Differences in Canopy Development and Components between Annual Canarygrass and Spring Wheat As Related to Seeding Dates.

Annual canarygrass (Phalaris canariensis) 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. Recent approval of the crop for human consumption will provide it a market opportunity that would benefit from a stable grain production.

The study’s objective is to investigate whether the putative vernalization requirement of the crop may impact the entire and/or individual pre-anthesis phases duration, canopy development and its components as all three characteristics may be relevant to the relatively large swings in annual canarygrass grain yield.

Two canaryseed cultivars along with a spring wheat cultivar were exposed to different air temperatures under a long photoperiod by means of contrasting seeding dates (early and late based on local seeding time practices) in field experiments in 2013 and 2014.

Delayed seeding postponed, in terms of thermal time, annual canarygrass phenological stages such as first Floral Primordium (FI) and Terminal Spikelet (TS) initiation and eventually delayed anthesis. In contrast, estimated timing of TS and anthesis in wheat was either stable or relatively less delayed with late seeding, even when its FI was estimated substantially delayed. Changes in the canaryseed pre-anthesis phenological phases were related to the main shoot Final Leaf Number (FLN) but not to the average phyllochron.

Annual canarygrass FLN was positively correlated with the onset of its stem elongation which, in turn, was negatively correlated with the timing of tillering cessation. Whereas in wheat, the latter was more related to the fraction of PAR intercepted by the canopy.

The putative vernalization requirement of annual canarygrass impacts its development and canopy components greater or differentially compared to the spring wheat cultivar used.