Seed structure of some taxa of the genus Crocus L. (Iridaceae) series Crocus

Abstract

distributed from West Europe and Northwest Africa to West China, with the center of species diversity in the Balkan Peninsula and Turkey. Turkey is the richest country with 137 Crocus taxa (Harpke et al., 2012; Ruksans, 2017). Different conventional morphological features used in Crocus taxonomy with regards to possibly distinguishing monophyletic groups within the genus have been reported in the literature (Harpke et al., 2012, 2014; Carta et al., 2015), in which it was found that none of the traditional morphological features were suitable for discriminating Crocus sections or series. This status has caused some problems in their classification; therefore, additional characteristics that can assist the existing diagnostics are needed for the classification of Crocus taxa. Crocus seed color, structure, and surface sculpture are of much importance in terms of taxonomical applications (Maw, 1886). However, with the exception of a few studies (Kujat and Rafiński, 1978; Grilli Caiola et al., 2010; Carta et al., 2015), Crocus seed has not been a popular research subject. Mathew (1982) attributed this situation to the fact that the capsules and seeds of crocuses flowering in either autumn or spring reach maturity during April and May. According to our experiences from field observations, it is hard to find and collect capsules on the ground when vegetation is dense and tall. Therefore, Crocus seed studies require the cultivation of related taxa and capsule and seed harvesting should be done carefully. Seeds and fruits may possess various macro-and micromorphological structures that can provide valuable information for plant taxonomy. The shape, color, size, and especially microstructure (including anatomical features) of the seeds and fruits are valuable information for plant systematics (Kerndorff et al., 2015). There have been many plant epidermal surface analyses using scanning electron microscopes (SEMs). According to Barthlott (1981), surface characteristics can basically be divided into 4 main groups: 1) cellular arrangement, 2) shape of the cells, 3) relief of the outer cell walls, and 4) epicuticular secretions. These characteristics vary widely among species and at the family level, and are not easily affected by environmental conditions. Moreover, Kerndorff et al. (2015) stated that the microstructures of Crocus seed testae are very taxonomically valuable, and just this character alone can be adequate for a systematic grouping of the genus. In addition, the seed anatomical characters are generally as useful as the morphological characters for plant identification and are frequently used in the discrimination of closely related taxa (Karamian et al., 2012; Karaismailoğlu, 2015).

Seed Morphological and Anatomical Structures as Taxonomy Tool for Turkish Hyacinthella Schur (Asparagaceae) Taxa

“…4). The characters in statistical analysis were utilized seed colour: black (1), brown (2); seed shape: triangularis (3), circularis (4), ellipticus (5), ovatus (6), ellipticus-late (7); seed size: length (8), width (9), length/width (10); seed ornamentation type: rugose (11), reticulate-pusticulate (12), verrucate (13), tuberculate (14), ruminate (15), reticulate-foveate (16), alveolate (17); anticlinal cell wall: unclear (18), at (19), raised (20), sunken (21); periclinal cell wall: unclear (22), concave (23), convex (24); epidermal cell structure: unclear (25), polygonal (26), alveolar (27); anatomical structure of epidermis: crushed (28), at (29), polygonal (30); presence of subepidermis layer (31); anatomical structure of subepidermis: at (32), polygonal (33); testa thickness (34); cotyledon size: length (35), width (36); embryo shapes: elongated (37), ellipticus (38), ovatus (39), circularis (40); embryo size: length (41), width (42). The dissimilarity matrix of the examined species was formed with MVSP (Kovach 2007) (Table 4).…”

Taxonomic significance of morphological and elemental characteristics of achenes of Artemisia genus from Turkey

“…vanensis (tuberculate) taxa (Figure 2 and Table 3). Also, previous seed or fruit surface examinations have displayed that the types and arrangements of the anticlinal and periclinal cell walls are diagnostic features in the formation of inter‐taxa relations (Barthlott, 1981; Eroğlu et al, 2022; Karaismailoğlu et al, 2018; Özbek et al, 2018). The kinds of anticlinal and periclinal cell walls, and epidermal cell forms of the examined taxa disclose differences among taxa.…”

Taxonomical remarks on Allium yamadagensis Yıldırım & Ekşi, (Amaryllidaceae) from Turkey

“…Seed morphology provides useful systematic characters at various taxonomic levels in the genus Allium [7,8,9,10,11,12,13,14,15,16,17].…”