“Phoenix in Flight”: an unique fruit morphology ensures wind dispersal of seeds of the phoenix tree (Firmiana simplex (L.) W. Wight)

Abstract

Background Many seed plants produce winged diaspores that use wind to disperse their seeds. The morphology of these diaspores is directly related to the seed dispersal potential. The majority of winged diaspores have flat wings and only seeds; however, some angiosperms, such as Firmiana produce winged fruit with a different morphology, whose seed dispersal mechanisms are not yet fully understood. In this study, we observed the fruit development of F. simplex and determined the morphological characteristics of mature fruit and their effects on the flight performance of the fruit. Results We found that the pericarp of F. simplex dehisced early and continued to unfold and expand during fruit development until ripening, finally formed a spoon-shaped wing with multiple alternate seeds on each edge. The wing caused mature fruit to spin stably during descent to provide a low terminal velocity, which was correlated with the wing loading and the distribution of seeds on the pericarp. When the curvature distribution of the pericarp surface substantially changed, the aerodynamic characteristics of fruit during descent altered, resulting in the inability of the fruit to spin. Conclusions Our results suggest that the curved shape and alternate seed distribution are necessary for the winged diaspore of F. simplex to stabilize spinning during wind dispersal. These unique morphological characteristics are related to the early cracking of fruits during development, which may be an adaptation for the wind dispersal of seeds.

The origin and dispersal of Firmiana danxiaensis among isolated specific landscapes

“…Firmiana danxiaensis usually flowers from May to June, the most frequent flower visitors were hover fly species (mainly Baccha sp., personal observations), and the seeds are attached to the inner margin of the foliaceous endocarp which can be dispersed by wind with flying wings (Fig. 1), although it may also float in water like a small boat and dispersed by water (Yamada & Suzuki, 1999; Gan et al, 2022).…”

Inflated Ovary May Increase the Dispersal Ability of Three Species in the Cold Deserts of Central Asia

“…Dispersal is a key stage in the life history of plants, and it is an important ecological process that affects the seed fate, spatial distribution and dynamics of plant species, the structure of communities and the establishment of ecosystem function [ 1 , 2 , 3 , 4 ]. The dispersal of diaspores (seeds, fruits, infructescences, and other dispersal units) can be achieved by animals [ 5 ], wind [ 6 ], or water [ 7 ], and plant diaspore traits are directly related to their habitats and dispersal strategies [ 8 , 9 , 10 , 11 , 12 ]. Furthermore, the dispersion-related traits of diaspores affect dispersal patterns [ 13 , 14 , 15 , 16 ], and they may vary in mass and size or have different dispersal appendages [ 17 , 18 , 19 ].…”