Nuclear genome size in Selaginella.
Estimates of nuclear genome size for 9 Selaginella species were obtained using flow cytometry, and measurements for 7 of these species are reported for the first time. Estimates range from 0.086 to 0.112 pg per holoploid genome (84-110 Mb). The data presented here agree with the previously published flow cytometric results for S. moellendorffii. Within the 9 species sampled here, chromosome number varies from 2n = 16 to 2n = 27. Nuclear genome size appears to be strongly correlated with chromosome number (Spearman's rank correlation; p = 0.00003725). Cultivated S. moellendorffii lacks sexual reproduction--manifest by the production of abortive megasporangia. Flow cytometric data generated from a herbarium specimen of a fertile wild-collected S. moellendorffii are virtually indistinguishable from the data generated from fresh material (0.088 vs. 0.089 pg/1C). Therefore, the limited fertility observed in cultivated plants is probably not the result of abnormal chromosome number (e.g., induced by interspecific hybridization).
Little
Damon P
DP
Lewis B. and Dorothy Cullman Program for Molecular Systematic Studies, The New York Botanical Garden, Bronx, NY 10458-5126, USA. dlittle@nybg.org
Moran
Robbin C
RC
Brenner
Eric D
ED
Stevenson
Dennis Wm
DW
D002467:Cell Nucleus / Q000235:genetics*; D018745:Genome, Plant; D032503:Selaginellaceae / Q000235:genetics*