Anatomical study on the developing pericarp of selected Rosa species (Rosaceae)
Abstract: “Results of anatomical studies on the developing pericarp of selected wild roses are presented. Using SEM and CLSM, the changes in the pericarp structure of 5 species have been observed during its formation, from the flowering stage to fully ripe achenes. In the morphological development of the pericarp of Rosa species two main phases can be distinguished: the phase of intensive growth of the pericarp during which the fruit achieves its final shape and volume, and the subsequent phase of pericarp ripening when no significant morphological changes in the pericarp occur. Similarly, in the process of the anatomical development of the pericarp two phases are noticeable, however, during both stages, great internal changes proceed in the fruit. The first phase consists of intensive cell divisions and enlargement, gradual thickening of cell walls and formation of all pericarp layers. Due to these changes, the pericarp achieves its final anatomical structure. The second phase, involving the pericarp ripening, is manifested in the modification of cell walls, mainly by their quick thickening, but first of all by their lignification. The lignification of pericarp cell walls begins in the inner endocarp; it proceeds in the outer endocarp, later in mesocarp and finishes in the hypodermal cells of the exocarp. The epidermal cells remain alive the longest and their walls do not (or hardly) become lignified. The death of all cells finishes the pericarp ripening.”
After you reach the link you have to scroll down to the article with the title above.