Abstract Detail

Bryological and Lichenological Section/ABLS

Klips, Robert A. [1].

DNA microsatellite analysis of sporophytes of the short-lived arable moss Physcomitrium pyriforme reveals a predominantly self-fertilizing mating pattern.

Physcomitrium pyriforme (Funariaceae) is a monoecious moss with the potential for producing sporophytes either via outcrossing or intra-gametophytic self-fertilization. A core set of microsatellite markers was identified for use in population genetic studies of this species, and employed to ascertain its mating patterns. An initial collection of 88 sporophytes gathered from widely separated locations in a meadow in central Ohio, USA was screened for genetic uniformity based on trnL-F DNA sequences, and found to display considerable heterogeneity. Fifty-three members of the largest clearly defined clade were selected for genotyping at 6 variable microsatellite loci having expected heterozygosities ranging from 0.11 to 0.70. Fifty-two individuals (98.2%) were homozygous at all 6 loci, strongly indicative of self-fertilization. Only one individual (1.8%) appeared to be an outcrossed sporophyte, being heterozygous at 4 loci. Twenty-three samples that constituted a second well-marked clade displayed complex microsatellite genotypes strongly suggestive of a polyploid cytotype that, although not readily amenable to further analysis, is also not inconsistent with the predominantly selfing mating pattern exhibited by the 53 others. Male and female branches within gametophyte stems were observed to develop simultaneously or nearly so, and, in 4 dense moss clusters within which samples of 8 gametophytes were genotyped, all 8 were found to be identical within each cluster. These results elucidate the overall mating pattern as being very predominantly selfing, and suggest that the species reproduces principally in what is, in effect, a clonal fashion, via the union of genetically identical gametes. This could be occurring both within and between gametophytes.

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Keywords:
Physcomitrium
moss
mating system.

Presentation Type: Oral Paper:Papers for Sections
Session: 16
Location: Salon 11/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 3:00 PM
Number: 16007
Abstract ID:881
Candidate for Awards:None