Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/18/1999
Publication Date: N/A
Citation: Interpretive Summary: The rapid loss of native pecan populations, generally to agriculture, potentially threatens the genetic diversity of pecan as a horticultural crop. Estimates were made of the amount of outcrossing taking place in several native pecan populations so as to assess whether the decline in native pecan trees has had any impact on how pecan has partitioned its genetic diversity within and among wild populations. It was found that wild populations of pecan still exhibit normal rates of outcrossing, thus inbreeding and subsequent loss of genetic diversity does not appear to be a problem in wild pecan populations. This means that wild populations of trees are likely to continue to exhibit in their posterity a considerable amount of genetic diversity, thus ensuring the availability of genes for future cultivar development efforts.
Technical Abstract: Estimates of single and multilocus outcrossing rates as well as relatedness among progeny of individual seed trees were obtained for 14 populations of pecan. Mean outcrossing estimates were not significantly different from 1.0 and relatedness values indicate that most progeny within families are half sibs. Biparental inbreeding was insignificant in all study sites, and inbreeding coefficients indicated that populations were close in inbreeding equilibrium.