Location: Plant Introduction Research
2018 Annual Report
Accomplishments
1. Evaluation of top Germplasm Enhancement of Maize (GEM) released lines. Performance of GEM released lines across a wide range of commercial elite testers would provide information on the value of the lines in breeding programs. The GEM Programs at Ames and Raleigh identified the top 48 lines and distributed seed to each of the five private industry members of the Technical Steering Group (TSG). The 48 lines were crossed to elite testers from each company and the resulting hybrids were tested within each companies system in 2017. The participants also agreed to test these hybrids again in 2018. Data from the 2017 trials was returned to ARS researchers at Ames, Iowa, and run through a general combining ability (GCA) and specific combining ability (SCA) analysis which provides a competitive evaluation of the yield trial performance and potential breeding value of the top GEM lines. This is the first time that lines released from the GEM program have been evaluated for yield potential with current elite commercial germplasm across a wide range of environments. The data will be helpful to all GEM stakeholders.
2. Resistance to Bacterial Leaf Streak. Bacterial Leaf Streak was first confirmed in Nebraska corn fields in 2016 and in Brazilian maize production fields in 2018. Since then, significant yield losses have been confirmed in various locations. The full potential yield impact of the disease in the U.S. is not yet understood and little is known regarding sources of genetic resistance. Collaboration with plant pathologists at the University of Nebraska to screen 100 GEM released lines for disease resistance identified multiple lines with resistance, which has not been found previously. The test is being repeated for confirmation in 2018, and lines can be incorporated into breeding programs specifically for this disease.
