Reproductive and vegetative phenophases of Trema micrantha (L.) Blume in the southwest of Paraná state

Abstract

The study aimed to characterize the behavior of the vegetative and reproductive cycles of Trema micrantha (L.) Blume (grandiúva) in a reforestation area in the southwestern region of Paraná state, Brazil. The vegetative and reproductive phenophases of 12 individuals were monitored biweekly, three ones per planting plot. Then, the synchrony of the phenophases, the correlation with the meteorological variables and the periodicity of the events were analyzed. The species showed a high rate of leaf fall in the winter period (June-August), with the resumption of sprouting in September, which was influenced by the increase in the temperature and the volume of rainfall. For the reproductive phenophases, flowering starts in spring (September-October) and reaches its maximum in December; the fruit ripening and the seed dispersal starts in November, focusing on the period from January to April. Flowering and fruiting of the species have an extended annual pattern and high synchrony. The intensity of flower buds, flowers and immature fruits correlates significantly with the temperature and photoperiod variation in the southwest of Paraná state, demonstrating the interaction of Trema micrantha with the environment, as well as its adaptation in subtropical forests of the Atlantic Forest, being the phenology of the conditioned species more strongly by the photoperiod and temperature than by precipitation.

Keywords:
Grandiúva; Phenology; Meteorological variables