Prospecting elite donor plants and characterization of endogenous hormonal status in seeds of Brazilian chestnuts (Lecythidaceae)

The Brazilian rainforests host the species Lecythis pisonis and Lecythis lanceolata , potential producers of functional nuts. This study aimed to: (1) demarcate and characterize phenotypically and genotypically both species; (2) analyze seed biometric and physiological traits; (3) investigate seed hormonal composition and its influence on germination; and (4) assess early seedling phenotypes. L. pisonis showed higher genetic diversity than L. lanceolata . Seedling emergence was highest in seeds from specific trees: 1 and 2 ( L. pisonis ) and 1, 2, 4, 5, and 6 ( L. lanceolata ). Abscisic acid (ABA) and 1-aminocyclopropane-1-carboxylic acid (ACC) were negatively correlated with seed growth in both species. In L. pisonis , methyl jasmonate (MeJA) in the endosperm correlated positively with seedling emergence, while MeJA in the tegument negatively affected shoot formation in both species. In L. lanceolata , ABA in the seed coat positively influenced mean emergence time, suggesting a dormancy mechanism. These findings enhance the understanding of seed physiology and early development in L. pisonis and L. lanceolata , offering key insights for future propagation and commercial cultivation efforts.