Reproductive Strategy of the Polyploid Species Varronia curassavica Jacq. in Restinga Environment

Abstract

This study aimed to elucidate the breeding strategies of Varronia curassavica, an important medicinal species associated with Brazilian restinga. This was accomplished by combining phenological and genetic data. Every 2 weeks over a period of 2 years, we measured flowering and fruiting phenology to evaluate the activity and intensity of phenophases (n = 60). We evaluated the mating system, pollen ovule ratio and genotypes from progeny and mother plants using 8 nuclear microsatellite loci. We observed flowering and fruiting of V. curassavica at low intensity throughout the entire year, but with 2 distinct peaks, one of which was seasonal, corresponding to the period of gradual increase of temperature and photoperiod. Overlapping of flowering and fruiting strategies favors gene flow among different groups of individuals and between populations by attraction of fauna throughout the year. Analysis of the mating system indicates that V. curassavica is a typical outcrossed species (t^ = 0.98; pollen/ovule ratio = 7087.50). Combining phenology with genetic studies improved our understanding of the reproductive strategies of this species. The typical outcrossing system of V. curassavica reflects the existence of functional self-incompatibility mechanisms still unaffected by changes in genetic balance by polyploidy.

A generalized framework for AMOVA with multiple hierarchies and ploidies

“…The optimal models are: Hoeltgebaum et al . (2017): PES estimate (ΔBIC = −11.516); Julier et al . (2010): CES (ΔBIC = −2.236); Yang et al .…”

“…We also use four empirical autotetraploid genotypic datasets to evaluate the performance of our new AMOVA framework in handling polyploids, and to compare its performance with genodive v3.04 (Meirmans 2020). Hoeltgebaum et al .’s (2017) Varronia curassavica dataset genotyped 681 individuals from 4 populations at 8 loci, Julier et al .’s (2010) Lucerne ( Medicago sativa ) dataset genotyped 463 individuals from 16 populations at 7 loci, Yang et al .’s (2018) Lotus sessilifolius dataset genotyped 48 individuals from 8 populations at 11 loci, and Zwart et al .’s (2016) Grey willow ( Salix cinereal ) dataset genotyped 139 individuals from 4 populations at 7 loci.…”

polygene: Population genetics analyses for autopolyploids based on allelic phenotypes

“… The optimal model evaluated from BIC are: Zwart et al (): PES ( r s = 0.5) (ΔBIC = 1.95); Yang et al (): PES ( r s = 0.25) (ΔBIC = 3.41); Hoeltgebaum et al’s (): CES (ΔBIC = 1.40); Julier et al (): CES (ΔBIC = 2.24). …”