Diversified Research, Powell research center strives to produce usable researchWritten by Saige Albert
Powell – Wyoming’s Production Agriculture Research Priorities describe their mission as to “enhance the competitiveness, profitability and sustainably of Wyoming agricultural systems,” and the Powell Research and Extension Center (PREC) continues to carry out experiments to meet that goal and improve irrigated farming.
One of the crops of increased focus at PREC is the confection sunflower – a specialty crop that Research Associate Andi Pierson says is increasing in prevalence across the Bighorn Basin.
“Confection sunflower is becoming more commonly grown and an increasingly more important cash crop to Wyoming farmers, especially many in the Bighorn Basin,” writes Austen Samet et al in a summary of sunflower research at PREC.
“With confection sunflowers on the rise, we are pretty excited to have the opportunity to work with SunOpta, Inc. to find the best varieties suited for production here,” Pierson explains.
Confectionary sunflowers, she adds, are those used primarily for food.
PREC has implemented a number of research projects related to sunflower production to answer producer’s questions, including ideal planting date, irrigation rates and varieties.
In looking at a number of sunflower varieties, all planted on May 23 of this year, Pierson notes, “The data we collect includes yield and seed samples.”
Seed samples are sent to SunOpta, Inc. for testing to determine their quality.
“With confection sunflowers, the quality of the seed is key,” Pierson notes. “If they don’t make the right grade, they are not considered confectionary and are sent to be used as birdseed and other things.”
They also determine plant height, days to maturity, test weight, seed yield, seed size and harvest moisture.
“Data collected should provide information needed to identify varieties suitable for production in the Bighorn Basin,” writes Gary Moss, PREC’s interim research leader. “This information could help producers more efficiently raise high-quality confectionary sunflower seeds.”
In addition to determining what varieties perform best, Pierson says they have also introduced some companion crops with the sunflowers.
“We have another project working with Roger Stockton of the Natural Resources Conservation Service,” she explains. “We have planted a companion crop with sunflowers. The mix includes millet, sorghum, radishes and field peas.”
The idea of a companion crop, continues Pierson, is to add organic matter and increase nitrogen in the soil while simultaneously harvesting a crop.
“We are hoping the companion crop works similarly to a cover crop,” Pierson comments.
As is common in irrigated farming, water concerns continue to impact farmers in the Bighorn Basin and throughout Wyoming.
“Although the number of acres put into sunflowers each year has continued to increase, there are still many questions regarding how and when to irrigate to obtain maximum production in the typical growing conditions of Wyoming,” Samet explains, adding that farmers typically irrigate sunflowers every 10 to 14 days.
“Past research has determined that sunflowers are moderately tolerant to water stress and may be an excellent crop for limited irrigation strategies without compromising grain yield and quality,” Samet continues.
The project involved beginning irrigation at three stages – full irrigation (F), when the miniature floral head was observed (R1), when the head began to open (R4) and rain-fed.
Each of the four samples was irrigated uniformly to promote establishment.
The first year of the experiment in 2010 showed similar results between the first three irrigation treatments.
“The results, however, were even more interesting when comparing these three strategies while looking at the total grain yield versus the 20/64 sieve yield,” explains Samet.
The 20/64 sieve yield separates seeds of a larger size.
“The highest average yield in the 20/64 sieve was in the crop under R4 irrigation, then R1, then full,” he says. “Irrigation water from planting may enhance the total amount of grain yield over rain-fed application alone. Our results suggest, however, that irrigation water application beginning at the later stages of sunflower growth may produce a higher percentage of ‘big seeds’ measured using a 20/64 sieve.”
The study is being repeated this year.
In a second, combined study, irrigation impacts were analyzed in conjunction with planting date.
“We planted these sunflowers at various dates stretching from May to the first week of June,” Pierson explains. “Within each section, we have different irrigation shutoff treatments.”
Rather than starting irrigation based on plant stage, as in Samet’s research, Vijaya Joshi et al stopped irrigation at different stages.
“We are running into the problem that sunflower dry-down is taking too long, and we are harvesting too far into the fall,” Pierson says. “We are hoping that if we can limit the amount of irrigation events we have over the year, we can cut down labor costs and have a faster seed dry down time.”
Date and water impacts
Results from 2012 showed significant effects on total yield whereas no effect of 20/64 yield was seen. The next year’s results showed no significant results for either total yield or 20/64 yield.
“Both total yield and 20/64 yield were significantly affected by planting date in the 2012 and 2013 growing seasons,” Joshi writes in a summary of the project. “The highest yield in 2012 was obtained from planting on May 30, while the highest yield in 2013 was obtained from planting on June 10.”
Additionally, Joshi notes that planting from the last week of May to the first week of June and irrigating until the R5.5 growth stage, when the flower is 50 percent emerged, are promising for optimum sunflower production in the Bighorn Basin.
PREC’s researchers will continue to provide real-world solutions to problems that farmers face in the Bighorn Basin, including research analyzing less traditional crops being introduced into the area.