Micromorphology and histochemistry of leaf trichomes of Salvia aegyptiaca (Lamiaceae)

Abstract

We performed a comprehensive study of trichomes considering the medicinal importance of the essential oils produced in glandular trichomes of Salvia aegyptiaca L. and lack of data about leaf trichome characteristics. Micromorphological and histochemical analyses of the trichomes of S. aegyptiaca were carried out using light and scanning electron microscopy. We report that the leaves contained abundant non-glandular unbranched trichomes and two types of glandular trichomes, peltate and capitate, on both leaf surfaces. The abaxial leaf side was covered with numerous peltate and capitate trichomes, while capitate trichomes were more abundant on the adaxial leaf side, where peltate trichomes were rarely observed. The non-glandular trichomes were unicellular papillae and multicellular, uniseriate, two-to-six-celled, erect or slightly leaning toward the epidermis. Peltate trichomes were composed of a basal cell, a short cylindrical stalk cell and a broad head of eight secretory cells arranged in a single circle. Capitate trichomes consisted of a one-celled glandular head, subtended by a stalk of variable length, and classified into two types: capitate trichomes type I (or short-stalked glandular trichomes) and capitate trichomes type II (or long-stalked glandular trichomes). Histochemical tests showed that the secreted material in all types of S. aegyptiaca glandular trichomes was of a complex nature. Positive reactions to lipids for both types of glandular trichomes were obtained, with especially abundant secretion observed in peltate and capitate trichomes type II.

Effect of salicylic acid foliar application on growth, glandular hairs and essential oil yield in Salvia officinalis L. grown under zinc stress

“…The peltate glands release their contents to outside by bursting of the cuticle. Chez genus Salvia, Corsi and Bottega [49]; Serrato-Valenti et al [50]; Bisio et al [5] and Janošević et al [51] stated that at the time of secretion, a large space in which materials accumulate has developed through the elevation of the cuticle and the outermost layer of the walls of the secretory cells.…”

Sites of secretion of bioactive compounds in leaves of Dracocephalum moldavica L.: anatomical, histochemical, and essential oil study

“…As in our previous series of studies (Dmitruk and Weryszko-Chmielewska 2010), we have found high morphological diversity of cells building the head of these trichomes. Such trichomes have also been described in Isodon rubescens (Liu and Liu 2012), Salvia aegyptica L. (Janošević et al 2016), and Marrubium vulgare (Haratym and Weryszko-Chmielewska 2017). The non-glandular trichomes in D. moldavica were uniseriate, uni-or multicellular (1-4 cells), erect or curved, and commonly with swollen basal cells.…”

“…D. moldavica leaves, stems, and flowers are covered by numerous glandular and non-glandular trichomes (Dmitruk and Weryszko-Chmielewska 2010), as in many other species from the family Lamiaceae (Ascensão et al 1995;Corsi and Bottega 1999;Chwil et al 2016;Janošević et al 2016;Haratym and Weryszko-Chmielewska 2017;Tozin and Rodrigues 2017). Previous studies of D. moldavica trichomes on the leaves conducted by other researchers with the use of the available methods, mainly LM, demonstrated different findings.…”

Micromorphological and anatomical characteristics of Salvia amplexicaulis Lam., S. jurisicii Košanin and S. ringens Sibth. & Sm. (Lamiaceae)

“…Plant species that contain glandular trichomes produce relatively large amounts of bioactive compounds which include highly concentrated phytochemicals with biological activities of interest to many industries (Dyubeni and Buwa, 2011). In the recent decades, many researchers were focused on the micromorphological characterization of trichomes of Salvia L. species (Bisio et al 1999;Corsi and Bottega 1999;Özdemir and Şenel 1999;Krstić et al 2006;Özkan and Soy 2007;Özkan 2008;Özkan et al 2008;Schrimiderer et al 2008;Aktaş et al 2009;Anačkov et al 2009;İlçim et al 2009;Mayekiso et al 2009;Moon et al 2009a;Baran et al 2010aBaran et al , 2010bKahraman and Doğan 2010;Kahraman et al 2010aKahraman et al , 2010bBercu et al 2012;Dyubeni and Buwa 2012;Salimpour et al 2012;Shirsat et al 2012;Al Sheef et al 2013;Celep et al 2014;Celep et al 2015;Janošević et al 2016;Gul et al 2019b).…”