부산대학교 도서관

Here we present a detailed description of the secretory tissues found in the gynostemium and ovary of species representing both early and late diverging clades of Pleurothallidinae. The rostellum acts in pre-anthesis events, secreting a mucilaginous exudate closely related to the development and secretory phase of cells from the transmitting tissue. A new interpretation of the secretory dynamics of transmitting tissue cells is proposed considering the transversal stratification of these secretory cells in relation to the length of the gynostemium. The transmitting tissue is composed of cells showing two phases of secretion, the first consisting of mucilage and the second of lipophilic compounds. These phases are related to the position of these cells in the cortical or medullary region of the transmitting tissue, respectively. The structuring of the transmitting tissue cells explains secretion dynamics in this wet, detached stigma type. The presence of lipophilic compounds can be related to self-incompatibility sites described in some species of Pleurothallidinae. Regarding the secretory tissues of the ovary, we describe the first occurrence of papillae in the locule acting as an obturator in Orchidaceae. [ABSTRACT FROM AUTHOR]