Anatomical, Histochemical and Cytogenetic Features of <i>Doryopteris triphylla</i> (Pteridaceae)

Abstract

Doryopteris triphylla (Pteridaceae-Cheilanthoideae) grows in xeric habitats in Brazil, Paraguay, Uruguay and Argentina. The aim of this study was to characterize D. triphylla anatomically, histochemically and cytogenetically. For anatomical characterization, rhizomes, roots, petioles and leaves were made and then stained using Safranine-Astra Blue for further observations. Leaf blades were also cleared. For histochemical analysis, leaf cross sections were stained with different reagents to identify glandular trichomes compounds. For cytogenetic characterization, a karyogram was performed using laboratory cultivated roots. Results show a dictyostelic rhizome covered with scales with apical secreting gland; diarch roots; petiole cross-sections show thick cuticle, uniseriate epidermis, parenchymatic cortex cells with thick walls and a vascular bundle with two xylem groups; and hypostomatic fronds with glandular trichomes. Histochemical studies of secretion products of the glandular trichomes were positive for polysaccharides, pectins, lipids, acid lipids, dihydroxyphenols, phenols and flavonoids. Cytogenetically, D. triphylla is described as a diploid species (2n = 60), with chromosomes gradually decreasing in size. The apical glands in scales of rhizomes, the presence of two xylem groups in the vascular bundle in the petiole and the glandular trichomes on the abaxial surface are new contributions to the species. The type of chemical products secreted by glandular leaf trichomes and karyotype estimation is shown for the first time in this species.

Morphological and anatomical adaptations to dry, shady environments in Adiantum reniforme var. sinense (Pteridaceae)

“…In A. reniforme var. sinense, the shaded blades had fewer mesophyll tissues and lower stomatal densities than the unshaded blades, showing that this species displays environmental adaptive plasticity (Givnish, 1988;Ribeiro, Santos & Moraes, 2007;Santos-Silva, Mastroberti & De Araujo Mariath, 2011;Neira et al, 2017;Dematteis et al, 2019;Shah et al, 2019;Baer, Wheeler & Pittermann, 2020).…”

“…(Srivastava & Chandra, 2009), Pteris vittata (Sridhar et al, 2011), Ceradenia sp. (Deroin & Rakotondrainibe, 2015), Blotiella lindeniana (Becari-Viana & Schwartsburd, 2017) and Doryopteris triphylla (Neira et al, 2017). In contrast, epiphytic and xerophytic species, such as Asplenium sp., Pleopeltis macrocarpa and Niphobolus adnascens, had peripheral sclerenchyma layers under the epidermis.…”

“…sinense had a central endodermis and a peripheral sclerenchyma layer underneath the epidermis, which is similar to other ferns (Hernandez-Hernandez et al, 2012), including Anemia (Ribeiro, Santos & Moraes, 2007), Pteris (Bondada, Tu & Ma, 2006;Martínez & Vilte, 2012;Sridhar et al, 2011;Palacios-Rios et al, 2019), Davallia (Ummu-Hani et al, 2013), Blechnum (Noraini et al, 2014), Asplenium (Wetzel et al, 2017), Doryopteris triphylla (Neira et al, 2017) and Pleopeltis macrocarpa (De los Ángeles Lagoria et al, 2018). In Asplenium species, the petiole endodermis was surrounded a sclerenchyma layer (Wetzel et al, 2017), whereas in Doryopteris triphylla, the petiole epidermis had a thick cuticle at the surface (Neira et al, 2017).…”

“…Pteridophytes have evolved various morpho-anatomical features to adapt to terrestrial, xeric, epiphytic, rupicolous and aquatic environments ( Wylie, 1949 ; Zhang et al, 2013 ; Neira et al, 2017 ; Sârbu et al, 2017 ; Wetzel et al, 2017 ); this group is thus taxonomically, evolutionarily, and phylogenically diverse ( Kato & Imaichi, 1997 ; Li et al, 2013 ; Vasco, Moran & Ambrose, 2013 ; Plackett, Di Stilio & Langdale, 2015 ; Harrison & Morris, 2017 ; Huiet et al, 2018 ). Pteridophyte rhizomes have species-or group-specific stele, including the dictyostele of the Monachosorideae and the Polypodiaceae ( Jeffreys, 1903 ; Wardlaw, 1944 ; Wu et al, 1992 ; Srivastava & Chandra, 2009 ; Deroin & Rakotondrainibe, 2015 ; Nopun et al, 2016 ; Becari-Viana & Schwartsburd, 2017 ).…”

“…The leaves have an endodermis, a sclerenchyma layer, and a cuticle as apoplastic barriers ( Ribeiro, Santos & Moraes, 2007 ; De los Ángeles Lagoria et al, 2018 ; Mahley et al, 2018 ; Palacios-Rios et al, 2019 ). Moreover, the morphologies of sun and shade plants are obviously different ( Boardman, 1977 ; Nasrulhaq-Boyce & Mohamed, 1987 ; Givnish, 1988 ; Santos-Silva, Mastroberti & De Araujo Mariath, 2011 ), the leaves of shade plants are large, with large cells, few mesophyll tissues, and decreased stomatal and vein densities ( Ribeiro, Santos & Moraes, 2007 ; Zhang & Wu, 2013 ; Neira et al, 2017 ; Dematteis et al, 2019 ; Shah et al, 2019 ; Baer, Wheeler & Pittermann, 2020 ). In ferns, gymnosperms, and angiosperms, the endodermis or circumendodermal band and the exodermis act as barriers, which restrict water-solute exchange, reduce oxygen loss after submersion, and terrestrial environments ( Ogura, 1972 ; Lersten, 1997 ; Enstone, Peterson & Ma, 2003 ; Hernandez-Hernandez et al, 2012 ; Geldner, 2013 ; Xiang et al, 2019 ; Yang et al, 2011 , 2014 , 2019a , 2019b , 2019c , 2020 ; Zhang et al, 2017 ; Zhang, Yang & Seago, 2018 ).…”