What affects the desiccation tolerance threshold of Brazilian Eugenia (Myrtaceae) seeds?

• Published in: Journal of plant research Vol. 135; no. 4; pp. 579 - 591
• Main Authors: de Almeida Garcia Rodrigues, Guilherme, da Silva, Danielle, Ribeiro, Maiara Iadwizak, Loaiza-Loaiza, Oscar Alfonso, Alcantara, Suzana, Komatsu, Roberto Akitoshi, Barbedo, Claudio Jose, Steiner, Neusa
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.07.2022; Springer Nature B.V
• Subjects: Abiotic factors; Biomedical and Life Sciences; Correlation; Desiccation; drought tolerance; Eugenia uniflora; Germination; Life Sciences; Plant Biochemistry; Plant Ecology; Plant Physiology; Plant populations; Plant Sciences; rain; Rainfall; Regular Paper – Ecology/Ecophysiology/Environmental Biology; seed collecting; Seed collection; Seed germination; seedling growth; Seedlings; Seeds; Species; temperature; viability; vigor; Wildlife conservation; Climate change; Provenance; Recalcitrant; Wild species; Germination; Seed conservation
• DOI: 10.1007/s10265-022-01396-7
• ISSN: 0918-9440; 1618-0860

Desiccation sensitive (DS) seeds are shed at high water contents (WC) and metabolically active, but WC thresholds vary broadly among species even in the same genus. Eugenia is an important ecological genus that has high occurrence in several Brazilian morphoclimatic domains. In this study, we assessed seed desiccation tolerance of five Eugenia species collected in specific meteorological conditions. We reported the species geographical ranges and verified the rainfall and temperature of species sites in the year prior to seed collection. We also assessed initial WC, seed germination and vigor and seedling growth upon desiccation. Eugenia uniflora was the widest spread among the five species, while E. astringens was the most restricted. In this specific study, widespread species showed a higher WC threshold than restricted species. In the same way, the WC of fresh seeds was not correlated to the desiccation tolerance threshold. Seed desiccation tolerance was species dependent and correlated with the environmental status of seed collection sites. Wetter and warmer conditions were correlated to the E. uniflora higher DS threshold. Low rainfall and temperature corresponded to a lower desiccation sensitivity of E. astringens seeds. Seeds of the five species lost half viability between 0.44 and 0.25 g H 2 O g DW − 1 and after 65–270 h of desiccation. Our results indicate that abiotic factors impact plant populations during the seed production season and can drive seed desiccation tolerance threshold and physiological behavior. These results should be taken into account in ex-situ plant conservation programs and tropical species management.