Abstract: This handbook is intended as a ready reference guide to the control and management tactics for the more important plant diseases in the Pacific Northwest.
Abstract: Seed Treatments Promote Seedling establishment and help reduce yield and quality losses due to many pathogens and insects. The ability of seed treatments to control fungal diseases has made them a great success story of disease prevention.
Soilborne Fungal Diseases
Abstract: Cephalosporium stripe (fungus stripe) is a vascular wilt-type disease of wheat and barley, which also affects other cereals and grasses. lt is caused by the soilborne fungus Cephalosporium gramineum. ln autumn, the fungus produces millions of bacteria-sized spores (conidia), which are washed into the soil around the plant. These spores are the structures that will eventually infect the plant.
Abstract: Farming systems, equipment, climate, topography, and crops vary widely in the Pacific Northwest. Because of this complexity, managing root and crown diseases of cereal crops is not always simple or straightforward. Recommendations are usually part of a system-wide approach based on the fundamental practices described in this publication.
Abstract: Root and crown rots often go unnoticed, reducing yield until large patches of fields are missing plants or white, empty heads appear at crop maturity. Best management practices occur at planting and include using a seed treatment, crop rotation, and variety selection. There are no curative treatments for root and crown diseases. Positive identification and specific management recommendations for root and crown diseases can be obtained from your local county Extension office.
Abstract: Snow mold diseases of wheat are some of the most dramatic and devastating diseases of plants. In the Pacific Northwest, the snow molds are important in areas where snow falls on unfrozen or lightly frozen soil and persists for 100 days or more.
Abstract: Strawbreaker foot rot, which is also called eyespot, is a common and serious disease of winter wheat throughout most of eastern Washington, especially in the high rainfall regions. Yield loss varies considerably depending upon when plants are infected and the percentage of plants infected, but can range up to 50% in commercial fields when disease is severe.
Abstract: The level of stripe rust severity has varied considerably since 2010, with the disease incidence greater in 2010 and 2011 than it was in 2012 and 2013. The difference between years has many causes.
Abstract: The North Central Regional Committee on Management of Small Grain Diseases (NCERA-184) has developed the following information on fungicide efficacy for control of certain foliar diseases of wheat for use by the grain production industry in the U.S. Efficacy ratings for each fungicide listed in the table were determined by field testing the materials over multiple years and locations by the members of the committee.
Abstract: Proper diagnosis and evaluation of the potential yield loss due to foliar leaf diseases are some of the most difficult disease-oriented decisions a producer will make. Leaf diseases can be confusing to diagnose because the symptoms of different diseases look very similar.
Abstract: Fisarium head blight is a destructive disease of wheat and barley in Montana and in most wheat-growing regions around the world. The primary symptom of the disease is bleaching of some of the florets in the head before maturity
Abstract: Rust diseases are among the most widespread and economically important diseases of cereal crops worldwide. Three distinct diseases, leaf rust, stripe rust and stem rust, occur on wheat and barley in North America. The fungi that cause these diseases are notorious for their ability to increase rapidly and overcome the resistance of wheat or barley varieties.
Abstract: Stem rust, leaf rust, and stripe rust comprise a complex of diseases that reduces wheat and barley grain production. These rust diseases occur in nearly all areas of the United States and Canada. The importance of any member of the complex at a given location is determined by specific interactions with current wheat varieties, crop growth stage, and weather conditions.
Abstract: There are several economically important viruses in Montana cereal grain crops. The principal virus causing disease is Wheat streak mosaic virus. However, there are additional mite-transmitted viruses, aphid-transmitted viruses, and soilborne viruses that may be important. The purpose of this publication is to describe 1) the principle viruses of importance in cereal crops in Montana, 2) how to recognize virus-infected plants, 3) how viruses move from plant to plant, and 4) how to manage them.
Reaction of Winter Wheat Cultivars and Breeding Lines to soilborne Wheat Mosaic, 2011 (PDMR 6:CF025)
Abstract: Field plots were sown in a center-pivot-irrigated field in Quincy loamy fine sand (pH 8.0) near Umatilla, OR on 30 Sep 10. Seed for three separate nurseries, Oregon soft winter elite, Oregon hard winter elite, and Washington advanced winter, were sown in the same location at the rate of 90 lb/A in seven-row plots, 5.0 ft wide by 15 ft long, with 8-in. spacing between rows.
Cereal Cyst Nematodes: Biology and Management in Pacific Northwest Wheat, Barley and Oat Crops – 2010 (PNW 620)
Abstract: Nematodes are tiny but complex unsegmented roundworms that are anatomically differentiated for feeding, digestion, locomotion, and reproduction. These small animals occur worldwide in all environments. Most species are beneficial to agriculture. They make important contributions to organic matter decomposition and the food chain. Some species, however, are parasitic to plants or animals. One type of plant-parasitic nematode forms egg-bearing cysts on roots, damaging and reducing yields of many agriculturally important crops.
Abstract: Root lesion nematodes are microscopic roundworms that parasitize agricultural crops in every part of the world. Two species of root lesion nematode, Pratylenchus thornei and Pratylenchus neglectus, are damaging to wheat. Our neighboring states of Washington, Oregon and Idaho experience annual yield losses in spring wheat due to infestations of both nematode species.