Advanced search
Start date
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

First Record of Ategmic Ovules in Orchidaceae Offers New Insights Into Mycoheterotrophic Plants

Full text
Alves, Mariana Ferreira [1] ; Pinheiro, Fabio [1] ; Niedzwiedzki, Marta Pinheiro [1] ; Sampaio Mayer, Juliana Lischka [1]
Total Authors: 4
[1] Univ Estadual Campinas, Inst Biol, Dept Biol Vegetal, Sao Paulo, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: FRONTIERS IN PLANT SCIENCE; v. 10, NOV 29 2019.
Web of Science Citations: 0

The number of integuments found in angiosperm ovules is variable. In orchids, most species show bitegmic ovules, except for some mycoheterotrophic species that show ovules with only one integument. Analysis of ovules and the development of the seed coat provide important information regarding functional aspects such as dispersal and seed germination. This study aimed to analyze the origin and development of the seed coat of the mycoheterotrophic orchid Pogoniopsis schenckii and to compare this development with that of other photosynthetic species of the family. Flowers and fruits at different stages of development were collected, and the usual methodology for performing anatomical studies, scanning microscopy, and transmission microscopy following established protocols. P. schenckii have ategmic ovules, while the other species are bitegmic. No evidence of integument formation at any stage of development was found through anatomical studies. The reduction of integuments found in the ovules could facilitate fertilization in this species. The seeds of P. schenckii, Vanilla planifolia, and V. palmarum have hard seed coats, while the other species have seed coats formed by the testa alone, making them thin and transparent. P. schenckii, in contrast to the other species analyzed, has a seed coat that originates from the nucellar epidermis, while in other species, the seed coat originates from the outer integument. (AU)

FAPESP's process: 15/26479-6 - Vegetative structure of the achlorophyllous orchid Pogoniopsis schenckii (Vanilloideae) and its interaction with mycorrhizal fungi
Grantee:Juliana Lischka Sampaio Mayer
Support type: Regular Research Grants