Factors influencing reproductive success in the clonal moss, Hylocomium splendens
Författare
Summary, in English
Female reproductive success in the unisexual
perennial clonal moss Hylocomium splendens was
examined by recording, if the segment was reproductive
[produced sporophyte(s)] or not, together with several
distance-to-male and male density variables, and segment
size. This was done for every female segment in a
population over a 5 year study period. A high fraction
of the population could be sexed because we monitored
the population in situ for 5 years, and thereafter harvested
the population for electrophoretic analysis from
which the clonal identity and expressed sex could be
deduced. Fertilization distances in H. splendens were
short, indicated by the fact that as many as 85% of the
female segments with sporophytes were situated within a
distance of 5.0 cm from the nearest male. The longest
distance measured between a sporophytic female and the
closest male was 11.6 cm. However, analysed within a
generalized linear modelling (GLM) framework, the
year was the best single predictor for the presence of H.
splendens sporophyte although female-segment size and
distance to the closest situated male were also strongly
significant. The two latter factors explained larger fractions
of variation in sporophyte presence in a GLM
model with three predictors than in single-predictor
models. This is because (i) the large variation in sporophyte
production among years partly obscures the
strong general increase in sporophyte production with
increasing female-segment size and vitality, and (ii) the
between-year variation and the size obscure the effect of
the distance to the most proximate male. To our
knowledge, this study is the first to incorporate into one
model the relative importance of several factors for
bryophyte reproductive success. Our results demonstrate
the value of multiple-predictor approaches in studies of
reproductive success.
perennial clonal moss Hylocomium splendens was
examined by recording, if the segment was reproductive
[produced sporophyte(s)] or not, together with several
distance-to-male and male density variables, and segment
size. This was done for every female segment in a
population over a 5 year study period. A high fraction
of the population could be sexed because we monitored
the population in situ for 5 years, and thereafter harvested
the population for electrophoretic analysis from
which the clonal identity and expressed sex could be
deduced. Fertilization distances in H. splendens were
short, indicated by the fact that as many as 85% of the
female segments with sporophytes were situated within a
distance of 5.0 cm from the nearest male. The longest
distance measured between a sporophytic female and the
closest male was 11.6 cm. However, analysed within a
generalized linear modelling (GLM) framework, the
year was the best single predictor for the presence of H.
splendens sporophyte although female-segment size and
distance to the closest situated male were also strongly
significant. The two latter factors explained larger fractions
of variation in sporophyte presence in a GLM
model with three predictors than in single-predictor
models. This is because (i) the large variation in sporophyte
production among years partly obscures the
strong general increase in sporophyte production with
increasing female-segment size and vitality, and (ii) the
between-year variation and the size obscure the effect of
the distance to the most proximate male. To our
knowledge, this study is the first to incorporate into one
model the relative importance of several factors for
bryophyte reproductive success. Our results demonstrate
the value of multiple-predictor approaches in studies of
reproductive success.
Avdelning/ar
Publiceringsår
2006
Språk
Engelska
Sidor
445-454
Publikation/Tidskrift/Serie
Oecologia
Volym
147
Issue
3
Dokumenttyp
Artikel i tidskrift
Förlag
Springer
Ämne
- Ecology
Status
Published
ISBN/ISSN/Övrigt
- ISSN: 1432-1939