Read more about the article Differentiation and detection of blueberry scorch strains

Differentiation and detection of blueberry scorch strains

The Blueberry scorch virus (BlScV) was first identified in Oregon and Washington in 1987, and later in British Columbia in 2000. It has been found in over 140 blueberry fields in British Columbia. BlScV isolates exhibit a wide range of sequence diversity, with the 'Northwest' strains showing similar diversity to all blueberry scorch virus isolates. Cranberries have been identified as a host of BlScV, with infected bogs found in British Columbia, Washington, and Oregon. In British Columbia, the close proximity of cranberry and blueberry crops allows for efficient transmission of the virus. However, in Oregon and Washington, where cranberries are grown far from major blueberry production areas, transmission by aphids from cranberry to blueberry is limited. Efforts are being made to identify and remove infected bushes and implement control measures to eliminate the virus from affected fields in Oregon and Washington. The diverse strains of blueberry scorch virus make tracking and eradicating the virus challenging. Research efforts are underway to establish a reliable detection method and compare the 'Northwest' strain of the virus with more severe strains found in the northeastern U.S. and British Columbia. This research aimed to investigate the potential for eradicating BlScV from infected fields in Oregon and Washington.

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Read more about the article Can humic acids improve production in mature organic northern highbush blueberry?

Can humic acids improve production in mature organic northern highbush blueberry?

A 3-year study was conducted to investigate the effects of adding humic acids to an organic blueberry fertigation program. The objective is to see if adding organic-approved humic acids to a standard fertilization program in a mature organic blueberry production system will increase yield and affect soil quality and plant nutrients. The study compared the yield, fruit, and leaf nutrient concentration, and soil nutrients of 'Duke' and 'Liberty' blueberry cultivars with and without humic acid application. Over the three years, adding humic acids did not significantly improve yield or alter soil characteristics and plant nutrient levels. The study found no substantial evidence to support the additional cost of adding humic acids to an already healthy and productive organic blueberry system.

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Read more about the article The effect of soil parameters on plant-parasitic nematodes of wine grapes in Washington and Oregon

The effect of soil parameters on plant-parasitic nematodes of wine grapes in Washington and Oregon

Plant parasitic nematodes are costly pests that cause global crop loss of over $100 billion dollars. Previously it was thought that the large populations of ring nematode in Oregon and Northern root-knot nematode in Washington vineyards were caused by differences in soil characteristics. It was found that soil texture had no influence on both types of nematode population growth. It was found that Northern root-knot nematodes that live inside of the roots thrived in acidic (low pH) soil more than alkaline (high pH) soil. It was found that soil pH had no effect on ring nematodes that live outside of the roots. Also generated was a computer model to automate nematode egg counting. These results will help generate parasitism risk maps, helping wine grape growers make better vineyard planting decisions, and will increase the speed with which scientists can identify plant parasitic nematode eggs.

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Read more about the article Risk assessment of nematode-transmitted viruses of small fruit crops in the Pacific Northwest

Risk assessment of nematode-transmitted viruses of small fruit crops in the Pacific Northwest

The Pacific Northwest (PNW) maintains a $840 million small fruit industry susceptible to nepoviruses, which are viruses that are transmitted by dagger nematodes. The association of viruses with nematodes is complicated with many nepoviruses, taxonomic confusion among vector nematodes, and limited data on the ability of Xiphinema spp. populations to vector many of the nepoviruses. Research was conducted to provide an up-to- date assessment of the problem in the region and to develop new molecular tools to improve detection of this disease complex. Over two years, 96 small fruit fields and vineyards were sampled in the PNW. In total 43 vineyard, 24 blueberry, 15 raspberry, 8 blackberry, 5 strawberry and one ribes fields were assessed for dagger nematode and nepoviruses. The highest incidence of dagger nematode was found in grape vines (79 %) followed by raspberry and blueberries. The population densities were 56 and 37 nematodes per 250 cc of soil in grapes and blueberry, respectively. Tomato ringspot virus (ToRSV) was found in three blueberry fields, while, in grape, raspberry and ribes only one field each. Tobacco ringspot virus (TRSV) was found in six vineyards.

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Read more about the article Botrytis Bunch Rot: Where, When, and What to use

Botrytis Bunch Rot: Where, When, and What to use

From 2020-2022, eleven sites from nine different vineyards in Oregon, and four in Washington were surveyed for Botrytis by sampling grape inflorescence and developing fruits, vineyard floor debris (prior year grape rachis), and nuisance blackberries. Botrytis on grape inflorescence and fruits varied from site to site and year to year likely due to yearly disease pressure differences and unique site microclimates. Prior year dead grape rachis on the vineyard floor with sporulating Botrytis infestations varied from year to year as well, but generally declined as the season progressed. Incidence of Botrytis on vineyard floor debris in all but one site in 2021 was over 75% in late April and all sites sampled decreased over time to under 25% by September. Wild nuisance blackberry flowers and fruits adjacent to the vineyard were also found to be potential sources of Botrytis inoculum throughout the season. Inoculum estimation from historical spore trap DNA samples originally taken to monitor powdery mildew in the Willamette Valley were re- assayed for Botrytis inoculum.

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