Abstract
A botanical entity can be regarded as an ordered succession of botanical entities of a lower level of organisation (ex: a growth unit can be described as a succession of metamers). For each botanical entity, it is possible to measure several variables that reflect its characteristics (length of internode, type of axillary production). The succession of the values taken by one or several measured variables is then called “sequence of botanical events”. The recent work carried out on fruit and forest trees led to the development of a statistical approach dedicated to the analysis of sequence samples ranging from exploratory analysis to the building of Markovian processes. The objective of this thesis is (i) to evaluate the relevance of an approach coupling architectural analysis and analysis of sequences extracted from measured architectures, (ii) to bring a new vision and comprehension of the growth, ramification and flowering phenomena by the use of adapted statistical models and (iii) to analyse the possible applications of comparison of sequences and models in the study of the influence of the environment and the characterisation of architectural plasticity. These problems are illustrated by (i) the study of the branching pattern on various growth unit types belonging to mono- or polycylic annual shoots of red oak (Quercus rubra), (ii) synchronism of branching and flowering processes in Cecropia obtusa and (iii) the study of the evolution of phyllotaxy and branching pattern during ontogeny on several species of Cupressus. The results show that the distribution of the axillary productions on a bearing parent entity is not random but is generally organised as a succession of homogeneous zones or shows repeated patterns at a more local level. The subjacent mechanisms potentially responsible for the revealed patterns at various scales and the interest to take into account structural information of the trees in the measurement and the statistical analysis of the data are discussed