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61.
Andrea Maiorano Amedeo Reyneri Dario Sacco Aronne Magni Cesare Ramponi 《Crop Protection》2009,28(3):243-256
Fumonisin contamination of maize grain starts in the field. Forecasting Fusarium infection and fumonisin synthesis could allow operators in the field to control contamination during the growing season and to make the best agronomic decisions for high quality yields while respecting the limits imposed by the European Union.A research project to develop a decision support system for the control of field-phase fumonisin contamination began in Italy in 2003. This paper presents a preliminary version of the engine of the decision support tool: FUMAgrain, a dynamic risk assessment model developed with data from the north of Italy. The structure of FUMAgrain is based on the pathosystem formed by maize, F. verticillioides and Ostrinia nubilalis (European Corn Borer). The elements of the pathosystem are simulated by three sub-models: (i) maize development, (ii) F. verticillioides infection and fumonisin synthesis, (iii) European Corn Borer wounding activity on maize grain. Inputs to the model are (i) planting date, (ii) hourly meteorological data including temperature, relative humidity, wind speed and rain intensity, (iii) information on the phenological development of the hybrid planted (flowering and dry-down), and (iv) information about the chemical treatment against European Corn Borer. FUMAgrain gives an initial risk alert at the end of flowering based on the meteorological conditions during this phase. A second alert follows maturation when an assessment is made from (i) maize grain moisture, (ii) European Corn Borer damage to the ear, and (iii) fumonisin synthesis risk. Following calibration and validation with data FUMAgrain demonstrated its good capability to simulate fumonisin synthesis in maize grain in Italy (calibration: R2 = 0.70; validation: R2 = 0.71) and its usefulness for determining the optimal harvest date while respecting grain safety levels required by the international market and limiting moisture content, hence drying costs. 相似文献
62.
The present report is part of a study of the development and distribution of blood vessels in the skin of various domestic animals. Twenty-six newborn pigs were injected with a mixture of equal parts of India ink and bovine serum. The fixed skin was dehydrated and cleared. The formation and pattern of the cutaneous arterial networks and venous plexuses were studied. 相似文献
63.
Andrea J. Fascetti Glenna E. Mauldin DVM MS G. Neal Mauldin 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(1):9-13
There are no available biochemical analyses that will reliably identify malnourished cats or enable monitoring them during supportive alimentation. Studies in people indicate that creatine kinase (CK) activity is high in malnourished patients and may decrease in response to nutritional intervention. The purpose of this study was to determine the value of quantifying serum CK activities in anorectic cats and to assess the usefulness of this test in monitoring nutritional support in these patients. Serum CK activity was evaluated in nonanorectic cats (Group 1, n = 25), and in hospitalized, anorectic cats that received nutritional support through a nasoesophageal tube (Group 2, n = 25). Anorectic cats had a significantly higher serum CK activity (median = 2,529 U/L, range 88 to 153,000 U/L) than the control group (median = 175 U/L, range 81 to 363 U/L, P < .001). There were significant positive correlations between serum CK and both aspartate transaminase (AST) ( P < .05; r = .59) and lactate dehydrogenase (LDH) (P < .05; r = .41) activities. Serum CK activity was significantly lower in anorectic cats after 48 hours of nutritional support than at time 0 ( P < .001) and eventually returned to normal with continued support. Serum CK activity may serve as a useful marker in assessing and monitoring nutritional status in cats. 相似文献
64.
Balboni Andrea Terrusi Alessia Urbani Lorenza Troia Roberta Stefanelli Silvia A. M. Giunti Massimo Battilani Mara 《Veterinary research communications》2022,46(1):223-232
Veterinary Research Communications - Canine parvovirus type 2 (CPV-2) is one of the most relevant pathogens associated with enteritis in dogs and is frequently reported in association with the... 相似文献
65.
66.
Dr. R. Plarre Maja Pöschko Sabine Prozell Andrea Frank R. Wohlgemuth J. K. Phillips 《Journal of pest science》1997,70(3):45-50
Tineola bisselliella is a common pest on natural fabrics of economic importance. Two commercially available repellents for use against adult webbing clothes moths were tested for their efficacy in dual- and no-choice bioassays. Oil of cloves and citral in combination, as well as citronellol scented with oil of lavender showed promising repellent effects for 4 weeks when applied in small compartments of a wardrobe. Although the repellent efficacy was not 100% under the conditions tested, the usage of essential oils in combination with other infestation prevention techniques is discussed.
This article reports the results of research only. Mention of a proprietary product or pesticide does not constitute an endorsement or a recommendation for its use by the Federal Biological Research Centre for Agriculture and Forestry or by the USDA-ARS. 相似文献
Zusammenfassung Die KleidermotteTineola bisselliella Hum. ist einer der wirtschaftlich bedeutenden tierischen Wollzerstörer. Auch Pelze, Felle, Polsterhaare und Federn werden von dem weit verbreiteten Kleinschmetterling aus der Familie der Tineidae befallen. In der Praxis gilt es vor allem Kleidungsstücke, die z. B. saisonbedingt für längere Zeit ungenutzt in einem Kleiderschrank aufbewahrt werden, vor dem Befall durch die Kleidermotte zu schützen. Hierfür stehen dem Verbraucher neben den konventionellen Bekämpfungsmitteln mit den Wirkstoffen Kampfer, Naphthalin und Paradichlorbenzol sowie pyrethrum- und pyrethroidhaltige Mittel auch Präparate zur Verfügung, die auf die repellierende Wirkung von ätherischen Ölen zurückgreifen. Die abstoßende Wirkung von Nelkenöl in Kombination mit Citral und von Citronellol parfümiert mit Lavendelöl auf die Falter der Kleidermotte wurde auf vergleichbare Eigenschaften untersucht. In Wahlversuchen wurden deutliche Repellent-Wirkungen der Mottenschutz-Präparate sichtbar. Die Präparate zeigten gute Wirkungen, wenn sie zum Schutz gegen den Zuflug von Kleidermotten an wollhaltigen Stoffen in kleinen Kompartimenten eines Kleiderschrankes ausgelegt waren. Auch in Zwangsversuchen hatte dieser Befund zum Teil Bestand. Bei längeren Versuchszeiten wurden allerdings verstärkt Fraßschäden durch Larven an den Wollstoffen festgestellt. Dies ist darauf zurückzuführen, daß Mottenweibchen nicht mehr in dem Maße repelliert wurden und ihre Eier an den Stoffen ablegten.
This article reports the results of research only. Mention of a proprietary product or pesticide does not constitute an endorsement or a recommendation for its use by the Federal Biological Research Centre for Agriculture and Forestry or by the USDA-ARS. 相似文献
67.
U. Ammer G. Einsele W. Arnold O. Klee R. Agerer G. Agster U. Babel J. Behringer W. Böcking F. -H. Evers W. Fleck H. Günzl K. -F. Hofmann H. Janz J. Körner I. Kottke V. Kracht A. Krebs K. Kunzweiler W. -D. Langbein H. -U. Moosmauer S. Müller E. Nickel S. Pfeiffer R. Rausch H. Schmidt-Witte O. Schwarz R. Stegmayer 《European Journal of Forest Research》1983,102(1):282-324
Ohne Zusammenfassung
(Prof. Agerer seit 1982 am Institut für Systematische Botanik, München).
(Weilimdorf)
(zuvor t?tig bei der FVA Stuttgart, siehe oben)
(Hohenheim) 相似文献
68.
Summary The aim of the present study was to investigate whether the resistance of beech foliage(Fagus sylvatica) against oxidative stress was affected by soil quality, nitrogen or CO2 fertilisation, or lachnid infestation(Phyllaphis fagi). For this purpose young beech trees were grown for four years in reconstructed calcareous or acidic forest soils in open
top chambers under ambient or elevated CO2 concentrations with two levels of nitrogen fertilisation. At harvest lachnid colonisation was observed, preferentially on
leaves from trees in calcareous soil and on leaves from trees fertilised with the high nitrogen level. General leaf characteristics
such as pigment concentrations, dry mass, and leaf mass ber area were not affected by the soil type, nitrogen fertilisation
or CO2 regime. Leaves colonised with lachnids displayed slightly increased leaf mass per area. When the stress resistance was challenged
by exposure to paraquat — a herbicide inducing oxidative stress — leaves from trees grown on calcareous soil maintained significantly
longer membrane integrity and, thus, were better protected against stress than leaves from trees on acidic soil. Other experimental
variables had negligible or no effects on the resistance against oxidative stress.
相似文献
69.
As forests age, their structure and productivity change, yet in some cases, annual rates of water loss remain unchanged. To identify mechanisms that might explain such observations, and to determine if widely different age classes of forests differ functionally, we examined young (Y, approximately 25 years), mature (M, approximately 90 years) and old (O, approximately 250 years) ponderosa pine (Pinus ponderosa Dougl. ex P. Laws.) stands growing in a drought-prone region of central Oregon. Although the stands differed in tree leaf area index (LAIT) (Y = 0.9, M = 2.8, O = 2.1), cumulative tree transpiration measured by sap flow did not differ substantially during the growing season (100-112 mm). Yet when water was readily available, transpiration per unit leaf area of the youngest trees was about three times that of M trees and five times that of O trees. These patterns resulted from a nearly sixfold difference in leaf specific conductance (KL) between the youngest and oldest trees. At the time of maximum transpiration in the Y stand in May-June, gross carbon uptake (gross ecosystem production, GEP) was similar for Y and O stands despite an almost twofold difference in stand leaf area index (LAIS). However, the higher rate of water use by Y trees was not sustainable in the drought-prone environment, and between spring and late summer, KL of Y trees declined fivefold compared with a nearly twofold decline for M trees and a < 30% reduction in O trees. Because the Y stand contained a significant shrub understory and more exposed soil, there was no appreciable difference in mean daily latent energy fluxes between the Y stand and the older stands as measured by the eddy-covariance technique. These patterns resulted in 60 to 85% higher seasonal GEP and 55 to 65% higher water-use efficiency at the M and O stands compared with the Y stand. 相似文献
70.