132 research outputs found
The Mississippi River System Shallow Draft Barge Market – Perfectly Competitive or Oligopolistic?
Most transportation textbooks and articles on inland waterway navigation assume a perfectly competitive Mississippi River system barge industry. One study found the 1972 and 1977 grain barge industry to be oligopolistic. A second study of the U.S. barge industry found "intra industry competition for the barge industry on a day-to-day basis with easy entry and exit." Using the concentration ratio and the Herfindahl Index, this study found the Mississippi River barge industry to be oligopolistic. These results suggest that Mississippi River navigation infrastructure studies should not use long run marginal barge costs as a proxy for barge rates
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Impact of floral feeding on adult Drosophila suzukii survival and nutrient status
Drosophila suzukii, spotted wing drosophila, is a serious pest of small fruits and cherries in many regions of the world. While host usage has been well studied at the ovipositional and larval feeding stages, little is known about the feeding ecology and nutrient requirements of adults. This study addressed the impact of feeding on the survival and nutrient reserves of adult D. suzukii in laboratory assays. First, access to cherry blossoms increased survival rates of both adult males and females compared to water only. This suggests that these early spring blossoms may provide a food source for D. suzukii in fields that may be devoid of other food sources. Second, D. suzukii reared on a standard laboratory diet as larvae emerged as adults with minimal glycogen and sugar levels. Adults with continued access to a carbohydrate–protein diet showed rapidly elevated carbohydrate reserves, and adults with continued access to only water showed a decline in total sugars. Third, females with access to cherry or blueberry blossoms showed elevated carbohydrate reserves when compared to those with access to water only. These results illustrate the importance of adult feeding in enhancing survival and carbohydrate reserves among D. suzukii.To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf, displayed as an "Author's personal copy." The published article is copyrighted by Springer and can be found at: https://doi.org/10.1007/s10340-016-0762-
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Impact of floral feeding on adult Drosophila suzukii survival and nutrient status
Drosophila suzukii, spotted wing drosophila, is a serious pest of small fruits and cherries in many regions of the world. While host usage has been well studied at the ovipositional and larval feeding stages, little is known about the feeding ecology and nutrient requirements of adults. This study addressed the impact of feeding on the survival and nutrient reserves of adult D. suzukii in laboratory assays. First, access to cherry blossoms increased survival rates of both adult males and females compared to water only. This suggests that these early spring blossoms may provide a food source for D. suzukii in fields that may be devoid of other food sources. Second, D. suzukii reared on a standard laboratory diet as larvae emerged as adults with minimal glycogen and sugar levels. Adults with continued access to a carbohydrate–protein diet showed rapidly elevated carbohydrate reserves, and adults with continued access to only water showed a decline in total sugars. Third, females with access to cherry or blueberry blossoms showed elevated carbohydrate reserves when compared to those with access to water only. These results illustrate the importance of adult feeding in enhancing survival and carbohydrate reserves among D. suzukii.This is the publisher’s final pdf. The published article is copyrighted by Springer Verlag and can be found at: http://link.springer.com/article/10.1007%2Fs10340-016-0762-7Keywords: Sugar, Lipid, Nectar, Glycoge
Seasonal cues induce phenotypic plasticity of Drosophila suzukii to enhance winter survival
Additional file 7: Table S6. Table of differentially expressed genes in bodies of winter morphs of D. suzukii relative to those of summer morphs. Fold change represents the ratio of expression levels of winter to summer morphs
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Effects of Six Vineyard Fungicides on the Juvenile Predatory Mite Typhlodromus Pyri
Genome of Drosophila suzukii, the spotted wing drosophila.
Drosophila suzukii Matsumura (spotted wing drosophila) has recently become a serious pest of a wide variety of fruit crops in the United States as well as in Europe, leading to substantial yearly crop losses. To enable basic and applied research of this important pest, we sequenced the D. suzukii genome to obtain a high-quality reference sequence. Here, we discuss the basic properties of the genome and transcriptome and describe patterns of genome evolution in D. suzukii and its close relatives. Our analyses and genome annotations are presented in a web portal, SpottedWingFlyBase, to facilitate public access
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Trapping and identifying mealybugs in Oregon vineyards
Mealybugs, a family of soft, oval-bodied pests (Homoptera: Pseudococcidae), are known vectors (carriers) of the grapevine leafroll associated viruses (GLRaVs) of grape. This document gives details on how pheromone traps should be used to ensure optimal catches and early detection.Published January 2010. Reviewed January 2015. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogKeywords: pests, grapes, vineyards, mealybug
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Hazelnut : 2017 pest management guide for the Willamette Valley
Revised April 2017.
Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
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