ARS | Publication request: USING ISSR MARKERS TO QUANTIFY CLONAL VS SEXUAL REPRODUCTION IN FESTUCA IDAHOENSIS (POACEAE)

Submitted to: Botanical Society of America Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: February 28, 1997
Publication Date: N/A

Technical Abstract: Idaho fescue (Festuca idhoensis) is one of the dominant perennial bunch grasses of the Pacific Northwest. It has declined in abundance over the past 100 years, and thus is of interest to a broad range of restoration projects. In order to determine the extent of vegetative reproduction in Idaho fescue, we conducted DNA fingerprinting with inter-simple sequence repeat (ISSR) markers. We sampled 154 plants from two 5 sq. ft. plots at the Eastern Oregon Agricultural Research Center, near Burns, Oregon. The size and postion of each plant was mapped. Three ISSR primers resulted in 18 polymorphic markers which revealed 27 shared genotypes and 67 unique individuals. The presence of ca. 22 discrete clones was inferred from the spatial distribution of shared genotypes. The unique and disjunct genotypes are apparently the result of seed reproduction. All plants in these plots were previously mapped in 1937, therefore we could calculate rates of clonal growth (1.5-2.5 cm per decade). Many clones could be recognized on the basis of morphological criteria, but others were not suspected. Likewise, some apparent clones were composed of genetically distinct individuals. ISSR markers appear to be more robust and more variable than RAPD markers. However, like RAPD markers, they exhibit dominant inheritance. These results demonstrate the value of ISSR markers in documenting the mode of reproduction in plant populations.