Germinação de sementes de Talinum fruticosum (L.) Juss. (Talinaceae) sob diferentes condições de luminosidade e gradiente de umedecimento do substrato

Abstract

Talinum fruticosum is a plant with high nutritional value and is propagated by seeds. The aim of this study was to evaluate the germination of three batches of T. fruticosum seeds under different light and substrate moistening conditions. The seeds were collected at different times and stored until the experiment was carried out. In the first experiment, germination was assessed under different light conditions: 12/12h photoperiod, no photoperiod (only flashes of light) and total darkness. The second experiment was the emergence of the seedlings in sand substrate irrigated with different levels of water (1mm of water, 100%, 80% and 60% of the substrate's water retention capacity), at the end of the experiment the percentage and the Emergence Speed Index (ESI) and the survival rate of the seedlings were evaluated. The highest germination percentage was obtained in an environment with a 12/12h photoperiod and the lowest in total darkness. Seed lots with shorter storage times tended to be more vigorous. The seeds showed a higher percentage of seedling emergence in sand when subjected to greater water availability and water deficit. The highest speed of emergence occurred in the batch with the shortest storage time, and the highest seedling survival rate was obtained in the treatment with 60% water retention capacity.