Pee Dee Research and Education Center researchers working to develop field peas and sorghum varieties

March 10, 2019

New research at the Clemson University Pee Dee Research and Education Center seeks to offer South Carolina farmers alternative crops with increased nutrition and commercial viability.

Funded by a nearly $1 million grant from the U.S. Department of Agriculture, the three-year research project will attempt to develop field pea and grain sorghum plant varieties, known as cultivars, that can be grown organically while increasing crop yield and nutritional quality.

Project director Dil Thavarajah said consumer demand has increased for organic plant products, especially in allergen- and gluten-free markets. However, current organic grain production depends on varieties that have been bred for non-organic production, and these are often not suited to organic production.

“Organic systems don’t have as many soil nutrients as conventionally grown foods,” Thavarajah said. “Therefore, organic crops can have reduced yields and lack protein, prebiotic carbohydrates and micronutrients. We believe pulse crops like field peas show great potential for biofortification.”

According to the World Health Organization website, biofortification is the process by which the nutritional quality of food crops is improved through agronomic practices, conventional plant breeding or modern biotechnology. Biofortification differs from conventional fortification in that biofortification aims to increase nutrient levels in crops during plant growth rather than through manual means during processing of the crops.

Thavarajah said very little science has been done with respect to reducing the yield gap or developing genomic tools for selecting both field pea and sorghum cultivars with increased nutritional quality for organic farming systems.

Rick Boyles, research scientist at the Pee Dee Research and Education Center in Florence and Darlington counties, has a background in plant breeding and genetics and leads sorghum research for the project. He said technological advancements have rapidly evolved to allow the research team to collect a lot more data to guide in selecting varieties.

“We have thousands of breeding lines to evaluate, so we need to do it as fast as possible,” Boyles said. “We’re looking at primary traits like yield and disease resistance as well as quality traits like protein content. The old way to develop new cultivars was to cross two parent varieties together and look at the progeny.

“Now we use a lot of genetic tools to figure out which gene in the DNA makeup of plants are beneficial. We’re also using automated phenotyping technology to observe and manage plants in the field.”

By selecting the best field pea and sorghum cultivars for the region, the researchers could develop a new cropping system for South Carolina farmers. Field peas, a new Southern cash crop, can be planted in late December to mid-January, with the crop then harvested just in time for planting sorghum.

Along with a sustainable crop rotation, the two crops also help each other succeed. Boyles said sorghum produces weed suppressant chemicals that help field peas thrive. Also, since organic farming restricts synthetic fertilizer use, the nitrogen put into the soil by field peas benefits sorghum.

As the quality of the available cultivars increase and the crops grow in popularity, there are potential uses outside of the organic food market. The field peas could be used to make protein powders and the sorghum could provide an alternative for livestock feed.

“We import hundreds of thousands of bushels of feed grain into the Southeast every year,” Boyles said. “Sorghum is an excellent crop for the South, because of its high productivity and stress tolerance. On sandy soils, the old joke is that we’re always a week away from a drought. High-draining soils don’t hold moisture, and sorghum responds better than corn in those conditions.”

Thavarajah said test plots on farms across the state will help the team identify crop varieties that succeed in different conditions, but there will be more questions to answer as the project develops.

“There are a lot of unknowns and questions we will answer this year,” Thavarajah said. “By spring next year, we will know a lot more. Within a three-year time period, we hope to have varieties selected, but this is a never-ending process. I’m very excited about this project, and I think we’re up to a very good start.”