XVI International Botanical Congess

In T. underwoodii, a sessile-flowered species, there was an expected positive correlation between leaf area and length (Pearson correlation coefficient, R2=0.93) and only the largest individuals flowered (mean leaf area =104 mm2). Within flowering individuals, leaf length was only moderately correlated with sepal length (R2=0.69), petal length (R2=0.56) and ovule number (R2=0.58), but leaf length was strongly correlated with ovary size (length at bud opening, R2=0.84). Surprisingly, ovary size was only weakly correlated with ovule number (R2=0.39). These allometric relationships suggest that plant size strongly determined the likelihood of flowering but only moderately influenced flower size, and perhaps attractiveness to pollinators. However, larger plants may provide more structural protection (via a larger ovary) to developing seeds.