Differential effects of floral display on female and male reproductive success in the hermaphroditic herb Primula farinosa

• A prominent floral display increases attractiveness to pollinators, but may be associated with a cost in terms of increased risk of damage from antagonists.  If damage to reproductive parts by grazers and seed predators mostly occurs after pollen dispersal, a large floral display may benefit both female and male reproductive functions, while costs may predominantly be expressed through female function. The hermaphroditic herb Primula farinosa is dimorphic for floral display with a long-scaped morph, which displays its flowers well above the ground, and a short-scaped morph, which displays its flowers close to the ground. We conducted a field experiment with genotyped plants at two sites to examine whether scape morph differentially affects female and male reproductive success and whether the two scape morphs mate assortatively. Female reproductive success was assessed by quantifying seed production and male siring success by genotyping offspring. The intensity of seed predation differed between experimental sites (59% vs. 9% of fruits attacked), whereas differences in grazing damage were smaller and not statistically significant (9% vs. 6%). At the site where seed predation was high, the long-scaped morph produced significantly fewer seeds, but sired more offspring than did the short-scaped morph. At the other site, the two morphs did not differ significantly in seed production or siring success. The scape morphs did not mate assortatively. The results indicate that interactions with pollinators and antagonists can differentially affect selection on floral display through male and female function and could potentially lead to a relationship between floral display and plant functional gender. They further demonstrate that a full understanding of selection on floral traits requires that selection through both male and female reproductive success is considered.

Ämnesord

NATURVETENSKAP  -- Biologi -- Ekologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Ecology (hsv//eng)

NATURVETENSKAP  -- Biologi -- Evolutionsbiologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences -- Evolutionary Biology (hsv//eng)

Nyckelord

Assortative mating

Biotic interactions

Functional gender

Paternity analyses

Siring success

Publikations- och innehållstyp

vet (ämneskategori)

ovr (ämneskategori)