lters,screening out wavelengths that could damage sensitive tissues.Protection from strong visible radiation is also aff orded by increased surface light refl ectance.Moreover,the mixtures of trichome phenolics represent a superfi-cial chemical barrier that provides protection against biotic stress factors such as herbivores and pathogens.Although the cells of some trichomes die at maturity,they can modulate their quantitative and qualitative characteristics during development,depending on the prevailing conditions of the external biotic or abiotic environment.In fact,the structure and chemical constituents of trichomes may change due to the particular light regime,herbivore damage,wounding,water stress,salinity and the presence of heavy metals.Hence,trichomes represent dynamic protective structures that may greatly aff ect the outcome of many plant–environment interactions.  相似文献   

Nutrients in litterfall,forest floor and mineral soils in two adjacent forest ecosystems in Greece     

Panagiotis Michopoulos  Kostas Kaoukis  George Karetsos  Theodoros Grigoratos  Constantini Samara 《林业研究》2020,31(1):291-301

The fluxes of masses and the nutrients Ca,Mg,K,N,P and S were determined in the litterfall of two adjacent forest ecosystems of Hungarian oak(Quercus frainetto L.)and European beech(Fagus sylvatica L.)in a mountainous area of northeastern Greece in 2010–2015.The foliar litterfall for both species reached about 70%of the total litterfall,and was significantly higher from the other two fractions(woody and rest litterfall).The fluxes of masses and nutrients were compared between ecosystems for each fraction separately.Only one significant statistical difference was found,that of K in the woody litterfall.In addition,the stocks of masses and nutrients were calculated in the forest floors and mineral soils of the two ecosystems.Likewise,the stocks of nutrients in the forest floors and mineral soils were compared between ecosystems.In the L horizon of the forest floors,statistical differences,as a result of species effect,were found for the stocks of Ca and N.In the FH horizons,the masses and all the nutrient stocks differed significantly,as the beech plot had much higher quantities of organic matter and nutrients.These higher quantities were probably due to low soil temperatures(microclimate)and high acidity in the beech plot(species effect)that slowed down decomposition.In the mineral soils,the propagation of random error derived from random errors of the individual soil layers was an important factor in the statistical comparisons.Because of the soil acidity in the beech plot,the stocks of exchangeable base cations were significantly higher in the oak plot,whereas the other nutrient stocks did not differ.  相似文献   

The United States energy dilemma: How can we solve it?     

Hill  George R. 《Water, air, and soil pollution》1977,7(2):141-146

Water, Air, & Soil Pollution - The basis for the present energy dilemma is described. The current solution to the inadequate petroleum and natural gas supplies and possible long-term solutions...  相似文献