Submitted to: NCR-167 Corn Breeding Committee Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/21/2005
Publication Date: 2/21/2005
Citation: Golden, J.C., Pollak, L.M., Goldstein, W., Lamkey, K.R., Exner, D. 2005. Evaluation of corn germplasm for sustainable agriculture: the 2004 season. NCR-167 Corn Breeding Committee Meeting. Available: http://corn2.agron.iastate.edu/NCR167/Meetings/2005/2005NCRAgenda. Interpretive Summary:
Technical Abstract: Demand for organic products has been increasing at a rate of 20% a year. Because of this, producers involved in organic and low input corn production have shown great interest in genotypes that will perform well in these systems, increase profitability, have good nutritional quality, and lower input costs. In 2003 USDA initiated a breeding project to meet these needs. The project identifies and develops corn cultivars well adapted for sustainable systems, and identifies sources of germplasm high in protein and favorable amino acid balance to incorporate into corn cultivars that will increase producer productivity, profitability, and sustainability. The project is a participatory, cooperative effort between producers and breeders. Farmers are involved in yield trials, and on-farm selection and breeding. Farmers growing yield trials use various rotational regimes, from a typical corn-bean rotation, to a three to seven year rotation involving corn, bean, small grain, legumes, and compost. The project evaluates material from USDA/ARS, GEM, Iowa State University, Michael Fields Agricultural Institute, and private for performance in conventional and sustainable agronomic systems, for selection and breeding in both conventional and sustainable systems for comparison. This report is a summary of the 2004 yield trials. The trials consisted of five experiments in twelve locations (two were abandoned). A sustainable versus conventional experiment compared 10 varieties and hybrids at an organic and a conventional location. There were significant differences among entries for yield, and a highly significant genotype by environmental (GxE) difference between locations. The Late Syn experiment consisted of 136 entries grown at two organic, one conventional, and one sustainable location. Three of the four locations had yields greater than the highest yielding check, and entries were highly significant within and between locations for yield with a highly significant GxE between locations. The Early Syn experiment consisted of 131 entries grown at one organic, one sustainable, and one conventional location. Two of the locations had significantly higher yields than the checks, and entries were highly significant within and between locations for yield with a highly significant GxE between locations. The E & L Syn experiment consisted of 158 entries at two organic locations. Both locations had entries that were greater in yield than the highest yielding checks, entries were highly significant within and between locations for yield, yet there was no GxE interaction. The BC x BC experiment consisted of 120 entries in one sustainable, two organic, and two conventional locations. Four of the five locations had entries with yield greater than the highest yielding checks, and entries were highly significant within and between locations for yield with a highly significant GxE between locations. In summary, many entries outperformed the checks for yield indicating a difference both within and between conventional and sustainable agricultural systems, with generally significant genotype by environmental interactions between locations. Several genetic backgrounds have been identified for improvement in sustainable agriculture systems.