Epidemiology and Management of Plant-parasitic Nematodes in Winegrapes

Nematodes are root feeding organisms that can cause direct damage and can also be a virus vector. Nematodes can severely limit the successful establishment of vines and vineyards and impact production yields by 5-20%. There are several products available to growers to assist in managing Nematode populations and increase successful vine establishment. This research evaluates combinations of synthetic (at half the recommended commercial rate) and biological nematicides to reduce populations of plant-parasitic nematodes, and increase populations of free-living beneficial nematodes and to increase vine productivity.

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Detection and monitoring of Tomato Ringspot Virus in red raspberry and Xiphinema americanum.

Washington and Oregon account for 85% of national raspberry production and 15% of worldwide production. Growers from Washington and Oregon harvest over 80 million pounds of raspberries on about 12,000 acres. Tomato ringspot virus (ToRSV) continues to be a problem in raspberry production in the Willamette Valley in Oregon, and in southern Washington. The predominant mode of spread of ToRSV is via the nematode vector Xiphinema americanum, also known as “Dagger” nematodes. Methyl bromide is often a method of choice for managing ToRSV and other nematode-borne plant viruses because it kills the nematode vectors. However, ToRSV often reappears within 3-4 years of fumigation with methyl bromide.

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Diversity of Pseudomonas syringae and diagnosis and management of bacterial canker on blueberry

Bacterial canker caused by the bacterial pathogen Pseudomonas syringae is characterized by killed buds and stems. The disease can be severe when environmental conditions support growth and infection of tissues in the fall and spring. The disease is especially damaging to young succulent plants. Copper is sprayed onto plants to control the growth of the pathogen and the development of bacterial canker. P. syringae actually refers to a complex group of pathogens, with individual members that have either a wide host range or narrow host range. Surprisingly, little was known about P. syringae causing bacterial canker on blueberry. It was not known if only a single type of P. syringae with a narrow host range caused bacterial canker or if multiple types of the pathogen complex caused bacterial canker. P. syringae can use many traits to cause plant diseases, such as the production of plant toxins or the ability to nucleate ice formation.

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It takes a village: Understanding barriers to regional cooperatives for pest and disease management

abstract An individual grower’s response to pests and diseases in their vineyard can have consequences for an entire growing region. Collective action strategies can help align disease responses to achieve…

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Sweet SWD control: non-target effects and field trials with erythritol

Erythritol is a non-caloric sugar used in artificial sweeteners such as Truvia and is safe for human consumption. Formulations with erythritol have induced mortality among spotted-wing drosophila (SWD) adults in the lab and greenhouse, and reduced infestation rates among fruits in the field. While promising, the erythritol formulation needs to be improved for field application and its non-target effects considered. Recently, we developed two new formulations to reduce the stickiness of sprays

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