Perennial grains have potential economic benefits from grain and forage production as well as environmental benefits derived from long-term soil coverage without tillage, extensive fibrous root systems that sequester organic matter, and the ability to recycle plant nutrients.

In previous issues of Crop News, we have written about Kernza intermediate wheatgrass, a perennial grain in the article, Agronomic advances in Kernza research. Kernza has been evaluated in Minnesota for over 10 years and a plant breeding program has developed new improved varieties. It is now grown and marketed by producers in Minnesota and surrounding states; however, they have been discouraged because grain yields are best in the first 2 years following establishment and afterwards decline as the stands mature. This decline is in part due to competition for resources among plant tissues as Kernza partitions significant amounts of energy into developing underground stems (rhizomes) and an extensive root system instead of grain.

Now through support of the University of Minnesota Forever Green Initiative and the Minnesota Department of Agriculture, a new perennial grain, perennial cereal rye (PC-Rye) is being developed as a dual-use crop to produce both forage and grain in Minnesota while providing environmental benefits.

Perennial cereal rye was first developed by German scientists in the 1960’s by crossing the winter annual cereal rye (Secale cereale) with a low grain yielding, short stature wild perennial rye (Secale montanum). Wild perennial rye is native to a wide region from the Mediterranean to Pakistan and has an overall much greater winter hardiness than widely cultivated winter cereal rye. The plants resulting from this initial cross breeding of the annual x perennial plants were then bred again with annual rye to increase grain yields while maintaining perennial characteristics.

The first modern PC-Rye breeding efforts took place in Canada where multiple breeding cycles were successfully completed to select for winter survival, grain yield, disease resistance. This resulted in the release of the variety ACE-1 by Agri-Food Canada in Lethbridge as a spring silage crop with higher biomass yields than spring barley or winter rye, but as expected, lower grain yields than winter rye. Forage quality of ACE-1 silage was somewhat lower than for spring barley. Some varieties of PC-Rye are reported to produce approximately 73% grain compared to annual rye.

The University of Minnesota’s PC-Rye breeding program initiated in 2022 is the only one in the USA evaluating and improving PC-rye as a dual use crop for grain and forage production. Using plant genetics materials from Agri-Food Canada in Lethbridge and the USDA seedbank in Idaho, Dr. Bajgain is using conventional plant breeding along with modern genetic, genomic, and phenomic tools to accelerate breeding progress and develop new varieties. After only two cycles of selection, he has seen improving perenniality, grain and biomass yield, and lodging resistance. Statewide yield trails will be conducted in 2025-26, and he is optimistic that the first variety will be available in spring 2027.

Photo 1. Perennial Cereal Rye heads at maturity in a field in St. Paul, MN in July 2024. Plots were established in September 2023. Photo taken on 07-16-2024.

Photo 2. Perennial cereal rye accessions in a spaced-planted breeding nursery in St. Paul, MN in May 2024. Plots were established in September 2023.

Photo 3. A side-by-side view of Kernza (left) Perennial Cereal Rye (right) at St. Paul, MN in late October following planting in mid September. Kernza planting rate was 15 lb/ac and rye planting rate was 50 lb/ac.

Photo 4. Seed of winter cereal rye, perennial cereal rye, and Kernza. Perennial cereal rye seed weighs only about 40% of the weight of winter cereal rye.

Photo 5. Seedheads of annual winter rye (left) and perennial cereal rye (right).