Final report for FS20-325
Using selective breeding to address disease problems can be an extremely effective solution that causes none of the environmental and health dangers posed by chemical fungicides (which are unfortunately the current go-to for downy mildew (DM)). Moreover, eliminating or reducing need for chemical sprays saves farmers money and improves feasibility of Southeast production. DM in cucumbers was effectively controlled for many years by the use of resistant varieties. We aim to do the same with butternut squash, and whats more we aim to develop and utilize diverse sources of DM resistance so that the resistance will be more durable and resilient in the face of potential changes to the pathogen in the future. This includes using Seminole Pumpkin, San Jose Mountain Club Squash, Guatemalan Green Ayote and Chinese Tropical Pumpkin as DM resistance sources.
South Anna Butternut, a variety Common Wealth Seed Growers developed from a cross between Seminole Pumpkin and Waltham Butternut, had shown promise for DM resistance in our small plot trials (prior to this project). We have also gotten feedback from many farmers who have noticed its DM resistance and fruit quality. However, we felt more information was needed to assess its potential in the region in comparison to other varieties in terms of not only DM resistance, but productivity and fruit quality.
We also started this project with several seedstocks developed by crossing South Anna to other varieties (Atlas, JWS 6823, Guatemalan Green Ayote, and Chinese Tropical Pumpkin). One of our goals was to evaluate these populations and to begin selecting from them for traits such as richer flavor, higher DM resistance, storage quality, higher fruit set, shorter vine length, larger fruit size (for processing), smaller fruit size (for market) . Part of the impetus for these crosses came from feedback from Clifton Seeds’ large scale 2018 test of South Anna. They said it stood out for DM resistance but needed higher fruit set and larger fruit (many of their seed customers grow for processing).
In addition, Care of the Earth Community Farm has been trialing moschata squashes for several years. This project included evaluation and selection of the population they created by crossing Waltham and San Jose Mountain Club.
All our work with squash at Twin Oaks Seed Farm and Care of the Earth Farm is conducted on certified organic land, with minimal pest and disease control inputs. As a result our selections are well suited to survive the pest and disease challenges that Southeast organic growers face. This also stands to benefit conventional growers by reducing need for chemical inputs.
Very early planting is one way organic growers and some conventional growers have handled DM. Limitations are that summer-harvested butternut crops don't keep long into the fall, and that in some years severe DM comes early. South Anna, and other varieties we are developing, are intended to be grown in high DM conditions for fall harvest, allowing fruits to keep longer into the fall and winter. Note that assessing the performance of very early planted, summer-harvested butternuts is beyond the scope of this project.
The project had four elements:
1)2020 breeding trials at Twin Oaks Seed Farm and Care of the Earth Farm. This entailed evaluating separately trained plants as individuals. 194 plants were evaluated at Twin Oaks Seed Farm - populations included South Anna; Guatemalan Green Ayote (which likely has some Chinese Tropical Pumpkin mixed in); and crosses between South Anna and Atlas, Chinese Tropical Pumpkin, Guatemalan Green Ayote, and JWS 6823. The breeding trial of 125 plants at Care of the Earth Farm focused on a population derived from crossing Waltham and San Jose Mountain Club. We looked at yield per plant, eating quality, and keeping quality. The goal here was to advance breeding work by identifying and saving seed from standout plants; as well as to compare different populations to each other.
2)On-farm large block trials: We compared South Anna with Atlas F1, Quantum F1, Metro F1, Avalon F1 in blocks of approximately 3200 square feet. Large block trials took place at four organic farms in Virginia, North Carolina, and South Carolina: Wild Hope Farm, Lomax Farm, Living Web Farm, and Twin Oaks Seed Farm. The goal was to get information from several farms about how South Anna compares to other varieties at field production scale. We looked at yield, eating quality and keeping quality.
3)The third element of the project was a screening of breeding lines and potential parents in smaller blocks that took place at both Care of the Earth Community Farm and Twin Oaks Seed Farm, with twelve 20-plant plots at Twin Oaks Seed Farm, and nine plots at Care of the Earth Community Farm. We looked at yield and eating quality.
4)2021 trials at Twin Oaks Seed Farm. In 2021 we compared small blocks of several 2020 selections and some new crosses. We also grew individually-trained plants derived from some 2020 selecions. The 2021 trials provided useful follow-up information to what we learned in 2020, and enabled us to make more progress with our selections.
- - Producer (Researcher)
- - Producer (Educator)
- - Producer
- - Producer (Educator and Researcher)
*Note that I've included some discussion of results in this section. See the following section (Results and Discussion) for data tables and pictures, and the Project Outcomes section for more discussion of results.
This project included both variety trials and breeding trials. With the variety trials we were able to test and compare the butternut seedstocks we are working with to other varieties, and to each other. In the breeding trials we compared different plants from our breeding populations, obtaining improved selections in the process. Most of this project took place in 2020, but we did follow-up trials in 2021 at Twin Oaks Seed Farm.
At Twin Oaks Seed Farm in 2020:
In our large block variety trial (planted in early June) we compared South Anna with three commercial hybrid butternuts - Atlas, Avalon and Quantum. Each variety was planted in a 40x80 foot block. Avalon showed poor downy mildew resistance, with the plants dying completely by early September. Atlas and Quantum showed DM resistance and productivity comparable to South Anna. Quantum also had better keeping quality. Atlas had problems with fruit splitting due to a heavy rain. South Anna had much better eating quality than Quantum and Atlas. See data table in next section.
In our small block variety trial (planted in early June) we compared 12 seedstocks including several different South Anna crosses. Blocks were 20x30 and trained so as not to intertwine. Standouts for a combination of good yield and eating quality included San Jose Mountain Club x Waltham (selection 2) and South Anna (75%) x Chinese Tropical Pumpkin (25%). Others that had good eating quality but with slightly lower yield included South Anna (Selection 202); Seminole x Rainbow (from Hawaiian Seed Network); and South Anna x Chinese Tropical Pumpkin (50/50). South Anna x Little Dipper F1 and Chinese Tropical Pumpkin had the best eating quality in the trial but lower yields. See data table in next section.
In our breeding trial we grew 78 separately-trained plants of different crosses made with South Anna (planting date June 7th). This included South Anna crossed with a Guatemalan Ayote (F1 plants); South Anna crossed with Atlas (F2 plants); an F2 population that is 75% South Anna and 25% JWS 6823; and an F1 population that is 75% South Anna and 25% Chinese Tropical Pumpkin. We made promising selections from all these seedstocks, focusing on plants that have good eating quality, keeping quality, productivity and DM resistance. The Guatemalan Ayote crosses were especially notable for their keeping quality and DM resistance. The JWS 6823 cross was notable for eating quality, deep tan color and small fruit size. The Chinese Tropical Pumpkin cross was notable for eating quality, appearance and productivity. The Atlas cross was very diverse, with less promising results, although some plants did well. We also grew 13 Guatemalan Green Ayote plants and selected for interior color (some are green on the inside), productivity, eating quality and keeping quality. It is likely that the original green-fleshed Guatemalan squash had some other squash crossed into it, possibly Chinese Tropical Pumpkin, making it shorter season but also less green. One of our goals in the breeding trial was to self pollinate all the plants in this breeding trial, and we came close, with about 90 percent self pollinated. In a different field we grew 22 F2 plants of a 50/50 cross between Chinese Tropical Pumpkin and South Anna. These didn't do well, perhaps due to lower fertility and higher squash bug pressure in that field. However, results from the small block trial (see below) also indicated that the 75/25 South Anna - Chinese Tropical cross worked better than the 50/50 cross. See data table in next section.
The South Anna Butternut breeding trial (in a separate, isolated field) included 94 separately trained plants, planted in early June. We evaluated for productivity, downy mildew (DM) resistance, dry matter, brix, and keeping quality. We also did taste tests. We saved open-pollinated seed from the best selections, with a special focus on keeping quality (this focus was largely informed by results from the large block variety trial - see below). South Anna is a new butternut variety bred from an initial 2011 cross of Seminole Pumpkin and Waltham Butternut. Although we named the variety in 2017 and have been selling seeds since then, we are still doing active selection. See data table in next section.
At Care of the Earth Farm in 2020:
Megan Allen of Care of the Earth Farm conducted a breeding trial with populations derived from a cross between Waltham Butternut and San Jose Mountain Club (a necked tropical pumpkin from Costa Rica), and was able to obtain improved selections. Megan also conducted a small block variety trial.
Large block trials also took place at Wild Hope Farm (South Carolina), Lomax Farm (North Carolina), and Living Web Farms (North Carolina). Wild Hope Farm got successful crops of the four varieties they grew (Quantum, Avalon, South Anna and Metro). Yields were 46, 44, 32 and 25 pounds per 1/8 acre respectively. This trial was planted very early and harvested in late July/early August, so downy mildew pressure was low and likely not a major factor. Eating quality was not evaluated. We didn't recieve data from the trial at Living Web Farms - the trial data was unfortunately lost due to it being stored on a device that broke without there being a backup. At Lomax Farm, predation from deer and squash bugs led to very minimal yields of all varieties.
In Hawaii over the winter of 2020-2021, Gabriel Sachter-Smith and Katie Ziemann crossed some of the best 2020 selections from the Twin Oaks Seed Farm breeding trials to each other. We trialed seven of these in small blocks at Twin Oaks Seed Farm in 2021. The best of these, in terms of combination of eating quality, keeping quality, and yield, was the cross that contains 12.5% JWS6823, 25% Guatemalan Green Ayote and 62.5% South Anna (entry ID 200x54). The two blocks that were 75% South Anna and 25% Guatemalan Green Ayote did very well for yields and keeping quality, but not so well for eating quality. See 2021 data table in next section.
In 2021 we also trialed the best (selfed) 2020 Guatemalan Green Ayote selections. Selection 70 did well for for yield, eating quality, keeping quality and greenness, while selection 78 did unexpectedly poorly. Selection 81 had low yield but very green flesh, likely representing uncrossed genetics from the original Guatemalan squash. Selection 75, while having some good characteristics, does not have the green flesh we're looking for in this squash. We were able to obtain a cross between selections 70 and 81. See 2021 data table in next section.
Also in 2021 we grew isolated breeding trials derived from some 2020 selections: 29 plants derived from 2020 selection 200 of our South Anna (75%) - JWS6823 (25%) cross; approximately 30 plants derived from 2020 selections 63 and 61 of our South Anna (75%) - Chinese Tropical Pumpkin (25%) cross. Both of these growouts were in isolated fields, and we saved seed from the best plants. See 2021 data table in next section. Note that while we recorded data on all 29 plants of the South Anna-JWS 6823 cross, we only took data on the 13 plants of the South Anna-Chinese Tropical Pumpkin cross that looked best at harvest time.
Following are data tables and pictures. See previous section (Material and Methods), as well as the Project Outcomes section for discussion of results. Data spreadsheets are also available at http://commonwealthseeds.com/data-tables-for-2020-2021-sare-research-grant-breeding-and-evaluation-of-butternut-squash-varieties-for-southeast-organic-farms/
Large Block Trial - Twin Oaks Seed Farm 2020 (Direct seeded early June)
|Variety Name||Total Yield (Bushels) 3200 sq foot blocks||Approx. Total Yield (Pounds per Acre)||% marketable in early December||Median Brix (6 fruits tested of each variety)||Median Dry Matter (6 fruits tested)||Downy Mildew Rating 9-14 (1-9 scale; 9 is worst)|
Small Block Trial - Twin Oaks Seed Farm 2020 (Direct seeded early June)
Marketable Yield (20x30 foot blocks)
|Number of Squash||Average Weight||Median Eating Quaity Rating* (1-5 scale, 5 is best)||Median Brix*||Median % Dry Matter*|
|South Anna x Little Dipper (F1)||124||52||2.4||4.5||11||15.8|
|South Anna x (Chinese Tropical x South Anna)||225.9||88||2.6||3||9.9||12.6|
|San Jose x Waltham 2||251||118||2.1||3||9||11.3|
|South Anna 202||194.5||70||2.8||3.5||9.5||12.1|
|South Anna x Atlas (F2)||162||44||3.7||1.5||7.1||8.9|
|Chinese Tropical Pumpkin||169||46||3.7||4||10.8||13.9|
|South Anna x Guatemalan Green Ayote||227||48||4.7||2||5.4||6.9|
|San Jose x Waltham 1||153||61||2.5||3||8.9||11.5|
|South Anna x Chinese Tropical||181||52||3.5||3.5||10.5||14.1|
|Seminole x Rainbow||186||49||3.8||4||9.9||13.4|
Breeding Trial - 2020 Twin Oaks Seed Farm (Direct seeded June 7th)
|Plant ID Number||Origin||Number of Good Squash||Weight||Number with Rot||Number Immature||9/30 Downy Mildew (1-9 rating, 9=worst)||Average Weight||Percentage keeping in early December||Median Brix||Median Dry Matter||Median Eating Quality Rating (5 is best)||Number of Tests (Brix, Dry Matter, Eating Quality)|
|1||Atlas x South Anna (F2)||7||36||0||2||7||5.1||100.0||7.7||11.4||3.3||2,2,2|
|2||Atlas x South Anna (F2)||4||23.4||0||3||8||5.9||11.2||3||0,1,1|
|3||Atlas x South Anna (F2)||5||19.8||3||0||8||4.0|
|4||Atlas x South Anna (F2)||10||32.2||1||2||5||3.2||75.0|
|5||Atlas x South Anna (F2)||9||30||2||4||5||3.3||50.0|
|7||Atlas x South Anna (F2)||7||41||0||1||3||5.9||100.0||8.9||13.4||3||2,2,1|
|8||Atlas x South Anna (F2)||6||22.8||0||2||9||3.8|
|9||Atlas x South Anna (F2)||10||29.7||0||0||9||3.0|
|10||Atlas x South Anna (F2)||6||27.1||0||4||4||4.5||80.0||10.6||16||3.5||4,2,3|
|11||Atlas x South Anna (F2)||5||34.9||1||2||6||7.0||100.0||11.2||14.8||3||2,1,2|
|12||Atlas x South Anna (F2)||13||49.2||0||2||5||3.8||50.0||11.1||16.7||1,1,0|
|13||Atlas x South Anna (F2)||7||38.2||0||3||5||5.5||100.0||10.6||11.1||3.5||3,2,3|
|14||Atlas x South Anna (F2)||7||33.5||1||3||7||4.8|
|15||Atlas x South Anna (F2)||9||23.6||0||6||4||2.6||100.0||9.5||12.3||2.5||3,1,3|
|16||Atlas x South Anna (F2)||5||28.2||0||4||3.5||5.6||100.0||10.3||15.7||3.5||3,1,3|
|17||Atlas x South Anna (F2)||10||36.7||2||3||5||3.7||66.7||10.6||14.7||3.5||4,2,3|
|18||Atlas x South Anna (F2)||5||22.3||2||2||7.5||4.5|
|19||Atlas x South Anna (F2)||13||34.9||0||0||9||2.7||75.0||7.6||10.5||1,1,0|
|20||Atlas x South Anna (F2)||11||26.3||0||7||3.5||2.4|
|21||Atlas x South Anna (F2)||6||34.5||1||0||7||5.8|
|22||Atlas x South Anna (F2)||0||0||4||0||7||#DIV/0!|
|23||Atlas x South Anna (F2)||3||13.4||4||0||9||4.5|
|24||Atlas x South Anna (F2)||4||16.4||4||7||8.5||4.1|
|25||Atlas x South Anna (F2)||8||39.6||3||0||9||5.0|
|26||Atlas x South Anna (F2)||5||23.6||3||0||9||4.7|
|27||Atlas x South Anna (F2)||4||12.7||5||0||9||3.2|
|28||Atlas x South Anna (F2)||8||30.2||2||0||8.5||3.8|
|29||Atlas x South Anna (F2)||2||9.2||5||1||8.5||4.6|
|30||Atlas x South Anna (F2)||13||50.8||0||0||8||3.9||72.7||10.6||14.8||1,1,0|
|31||Atlas x South Anna (F2)||2||7||8||5||7||3.5|
|32||Atlas x South Anna (F2)||6||32.7||0||1||8||5.5|
|33||Atlas x South Anna (F2)||6||44.5||0||0||4||7.4||100.0|
|34||Atlas x South Anna (F2)||9||28.3||0||0||8||3.1||75.0||10.7||16.4||4||1,1,1|
|35||Atlas x South Anna (F2)||18||68.3||3||1||9||3.8||76.9||1,0,1|
|36||Atlas x South Anna (F2)||5||22.5||3||0||7.5||4.5|
|37||Atlas x South Anna (F2)||12||32.1||4||0||9||2.7|
|38||Atlas x South Anna (F2)||6||37.9||2||2||4||6.3||100.0||8.6||11||2.5||3,1,3|
|39||Atlas x South Anna (F2)||1||7.4||5||1||4||7.4|
|40||Atlas x South Anna (F2)||2||6.8||7||0||7||3.4|
|41||Atlas x South Anna (F2)||8||37||0||2||8.5||4.6|
|42||Atlas x South Anna (F2)||10||42.6||2||0||6||4.3|
|MEDIAN||Atlas x South Anna (F2)||6||30||1||1||7||5.0|
|50||South Anna x Guatemalan Green Ayote||8||32.7||0||3||3.5||4.1||100.0||10.5||14.4||2,2,1|
|51||South Anna x Guatemalan Green Ayote||6||28.4||0||9||5||4.7|
|52||South Anna x Guatemalan Green Ayote||11||48||0||3||4||4.4||90.0||9.2||12.5||3.5||3,3,2|
|53||South Anna x Guatemalan Green Ayote||11||46.3||0||1||4||4.2||100.0||8.8||11.8||3,3,1|
|54||South Anna x Guatemalan Green Ayote||10||53.2||0||2||5||5.3||100.0||10.4||15.8||3.5||3,3,3|
|55||South Anna x Guatemalan Green Ayote||3||15.2||1||0||3.5||5.1|
|56||South Anna x Guatemalan Green Ayote||11||59.9||0||4||3.5||5.4||100.0||10||15.3||3.5||3,3,4|
|57||South Anna x Guatemalan Green Ayote||3||17||1||0||6||5.7|
|58||South Anna x Guatemalan Green Ayote||9||35.2||0||1||6||3.9||100.0||9.5||12.8||3.25||3,3,2|
|59||South Anna x Guatemalan Green Ayote||9||41.4||1||6||5||4.6||100.0||8.6||11.2||2,2,1|
|MEDIAN||South Anna x Guatemalan Green Ayote||9||38.3||0||2.5||4.5||4.3|
|60||South Anna x (South Anna x Chinese Tropical Pumpkin)||13||37.6||0||3||4||2.9||72.7||9.7||15.3||3.5||1,1,1|
|61||South Anna x (South Anna x Chinese Tropical Pumpkin)||10||40.6||0||0||5||4.1||100.0||10.8||13.7||3.5||4,4,3|
|62||South Anna x (South Anna x Chinese Tropical Pumpkin)||13||29.2||1||0||5||2.2||91.7||9.8||17.1||4||1,1,1|
|63||South Anna x (South Anna x Chinese Tropical Pumpkin)||9||31||0||2||5||3.4||100.0||10.9||16.3||4.5||4,4,3|
|64||South Anna x (South Anna x Chinese Tropical Pumpkin)||20||43.6||0||5||3.5||2.2||94.1||10.6||14.4||2,2,1|
|65||South Anna x (South Anna x Chinese Tropical Pumpkin)||2||9.4||3||1||6||4.7|
|66||South Anna x (South Anna x Chinese Tropical Pumpkin)||10||38.3||2||0||5.5||3.8||70.0|
|67||South Anna x (South Anna x Chinese Tropical Pumpkin)||13||42.8||8||3||5||3.3||91.7||8.8||11.9||3||1,1,1|
|MEDIAN||South Anna x (South Anna x Chinese Tropical Pumpkin)||11.5||37.95||0.5||1.5||5||3.3|
|70||Guatemalan Green Ayote||15||61.5||0||8||4.1||14.2||19.9||5||2,2,2|
|71||Guatemalan Green Ayote||12||44.7||0||4||3.7|
|72||Guatemalan Green Ayote||6||2.3||1||4||0.4||9.8||12.7||3||1,1,1|
|73||Guatemalan Green Ayote||2||12.4||0||1||6.2|
|74||Guatemalan Green Ayote||4||11.1||0||4||2.8|
|75||Guatemalan Green Ayote||11||43.5||0||3||4.0||9.4||12.4||3.8||2,2,2|
|76||Guatemalan Green Ayote||8||22.7||0||4||2.8||10||12.4||3||1,1,1|
|77||Guatemalan Green Ayote||3||12.4||0||7||4.1|
|78||Guatemalan Green Ayote||11||34.6||0||3||3.1||10.5||12.2||4.5||4,4,3|
|79||Guatemalan Green Ayote||7||20||0||2||2.9||11.1||16.4||5||1,1,1|
|80||Guatemalan Green Ayote||7||19.8||1||4||2.8|
|81||Guatemalan Green Ayote||3||16.5||0||3||5.5|
|82||Guatemalan Green Ayote||6||12.3||0||6||2.1|
|MEDIAN||Guatemalan Green Ayote||7||19.8||0||4||2.8|
|200||South Anna x (South Anna x JWS 6823)||19||41.4||0||3||3||2.2||75.0||10.9||19||4||4,3,3|
|201||South Anna x (South Anna x JWS 6823)||14||32.1||2||2||5.5||2.3||81.8||10.8||20.4||2,2,1|
|202||South Anna x (South Anna x JWS 6823)||33||42.4||0||1||5||1.3||93.8|
|203||South Anna x (South Anna x JWS 6823)||13||22.1||0||10||3||1.7|
|204||South Anna x (South Anna x JWS 6823)||10||15.2||0||3||4.5||1.5|
|205||South Anna x (South Anna x JWS 6823)||4||8||0||5||2.5||2.0||100.0|
|206||South Anna x (South Anna x JWS 6823)||5||16.7||1||0||5||3.3||100.0||9.7||14.6||3.5||2,1,2|
|207||South Anna x (South Anna x JWS 6823)||13||29.6||0||0||5.5||2.3||72.7||10.2||21.2||4||1,1,1|
|208||South Anna x (South Anna x JWS 6823)||4||10.9||0||1||3.5||2.7|
|209||South Anna x (South Anna x JWS 6823)||10||24.9||0||0||6||2.5||100.0|
|210||South Anna x (South Anna x JWS 6823)||6||15.7||1||1||6||2.6|
|211||South Anna x (South Anna x JWS 6823)||12||28.1||1||0||5||2.3||63.6||9.6||19||3.5||1,1,1|
|212||South Anna x (South Anna x JWS 6823)||6||18.7||0||6||5||3.1|
|213||South Anna x (South Anna x JWS 6823)||10||22.9||0||4||3||2.3||77.8||12.8||20||4.8||2,1,2|
|214||South Anna x (South Anna x JWS 6823)||16||24.6||1||3||4||1.5||100.0||12.7||18.5||4||4,1,4|
|215||South Anna x (South Anna x JWS 6823)||3||9.9||1||2||4||3.3|
|216||South Anna x (South Anna x JWS 6823)||16||33.4||0||0||4.5||2.1||100.0||10.5||19.4||4||4,4,4|
|217||South Anna x (South Anna x JWS 6823)||7||13.6||0||3||3.5||1.9|
|MEDIAN||South Anna x (South Anna x JWS 6823)||10||22.5||0||2||4.5||2.3|
South Anna Breeding Trial - 2020 Twin Oaks Seed Farm (Direct seeded early June)
|Plant Number||Weight of Marketable Squash||Number of immature squash||Plant Area (Sq Ft.)||Yield per 10 square feet||Downy Mildew Rating 9/21 (1-9 scale, 9 is worst)||% of mature squash that are marketable||Percent Keeping Late November||2019 Seed Origin||11-7 Eating Quality Rating||11-7 Dry Matter||11-7 Brix||11-12 Eating Quality Rating||11-12 Dry Matter||11-12 Brix|
Wild Hope Farm Large Block Trial 2020 (Planted 4/14 and transplanted 5/5-5/8)
|Variety||Actual Bed Feet||Acreage||Harvest Date||Tota Yield (bu)||Bushels per 1/8 acre|
Care of the Earth Farm Waltham x San Jose Mountain Squash Breeding Trial - Harvest and Eating Quality Data
|Plant ID||Total # of fruit produced||Brix/Flavor notes||Storage (fall, mid-winter, late winter)||Additional notes/observations|
|M192-4||6||13.5, typical butternut||tasted late fall||butternut|
|M192-5||2||14.6, nutty and caramelly, yum!||tasted late fall||butternut|
|M192-6||3||12.8, typical butternut/12.9||tasted early winter||butternut|
|M191-2||1||14.4, perfect||tasted late fall||butternut|
|M191-3||3||15, really good but small (1#)/13||tasted early winter||butternut|
|M191-7||2||16, sweet, typical butternut||tasted early winter||butternut|
|E1825B-4||3||11.6, nutty, could be sweeter||butternut but SJ markings|
|E1825B-6||3||14.4, absolutely amazing||tasted late fall||butternut but SJ markings|
|E1825-11||1||13.5, typical butternut||tasted late fall||SJ|
|M192-14||2||8, not sweet but flavorful (immature?, not a lot of mature seeds)||tasted late fall||squat butternut|
|L1827-20||3||10.2, not super sweet but really good flavor and creamy texture/12.4||tasted late fall||butternut but SJ markings|
|L1827-15||1||butternut but SJ markings|
|L1827-13||0||butternut but SJ markings|
|L1827-12||2||13.6||butternut, large bulb|
|L1827-5||1||butternut but SJ markings|
|L1827-4||2||butternut but SJ markings|
|T180-3||1||12.2, good flavor||mid-winter||butternut|
|T180-11||3||14, not complex but sweet||tasted 1/20||butternut|
|P1821-5||2||14.6, very sweet, butterscotch flavor||fall, some internal sprouting seeds||SJ|
|L1826-1||5||12.5, really good flavor, seedy||tasted early winter||butternut|
|L1826-7||4||almost butternut (slightly cousa/pear)|
|L1826-23||5||14, “best I’ve tasted”||almost butternut (slightly cousa/pear)|
Breeding and Variety Trials - 2021 Twin Oaks Seed Farm (Direct seeded June 16th) Note that the first 17 entries are blocks of several plants, while the rest (starting with South Anna x Atlas 10-2) are single plants.
|Entry ID||Origin||number of firsts||Marketable Weight (pounds)||Row Feet||Yield per row foot||% of mature fruits marketable at Harvest||number immature at harvest||% Good in Early December||Median Taste Rating (1-5 scale; 5 is best)||Median Brix||Median Dry Matter||Number of tests (taste, brix, dry matter)||Downy Mildew Rating (1-9 scale, 9 is worst)|
|63xSA50||87.5% South Anna; 12.5% Chinese Tropical||8||11.4||15||0.8||57||1|
|200x54||12.5% JWS6823; 25% Guatemalan Green Ayote; 62.5% South Anna||16||43.4||15||2.9||100||1||73||4.5||11.4||15.9||3,4,4|
|200x63||12.5% JWS 6823; 12.5% Chinese Tropical; 75% South Anna||17||36.2||15||2.4||89||1||6||13.1||16||0,1,1|
|61x200||12.5% JWS 6823; 12.5% Chinese Tropical; 75% South Anna||6||23.7||15||1.6||60||0||71|
|54x50SA||75% South Anna; 25% Guatemalan Green Ayote||16||50||15||3.3||84||4||67||1||9.6||12.45||4,5,6|
|50SAx54||75% South Anna; 25% Guatemalan Green Ayote||27||71.3||15||4.8||93||4||83||9.6||13.1||0,3,3|
|200x50SA||87.5% South Anna; 12.5% JWS 6823||23||54.3||15||3.6||85||0||35||2||11.2||13.4||2,2,2|
|GGA 78||Guatemalan Green Ayote||5||8.8||20||0.4||83||10|
|GGA 70||Guatemalan Green Ayote||15||34.8||20||1.7||100||7||75||4.5||12.8||16.5||1,1,1|
|GGA 75||Guatemalan Green Ayote||20||39.6||20||2.0||100||6||40|
|GGA 81||Guatemalan Green Ayote||5||11.4||20||0.6||100||5||20||Extremely Variable|
|CNP15ATOS||Cuban Neck Pumpkin||14||85.1||20||4.3||61||5||60|
|CNP19 Sel 13||Cuban Neck Pumpkin||16||122.8||20||6.1||84||0||6.7||8.5||0,2,2|
|CNP19AMC||Cuban Neck Pumpkin||11||101.9||20||5.1||61||1||9.3||11||0,1,1|
|PI 482506||Zimbabwe via GRIN||7||13.8||12||1.2||88||3|
|(10-2)||South Anna x Atlas||6||26||7||3.7||100||0||100||9.6||12.7||0,1,1|
|(11-1)||South Anna x Atlas||2||6.1||7||0.9||100||0|
|(11-3)||South Anna x Atlas||6||19.1||7||2.7||100||1|
|54-1||South Anna x Guatemalan Ayote||2||8.6||7||1.2||67||2|
|54-2||South Anna x Guatemalan Ayote||8||22.7||7||3.2||100||0||29||5||14.9||20.9||3,3,3|
|54-3||South Anna x Guatemalan Ayote||9||30.4||7||4.3||100||2||75||5||12.9||19.7||2,4,4|
|54-4||South Anna x Guatemalan Ayote||7||21.3||7||3.0||100||0||100||4.5||11||15.4||2,3,3|
|52-1||South Anna x Guatemalan Ayote||9||14||7||2.0||100||3||44|
|52-2||South Anna x Guatemalan Ayote||6||17.4||7||2.5||100||0|
|A||South Anna 75%; Chinese Tropical 25% 63x61||5||17||7||2.4||100||2||80||4.5||12.2||17||1,1,1||5.5|
|B||South Anna 75%; Chinese Tropical 25% 63x61||5||14.3||7||2.0||100||1||60||6.5|
|C||South Anna 75%; Chinese Tropical 25% 63x61||5||19.1||7||2.7||100||0||100||4.25||11.3||14.1||2,2,2||6|
|D||South Anna 75%; Chinese Tropical 25% 63x61||6||30||7||4.3||100||0||80||4.25||11.1||15.2||2,2,2||5.5|
|E||South Anna 75%; Chinese Tropical 25% 63x61||5||18.7||7||2.7||100||1||100||3.5||11.2||15||1,1,1||5.5|
|F||South Anna 75%; Chinese Tropical 25% (61x63)||8||16.6||7||2.4||100||4||71||5.5|
|G||South Anna 75%; Chinese Tropical 25% (61x63)||9||26.5||7||3.8||100||3||89||3||10.4||14.3||1,3,3||6.5|
|H||South Anna 75%; Chinese Tropical 25% (61x63)||7||19||7||2.7||100||0||83||3.5||11.4||14||1,1,1||6.5|
|I||South Anna 75%; Chinese Tropical 25% (61x63)||6||24.7||7||3.5||100||0||100||4.25||11.4||14.3||2,2,2||5.5|
|J||South Anna 75%; Chinese Tropical 25% (61x63)||10||20||7||2.9||100||1||40||7|
|K||South Anna 75%; Chinese Tropical 25% (61x63)||13||25.3||7||3.6||100||1||77||4||11.2||14.2||1,1,1||5|
|L||South Anna 75%; Chinese Tropical 25% 61||14||17.4||7||2.5||100||0||71||6.5|
|M||South Anna 75%; Chinese Tropical 25% 63||7||19||7||2.7||100||0||0||6.5|
|1||Butternut 200 (South Anna 75%; JWS 6823 25%)||22||35.5||10||3.6||100||3||25||15.9||0,3,0||6.5|
|2||Butternut 200 (South Anna 75%; JWS 6823 25%)||8||15.6||7||2.2||100||5||0||5|
|3||Butternut 200 (South Anna 75%; JWS 6823 25%)||14||25.5||7||3.6||93||0||14||4.5|
|4||Butternut 200 (South Anna 75%; JWS 6823 25%)||4||6.4||7||0.9||100||4||4.5|
|5||Butternut 200 (South Anna 75%; JWS 6823 25%)||13||24.6||7||3.5||100||0||23||7.5|
|6||Butternut 200 (South Anna 75%; JWS 6823 25%)||10||19.8||7||2.8||91||2||0||4.5||12.9||15.6||3,3,3||5|
|7||Butternut 200 (South Anna 75%; JWS 6823 25%)||7||11.1||7||1.6||78||3||4.5|
|8||Butternut 200 (South Anna 75%; JWS 6823 25%)||7||15.5||7||2.2||100||6||4|
|9||Butternut 200 (South Anna 75%; JWS 6823 25%)||11||19.7||7||2.8||100||7||4|
|10||Butternut 200 (South Anna 75%; JWS 6823 25%)||10||16.1||7||2.3||100||0||5.5|
|11||Butternut 200 (South Anna 75%; JWS 6823 25%)||10||19.6||7||2.8||100||1||9|
|12||Butternut 200 (South Anna 75%; JWS 6823 25%)||11||18.3||7||2.6||100||3||0||6|
|13||Butternut 200 (South Anna 75%; JWS 6823 25%)||8||19.8||7||2.8||100||2||0||6|
|15||Butternut 200 (South Anna 75%; JWS 6823 25%)||13||23.4||7||3.3||93||0||38||4||1,0,0||7.5|
|16||Butternut 200 (South Anna 75%; JWS 6823 25%)||13||25.9||7||3.7||93||7||42||4.5||10.3||1,3,0||5|
|17||Butternut 200 (South Anna 75%; JWS 6823 25%)||13||17.5||7||2.5||100||5||6|
|18||Butternut 200 (South Anna 75%; JWS 6823 25%)||12||17.6||7||2.5||75||3||7|
|19||Butternut 200 (South Anna 75%; JWS 6823 25%)||10||12.8||7||1.8||63||1||6|
|20||Butternut 200 (South Anna 75%; JWS 6823 25%)||6||9.3||7||1.3||86||1||4.5|
|21||Butternut 200 (South Anna 75%; JWS 6823 25%)||7||8||7||1.1||100||1||4|
|22||Butternut 200 (South Anna 75%; JWS 6823 25%)||20||25.8||7||3.7||100||1||47||4||10.9||14.7||4,3,3||6.5|
|23||Butternut 200 (South Anna 75%; JWS 6823 25%)||8||12||7||1.7||100||1||5.5|
|24||Butternut 200 (South Anna 75%; JWS 6823 25%)||16||24.7||7||3.5||100||0||31||3.5||10.9||12.7||3,3,3||4.5|
|25||Butternut 200 (South Anna 75%; JWS 6823 25%)||13||19.5||7||2.8||100||0||92||4||10.4||13||1,3,3||4.5|
|26||Butternut 200 (South Anna 75%; JWS 6823 25%)||15||22.6||7||3.2||100||2||36||4||10.3||14.7||1,3,3||5|
|27||Butternut 200 (South Anna 75%; JWS 6823 25%)||9||11.7||7||1.7||82||2||8|
|28||Butternut 200 (South Anna 75%; JWS 6823 25%)||16||28.2||7||4.0||100||4||56||3.5||11.4||14.8||1,3,3||7|
|29||Butternut 200 (South Anna 75%; JWS 6823 25%)||12||18.1||10||1.8||92||2||4|
Pictures from Research at Twin Oaks Seed Farm
Educational & Outreach Activities
We hosted a field day on September 21st, 2020 at Twin Oaks Seed Farm in Louisa, Virginia. About 35 farmers, apprentices and farm workers from Broadfork Farm, Shalom Farms and Acorn Community Farm attended. We looked at and talked about the South Anna Butternut breeding trial, large and small block trials, and the diverse squash breeding trial - all located in separate isolated fields at the farm.
On January 28th, 2021, Edmund Frost was part of an online presentation about tropical squash organized by the Culinary Breeding Network as part of their online Winter Squash Week. Co-presenters included Linda Wessel-Beaver of University of Puerto Rico, Glenn Teves of University of Hawaii Extension, and Jay Bost of University of Hawaii. Here's a link: https://www.youtube.com/watch?v=Ec2LNtsbi68
We hosted a field day and plant breeding skill-share on September 14th, 2021 at Twin Oaks Seed Farm. About 30 farmers and farm workers from Broadfork Farm, Acorn Community Farm, Living Energy Farm Belair Farm and elsewhere attended. Jeff McCormack, founder of Southern Exposure Seed Exchange, also shared some about his plant research work.
Candace Pollock from University of Georgia visited and toured the fields at Twin Oaks Seed Farm on October 4th, 2021, and wrote an article that was subsequently published on the SARE website, and in the Acres USA print magazine.
The primary impacts of this project are the improvement and development of new butternut squash varieties adapted to the Southeast and mid-Atlantic regions. This is a long process, but we made good progress with selections in both 2020 and 2021. We have already released two new varieties that result from this project, Butternut 200 and Xiye Butternut, and we expect more will come. We also improved the existing variety South Anna and adapted Guatemalan Green Ayote for our temperate climate. We have 2022 plantings (not funded by SARE) of many of the resulting selections, which continue to offer insight and promise.
At the end of 2021 we released a new experimental variety selected from the population derived from South Anna (75%) and JWS 6823 (25%). The variety has small and fairly uniform 1-2 pound fruit (smaller fruit is desirable for market and CSA growers) with dark tan exterior color, smooth texture, excellent eating quality (with a nutty flavor and high dry matter and brix), good downy mildew resistance, and moderate to good yields. Fruit quality is comparable to 'Honeynut' and could command similar market attention for quality. It is not a long keeper. We're calling it 'Butternut 200' for now but it may get a better name.
At the end of 2021 we also released a new variety called Xiye Butternut, bred at Care of the Earth Community Farm from the Waltham - San Jose Club cross. It appears to be earlier and more determinate than South Anna, which could be helpful to many growers. It has good DM resistance, eating quality and productivity, with medium to large fruit size. A different selection from the initial cross, with smaller fruit and shorter vines, also shows promise.
We've obtained better selections within the South Anna variety - this variety is already popular with many growers in the region. Improving keeping quality and productivity, while retaining eating quality, will continue to be selection goals moving forward.
The crosses derived from South Anna and Guatemalan Green Ayote showed excptional eating quality in 2021 (which was somewhat surprising as eating quality had been moderate in 2020), and most had very good keeping quality as well. They also have exceptional DM resistance.
The crosses derived from South Anna (75%) and Chinese Tropical (25%) are also promising, with improved keeping quality compared to South Anna, good eating quality (one selection has a mango-like flavor), good DM resistance and productivity.
A cross of South Anna (62.5%), Guatemalan Green Ayote (25%) and JWS 6823 (12.5%) is also showing promise, with a good combination of eating quality, productivity and keeping quality. We are crossing it back to South Anna this year - it could be a parent for an improved version of South Anna.
We also made good progress improving Guatemalan Green Ayote for our climate. We have a seedstock growing in 2022 that results from the cross of a deep green (but late and not very productive) selection with a selection that is high yielding and somewhat green-fleshed. It has exceptional downy mildew resistance and very good eating quality.
Another goal was to compare South Anna to leading commercial varieties used in the region. The information gathered was helpful to us in identifying:
-that improving keeping quality in South Anna and derivatives is a need
-that we are doing well on eating quality compared to commercial hybrids
-that South Anna has good DM resistance compared to popular susceptible varieties like Avalon, Metro and Waltham, but that there are other commercial varieties with comparable resistance
Something else that became very clear with this project: Cucurbita moschata squash acts in unexpected and mysterious ways! We continue to be fascinated with these plants and to enjoy the deep relationships we have with them.
Researching and developing butternut squash that is optimal for our region is a long term project. Continuing to compare varieties and new selections and crosses in diverse conditions throughout the Southeast is desirable moving forward.