  Understanding the emergence of biological structures and their changes is a
complex problem. On a biochemical level, it is based on gene regulatory
networks (GRN) consisting on interactions between the genes responsible for
cell differentiation and coupled in a greater scale with external factors. In
this work we provide a systematic methodological framework to construct
Waddington's epigenetic landscape of the GRN involved in cellular determination
during the early stages of development of angiosperms. As a specific example we
consider the flower of the plant \textit{Arabidopsis thaliana}. Our model,
which is based on experimental data, recovers accurately the spatial
configuration of the flower during cell fate determination, not only for the
wild type, but for its homeotic mutants as well. The method developed in this
project is general enough to be used in the study of the relationship between
genotype-phenotype in other living organisms.
