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Fundamental Differences Between Conventional and Organic Tomato Agroecosystems in California
In an integrated, multidisciplinary study we compared ecological characteristics and productivity of commercial farms categorized as either organic (ORG) or conventional (CNV) based on their use ofExpand
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Variables associated with corky root and phytophthora root rot of tomatoes in organic and conventional farms
In 1989 and 1990, a comparative study of organic and conventional tomato-production systems in the Central Valley of California was conducted to determine the effects of management practices on soilExpand
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Races of Phytophthora sojae in Iowa soybean fields.
During 1991 to 1994, Phytophthora sojae was isolated from plants or soils in 50 Iowa counties. Eighty-two isolates from soil and 124 isolates from diseased soybean plants were collected and tested.Expand
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Regional Assessment of Soybean Brown Stem Rot, Phytophthora sojae, and Heterodera glycines Using Area-Frame Sampling: Prevalence and Effects of Tillage.
ABSTRACT The prevalence of brown stem rot (caused by Phialophora gregata), Heterodera glycines, and Phytophthora sojae in the north central United States was investigated during the fall of 1995 andExpand
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Economic impact of Wheat streak mosaic virus in the Texas High Plains
Wheat streak mosaic virus, vectored by the wheat curl mite Aceria tosichella Keifer, is a major limiting factor in wheat production in the Texas Panhandle. It is the most frequently encountered virusExpand
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Prevalence of sclerotinia stem rot of soybeans in the north-central United States in relation to tillage, climate, and latitudinal positions.
ABSTRACT Since the early 1990s, Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, has caused considerable damage to soybean production in the north-central United States. To determine theExpand
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Characterization and Distribution of Two Races of Phialophora gregata in the North-Central United States.
ABSTRACT Genetic variation and variation in aggressiveness in Phialophora gregata f. sp. sojae, the cause of brown stem rot of soybean, was characterized in a sample of 209 isolates from theExpand
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Effects of Wheat streak mosaic virus on Root Development and Water-Use Efficiency of Hard Red Winter Wheat.
Greenhouse and field studies were conducted to determine the effects of Wheat streak mosaic virus (WSMV), a member of the family Potyviridae, on root development and water-use efficiency (WUE) of twoExpand
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Zebra chip disease and potato biochemistry: tuber physiological changes in response to 'Candidatus Liberibacter solanacearum' infection over time.
Zebra chip disease, putatively caused by the bacterium 'Candidatus Liberibacter solanacearum', is of increasing concern to potato production in Mexico, the United States, and New Zealand. However,Expand
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Similarities and differences in physiological responses to 'Candidatus Liberibacter solanacearum' infection among different potato cultivars.
Zebra chip disease (ZC), putatively caused by the fastidious bacterium 'Candidatus Liberibacter solanacearum', is a threat to potato growers worldwide. However, little is known about biochemicalExpand
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