Phénologie florale et production fruitière de <i>Syzygium guineense</i> (Willd.) DC. subsp. <i>macrocarpum</i> (Myrtaceae) en zone soudano-guinéenne au Bénin

Les variations phenologiques sont quelquefois considerees comme une strategie d’adaptation ecologique et physiologique des especes a leur environnement. La presente etude a eu pour objectif de determiner les phenophases florales et la production en fruits de Syzygium guineense subsp. macrocarpum sur un echantillonnage de 3 forets naturelles. Les donnees collectees ont porte sur l’identification et la caracterisation des stades de floraison et de fructification, la quantification de la production fruitiere et les caracteristiques dendrometriques des individus. Au total, 85% des arbres et arbustes ont fleuri pendant la saison seche malgre le stress des feux. Ces individus en etat de reproduction ont des diametres compris entre 2,07 et 42,04 cm et des hauteurs allant de 1,50 a 11,50 m. Quatre stades de floraison (fleurs initiees, boutons floraux, fleurs epanouies, fleurs senescentes) et quatre stades de fructification (fruits inities, jeunes fruits, fruits developpes, fruits murs) sont nettement distingues durant 116 a 128 jours. En sommes, la floraison de S. guineense subsp. macrocarpum est abondante (110330 fleurs initiees/ arbre) mais sa production fruitiere est relativement faible (89 a 654 fruits murs/arbre). © 2017 International Formulae Group. All rights reserved. Mots cles: Benin, Syzygium guineense , phenophases, production fruitiere English Abstract  The phenological variations are sometimes considered as a strategy of ecological and physiological adaptation of the species to their environment. The purpose of this study was to determine the floral phenophases and fruit production of S. guineense subsp. macrocarpum on a sampling of 3 natural forests. The data collected focused on the identification and characterization of the flowering and fruiting stages, the quantification of fruit production and the dendrometric characteristics of individuals. A total of 85% of trees and shrubs having bloomed during the dry season despite fire stress. These individuals in the state of reproduction have diameters between 2.07 and 42.04 cm and heights ranging from 1.50 to 11.50 m. Four stages of flowering (floral initiation, developed bud, open flower and senescent flowers) and four stages of fruiting (fruits set, young fruits in development, fruits well developed and mature fruits) are clearly distinguished  during 116 - 128 days. In conclusion, the flowering of S. guineense subsp. macrocarpum is abundant (110330 initiated flowers/ tree) but its fruit production is relatively low (89 a 654 mature fruits /tree). © 2017 International Formulae Group. All rights reserved. Keywords: Benin, Syzygium guineense , phenophases, fruit production