Nearly complete sequences of RNA-CP and 3'-proximal RNA-TGB were determined for 43 samples of potato mop-top virus (PMTV) originating from potato tubers and field soil from Sweden, Denmark and the USA. The results showed limited diversity and no strict geographical grouping, suggesting only a few original introductions of PMTV from...
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Åkerblom • Mogens Nicolaisen •
Steen Lykke Nielsen • James M. Crosslin • Philip B. Hamm • Johanna Santala
Russet Burbank, Russet Norkotah, and Shepody tubers infected with Potato virus Y strains (PVYO, PVYN:O, PVYNTN) were tested from storage at 4A degrees C at the initiation of sprouting and then the same tubers were tested again from storage at 4A degrees C seventy eight days later. Samples were taken...
Zebra Chip (ZC) was confirmed in the Columbia Basin potato production area of Oregon and Washington in 2011. This is a serious disease first documented in Saltillo, Mexico in 1994. In 2000 the disease was identified in South Texas and since then, ZC has been reported in Arizona, California, Colorado,...
Nearly complete sequences of RNA-CP and 3'-proximal RNA-TGB were determined for 43 samples of potato mop-top virus (PMTV) originating from potato tubers and field soil from Sweden, Denmark and the USA. The results showed limited diversity and no strict geographical grouping, suggesting only a few original introductions of PMTV from...
Describes the symptoms and damage caused by silver scurf, a fungal disease of potatoes. Includes color photos of symptoms. Discusses sources of inoculum and the disease life cycle. Suggests management practices (seed selection, crop rotation, seed treatments, management of die-down, sanitation, harvest, and storage) to minimize disease problems.
Two types of smut attack corn in the Pacific Northwest: common smut and head smut. This publication provides descriptions of symptoms and the disease cycle, and management strategies (which differ considerably between the two types). There is also significant new information, particularly related to common smut, regarding losses and control...
In Kentucky bluegrass (Poa pratensis), Claviceps purpurea, the causal agent of ergot, typically releases ascospores during the early-morning hours, between about midnight and 10:00 A.M., corresponding to time of flowering, when the unfertilized ovaries are most susceptible to infection. During aeromycology studies of C. purpurea in perennial ryegrass (Lolium perenne)...
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County Extension Service, La Grande 97850;
Philip B. Hamm,Department of Botany and Plant Pathology
Ergot, caused by Claviceps purpurea, is a major disease of perennial ryegrass grown for seed in eastern Oregon. The objective of this research was to quantify and describe the spatial patterns of ergot severity in each of three 50-ha commercial fields of perennial ryegrass grown for seed in 2012 and...
In Kentucky bluegrass (Poa pratensis), Claviceps purpurea, the causal agent of ergot, typically releases ascospores during the early-morning hours, between about midnight and 10:00 A.M., corresponding to time of flowering, when the unfertilized ovaries are most susceptible to infection. During aeromycology studies of C. purpurea in perennial ryegrass (Lolium perenne)...
In Kentucky bluegrass (Poa pratensis), Claviceps purpurea, the causal agent of ergot, typically releases ascospores during the early-morning hours, between about midnight and 10:00 A.M., corresponding to time of flowering, when the unfertilized ovaries are most susceptible to infection. During aeromycology studies of C. purpurea in perennial ryegrass (Lolium perenne)...
Silver scurf is caused by a fungus, Helminthosporium solani, a relatively new problem related to potato production in North America. It wasn’t until the early 1990s that this fungus was identified as being a serious problem in the Pacific Northwest. This fungus produces a surface blemish on tubers, causing them...
Potatoes are an excellent choice for the home garden. They emerge quickly and grow rapidly. Potatoes yield well under most soil and growing conditions and can be stored for long periods without canning, drying or freezing.
Nearly complete sequences of RNA-CP and 3'-proximal RNA-TGB were determined for 43 samples of potato mop-top virus (PMTV) originating from potato tubers and field soil from Sweden, Denmark and the USA. The results showed limited diversity and no strict geographical grouping, suggesting only a few original introductions of PMTV from...
This book provides an illustrated guide to the identification and management of fungi, insects, and abiotic conditions that cause problems in Northwest bareroot conifer nurseries. A key to nursery pests offers initial guidance in identification. Separate chapters address individual pests with details on recognition, damage cycle, and management practices to...
This publication addresses the emergent issue in the Pacific Northwest of a potato infection called zebra chip disease, vectored by the potato psyllid. Includes information on the bacterium, the biology of the vector, description of damage from both vector and non-vector psyllids, and most current research on management.