Estudo fenológico do Handroanthus impetiginosus (Mart. ex DC.) Mattos em área urbana de Dom Expedito Lopes

Abstract

Phenology is the science that studies biological events that occur repeatedly during the development of a species, population, or community, following a specific periodic rhythm such as flowering and fruit maturation, which depend on biotic and abiotic factors. Understanding the phenological aspects of a plant becomes an important tool for comprehending the factors that influence the survival and reproduction of the plant. This study aims to investigate the phenological patterns of the purple ipê Handroanthus impetiginosus (Mart. ex DC.) Mattos in the urban area of the municipality of Dom Expedito Lopes – PI, seeking to understand the influence of environmental and seasonal factors on its reproductive cycle. Between June 2024 and May 2025, ten adult individuals of the species located along the city's main avenue were monitored through biweekly visits, recording four phenophases: floral bud, open flower, green fruit, and ripe fruit. The method proposed by Fournier (1974) was used to estimate the intensity of phenophases, and the Rayleigh test was applied to analyze the seasonal distribution of the events. The results revealed a well-defined pattern for the reproductive phenophases, concentrated in the driest and hottest months of the year, particularly between July and September, with a flowering peak in August. It was also observed that factors such as precipitation and temperature directly influenced the intensity and synchrony of phenological events. The species exhibited a type 1 pattern, characterized by synchronized and intense flowering, which favors cross-pollination and reproductive success. These patterns are consistent with those observed in other Brazilian regions with similar climates, such as the Cerrado and Caatinga, evidencing the species' evolutionary adaptations to seasonal environments.