Selecting wheat cultivars for organic production

Organic crop production systems produce a soil and weed environment different from that found in conventional crop production systems. Arbuscular mycorrhizal fungi (AMF) are important in organic cropping systems for assisting in the uptake of phosphorus from the soil. Due to the differing environments found between organic and conventional cropping systems it is suggested that crop performance could be improved in organic systems if cultivars were selected for organic growing conditions. Three studies were performed in 2007 and 2008 to examine wheat cultivar selection for organic crop production. The first two studies were carried out at two organically managed research sites in Southern Manitoba. The first study compared the hyphal, arbuscular and total AMF colonization of 26 hard red spring wheat lines. Percent colonization by AMF differed among wheat cultivars and between four of the parental combinations at one location. The second study compared AMF colonization and yield between modern and heritage spring wheat cultivars. At two of four site years modern cultivars had higher levels of colonization than heritage varieties. At one site year modern varieties yielded significantly higher than heritage varieties. No differences were found at the other site years. The third study compared yield, protein concentration and kernel weight of seven populations of wheat selected in both organic and conventional environments. The organic and conventionally selected populations were compared at four organic and four conventionally managed locations in Manitoba and Saskatchewan. Selection environment was found to affect yield, protein and kernel weight in both management environments. Direct selection in organic environments for organic agriculture was found to be superior to indirect selection in conventional environments.