By DIPAK SANTRA
Alternative Crops Breeding Specialist,
and DAVID OSTDIEK
Communications, UNL Panhandle Research and Extension Center, Scottsbluff
A graduate student at the University of Nebraska-Lincoln Panhandle Research and Extension Center in Scottsbluff is in the midst of an ambitious project that he and his advisor hope will produce a set of modern tools for genetic improvement of proso millet.
Rituraj Khound has been a grad student under the supervision of Dipak Santra, alternative crops breeding specialist at the Panhandle Center, since 2018. He hopes to receive a Ph.D. in plant breeding and genetics in 2022 from UNL’s College of Agriculture and Natural Resources.
Proso millet is used in the United States primarily for birdseed but also used for human and pet food and livestock feed. In some parts of the world it is grown more widely for human consumption.
According to Khound, proso millet is a good fit for farms in the High Plains because it is a short-season crop that converts water into grain more efficiently than other cereal grains (wheat, corn and barley). Some farmers grow millet as part of a crop rotation where winter wheat is their main cash crop. A warm-season grass, millet is typically planted in late May or early June and harvested in September.
Nebraska, South Dakota, and Colorado are the largest producers of proso millet, and some acreage also is grown in adjacent states, according to a Nebraska Extension Publication, “Producing and Marketing Proso Millet in the Great Plains.” Acreage and production vary considerably from one year to the next. Worldwide, other commercial producers besides the United States include Asia (China, Russia, India, Korea and Japan) and Europe (Ukraine, Hungary, Czech Republic, Slovenia, Poland, Austria and Switzerland).
Khound’s goal of adding to the base of knowledge about millet genetics, developing efficient crop-breeding methods, and using these to breed new, high-yielding millet varieties could make the crop easier to produce, and potentially more profitable, for the existing growers and end users. It would also be one of several steps toward making millet more adaptable to diverse climates and multiple end uses, including on American dinner plates.
Millet grain has important nutrients for human health, with gluten-free, anti-diabetic and anti-cancer properties. Millet is an ancient grain, an attractive quality for many consumers.
Presently Santra is the only public crop breeder working on millet, and doesn’t have the same genomic resources as counterparts who work with major commodity crops such as wheat, corn, and soybean.
Khound’s project is aimed at establishing some of that foundation. It consists of several projects with an overarching goal of developing the modern tools to make proso millet breeding more efficient, precise and cost-effective.
The first project is understanding the genetic principles behind the important agronomic traits. Khound is working on developing molecular markers, which will allow for mapping important genes that control the desirable traits. They also help in assessing genetic diversity of proso millet, making it quicker to predict which breeding lines are likeliest to have the desired traits.
Two such traits are resistance to lodging (laying down) and grain shattering. This project is in collaboration with Janes Schnable, computational biologist and associate professor of plant breeding and genetics, based on UNL’s Lincoln campus.
The second project is to study the diversity in genetics and phenotypes (measurable physical characteristics, such as height) in the U.S. proso millet germplasm. Khound is tapping into an extensive U.S. Department of Agriculture collection of hundreds of proso millet genotypes. Last year they planted 450 genotypes in Scottsbluff and Sidney (at the High Plains Ag Lab) and record 15-20 different plant characteristics for each, including agronomic traits. The ultimate goal is todevelopa database for plant breeders listing all the argronomic traits in detail.
Schnable and Vikas Belamkar, research assistant professor in plant breeding and genetics in the Department of Agronomy and Horticulture, are significantly contributing to this project.
Santra says the database will be used to identify millet lines that will be the source of highly desirable characteristics, which will be used as parent lines in crossing.
Santra said, “At the end of the day we want to have a higher-yielding variety with lodging and shattering resistance. We also want to understand the genetic architecture – we plan to do genome sequencing of the entire collection.”
The third project will check the feasibility of using digital images obtained with unmanned aerial vehicles (UAVs, or drones) as a source of “high-throughput phenotyping.” With assistance from Bijesh Maharjan, the soil and nutrient management specialist at the Panhandle Center, the proso millet plots will be systematically photographed using drones. These images will be correlated to measurements taken in the fields and laboratories, to see whether the drone images can be analyzed to gather the same phenotype data as field and lab observation. If so, using drones would require much less field labor and cost to generate the data.
Yeyin Shi, assistant professor in the Department of Biological Systems Engineering, is helping this project in image analysis and extracting trait data to be matched with field-based data.
Proso millet is a crop with a long history and a list of potential benefits, according to Santra and Khound. Khound said it was domesticated 10,000 years ago in China, before either wheat or rice, and spread to other parts of the world. It is an important part of the human diet in China, India, Russia, and other parts of Asia, as well as Africa.
Santra said millet was brought to America in 1877 by Germans from Russia, some of whom settled in the North Platte Valley around Scottsbluff. The Germans from Russia also brought another crop that became an agricultural mainstay of the area, Turkey Red, the first winter wheat introduced to the United States. Prior to that time, spring wheat was the most common crop.
Millet lost out to other grains such as wheat and corn in the fields and diets of America, and gradually its primary use became animal feed. But other livestock feedstuffs – corn, soybeans, and barley – could be produced in high volume more cheaply than millet, which now is primarily grown in the United States for wild bird feed. The bird seed industry does not require the same volume as livestock feed.
But Santra said proso millet is still used as food primarily in Asian countries, where it originated.
A similar dietary evolution occurred in Europe. Once common in the diets of Europeans in Poland, Austria, Switzerland, Slovania, Italy, and France, millet was gradually replaced by corn, wheat, soybean, and mustard, as agricultural research developed.
But in Europe, and now in America, a segment of consumers is choosing foods according to a preference for health, nutritional value and the food’s origins. They look for labels such as ancient grains and gluten-free, and also for health and nutritional qualities. Santra said proso millet is a source of starch that is healthier for people with starch-related metabolic disorders such as Type II diabetes; high levels of minerals essential for human health (such as iron and calcium); and chemicals believed to be beneficial for preventing hypertension, high cholesterol levels, and cancer.
“It is healthy for the environment; it is healthy for humans,” Santra said. “These are the two major attributes in favor of growing millet.”
To increase the share of American millet production that goes to human consumption, Santra said it will require improved varieties, produced by modern breeding techniques that Khound is helping to develop. Higher-yielding varieties with larger seed size and improved agronomic traits also will benefit the current markets – be they bird seed, food products such as beer and whiskey, or livestock feed.
But better plant breeding isn’t the only necessary growth factor. There’s also farm policy – proso millet does not have a checkoff program, like some other major crops such as wheat and corn, to generate revenue for research and marketing. And food-processing companies would need to be willing to use significant amounts of millet in their food products.
Khound says developing high-yielding proso millet varieties for diverse climates and multiple end uses could help generate more interest in proso millet research and large-scale commercial production, which in turn would strengthen the economy of rural Nebraska and the High Plains.