Aquatic botany ELSEVIER Aquatic Botany 56 (1997) 1 - 10 Germination requirements in a population of Typha latifolia Tiziana Lombardi *, Tiziana Fochetti, Andrea Bertacchi, Antonino Onnis Department of Agronomia e Gestione dell'Agro-Ecosistema, Via S. Michele degli $calzi, 2, UniversiChdegli Studi, 56124 Pisa, Italy Accepted 22 October 1996 Abstract The physio-ecological requirements of germination and early achene growth of a population of Typha latifolia L. were studied. The effects of constant (10, 20 and 30°C) or alternating (10/20 °, 20/30 ° and 10/30°C) temperatures, photoperiod (12/12, 8/16, 6/18, 4/20, 2/22 and 0/24 h day/night), after-ripening time and culture medium salinity (NaCI) on germination were assessed. Results showed that germination required light and alternating temperatures (optimal results at 20/30°C with 12/12 h photo-thermoperiod). In these conditions the germination trend showed no appreciable variation during the first year of achene after-ripening. The presence of more than 0.1 M NaC1 in the culture medium caused a significant reduction in the percentage of seeds germinating, and inhibited further seedling growth. Typha latifolia can, therefore, be considered a helio-thermophilic and glycophilic species, at least during early growth stages. © 1997 Elsevier Science B.V. All rights reserved. Keywords: Typhaceae; Seeds; After-ripening; Salinity; Autecology 1. Introduction An important aspect of macrophytes in wetland ecology is the function of these species as bioindicators of the conditions of the water body in which they are at least partially submerged. Such species include Althenia filiformis (Onnis, 1981), Typha * Corresponding author. 0304-3770/97/$17.00 Copyright © 1997 Elsevier Science B.V. All rights reserved. PII S0304-3770(96)01096-0