Abstract Detail

Recent Topics Posters

Blake, Jennifer [1], Struwe, Lena [2].

Temporal and environmental dimensions of variable sex expression in striped maple, Acer pensylvanicum (Sapindaceae).

Gender in plants is usually a fixed trait: while the environment may modulate sex allocation in some species, the individual’s sex remains constant.  However in rare cases, a plant may change gender during its lifetime. The change from one primary gender phase to another phase, diphasy, is most commonly attributed to developmental changes in size.  A better understanding of the mechanisms influencing gender plasticity is important to our understanding of theory regarding sex allocation and the evolution of dioecy.
Using striped maple (Acer pensylvanicum; Sapindaceae) as a study system, I investigated the distribution of genders and gender change in this sexually plastic species. I recorded the gender of 248 individuals divided amongst five wild populations in New Jersey, in 2014 and 2015. The most common pattern was to express the same gender in both years; 75% of all trees did not change sex. While 85% of all males remained male in the second year, only 40% of ambisexual trees remained ambisexual. Among trees changing gender phases, the most common transitions were from male to ambisexual (31%) and male to female (16%).  Non-reproductive trees that became reproductive in the second year changed exclusively to male.  Of trees dying of natural causes, 70% were female before dying.
The mechanisms causing changes in sex expression in striped maple are poorly understood.  Preliminary data suggest that both size and injury may impact the frequency and direction of gender change.  Pilot forced flowering studies indicate that the final sex of a flower is determined within one month of flowering.  This shows that striped maple may remain receptive to environmental sex-determining cues through early spring.    

1 - Rutgers University, Ecology and Evolution , 237 Foran Hall, 59 Dudley Rd, Cook Campus , New Brunswick, New Jersey, 08901, USA
2 - Rutgers University, Dept of Ecology, Evolution, & Natural Resources, 237 Foran Hall, 59 Dudley Road, New Brunswick, NJ, 08901, USA

Keywords:
sexual reproduction
gender plasticity
Acer
sex expression.

Presentation Type: Recent Topics Poster
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PRT058
Abstract ID:1844
Candidate for Awards:None