Abstract Detail

Recent Topics Posters

Klips, Robert [1].

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

Physcomitrium pyriforme (Funariaceae) is a spring ephemeral moss that is common in agricultural fields. Its sexual condition is cladoautoicous, with male inflorescences (perigonia) occurring at the tips of short basal or lateral branches, and female ones (perichaetia) at the stem apices. Owing to the close proximity of the sex organs on each stem, as well as those on co-occurring stems in a clump that may be genetically identical, there is the potential for intra-gametophytic self-fertilization to occur, resulting in sporophytes that are homozygous at all genetic loci. Nevertheless, micro-environmental conditions associated with heavy rains during sex organ maturation in autumn could effect long-distance sperm transport, resulting in outcrossed sporophytes. To ascertain the mating patterns of this moss, thirty-five sporophytes were gathered from widely separated locations in a wet meadow in central Ohio and genotyped at 8 variable microsatellite loci having Polymorphism Information Content (PIC) values ranging from 0.19 to 0.78, and expected heterozygosities ranging from 0.30 to 0.83. Twenty-seven individuals (77.1%) were homozygous at all 8 loci, strongly indicative of self-fertilization. An additional 7 individuals (20%) all shared an allele for which they were all homozygous and which was absent from the other members of the population. These 7 sporophytes were also heterozygous at 3 or more of the 8 loci (average 5.3 heterozygous loci), and in generally greater than expected frequencies, strongly suggestive of a polyploid cytotype that is also not inconsistent with the predominantly selfing mating pattern exhibited by the 27 others. Only one individual (3%) appeared to be an outcrossed sporophyte, as it carried alleles all of which were found among the evidently selfing plants, while also being heterozygous at 3 loci. These results elucidate the overall mating pattern as very predominantly selfing, but don’t reveal whether it was accomplished by mating among stems, within stems, or between the progeny of genetically identical spores. DNA microsatellites could be applied to a more fine-grained analysis of the genetic architecture of Physcomitrium moss clumps both in situ and under controlled conditions to ascertain further details of the reproductive ecology of this very successful, widespread, and variable bryophyte.

Broader Impacts:

1 - The Ohio State University, Evolution, Ecology, and Organismal Biology, 1465 Mt. Vernon Ave., Marion , OH, 43302, USA

Keywords:
bryophyte
Physcomitrium
microsatellite
mating system.

Presentation Type: Recent Topics Poster
Session: P
Location: Grand Salon A - D/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 5:30 PM
Number: PRT039
Abstract ID:1335
Candidate for Awards:None