Bud structure and development in trees of a neotropical savanna differing by leaf persistence

The climatic seasonality affects markedly plant organs' development in the neotropical savannas. Essential understandings about bud structure and its development in deciduous, semi-deciduous and evergreen trees are unknown in Cerrado vegetation, the largest neotropical savanna. We aimed to determine the bud development, structure and the relationship between budburst and dry and wet seasons for 15 tree species distributed in leaf phenological groups. We labelled five buds in each of the five adult individuals in tree species of each phenological group at the dry season's peak in July 2016. The labelled buds were monitored every week since their opening up to branch development and leaf production in April 2017. Another group of buds was collected at the dry-wet season transition to determine the bud structure. Deciduous tree species showed preformed leaves in buds, the evergreen trees had neoformed leaves, and semi-deciduous trees had buds with preformed and neoformed leaves. Cataphylls were protecting the buds in all deciduous trees and the semi-deciduous species Eriotheca gracilipes. Budburst in the deciduous species and semi-deciduous except for Guapira noxia and Xylopia aromatica occurred at the dry season's peak. In the evergreen trees, buds developed only after the wet season start. While deciduous and evergreen tree species presented different bud structures and development, the semi-deciduous trees shared the bud traits with phenological groups. We captured distinct growth strategies in groups of trees according to leaf persistence and bud structural and developmental traits.