Potential Causes of Yield Instability in Annual Canary Grass.

Annual canarygrass or canaryseed (Phalaris canariensis) originating from the Mediterranean region and Middle East suffers from unstable grain yield to a greater extent than other temperate cereals when grown under the long days and variable weather conditions typical of the Canadian prairies. The recent approval for human consumption will provide a market opportunity for canaryseed that requires sustainable grain production.

This study compared differences in biomass, grain yield and yield components among two temperate cereal species adapted to the western Canadian environment and canaryseed with the objective of providing a better understanding of the factors responsible for the relatively larger swings in canaryseed grain yield.

Three canaryseed cultivars were compared to a spring wheat and an oat cultivar in field experiments at three seeding dates (early, late and very late based on local seeding time practices) in 2012, 2013 and 2014.

Biomass variability of canaryseed cultivars amongst year×seeding date combinations (1.8-fold) was similar but slightly higher compared to that of wheat (1.5-fold) and oat (1.4-fold) cultivars. However, grain yield and harvest index variability of canaryseed cultivars was between two and three times that of the other species cultivars.

Canaryseed inflorescence and kernel numbers per m² were the yield components which exhibited the greatest variability (ca. 3-fold). That was approximately twice the variability shown by the other two species cultivars in both variables.

Grain yield derived from tillers of canaryseed cultivars accounted for 36-85% of whole plant yield compared to 19-48% and 6-34% for wheat and oat, respectively.

Canaryseed grain yield showed more variability and was more tiller-dependent than wheat and oat. These observations suggest that growing conditions less favorable for tillers to reach physiological maturity may have a larger impact on grain yield of canaryseed compared to wheat and oat cultivars.