1a.Objectives (from AD-416):
Characterize progeny of weedy relatives of sorghum and cultivated sorghum containing marker genes, herbicide resistance genes, or quality enhancing genes, for fitness and weediness.
1b.Approach (from AD-416):
This will be a joint effort between ARS, who has genetic materials and expertise to hybridize sorghum with shattercane and/or Johnsongrass, and the University of Nebraska, who has facilities and expertise to evaluate such hybridizations for fitness and weediness. The University of Nebraska will gather data on fitness parameters in the field and greenhouse. Both partners will collaborate in designing the experiments and interpreting the results.
Crosses between shattercane and cultivated sorghum hybrids with non-transgenic herbicide resistance, crosses between Johnsongrass and cultivated sorghum with non-transgenic herbicide resistance, and crosses between Johnsongrass and cultivated sorghum with a transgene coding for a visible marker, have been completed. Progeny from these crosses will be used to study fitness of the resulting hybrids, and gene-flow from sorghum to its weedy relatives. Progeny of shattercane x sorghum crosses were planted in the field during summer of 2012 to evaluate fitness and ecological traits. The information obtained from this research will be critical for deployment decisions and management of new technologies in sorghum.