Abstract
ABSTRACT South Brazilian grasslands are among the most species-rich grasslands worldwide yet they have been suffering ongoing degradation due to land-use. Little is known about the reproductive ecology of the native species of these grasslands. Thus, our goal was to characterize seed traits and germination requirements of three native species of the tribe Tigridieae (Iridaceae, Iridoideae) due to its richness in the Pampa biome and the contrasting morphology, cytogenetics, and geographic distributions of its representatives. We tested if closely related species possess similar seed traits and whether species with wider distributions have broader germination requirements. Seed production and mass were estimated, and morphological analyses, germination experiments and viability tests were performed. Principal component analysis (PCA) was used to describe correlations between seed traits and species’ distributions. Germination was assessed using time-to-event analysis and the Cox model. All seed traits differed among the analyzed species/cytotypes. Final germination percentage (FGP) averaged 39.1 % and with overall viability of 89.9 %. Germination tests showed that seeds benefit from negative photoblasty. Species/cytotypes with wider distributions and heavier and larger seeds generally had better germination performances than narrower distributed species/cytotypes with lighter and smaller seeds.
Highlights
Located in Rio Grande do Sul (RS), the southernmost state of Brazil, the Pampa biome is part of the Río de la Plata ecoregion, the largest continuous grassland in the Americas and whose species-richness within Brazil was estimated at 3,530 species, of which 278 are endemic (Andrade et al 2018)
This study can be considered a pioneering attempt at characterizing seed traits of native grassland species of Iridaceae of the Pampa biome in Rio Grande do Sul
Our results show several differences among the studied species of the genera Kelissa and Herbertia regarding seed traits and ecophysiological requirements
Summary
Located in Rio Grande do Sul (RS), the southernmost state of Brazil, the Pampa biome is part of the Río de la Plata ecoregion (shared with Uruguay and Argentina), the largest continuous grassland in the Americas and whose species-richness within Brazil was estimated at 3,530 species, of which 278 are endemic (Andrade et al 2018). For effective restoration projects to be designed with the aim of conserving the biodiversity and ecosystem services of the Brazilian Pampa, native species that occupy its grassland remnants need to be studied (Overbeck et al 2013; Andrade et al 2015; Havens et al 2015; Andrade et al 2019). There is no consensus about possible patterns of species distributions determined by seed features since patterns are largely species-specific (Paulů et al 2017) Seed traits, such as morphology and ecophysiological requirements for germination, need to be characterized at intra- and interspecific levels to make restoration outcomes more predictable and to employ effective niche regeneration strategies (Barak et al 2018; Saatkamp et al 2018)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
