Title

Clonal population structure and genetic variation in sand-shinnery oak,Quercus havardii (Fagaceae)

Document Type

Journal article

Source Publication

American Journal of Botany

Publication Date

1998

Volume

85

Issue

11

First Page

1609

Last Page

1617

Publisher

Botanical Society of America, Inc.

Keywords

Allozyme, clone, Fagaceae, genetic variation, isozyme, population structure, Quercus

Abstract

We investigated clonal population structure and genetic variation in Quercus havardii (sand-shinnery oak), a deciduous rhizomatous shrub that dominates vegetation by forming uninterrupted expanses of ground cover over sandy deposits on the plains of western Texas, western Oklahoma, and eastern New Mexico. Isozyme electrophoresis (15 loci coding 11 enzymes) was used to recognize and map clones arrayed in a 2000-m transect (50-m sample intervals) and a 200 × 190 m grid (10-m sample intervals). Ninety-four clones were discovered, 38 in the transect and 56 in the grid, resulting in an estimated density of ∼15 clones per hectare. Clones varied greatly in size (∼100–7000 m2), shape, and degree of fragmentation. The larger clones possessed massive interiors free of intergrowth by other clones, while the smaller clones varied in degree of intergrowth. The population maintained substantial levels of genetic variation (P = 60%, A = 2.5, Hexp = 0.289) comparable to values obtained for other Quercus spp. and for other long-lived perennials. The population was outcrossing as evidenced by conformance of most loci to Hardy-Weinberg expected genotype proportions, although exceptions indicated a limited degree of population substructuring. These data indicate that despite apparent reproduction primarily through vegetative means, Q. havardii possesses conventional attributes of a sexual population.

Print ISSN

00029122

E-ISSN

15372197

Publisher Statement

Copyright © 1998 Botanical Society of America, Inc. Access to external full text or publisher's version may require subscription.

Full-text Version

Publisher’s Version

Recommended Citation

Mayes, S. G., McGinley, M. A., & Werth, C. R. (1998). Clonal population structure and genetic variation in sand-shinnery oak,Quercus havardii (Fagaceae). American Journal of Botany, 85(11), 1609-1617. Retrieved from http://www.amjbot.org/content/85/11/1609