A amplitude do conceito de fenótipo estendido em galhas de insetos

Abstract

Galls develop by the reprogramming of plant cells, so that cell lineages assume forms and functions different from that of the standard ontogenesis of the host organ. The way galling insects modulate cell behaviour in the different host plants is unique, and determines patterns of cell phenotypes in their galls. Such cellular phenotypic patterns lead to the organogenesis of different gall morphotypes, i. e., the extended phenotypes of the gall inducers. Nevertheless, convergent gall shapes are observed for different galling insect – host plant systems. Systems in which galls are morphologically convergent, and both the insects and host plants are phylogenetically related, some questions arise: Are the cellular mechanisms involved in the generation of similar conservative forms? Are there patterns of structural and metabolic alterations that confer unique functionalities to each gall? Can the galls be considered the extended phenotypes of their inducers at the cellular and subcellular levels? This thesis discusses different cellular mechanisms for the determination of forms and functions in plant tissues, under the perspective of gall development, a plant neo-ontogenesis.