Establishment of post-harvest early-developmental categories for viability maintenance of Araucaria angustifolia seeds

• Published in: Acta Botânica Brasílica Vol. 29; no. 4; pp. 524 - 531
• Main Authors: Araldi, Cristhyane Garcia, Coelho, Cileide Maria Medeiros
• Format: Journal Article
• Language: English
• Published: Sociedade Botânica do Brasil 01-12-2015
• Subjects: Brazilian pine; longevity; recalcitrant seeds; seed conservation; seed development
• DOI: 10.1590/0102-33062015abb0061
• EISSN: 0102-3306
• ISSN: 0102-3306; 1677-941X

Araucaria angustifolia seeds are recalcitrant, and their metabolism remains high during storage. This research aimed to describe the initiation of germination in A. angustifolia seeds during storage in order to standardize the assessment of physiological quality and to promote seed conservation. Seeds were collected from two populations and stored for 270 days in the natural laboratory environment and cold chamber. Seeds were classified according to four early developmental stages: I - mature seeds; II - seeds with elongation along the embryonic axis; III - beginning of root protrusion; IV - advanced germination stage, with seedling shoots. After categorization, physical and physiological quality was assessed. In freshly collected seeds, only category I was observed. At 270 days, approximately 40% of seeds were in category III in laboratory conditions, while the maintenance in a cold chamber delayed germinative metabolism. Viability tests showed that seeds in categories III and IV were more susceptible to damage caused by storage. In conclusion, the percentage of viable A. angustifolia seeds depends on the development stage after collection. Seeds that have reached early developmental category III should be prioritized for propagation, while those remaining in categories I and II should be longer stored with periodic assessment for reduction in physiological quality.