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 (non-herbicide resistant) were completed to produce F1 hybrids and F2 populations to study the fitness characteristics of the progeny in these generations. Crosses between shattercane and an herbicide resistant sorghum inbred line were completed, and the fitness characteristics of progeny were evaluated in the field with the herbicide present or absent. These experiments will be developed into a model that simulates pollen flow and the population dynamics for sorghum and its weedy relatives over the next year. The information obtained from this research will be critical for deployment decisions and management of new herbicide-resistance and transgenic technologies in sorghum.