Winter Squash Research Report-Back and Tasting��

Edmund Frost

Common Wealth Seed Growers

Commonwealthseeds.com/research

VABF Conference 2017

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Common Wealth Seed Growers received a Producer SARE grant to do winter squash research and breeding work in the 2016 growing season.

“Evaluation and Improvement of Winter Squash for Downy Mildew Resistance and Fruit Quality”

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��2014 Winter Squash Trial�Twin Oaks Seed Farm���

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Winter Squash Trial August 28^th 2014. Border squash is Waltham, and very heavily impacted by DM.

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Brix testing winter squash in late December 2014.

Conclusions from 2014 Trial

• Many moschata squash varieties (mostly from tropical and subtropical areas) have good Downy Mildew resistance, but usually have at least one of the following problems: splitting, poor eating quality, too long of a season, excessive variability, poor keeping quality, large size.
• Northern winter squash we tried did not have good DM resistance (including Waltham, JWS 6823, Acorn Table Queen) and did not perform well in the trial.
• C. maxima and C. pepo varieties had trouble with vine borers, while C. moschata varieties did not. C. maxima varieties also had Bacterial Wilt.
• Our Seminole-Waltham F3 already had far superior DMR to Waltham.
• Standouts included Chinese Tropical Pumpkin, Cuban Neck Pumpkin, Seminole-Waltham, Seminole, Soler, Thai Kang Kob.

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2016 Project Elements

• Chinese Tropical Pumpkin Selection (39 plants)
• Seminole Pumpkin Selection (42 plants)
• Cuban Necked Pumpkin Selection (40 plants)
• Breeding Trial and Selection with Fifth Generation Seminole-Waltham Cross Plants (108 plants)
• Winter Squash Variety Trial (24 varieties)

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Growing Methods

• Certified organic fields and methods
• No pest control products used (no sprays or row cover)
• Direct seeded
• Late planting to increase Downy Mildew exposure
• Tractor cultivated fields
• All plants or plots are trained and evaluated separately
• Approx. 9 foot row spacing

Chinese Tropical Pumpkin Selection Project

-At Twin Oaks Seed Farm in Louisa County VA, grown by River Oneida

-39 Plants, evaluated for yield and DM resistant foliage.

-The 16 best yielding and best growing plants evaluated for flavor, brix and dry matter.

-Seedstock is derived from Crowning F1, from Known-You Seeds in Taiwan. Segregation is present, but not pronounced. Was a standout in Twin Oaks 2014 trial. Rich flavor with high brix and dry matter.

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Results from Chinese Tropical Pumpkin Selection Project

• Found 9 plants with good combination of yield, DMR foliage, and eating quality (median brix over 11.5, dry matter over 18, flavor of hazelnuts). We are selling seed from these plants this year.
• Found four standouts with yields over 70 pounds per plant, good DMR and excellent eating quality.
• Only some of the best selections were self-pollinated.
• Would benefit from another year of selection.

Cuban Neck Pumpkin Selection Project

-Grown by Lyndsey Walker in Buckingham County VA

-40 Plants, all trained separately.

-Standout from 2014 Trial.

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Seminole Pumpkin Selection Project

-At Sycamore Farm in Botetourt County VA.

-42 plants, evaluated for Downy Mildew, Bacterial Wilt and yield.

-The 20 best growing and yielding plants were evaluated for flavor, brix and dry matter.

-All plants were self-pollinated because growout was not isolated.

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Results from Seminole Selection Project

• Found 5 plants with good combination of yield, Downy Mildew resistance, no Bacterial Wilt; as well as good flavor, brix (over 11 on the best fruit tested of each plant) and dry matter (over 14 on the best fruit tested).
• All the top selections were self-pollinated.
• Next year we will do seed production using only selfs of top selections (grown together).
• Did not find much variation in seed cavity size.

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Seminole-Waltham Breeding Trial and Selection

-Grown at Sycamore Farm in Botetourt County VA

-108 Plants from 6 selections made in 2015 and a cross of two 2015 selections made over winter of 2015-2016.

-All plants were trained separately and evaluated for Downy Mildew resistance, yield per plant and yield per square foot.

-The 46 best growing and yielding plants were evaluated for flavor, brix and dry matter (will also look at keeping quality).

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Waltham Butternut (2012 Crop)

Seminole x Waltham F1

Seminole x Waltham F3

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Waltham foreground, Seminole behind - August 28^th.

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Waltham foreground, Seminole x Waltham F3 behind – September 3^rd.

Seminole – Waltham July 7^th

8.5 foot row spacing; 8 foot in-row spacing; direct seeded on June 10^th (and June 25^th for plants 91-108)

Field fertilized with chicken manure, later side dressed with small amount of rock phosphate, potassium sulfate and Symphony (chicken manure granular fertilizer)

Seminole-Waltham September 26th

Plant 57, September 26th

Plant 58, September 26th

Plant 66, September 26th

Plant 68, September 26th

Plant 75, September 26^th

Fruit from Plant 68, October 14th

Fruit From Plant 57, October 14th

Fruit From Plant 72, October 22nd

Fruit From Plant 75, October 22nd

Results of Seminole-Waltham Breeding Trial

• Found 17 plants with good combination of Downy Mildew resistance, yield, flavor, brix (10 that had median brix over 11), dry matter (15-20%), shape. We are currently selling seeds from these plants.
• I was pleased with the flavor / absence of off flavors in all but one of the plants that had good brix and dry matter.
• Found three especially good selections (plants 57, 68 and 75), which excelled for eating quality, Downy resistance and yield. I will be moving forward in breeding work using these selections and a few others.
• Successfully self pollinated all the best selections.

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2016 Winter Squash Variety Trial

• 24 varieties/seedstocks
• 2 replications for most seedstocks
• 9 foot row spacing; 2.5 foot in-row spacing; 3 plants per plot; 10 feet between plots
• Evaluated Downy Mildew resistance, yield per plot, yield per square foot, brix, dry matter and flavor
• Several of the entries were lines from different stages of the Seminole-Waltham project. Part of the goal was to assess progress of this breeding work.
• Another goal was to identify new standout varieties.
• More commercial butternut varieties were included in the trial (JWS 6823 F1, Waltham, Naragansett F1, and Bugle) than in the 2014 Twin Oaks trial.

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Field Day - September 22nd

Narragansett F1 9/27

Bugle 9/27

JWS 6823 F1 9/27

Chinese Tropical Pumpkin 9/27

Seminole-Waltham F5 Selection 5 9/27

Seminole-Waltham F5 Selection 2 9/27

(Seminole-Waltham F5) X JWS 6823 F1 9/27

Results and Findings from Variety Trial�

• Waltham has worse Downy Mildew resistance than any other squash, including other commercial butternuts.
• Seminole Pumpkin had bad Bacterial Wilt. It was the first time I had seen it to this extent. Seminole was the only variety that got it.
• Seminole-Waltham had a lot of variation in eating quality. Early lines had variation within each line; later lines had variation more between lines. There were fruits with eating quality comparable to the commercial butternuts, but more than half not. There is potential but its important to keep working.
• Chinese Tropical Pumpkin had generally good results but also issues of variability. This conforms to what we found in the Chinese Tropical Pumpkin selection project.
• Seminole-Waltham had better DM resistance than the commercial butternut lines.

More Results and Findings from Variety Trial

• The commercial butternuts are shorter vined than most other entries, including Seminole-Waltham. This makes it hard to compare yield. To address this I measured approximate area of each plot, and calculated yield per square foot. The Seminole-Waltham lines had higher yield per plant than the commercial butternuts, but comparable yield per sq. foot.
• An untrained trial design with larger plots that have variable spacing (whatever is best for each entry) could do better at comparing yield between varieties in field conditions. I hope to do this in the future.
• The Seminole-Waltham lines tended to have better keeping quality than the commercial butternut varieties.
• Some varieties had a problem with Black Rot, especially Bellevue Butternut and Can Tho Tourist.
• The only new standout variety was a cross between Thai Pumpkin 45 and Pequenia Asar (Spanish Butternut). Tentatively calling this ‘Blue Moon.’
• Cuban Neck Pumpkin did notably worse than in 2014 and worse than expected.
• JWS 6823 usually had off flavors to our taste, and Bugle and Narragansett did as well but to a lesser extent. Waltham and Seminole-Waltham had only occasional off flavors.

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