Triticale, A Hybrid Of Wheat And Rye, Eyed As Economical Cover Crop For Louisiana
OLIVIA MCCLURE
BATON ROUGE, LOUISIANA
In Europe, triticale – a hybrid of wheat and rye – is prized as a high-yielding, resilient crop that can be used for livestock feed and bioenergy production. Although less common in the U.S., triticale has been embraced by some as a winter cover crop, and LSU AgCenter breeders are hoping to soon release a variety that is ideal for Louisiana farmers.
Triticale is a vigorous grower that can crowd out winter weeds and protect soil from erosion. It is less prone to falling over and produces much higher yields than rye.
“The hope is that for a lot of folks, especially in northern Louisiana, who have switched over to using rye as a winter cover crop, triticale can be subbed in as a cheaper replacement that’s more productive,” said Noah DeWitt, who along with Steve Harrison is leading the AgCenter’s efforts to develop Louisiana-tailored triticale varieties.
Triticale – pronounced trit-uh-kay-lee – gets its name from Triticumand Secale, the Latin names of its parents. Wheat and rye have different numbers of chromosomes, so like a mule, triticale is naturally sterile – as Scottish botanist A.S. Wilson found out when he made the first wheat-rye crosses in the 1870s.
It wasn’t until 1937 that scientists realized a chemical called colchicine could double triticale’s chromosomes and create fertile plants. That discovery set in motion breeding efforts, and by the 1970s, commercial triticale varieties hit the market.
Triticale has been most widely adopted in Europe; about 90% of the world’s triticale is grown in Poland, Germany and France along with China. While it’s typically used in cattle and poultry rations and ethanol, people can eat triticale, too – although its lower gluten content makes it better suited for things like pancakes and unleavened baked goods than for traditional breads.
DeWitt and Harrison have been evaluating numerous previously developed triticale breeding lines to see whether they are suitable for Louisiana. They’re hoping to release a variety of their own soon.
“At the same time, we’ve begun making new crosses between those lines with the hopes of releasing more lines down the road,” DeWitt said.
In their studies, the breeders have found a lot to like about triticale. Besides its weed suppression benefits, triticale has a strong root system that guards against erosion — an important characteristic for Louisiana farmers, many of whom plant their crops on raised beds that often have to be “rowed up” again before spring planting.
“You don’t want that raised bed to fall apart over the winter as you get rained on, as you get erosion. You can see how the roots of that plant help hold onto that soil,” DeWitt said as he held a triticale plant pulled from one of his and Harrison’s experimental plots at the AgCenter Doyle Chambers Central Research Station in Baton Rouge.
Triticale offers some clear advantages over rye, which is a popular cover crop, DeWitt said. Rye grows tall and can lodge, or fall over, easily. Some commercial varieties mature early, making them susceptible to late-season freeze damage, and are lower yielding than other small grain crops like wheat, oats and triticale.
“If it costs more to get a certain amount of seed out of a certain amount of acreage, that cost gets passed on to farmers,” he said. “If you’re buying that seed for cover crops, you need that seed to be cheap. You can’t charge the same price as wheat or corn for cover crop seed.”
DeWitt and Harrison started working on triticale about four years ago using germplasm from a discontinued breeding program at the University of Florida, where scientists were aiming for an early-maturing variety that would provide silage for dairy cattle in the winter.
The AgCenter program, which focuses on cover crop applications for triticale, is using parental lines from Florida, California, Maryland and Oklahoma to come up with a variety that’s perfect — or close to it — for Louisiana.
Harrison described what that variety would look like: “The perfect triticale variety has a very, very aggressive, deep root that will hold soil. It has a high, early biomass production. It produces a lot of vegetation, a lot of leaf matter that not only adds organic matter to the soil but also can serve as a livestock feed. And you want it early enough so that it outcompetes weeds in the early spring and the winter, but you don’t want it so early that it’s shoulder high by the first of April. You’re looking for that sweet spot in maturity where it gets up to maybe knee high by the first of March and can be terminated and is easy to plant the next crop into.”
Another part of the variety development process is addressing growers’ hesitations about triticale. Maturity is a key consideration, as varieties that flower too soon are at risk of freeze damage.
A second major concern is the cost of termination – the process of killing a cover crop, usually with herbicide, prior to planting a cash crop.
“You don’t want to have to apply with a super heavy rate because you want it to be economical, and it also has to be quick, and it has to be a 100% kill rate,” DeWitt said. “You don’t want something that’s hanging around for weeks after herbicide has been applied to it, and you don’t want something like a 90% kill rate where you still have plants that will come back and interfere with your primary crop.”
With help from AgCenter weed scientist Stephen Ippolito, DeWitt and Harrison are studying how triticale responds to glyphosate and whether application timing needs to be adjusted.
“The answer I would love for that is triticale is just as sensitive as rye to glyphosate application,” DeWitt said. “If not, then that’s something we can adopt as a breeding program target.” ∆
OLIVIA MCCLURE
LSU AGCENTER