COMPETITIVENESS OF CANADA PRAIRIE SPRING WHEATS WITH WILD OAT (AVENA-FATUA L)

Three spring wheat (Triticum aestivum L.) genotypes (Neepawa, a hard red spring, and HY320 and HY355 both Canada Prairie Spring wheats) were subjected to four levels of wild oat density at two locations over 4 yr to assess the effects of wild oat competition on biomass production, culm formation and yield. Wheat biomass and culm production were reduced at all wild oat density levels in each of the three cultivars. There were no significant differences among cultivars. In general, yields of all cultivars were reduced as wild oat density levels increased. Actual yield reductions at comparable wild oat densities tended to be greater at Regina than at Scott. There was a significant cultivar-by-density interaction for yield with yield reductions in HY320 > HY355 > Neepawa.