Bud structure, time of budbreak and crown architecture in woody species from Cerrado and seasonal forests of Brazil.

Different light intensities in cerrado stricto sensu (CSS) and semideciduous seasonal forests (SSF) can result in distinct morphological responses among woody species. This research evaluated the size and bud composition, budbreak time, and crown architecture of woody species in response to precipitation and varying light intensities in these two environments. The study was conducted in CSS (19°57'29″ S and 44°25'29″ W) and an SSF fragment (19°53'84″ S and 44°25'56″ W) in Minas Gerais, Brazil. The research focused on four species: Miconia albicans and Xylopia aromatica, which occur in both environments, as well as Bauhinia cfr. ungulata (CSS) and B. cfr. rufa (SSF). Shoots from the main axis were manually dissected, and budbreak times were recorded. Crown architecture was evaluated based on diagrams of the vegetative above-ground structure, excluding leaves. Light intensities was measured with a luxmeter at the crown's apex, interior, and base. Shoots were larger and had more preformed organs in CSS than in SSF trees. Trichomes were observed on shoots of all CSS and SSF trees. The number of cataphylls varied: B. cfr. ungulata had one, B. cfr. rufa had 1-3, while compound buds of X. aromatica averaged 5.4 in CSS and 3.7 in SSF. Simple buds of X. aromatica and all M. albicans buds lacked cataphylls. Budbreak occurred in September for M. albicans (CSS and SSF), October for B. cfr. ungulata, Juy-October for X. aromatica and August-October for B. cfr. rufa. A positive correlation between budbreak and rainfall was recorded only for B. cfr. ungulata. Despite differences in bud size and composition between environment, these didn't result in distinct crown architectures. The findings highlight that tropical woody species with cataphyll-protected buds are as common as in temperate regions. Further research is needed to explore phylogenetic traits and the ecological role of cataphylls in tropical species.