Seed macro and micro morphology of the selected Nigella (Ranunculaceae) taxa from Turkey and their systematic significance

Abstract

Macro and micromorphological properties of intact and mature seeds of 12 taxa (species and varieties) belonging to Nigella L. (Ranunculaceae) was investigated using light and scanning electron microscopy. Material studied covers 11 species of 15 Turkish Nigella. Studied taxa were divided into two types. Type I has ovate to orbicular seeds that includes four species. Type II has triquedrous seeds and includes seven species. Type II was subdivided into two. Type IIa has triquedrous to subpyramidal seeds (five species) and Type IIb has triquedrous to subglobose seeds (two species). Further segregation was performed micromorphologically and an identification key of studied Nigella taxa was given. Studied Nigella taxa have a diverse macro and micromorphological characters that utilize to separate them from each other to assess the systematics of Nigella.

Numerical analyses of seed morphology and its taxonomic significance in the tribe Nigelleae (Ranunculaceae)

“…N. damascena and N. elata, show up together on the same branch in our analysis and this relationship is also supported by the PCoA plot. Taken together, Heiss et al (2011), Dadandı et al (2009) and in this study have revealed only one micromorphological character that differ between these two species: N. damascena is characterized by a distinct central mucro on the seed surface cells while N. elata has an indistinct mucro mostly at the center but partly also on the periphery of the periclinal walls. Dadandı et al (2009) emphasized only the indistinct mucro on the periphery, but we observed that some seed cells of N. elata have a mucro both at the center and on the periphery of the wall.…”

“…Taken together, Heiss et al (2011), Dadandı et al (2009) and in this study have revealed only one micromorphological character that differ between these two species: N. damascena is characterized by a distinct central mucro on the seed surface cells while N. elata has an indistinct mucro mostly at the center but partly also on the periphery of the periclinal walls. Dadandı et al (2009) emphasized only the indistinct mucro on the periphery, but we observed that some seed cells of N. elata have a mucro both at the center and on the periphery of the wall. Other morphological characters of the fruits and petals are used to distinguish these species, but seed micromorphology can be added as a new diagnostic characters.…”

“…Seed morphological characters have been considered significant traits for distinguishing among all taxonomic ranks in different plant families (Barthlott 1981, Arroyo-Cosultchi et al 2006, Fagundez and Izco 2011, Antkowiak et al 2018, Ghimire et al 2018). In addition, seed coat morphology, especially micromorphology, have provided useful taxonomic information for different genera of Ranunculaceae (Cappelletti and Poldini 1984, Karcz and Tomzcok 1987, Luo et al 2005, Dadandı et al 2009, Wang et al 2009, Antkowiak et al 2010, Emadzade et al 2010, Heiss et al 2011, Ghimire et al 2015, 2016. Half of the sections of Consolida (Constantinidis et al 2001) and tribe Delphinieae (Ghimire et al 2015) are well supported based on only seed characters.…”

“…(including Garidella and Komaroffia) and the phylogenetic implications of their seed morphology and anatomy. Another study of Nigella seeds including 12 taxa was conducted by Dadandı et al (2009) to understand the infrastructure of seeds and contribute to resolving the taxonomy of the genus.…”

Recent advances in the identification and the study of composition and activities of medicinal plants

“…Segregation was performed micromorphologically. Studied Nigella taxa have a diverse macro-and micro-morphological characters that are utilized to separate them from each other to assess the systematics of Nigella [15].…”