Maternal Environmental Light Conditions Affect the Morphological Allometry and Dispersal Potential of Acer palmatum Samaras

Bin J W Chen,Xia Xu,Xinyu Wang,Heinjo J During,Yuting Dong,Niels P R Anten

doi:10.3390/f12101313

Abstract

Seed dispersal plays critical roles in determining species survival and community structures. Since the dispersal is biologically under maternal control, it is hypothesized that intraspecific variation of dispersal potential and associated traits of seeds (diaspores) should be influenced by maternal habitat quality. We tested this hypothesis by examining the effects of maternal environmental light condition on morphological traits and descending performance of nearly 1800 wind-dispersed samaras collected from maple species Acer palmatum. Results showed that samaras produced by trees from shaded microhabitats had greater dispersal potential, in terms of slower terminal velocity of descent, than those produced in open microhabitats. This advantage was largely attributed to morphological plasticity. On average, samaras produced in shaded microhabitats, as compared to those produced in open habitats, had lower wing loading by only reducing weight but not area. In allometric details, in the large size range, samaras from shaded microhabitats had larger areas than those from open microhabitats; in the small size range, samaras from shaded microhabitats had wider wings. These findings suggest that greater dispersal potential of samaras in response to stressful maternal light environment reflected an active maternal control through the morphological allometry of samaras.

Highlights

Dispersal, a phenomenon that depicts an individual unidirectionally moving away from its mother or place of birth, is ubiquitous in all organisms [1], and has long been the interests of ecologists [2,3]
Ample evidence shows a large variation in seed dispersal within species [14]. Such a variation is believed to have important ecological and evolutionary consequences, our understanding of its drivers is still limited [5,15]. While much of this intraspecific variation in seed dispersal traits is believed to be due to intrinsic genetic factors, some studies hypothesized that the growth environments of parental plants, maternal plants in particular, have a great contribution [16,17], the phenomenon of which is often coined as a maternal environmental effect
Samaras produced by A. palmatum trees which grew in shaded microhabitats had a significantly slower terminal velocity and less weight than those produced by trees which grew in condition had open microhabitats

Summary

Introduction

A phenomenon that depicts an individual unidirectionally moving away from its mother or place of birth, is ubiquitous in all organisms [1], and has long been the interests of ecologists [2,3]. Ample evidence shows a large variation in seed dispersal within species [14] Such a variation is believed to have important ecological and evolutionary consequences, our understanding of its drivers is still limited [5,15]. While much of this intraspecific variation in seed dispersal traits is believed to be due to intrinsic genetic factors, some studies hypothesized that the growth environments of parental plants, maternal plants in particular, have a great contribution [16,17], the phenomenon of which is often coined as a maternal environmental effect (reviewed by Donohue [18]). Seeds should be dispersed to suitable sites for better growth and reproduction in order to increase the fitness of both offspring and maternal plants. To date, direct evidence of maternal environmental effects, especially from fields, on seed dispersal potential is still limited [10,12]

Methods

Results

Discussion

Conclusion