Does inbreeding avoidance maintain gender dimorphism in Wurmbea dioica (Colchicaceae)?


The maintenance of females in gender dimorphic populations requires that they have a fitness advantage to compensate for their loss of male reproductive function. We assess whether inbreeding avoidance provides this advantage in two subdioecious Wurmbea dioica populations by estimating seed production, outcrossing rates and inbreeding depression. Fruiting males produced less than half as many seeds as females, owing to low outcrossing rates and early acting inbreeding depression. Inbreeding coefficients of fruiting males demonstrated that progeny were more inbred than their parents, implying that few selfed progeny reach maturity, as confirmed by inbreeding depression estimates that exceeded 0.85. In a glasshouse experiment, open-pollinated females exhibited a fitness advantage of 3.7 relative to fruiting males, but when we increased fruiting male outcrossing rate, female advantage was only 1.4. This reduced advantage is insufficient to maintain females if nuclear genes control sex. Thus, inbreeding avoidance could maintain females at high frequencies, although this is contingent upon high frequencies of fruiting males, which can be altered by environmentally determined gender plasticity

Similar works

Full text


The Australian National University

Full text is not available
oai:openresearch-repository.anu.edu.au:1885/92147Last time updated on 4/26/2018

This paper was published in The Australian National University.

Having an issue?

Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.