Present address: Professor Emeritus of Kyoto University, 303-204 Greentown Makishima, 51-1 Motoyashiki, Makishima-cho, Uji, Kyoto 611-0041, Japan.
Demographic genetics of American beech (Fagus grandifolia Ehrh.) IV. Development of genetic variability and gene flow during succession in a coastal plain forest in Maryland
Article first published online: 6 NOV 2008
© 2008 The Authors. Journal compilation © 2008 The Society for the Study of Species Biology
Plant Species Biology
Volume 23, Issue 3, pages 159–173, December 2008
How to Cite
KITAMURA, K., TAKASU, H., HAGIWARA, S., HOMMA, K., O'NEILL, J., WHIGHAM, D. F. and KAWANO, S. (2008), Demographic genetics of American beech (Fagus grandifolia Ehrh.) IV. Development of genetic variability and gene flow during succession in a coastal plain forest in Maryland. Plant Species Biology, 23: 159–173. doi: 10.1111/j.1442-1984.2008.00228.x
- Issue published online: 6 NOV 2008
- Article first published online: 6 NOV 2008
- Received 19 February 2008; accepted 14 September 2008
- conservation biology;
- Fagus grandifolia;
- gene flow;
- spatial autocorrelation
Genetic recovery of an American beech (Fagus grandifolia) population in deciduous forests that were once pastures was studied using 16 allozyme loci from 410 individuals in a 600 m × 600 m study plot in Maryland, USA. We also examined the spatio-temporal genetic structure of the American beech population at a regional scale. Overall genetic diversity of mature trees was measured by estimating average heterozygosity (H = 0.156). Rare alleles were observed in five loci, Lap, 6Pdgh3, Pgi, Adh1 and Got3. Mature individuals were divided into three size classes based on d.b.h. The genetic component of each size class was compared and it was revealed that several alleles (Pgm-a, 6Pgdh3-a and Lap-b) were shared only in specific size classes. The spatial distribution of the genotypes demonstrated a conspicuous localization in three loci (Aco, Adh1 and Idh). Spatial autocorrelation analyses were carried out among the mature trees for a 20 m interval, and were positive for 0–120 m and negative for >180 m. Distrograms indicated that a unique genetic localization occurs among mature individuals. Seven hundred and seventy-five seedlings in the 10 m × 120 m transect were analyzed to measure gene flow via seed and/or pollen. We obtained a genetic neighborhood area of 1.17 ha and an effective population size of 32.4. The temporal and spatial modes of genetic recovery of the population are discussed in the context of conservation biology.