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

A structural review of foliar glands in Passiflora L. (Passifloraceae)

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Cassimiro de Lemos, Renata Cristina [1] ; Silva, Delmira da Costa [2] ; de Albuquerque Melo-de-Pinna, Gladys Flavia [1]
Total Authors: 3
[1] Univ Sao Paulo, Inst Biociencias, Dept Bot, Sao Paulo - Brazil
[2] Univ Estadual Santa Cruz, Dept Ciencias Biol, Salvador - Brazil
Total Affiliations: 2
Document type: Review article
Source: PLoS One; v. 12, n. 11 NOV 14 2017.
Web of Science Citations: 0

Extrafloral glands in Passifloraceae species have aroused the interest of many researchers because of their wide morphological diversity. The present work analyzed the foliar glands on 34 species of Passiflora from samples containing glands in the petiole and foliar blade fixed in 50% solution of formaldehyde-ethanol-acetic acid and stored in a 70% ethanol solution. For anatomical analyses, part of the material was embedded in Paraplast, longitudinally sectioned and double stained with safranin and astra blue. Scanning electron microscopy analysis was also carried out. To analyze the presence of sugars in the secretion of foliar glands, a glucose strip test was used. Based on the results of morphological, anatomical and glucose strip tests, the foliar secretory glands in Passiflora can be grouped into two categories: Type I glands, defined as nectaries, can be elevated or flattened, and can have a sugar content high enough to be detected by the glucose strip test analysis. Type II glands are elevated and did not show a positive reaction to the glucose strip test. From an anatomical viewpoint, glands characterized as extrafloral nectaries show a multi-stratified secretory epidermis, typically followed by two flat layers of nectariferous parenchyma with dense content. Internal to these layers, vascular bundles are immersed in the subsecretory parenchyma and terminate in phloem cells. On the other hand, type II glands show a single layer of elongated secretory epidermal cells. Internal to this single layer, parenchyma and vascular tissue with both phloem and xylem elements can be observed. The analyzed species show a wide diversity of gland shape and distribution, and the combined analysis of morphology, anatomy and preliminary tests for the presence of glucose in the exudate in different Passiflora subgenera suggests the occurrence of two categories of glands: nectaries and resin glands. (AU)

FAPESP's process: 13/07857-4 - Anatomy, ultrastructure and phytochemical of the foliar glands in Passiflora L. (Passifloraceae)
Grantee:Renata Cristina Cassimiro de Lemos
Support Opportunities: Scholarships in Brazil - Doctorate
Grantee:Gladys Flávia de Albuquerque Melo de Pinna
Support Opportunities: Regular Research Grants