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Background and aims: Zephyranthes tubispatha is a South American species with ornamental and pharmacological potential. We aimed to study: 1) attributes of fruits, seeds, seed-seedling transition substages, normal and abnormal seedlings; 2) germination due to the effect of different storage periods, seeding times, and exposure to supra-optimal temperatures; and 3) plant vigor. M&M: Samples harvested between 2018 and 2022 (Buenos Aires, Argentina) were used. Fruits and seeds were characterized morphometrically and seminal reserves histochemically. Substages during the seed-seedling transition were defined, and normal and abnormal seedlings were morphologically described. The germination of seeds from different storage periods, seeding times, and thermal conditions was evaluated. Changes in seed viability, electrolyte loss, and plant vigor were studied. Results: In the seeds, lipids and proteins were detected as reserves. Normal and abnormal seedlings and the seed-seedling transition with five substages were described. Seeds of up to 10 months of storage, different seeding times and thermal conditions presented high germination percentages. High temperatures thermoinhibited germination, but did not affect subsequent plant survival. Conclusions: Storage for more than one year showed increased seed mortality and seedling anomalies. The seeding moment conditioned the germination response to the heat treatments, and thermoinhibition did not affect the vigor of the plants produced. [ABSTRACT FROM AUTHOR]

Background and aims: Zephyranthes bifida is a native species of the Pampas ecoregion, with ornamental and medicinal potential. In this work, the seedling was studied for the first time and its seeds were characterized. The objectives were to describe the cotyledon and the first leaf and to provide some anatomical characteristics, as well as to provide information about the embryo/endosperm relationship and the type of reserve substances in the seed. M&M: Seed reserve substances were determined by histochemical tests and the embryo/endosperm surface ratio was obtained with ImageJ. In seedlings, morphological structures were described, using Tillich's terminology (1995; 2007), and some anatomical characteristics. Phenological stages were established for ten days from germination. Results and conclusions: Lipid and protein and lack of starch were determined in embryo and endosperm. In seedlings, the cotyledon is subdivided into a hypophyll and a hyperphyll. Hypophyll presents a ring through which the first eophyll emerges. The distal part of the cotyledonary hyperphyll is completely inserted in the seed, has a haustorial function and has two vascular bundles. Proximal part of cotyledonary hyperphyll has photosynthetic activity and has two vascular bundles too. In the first eophyll, hyperphyll has three vascular bundles. The primary root is attached to the base of the cotyledon through a very short hypocotyl, which in its basal part has rhizoids. Four stages were defined during germination from the emergence of hypophyll, hyperphyll and first eophyll. [ABSTRACT FROM AUTHOR]