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Field Notes · July 31, 2014

From the Field: Carrot, Spinach, and Onion Seed

We're noticing some differences in plant health and suspect we’re seeing varying levels of resistance to Xanthomonas (a bacteria that causes black leaf spot). The red plants are the ones that have likely succumbed to infection and the green ones are those most likely carrying some resistance. OSA's plant breeders will be selecting seed from strong plants this fall.
Carrot Improvement for Organic Agriculture (CIOA) trial. Copyright OSA.

Last month we shared some notes from our carrot breeding work happening at Midori Farm as part of the collaborative Carrot Improvement for Organic Agriculture (CIOA) project. This week we noticed some differences in plant health and suspect we’re seeing some varying levels of resistance to Xanthomonas (a bacteria that causes black leaf spot). The red plants (see picture to the left) are the ones that have likely succumbed to infection and the green ones are those most likely carrying some resistance. We’ll be selecting seed from strong plants in late August or early September.

Carrot Improvement for Organic Agriculture (CIOA) weed competitiveness trials. Copyright OSA.
CIOA weed competitiveness trials. Copyright OSA.

You’ll notice some big differences in top size and a few weeds in the photo of our CIOA weed competitiveness trial to the right. We are looking at the rate of growth and the fullness of canopy as a way to quantify the ability of carrot varieties to compete with weeds. Later this season, we will combine this data with plant and weed biomass and yield measurements to see how the weeds affected plant growth and root yield. Each plot is split in half with one half that is actively weeded each week and the other left to the weeds. We are proud to be collaborating on this work with researchers at the University of Wisconsin – Madison.

‘Abundant Bloomsdale’ spinach seed production. Copyright OSA.

Midori Farm is also home to the production of our ‘Abundant Bloomsdale’ spinach seed. The spinach seed field looks excellent, and we’re excited to be moving closer to a commercial release of this variety to the public. (Learn more about this organic plant breeding project here.)

We are also conducting an onion trial at Midori Farm that is supported by a Washington Department of Agriculture and Oregon Department of Agriculture Specialty Crop Grant. One of the qualities we are looking for in onions is some level of resistance to Downy Mildew, which can seriously hamper bulb development and health. We’re currently experiencing some Downy Mildew infection in the patch and are happy to see some strong differences among the varieties (see photos below). The trial includes both standard varieties and some advanced breeding material from the University of Wisconsin – Madison. This trial is also being repeated in Oregon at Gathering Together Farm.

Stay tuned for results from these trials later this fall. And don’t forget to brush up on your own plant breeding and seed production skills by checking out these related OSA publications: How to Breed Carrots for Organic Agriculture, Principles and Practices of Organic Spinach Seed Production in the Pacific Northwest, and On-farm Variety Trials: A Guide for Organic Vegetable, Herb, and Flower Producers.

Our onion variety trial at Midori Farm. This work is funded by Specialty Crop Block Grants from the Washington Department of Agriculture and Oregon Department of Agriculture.
Our onion variety trial. These onions are showing good resistance to Downy Mildew. Copyright OSA.
Onion trial showing some damage from Downy Mildew. Copyright OSA.
Onion trial showing some damage from Downy Mildew. Copyright OSA.

 

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Crops: Carrots, Onions, Spinach

Regions: Pacific Northwest

Categories: Field Notes

Tags: Carrot Improvement for Organic Agriculture (CIOA)

Laurie McKenzie

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