Choosing the right oat variety can have a major impact on revenue per acre as it will affect the productivity and marketability of the grain produced. Because chemicals are not used to control weed and pests in organic farming, the choice of variety constitutes an even more important farm management decision than for conventional farming systems. Although oat variety recommendations are available for conventional management system from several public variety testing programs, very limited information on variety performance under an organic production system is available. To guide organic farmers when making variety selection decisions, our goal was to evaluate and compare the performance of twenty oat varieties by performing variety trials at organic farms located in three states within the North Central Region during two growing seasons.
Our objectives were to:
1) Identify oat varieties that will provide the best profitability for organic producers in the North Central region.
2) Identify oat varieties that exhibit good end-use quality so that organic grain produced meets market requirements.
3) Identify oat varieties that can compete with weeds.
4) Communicate results with growers throughout the region by publishing results on extension websites of three universities, presenting at field days in the three states, and presenting at one regional meeting/conference.
Twenty oat varieties (Table 1) were selected with the input of producers, oat breeders, organic seed companies, and the milling industry. The selected varieties were either varieties currently grown by organic farmers, varieties recommended by the milling industry, or varieties recently released. In addition, two entries (Oravena and OT8006) were included because they were specifically developed under organic production system by Agriculture and Agri-Food Canada.
Table 1. List of varieties.
|Entry||Origin||Year of release|
This SARE partnership grant involved the input and participation of three organic producers:
– Jesse Hall from Arlington, SD who was transitioning to organic no-till;
– Mark Doudlah, organic farmer in Evansville, WI;
– and Carmen Fernholz, organic farmer in Madison, MN.
A variety trial was conducted on each farm in 2017 and 2018. In 2017, one of the trials could not be harvested at one of the sites. Therefore, in the second year of the project each participating university conducted an additional trial on land certified for organic production at one of their respective experimental farm sites to ensure that enough data would be collected to reach project objectives. The sites are described in Table 2. In 2018, an excessively wet spring significantly delayed planting and resulted in high weed pressure at some of the sites. The site in Beresford, SD was lost due to flooding in June.
Table 2. Description of trial locations.
|Location||Year||Previous crop||Planting date||seed/
|Under-seeding||Harvest date||Comments on growing season|
|Arlington, SD||2017||Rye||04/22/17||28||Medium red clover (10lb/acre)||08/07/17||Lack of moisture in June. No crown rust.|
|Evansville, WI||2017||Peas||04/18/17||31||None||07/31/17||High weed pressure|
|Madison, MN||2017||soybean||4/17/17||28||red clover||Not harvested||Very high weed pressure|
|Arlington, SD||2018||Hairy vetch||05/05/18||28||Medium red clover (10lb/acre)||08/16/18||High weed pressure.|
|Evansville, WI||2018||Peas||05/07/18||31||None||07/31/18||Planted late due to wet spring. Heat stress (>90s) in late May. Yields were affected.|
|Madison, MN||2018||Soybean||5/1/18||28||Red clover||Not harvested|
|Beresford, SD||2018||Soybean||05/29/18||28||Alfalfa||Not harvested||Extremely wet spring resulted in late planting. In addition, part of the field flooded in June.|
|Madison, WI||2018||Vegetables||04/24/18||31||None||07/27/18||Heat stress (>90s) in late May. Two strong storms caused high lodging and difficulty in harvesting the trial.|
Agronomic data collected during the growing season and end-use quality characteristics collected on harvested grain samples are described below.
Heading date: Julian calendar date on which 50% of the panicles in the plot were emerged.
Canopy height: a ruler was placed randomly into the plot and a reading taken to indicate average height of the canopy.
Lodging incidence: Percentage of plants in a plot that are lodged.
Lodging severity: Severity of plant lodging observed in a plot on a scale from 0 (no lodging) to 9 (all plants are lodged).
Crown rust severity: Percentage of the area of the leaf occupied by crown rust.
Plump: proportion of grain by weight remaining on top of a 5.5/64*3/4 inch sieve.
Mid: proportion of grain by weight remaining on top of a 5/64*3/4 inch sieve but passing through 5.5/64*3/4 inch sieve.
Thins: proportion of grain by weight passing through a 5/64*3/4 inch sieve.
TKW: weight in gram of 1000 kernels.
Groat percent: proportion of groat by weight in grain measured with a Codema dehuller.
Protein content: groat protein content measured with a NIR instrument.
Beta-glucan content: groat beta-glucan content measured with a NIR instrument.
Oil content: groat oil content measured with a NIR instrument.
In addition, because weeds are a major issue in organic production, the farmer at the Arlington, SD location was interested in determining if some oat varieties were better at competing against weeds. In the first year of the project, the crops and weed biomass where determined around Feekes 11.1 by cutting 0.25 m2 in each plot and separating the weed from oat and clover at that location. Plant samples (oat, clover, and weeds) were dried at 65 degree Celsius, and dry matter weight was collected for each sample.
Oat biomass: dry weight of oat in grams from a 0.25 m2 cutting in the plot at 0.5 inches from the soil when oats were around growth stage Fekes 11.1.
Clover biomass: dry weight of clover in grams from a 0.25 m2 cutting in the plot at 0.5 inches from the soil when oats were around growth stage Fekes 11.1.
Weed biomass: dry weight of weeds in grams from a 0.25 m2 cutting in the plot at 0.5 inches from the soil when oats were around growth stage Fekes 11.1.
Jesse Hall’s farm, Arlington, SD
At the South Dakota location, the 2017 growing season was characterized by lower moisture than normal from June to harvest. The field was in the third year of transition for organic certification. Averages for the different traits measured during the 2017 growing season are presented in Table 2. Excessive weed pressure in 2018 resulted in poor grain yields and a CV >20% (data are not reported).
In 2017, average grain yield ranged from 74.8 bu/acre for Hayden to 26.0 bu/acre for Reins with a trial average of 60.9 bu/acre. No fertilizer was applied during the growing season. Based on a soil test performed at the beginning of the growing season, the amount of nitrogen in the soil (22 pounds/acre) was much lower than recommended for oat production. Plots of the variety Reins were severely damaged by rodents which explains its low yield performance in this trial.
Average test weight ranged from 32.2 lb/bu for Reins to 37.4 lb/bu for Rockford. Varieties with high test weight included Rockford, Hayden, Antigo, Goliath, Leggett, Sumo, and Natty.
Table 2. On-farm oat variety trial under organic management, Arlington, SD, 2017.
|Variety||Heading (Julian date)||Height (inches)||Yield (bu/acre)||Test weight (lb/bu)||Oat biomass (g)||Clover biomass (g)||Weeds biomass (g)|
A 0.25 m2 area was cut at about 0.5 inch from the soil surface around growth stage Feekes 11.1. Oat plants were separated from weeds and clover. Oat biomass was significantly different among varieties. The breeding line OT8006 had the highest plant biomass while Reins had the lowest. There was a significant effect of variety on weed biomass with Leggett having the least weed biomass and Antigo having the highest weed biomass. Plant height and oat biomass were not significantly correlated with weed biomass. However, there was a significant negative correlation between weed biomass and heading date. There was no significant effect of variety on the clover biomass, likely because the clover was relatively small at Feekes 11.1. The effect of variety on clover biomass should likely be evaluated at a later stage of clover development.
Mark Doudlah’s farm, Evansville, WI
Averages for traits measured during the 2017 and 2018 growing seasons are provided in Table 3.
Table 3. On-farm oat variety trial under organic management, Evansville, WI, 2017 and 2018.
|2017||2017||2017||2018||2-year average||2017||2018||2-year average|
In 2017, grain yields ranged from 129.5 bu/acre for Deon to 72.3 bu/acre for Oravena. In 2018, yields were lower than 2017, ranging from 77.7 bu/acre for Betagene to 22.8 bu/acre for Rockford. Overall, the highest yielding cultivars were Betagene, Deon, and Saddle. Test weight ranged from 38.5 lb/bu for Antigo to 28.6 for OT8006. Antigo (38.5 lb/acre) and Sumo (37.3 lbs/acre) exhibited excellent test weight with good yield potential.
University of Wisconsin, Madison, WI
Data collected in Madison is reported in Table 4. Yields are not reported due to high variability (CV > 20%). Crown rust infections were present at that site and the severity for each cultivar is reported. In susceptible cultivars, infection with crown rust can cause severe yield loss and significantly reduce test weight. Because conventional fungicides can’t be applied in organic production, it is recommended to choose a cultivar resistant to crown rust. Antigo, Deon, Leggett, Saddle and Sumo are cultivars with good levels of resistance to crown rust (Table 4).
Table 4. Oat variety trial under organic management, Madison, WI, 2018.
|Crown rust severity
University of Minnesota, Lamberton, MN
Table 5. Oat variety trial under organic management, Lamberton, MN, 2018.
|Cultivar||Heading (Julian date)||Height (inches)||Lodging (1-9)||Yield (bu/acre)||Test weight (lbs/bu)|
Grain yield ranged from 90.4 bu/acre for Betagene to 35.5 bu/acre for Leggett. Test weight ranged from 37.7 lb/bu for Sumo to 30.4 lb/bu for Rockford. Similar to the Evansville site, the top two highest performing cultivars for grain yield were Betagene and Deon, with Deon having higher test weight than Betagene.
End-use quality characteristics
Grain quality characteristics are important for marketing organic grain to the milling industry. Grain quality characteristics were collected on samples from Arlington, SD and Evansville, WI in 2017, and from Lamberton, MN, Evansville, WI, and Madison, WI in 2018. The average for each variety over all five environments is reported in Table 6. Grain with a high thousand kernel weight, a high proportion of plump kernels and a low proportion of thin kernels is desirable for milling. Betagene, Oravena, and Sumo produced grain with thins under 5 % and plumps over 50%. Antigo, Newburg, Rockford, Saber, and Souris had a high proportion of thins in their grain (>15%). Thousand kernel weight ranged from 40.1 g for Oravena to 25.6 g for Antigo. The hull covering the groat in oat grain is removed as a by-product during the milling process. Varieties with high groat percent will result in higher milling yield and are therefore more desirable for the milling industry. Groat percent ranged from 67.2% for Saddle to 55.1% for OT8006.
High protein and beta-glucan contents are desirable for nutritional quality. Groat protein content ranged from 17.2% for Antigo to 13.3% for Hayden. Betagene and Natty had the highest (5.5%) and lowest (3.8%) groat beta-glucan content, respectively. Groat oil content ranged from 6.5% for Rockford to 3.8% for Natty.
Table 6. Average end-use quality characteristics for 20 oat cultivars evaluated under organic management in MN, SD, and WI.
|Cultivar||Plumps (%)||Mids (%)||Thins (%)||Thousand kernel weight
|Groat (%)||NIR Protein (%)||NIR Beta-glucan (%)||NIR Oil (%)|
Objective 1: Identify oat varieties that will provide the best profitability for organic producers in the North Central region.
Based on these trials, varieties that are recommended for organic production include Betagene, Deon, Saddle, Antigo, and Sumo. Betagene, Deon and Saddle had the highest yield potential. Test weight for Betagene was low and may be a limitation for meeting the test weight requirement set by the industry. On the other hand, Antigo and Sumo had excellent test weight. Saddle has excellent straw strength. Deon, Saddle, Antigo, and Sumo exhibited good levels of crown rust resistance. Saddle, Antigo and Sumo are early-maturing cultivars while Betagene and Deon are mid- to late-maturing cultivars. The two cultivars from Canada specifically developed for organic production were very late (especially OT8006) and are therefore not recommended for production in this region.
Weed management of variety trials under an organic system is more complex than in conventional systems. In several of the trial locations, experimental error for yield was too high to use the data for making recommendations. Only 4 environments over 3 states were used to evaluate yield performance. While the trials performed as part of this grant resulted in valuable information, the evaluation of cultivars under organic management system should continue over several years to fully evaluate cultivar stability and to develop recommendations for specific production areas in the region.
Objective 2: Identify oat varieties that exhibit good end-use quality so that organic grain produced meets market requirements.
For the milling industry, grain specifications generally include a minimum test weight and a maximum amount of thins. Antigo, Sumo, Saddle, and Deon are likely to meet the test weight requirement. Fan speed can be increased on the combine to increase test weight if necessary. The percent thins was 10% or below for Deon, Saddle, and Sumo while Antigo was characterized by high levels of thins. Betagene had excellent beta-glucan concentration. Antigo and Sumo had high protein content. Sumo exhibited excellent milling quality characteristic, but beta-glucan content was low.
Objective 3: Identify oat varieties that can compete with weeds.
Based on the trial performed on Jesse Hall’s farm, varieties with lower weed biomass (potentially higher ability to compete with weed) included Goliath, Newburg, Oravena, Rockford, and Leggett. Those cultivars are leafy and late-maturing.
Because the weed biomass study was done at only one site-year, it would be necessary to repeat this experiment in order to confirm these results.
Objective 4: Communicate our results with growers throughout the region by publishing results on extension websites of three universities, presenting results at field days in the three states, and presenting at one regional meeting/conference.
An extension publication was developed and was published on the extension website of South Dakota State University (https://extension.sdstate.edu/sites/default/files/2019-05/P-00107.pdf). Print-outs of the extension publication will be distributed at field days in the three states.
Educational & Outreach Activities
An extension publication was developed and will be made available on the extension website of all three universities. Print-outs of the extension publication will be distributed at field days in summer 2019.
By identifying oat varieties that are best adapted to organic production, this project will help organic farmers in the North Central region maximize oat productivity and marketability. Based on the results from a survey sent to organic farmers at the beginning of the project, a relatively high proportion of the respondents were using old varieties. The results from the trials will guide organic farmers in choosing the best oat variety for their operation.