Oxidative Stress and ABA Dynamics Modulate Dormancy and Longevity of Stored Caryocar brasiliense (Caryocaraceae) Seeds

• Published in: Journal of plant growth regulation Vol. 44; no. 6; pp. 3012 - 3024
• Main Authors: Pinto, Valéria de Oliveira, Ribeiro, Leonardo Monteiro, Martins, Cristina de Paula Santos, Mota, Mauro Franco Castro, Dias, Daiane Souza, Patez, Fabio Henrique, Lopes, Paulo Sergio Nascimento
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.06.2025; Springer Nature B.V
• Subjects: Abscisic acid; Accumulation; Agriculture; Biomedical and Life Sciences; Caryocar brasiliense; Dormancy; Dynamics; Embryos; Fruit trees; Germination; Humidity; Hydrogen peroxide; Life Sciences; Longevity; Moisture content; Mortality; Oxidative stress; Physiology; Plant Anatomy/Development; Plant Physiology; Plant Sciences; Pyrenes; Room temperature; Seeds; Synthesis; Temperature; Water; Water content; Antioxidant system; Lipid peroxidation; Seed storage; ABA gene expression; Germination
• ISSN: 0721-7595; 1435-8107
• DOI: 10.1007/s00344-024-11592-5

The interactions between oxidative stress and ABA dynamics constitute the main mechanisms controlling seed longevity and germination. However, little is known, about this subject in terms of tropical species. We evaluated the relationships between oxidative stress and ABA dynamics, and the dormancy and longevity of Caryocar brasiliense seeds, a fruit tree endemic to the Brazilian Cerrado. Freshly dispersed pyrenes (endocarp-enveloped seeds) were stored at room temperature and monitored for one year for germination, mortality, oxidative stress (H 2 O 2 and MDA concentrations, and SOD, APX, and CAT activities), and ABA dynamics (ABA1, NCED4, NCED9 expression and hormone quantification). Newly dispersed seeds have high water contents, pronounced dormancy (related to the synthesis and accumulation of ABA), and tolerance to deterioration (low levels of oxidative stress). Seed water content becomes reduced and oxidative stress increases after between 40 and 60 days of storage, which lead to reductions in ABA synthesis and accumulation and the relief of dormancy. After this period, limitations of the control of oxidative stress lead to gradual reductions of the synthesis and accumulation of ABA, resulting in seed mortality. Interactions between oxidative stress control and ABA dynamics in C. brasiliense seeds during the second and third months of storage result in optimal seed quality, characterized by high germination rates.