ARS | Publication request: ISOZYME GENETIC MARKERS AND HELIANTHUS GERMPLASM MANAGEMENT

Submitted to: Proceedings Sunflower Research Workshop
Publication Type: Proceedings
Publication Acceptance Date: January 16, 1997
Publication Date: N/A

Technical Abstract: Genetic variation at 20 isozyme loci was surveyed from 146 accessions of wild and domesticated Helianthus annuus L. yielding one of the more extensive data sets of allelic frequencies available for a crop. This isozyme survey provides new insights into the relationships among wild and domesticated sunflowers and the genetic diversity contained within these groups. Standard measures of genetic polymorphism were calculated to assess the efficacy of current germplasm maintenance procedures. A pair-wise interaccession distance matrix constructed from the data set was examined via principal coordinate (PCO) and neighbor-joining (NJ) analyses. Results suggest that the allelic content of domesticated sunflower is a subset of that found in wild populations. In addition, wild sunflowers exhibit geographically-structured variation, as Great Plains accessions seem distinct from southwest U.S./Mexico and California accessions. These results are considered within the context of sunflower germplasm management.