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41.
Guillermo Cabrera Walsh Anthony S. Dimeglio Ashot Khrimian Donald C. Weber 《Journal of pest science》2016,89(1):21-29
Harlequin bug (Murgantia histrionica) is an important pest of cole crops in the USA. The adults and nymphs feed on aboveground plant tissues by sucking cell contents and can seriously damage the host. Current insect control measures on cole crops target mainly lepidopteran pests, and the insecticides generally used do not control harlequin bug, so alternative management practices need to be explored. Previous research has established the existence of a male-produced pheromone attractive to both sexes and nymphs of M. histrionica. In this work, two systems of marking bugs were tested to verify if the mark affected fitness traits such as survival and host location. In a second phase, marked individuals were placed on trap host plants baited with synthetic pheromone lures to test whether migration rates were related to M. histrionica density on the trap plants and the presence of the attractants. Neither marking system affected the survival or orientation of the subjects compared to unmarked individuals. The pheromone lures significantly increased the attractiveness of the trap plants, but did not increase the retention time of the plants compared to unbaited plants. Emigration from the trap plants showed a constant rate and seemed unrelated to bug density on the plants. However, a mean peak density of ca. 36 bugs/plant was calculated. Beyond this number, density tended to decrease. These successful marking methods and retention time models support development of M. histrionica management with trap crops, by providing tentative control thresholds and decision rules. 相似文献
42.
Clement C.R. Weber J.C. van Leeuwen J. Astorga Domian C. Cole D.M. Arévalo Lopez L.A. Argüello H. 《Agroforestry Systems》2004,61(1-3):195-206
Agroforestry Systems - Peach palm (Bactris gasipaes) was domesticated as a fruit crop by the first Amazonians in traditional Neotropical agroforestry systems, but research and development... 相似文献
43.
E. Weber 《European Journal of Forest Research》1969,88(1):159-178
Zusammenfassung Im Jahre 1951 überwiegend durch gelenkte Kreuzung und teilweise aus freiem Abblühen entstandene L?rchen-Einzelbaumnachkommenschaften,
die zusammen mit einigen Bestandes-Nachkommenschaften im Versuchsgarten Grafrath erzogen und anschlie?end auf vier Versuchsfl?chen
innerhalb Bayerns angebaut worden waren, wurden zuletzt im zehn- bzw. achtj?hrigen Alter (in der Dickungsphase vor dem ersten
Pflegeeingriff) sowie im 16j?hrigen Alter (in der beginnenden Stangenholzphase nach dem ersten Eingriff) aufgenommen.
Auf Grund der aus diesen beiden Aufnahmen gewonnenen Ergebnisse (H?hen- und Durchmesser-Wuchsleistung, Variation der H?henwerte
vor dem ersten Eingriff, natürliche Ausf?lle, Schaftform, Astst?rke und Krebsbefall-H?ufigkeit) sind die verschiedenen Kombinationen
und Bestandes-Nachkommenschaften auf ihre Anbaubew?hrung hin überprüft worden:
Die Anbaubew?hrung kann unter Berücksichtigung der erfa?ten Merkmale für drei Kreuzungen voll bejaht werden, und zwar für
die Nummern 16 L. decidua 7/51×L. leptolepis (Gaut.), 20 L. decidua Kr. 1×L. leptolepis (Gaut.) und 10 Bastard 11/51×L. leptolepis
(Gaut.). Bei vier Nachkommenschaften (Nr. 5 L. leptolepis Kr. 4×L. decidua (Gaut.); Nr. 35 L. leptolepis-Bestandesnachk.;
Nr. 22 L. leptolepis 9/51×L. decidua 7/51 und Nr. 25 L. leptolepis 10/51×Bastard 1/51) mit überdurchschnittlicher Wüchsigkeit
darf das Ja zur Anbaubew?hrung wegen nicht voll überzeugenden Abschneidens in den übrigen Merkmalen nur mit gewisser Einschr?nkung
ausgesprochen werden.
Die Anbaubew?hrung mu? für drei Nachkommenschaften wegen Krebsbefalls und sehr geringer Wuchsleistung verneint werden; es
handelt sich dabei um die Nummern 4 L. lepteuropaea Kr. 2×L. decidua (Gaut.), 36 L. decidua-Bestandesnachkommenschaft und
20 L. decidua 7/51× freibest?ubt.
Die überwiegende Mehrzahl der angebauten L?rchen-Nachkommenschaften ist in eine breitangelegte Mittelgruppe mit nicht oder
nur sehr wenig differenziertem Wachstum inzuordnen, so da? erst die künftige Entwicklung die zu treffende Entscheidung erm?glichen
wird. 相似文献
44.
Hidden allergens are a common problem in food safety that has been known for many years. This is why the European Parliament adopted Directive 2003/89/EC amending 2000/13/EC. In addition to specific ingredients, Directive 2003/89/EC also requests the declaration of specific products that were used in the production and could be a risk for allergic individuals. This also includes the declaration of fining agents and lysozyme used in wines. In fact, it could be assumed that fining agents would be almost completely removed during the manufacturing process; however, until now there has been no necessity to analyze wine for these fining agents. By applying enzyme-linked immunosorbent assay (ELISA), residuals of fining agent proteins and the stabilizer lysozyme were investigated in various German wines. The results showed no detectable amounts of fining agents in wines, except for dried egg white and lysozyme, both derived from hen's egg white. For those products, adverse reactions against treated wines could not be excluded. 相似文献
45.
Brzozowski Lauren J. Weber Donald C. Wallingford Anna K. Mazourek Michael Agrawal Anurag A. 《Journal of pest science》2022,95(1):327-338
Journal of Pest Science - Co-occurring herbivorous pests may have shared or divergent responses to plant- and insect- derived cues, creating challenges for effective pest management in... 相似文献
46.
da Costa Eline Nayara Dantas de Souza Jéssica Carneiro Pereira Marilane Andrade de Souza Marcelo F. Landim de Souza Weber F. Landim da Silva Daniela Mariano Lopes 《Agroforestry Systems》2021,95(8):1647-1659
Agroforestry Systems - Inland waters such as streams that receive carbon from terrestrial landscapes usually have a net heterotrophic metabolism and emit significant amounts of CO2 to the... 相似文献
47.
T.A. Burns M.R. Watts P.S. Weber L.J. McCutcheon R.J. Geor J.K. Belknap 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(4):1280-1288
Background
In EMS‐associated laminitis, laminar failure may occur in response to energy failure related to insulin resistance (IR) or to the effect of hyperinsulinemia on laminar tissue. 5′‐Adenosine‐monophosphate‐activated protein kinase (AMPK) is a marker of tissue energy deprivation, which may occur in IR.Hypothesis/Objectives
To characterize tissue AMPK regulation in ponies subjected to a dietary carbohydrate (CHO) challenge.Animals
Twenty‐two mixed‐breed ponies.Methods
Immunohistochemistry and immunoblotting for total AMPK and phospho(P)‐AMPK and RT‐qPCR for AMPK‐responsive genes were performed on laminar, liver, and skeletal muscle samples collected after a 7‐day feeding protocol in which ponies stratified on body condition score (BCS; obese or lean) were fed either a low‐CHO diet (ESC + starch, approximately 7% DM; n = 5 obese, 5 lean) or a high‐CHO diet (ESC + starch, approximately 42% DM; n = 6 obese, 6 lean).Results
5′‐Adenosine‐monophosphate‐activated protein kinase was immunolocalized to laminar keratinocytes, dermal constituents, and hepatocytes. A high‐CHO diet resulted in significantly decreased laminar [P‐AMPK] in lean ponies (P = .03), but no changes in skeletal muscle (lean, P = .33; obese, P = .43) or liver (lean, P = .84; obese, P = .13) [P‐AMPK]. An inverse correlation existed between [blood glucose] and laminar [P‐AMPK] in obese ponies on a high‐CHO diet.Conclusions and Clinical Importance
Laminar tissue exhibited a normal response to a high‐CHO diet (decreased [P‐AMPK]), whereas this response was not observed in liver and skeletal muscle in both lean (skeletal muscle, P = .33; liver, P = .84) and obese (skeletal muscle, P = .43; liver, P = .13) ponies. 相似文献48.
R.M.G. Wells J. Baldwin R.S. Seymour R.E. Weber 《Fish physiology and biochemistry》1997,16(3):247-258
The oxygen binding properties of whole blood and hemoglobin were studied in three phylogenetically distant tropical teleosts inhabiting freshwater billabongs that exhibit marked seasonal oxygen stratification. The water breathing saratoga (Scleropages jardinii, Family Osteoglossidae), derived from an ancient divergence of the stem line leading to all other extant teleosts, has a low blood oxygen carrying capacity, Bohr and Root effect, and a high blood oxygen affinity. Erythrocytes contain a single major hemoglobin component, and equimolar concentrations of ATP and GTP. The tarpon (Megalops cyprinoides, Family Megalopidae), a facultative air-breather, has the highest blood oxygen carrying capacity and Bohr effect, and a low blood oxygen affinity and Root effect. Erythrocytes contain a single major hemoglobin and ATP as a putative regulator of hemoglobin oxygen affinity. Barramundi (Lates calcarifer, Family Centropomidae), is an obligate water-breather with intermediate blood oxygen binding properties, and the smallest Root effect. Erythrocytes contain at least 7 hemoglobins, and equimolar concentrations of ATP and GTP. Functional properties of these three blood oxygen transport systems are considered in terms of the respiratory environment and demand for oxygen. Our interpretation supports the hypothesis that the process of speciation can lead to divergence in physiological mechanisms, irrespective of past or present selection pressures. 相似文献
49.
Hemoglobin (Hb) multiplicity is a commonly used index of phylogenetic differentiation and molecular adaptation in fish. Despite
improvements in technologies for characterizing protein structure, our knowledge of the component composition of the Hb system
in rainbow trout, Oncorhychus mykiss, has remained almost unchanged through three decades. The Hb is considered to consist of four components, of which two (HbI
and HbIV) have been extensively characterised with regard to structure and function. Using a variety of molecular techniques
we demonstrate the presence of at least nine different Hb fractions composed of nine (five α and four β globin) chains, and
that HbI and HbIV consist of two and five individual components, respectively. These findings indicate that the published
data on trout HbI and HbIV refer to mixtures of isoHbs and need to be reappraised.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
50.