Understanding desiccation tolerance and sex-specific responses in Bryum argenteum: insights from phenological phases and physiological analyses

Author(s)

dos Santos, Wagner Luiz ; Medina-Ramos, Andrea ; Greenwood, Joshua ; Porto, Katia Cavalcanti ; Pinheiro, Fabio ; Stark, Lloyd R.

• Document type: Journal article
• Source: ANNALS OF BOTANY; v. 134, n. 2, p. 14-pg., 2024-05-04.

Abstract

Background and Aims Desiccation tolerance (DT) is crucial for survival in arid environments, where organisms develop strategies in reproduction, maintenance and defence to cope with water scarcity. Therefore, investigating the relationship between reproduction and DT is essential to understand the ecology and adaptive strategies of species. This study explores the connection between the development of male and female gametangia in the moss Bryum argenteum and the decrease in DT during the progression of phenological phases in gametangia and protonema.Methods Samples collected from a dry tropical forest in Brazil were cultivated, cloned and subjected to desiccation. Subsequently, the physiological parameters of shoots and protonemata were analysed. Shoot and protonema regeneration were monitored for 28 d after the physiological analyses. Both phases were subjected to control and desiccation treatments.Key Results Significant effects of desiccation and sex on the physiological parameters and regeneration capacity of shoots and protonemata were found. Male shoots generally exhibited lower values of Fv/Fm (quantum efficiency of photosystem II) and phi PSII (effective quantum yield of photosystem II), while females demonstrated higher values and better recovery after desiccation. Protonemata also showed variation in Fv/Fm over time and with sex, with no significant differences in phi PSII between them. Desiccated male shoots had higher mortality rates and produced fewer new shoots. For females, the regeneration patterns varied between the desiccation-exposed groups and the control, with decreased shoot production, and some protonemata growing into filaments without forming shoots.Conclusion These findings improve our understanding of the ecological responses of bryophytes to desiccation stress and provide insights into their adaptive strategies in challenging environments, such as the possible rarity of males in dioicous moss populations. (AU)

• FAPESP's process: 20/02150-3 - Life at the edge: how environmental gradients affect an orchid species distributed along the coastal vegetation?
• Grantee: Fábio Pinheiro
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/10639-5 - Center for Research on Biodiversity Dynamics and Climate Change
• Grantee: Leonor Patricia Cerdeira Morellato
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 21/09506-0 - Desiccation tolerance in bryophytes: costs and benefits related to moss reproduction
• Grantee: Wagner Luiz dos Santos
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 18/24397-0 - How does sexual systems relates to reproductive traits, genetic diversity and thermotolerance in Fissidens Hedw. (Fissidentaceae, bryopsida)?
• Grantee: Wagner Luiz dos Santos
• Support Opportunities: Scholarships in Brazil - Doctorate