Developed in the United States in the 2000s, kernza is a perennial cereal combining grain and fodder production. In France, a national observation network for this crop, made up of 25 farmers, was set up in 2020 by a research team from Isara (1). The profiles are multiple (cereal farmers and breeders in conventional or organic), with potentially variable technical itineraries from one farm to another due to references that are still limited in France and Europe. The performances were evaluated by measuring the biomasses produced and the main components of grain yield.
It emerges from the first year of experimentation that the establishment of kernza is particularly delicate, in particular vis-à-vis weeds or associated cover crops established by breeders in the perspective of fodder development. The right choice of plots and a technical itinerary adapted to control this potential competition are therefore essential.
For plots that were able to go through to harvest, “biomass yields ranged between 2 and 10 t of dry matter per hectare and 1 to 15 q/ha for grain”, indicate the researchers. To exceed the threshold of 9 q/ha (economically viable under North American market conditions), early sowing seems necessary between September 15 and October 1st at the latest.
Additional work is planned on densities and cropping practices optimizing grain production in the first year of establishment and the following years.