Karyotype Report
Karyological investigation of four endemic Hyacinthella species from Turkey
2024 年 89 巻 1 号 p. 53-56
詳細
2024 年 89 巻 1 号 p. 53-56
The chromosome numbers and karyotypes of four endemic species belonging to the genus Hyacinthella distributed in Turkey have been examined. These taxa encompass H. campanulata K. Perss. & Wendelbo, H. acutiloba K. Perss. & Wendelbo, H. siirtensis B. Mathew, H. micrantha (Boiss.) Chouard. The chromosome numbers of investigated taxa have been ascertained as 2n=2x=18 (H. acutiloba and H. campanulata) and 2n=2x=22 (H. micrantha and H. siirtensis). The mean chromosome length varies between 1.65 µm (H. micrantha) and 6.37 µm (H. siirtensis). Haploid chromosome lengths varied between 25.39 µm (H. micrantha) to 31.56 µm (H. siirtensis) among these species. The arm ratio was determined as a minimum of 1.06 in H. acutiloba, and as a maximum of 4.48 in H. siirtensis, whereas the lowest relative length was observed in H. siirtensis (6.08%), and the highest relative length was found in H. siirtensis (20.18%). Karyotype analysis indicated that Hyacinthella taxa typically possessed median (m), submedian (sm), and subterminal (st) chromosomes.
The genus Hyacinthella Schur has been transferred from the family Hyacinthaceae to Asparagaceae. Asparagaceae is well-defined based on the fruit and stamen characteristics. It differs from the related families Liliaceae and Colchicaceae by its baccate fruit and introrse stamens (Baker 1875). The family is represented by nearly 3,600 species included in 143 genera in the world. The species of the family used as vegetable, ornamental, and medicinal plants are distributed naturally in temperate, tropical, and sub-tropical regions (The Plant List; http://www.theplantlist.org/browse/A/Asparagaceae). These members of the family are reported in the Flora of Turkey as 19 genera and 182 species. Hyacinthella genus includes 13 species, most of which are distributed in Southeastern Asia, 3 of which are distributed in South-eastern Europe (Persson and Wendelbo 1981, 1982, Persson and Persson 1992, 2000). It is represented by 12 species, 10 of which are endemic to Turkey (Ekim et al. 2012).
In previous literature, chromosome numbers of species of Hyacinthella genus were reported as 2n=16, 18, 20, 22, 24, and 60. Persson and Wendelbo (1981, 1982) analyzed a single plant of H. dalmatica from a commercial source and found 2n=2x=20. Trinajstic and Lovašen-Eberhardt (1984) analyzed three plants from natural populations (Konavle and Hvar in Croatia) and found four different cytotypes, some with one, two, or three B chromosomes, and chromosome number 2n=2x=18 as the most frequent one. In the latest revision of the Balkan taxa of Hyacinthella, they expressed their uncertainty regarding the chromosome number of H. dalmatica, suspecting variation from 2n=18–20, even within the same population (Trinajstic and Lovašen-Eberhardt 1984).
Chromosome number has been determined in most of the Hyacinthella species distributed in Turkey. No polyploid number was found in the Hyacinthella, whose basic chromosome number varies between x=8–12. Chromosome counts were made in 11 of the 12 Hyacinthella species registered in Turkey. Several studies determined the chromosome numbers in the examined taxa as 2n=16 in one species, 2n=18 in five species, 2n=22 in four species, and 2n=24 in one species (Persson and Wendelbo 1982, Persson and Persson 1992, Johnson and Brandham 1997). No karyomorphological studies have been conducted in any of these species.
Persson and Wendelbo (1982) in two-part cytological and taxonomic studies on Hyacinthella species distributed in Southwest Asia, H. lineata (Steud. ex Schult. & Schult J.) Chouard, 2n=16 for (three populations), H. acutiloba K.Perss. & Wendelbo (two populations), H. campanulata (two populations), H. glabrencens (Boiss) K.Perss. & Wendelbo (a population), H. heldreichi (Boiss) Chouard, (five populations), H. hispida (J. Gay) Chouard (a population) for 2n=18, H. micrantha (Boiss) Chouard (a population), H. heldreichi micrantha (a population), H. siirtensis B. Mathew (a population) for 2n=22, H. nervosa (Bertol.) Chouard (a population) determined the chromosome number of 2n=24.
Johnson and Brandham (1997) reported 2n=18 for H. acutiloba and H. heldreichi, 2n=20 for H. glabrencens, 2n=22 for H. lazulina. Puizina et al. (2003) reported 2n=20 chromosome number in a karyological study of H. dalmatica (Lallem).
This work aimed to examine the chromosome number and analyze the karyotype of four endemic Hyacinthella species from Turkey and to bring the karyotype data to the literature.
Plant materials of four Hyacinthella species were collected from natural habitats during the fruiting season between 2022 and 2023. Species names, their localities, geographical positions, altitude, and voucher numbers are presented in Table 1. The voucher specimens were deposited at the Herbarium of Firat University.
| Taxa | Locality | Voucher number |
|---|---|---|
| H. acutiloba | B7/Malatya: Yazıhan, Girmana Canyon, rocky places, 1,063 m | H.Eroglu 1593 |
| H. campanulata | C4/Konya: Meram, Konya-Beyşehir road, Altınapa Dam, 1,310 m | H.Eroglu 1719 |
| H. micrantha | A4/Kastamonu: Kastamonu University Campus, Pinus yards, 820 m | H.Eroglu 1450 |
| H. siirtensis | C8/Mardin: Artuklu, between Mardin and Diyarbakır, 1,138 m | H.Eroglu 1524 |
The karyological studies are conducted on the meristematic cells of seven bulbs of each species. The bulbs were germinated at 25°C. The actively growing root tips were pretreated with 0.05% colchicine for 4 h at room temperature. Afterward, the root tips were fixed with Carnoy fixative (1 : 3 glacial acetic acid–absolute ethanol) for at least 24 h at 4°C, hydrolyzed in 1 M HCl at 60°C for 10–15 min, then rinsed in tap water for 3–5 min. Finally, they were stained in a Feulgen reagent for 1 h and mounted in 45% acetic acid (Kiran et al. 2012). Digital microphotographs from at least five well-spread metaphase plates were taken using an Olympus BX51 microscope and an Olympus Camedia C-4000 digital camera.
The number of somatic chromosomes, chromosome length, and haploid chromosome length, were measured and arm ratio and relative length were calculated. The karyotype formula was determined based on the centromere position using a system of Levan et al. (1964). The idiograms of these taxa are arranged in decreasing lengths according to the chromosome size in the metaphase (Martin et al. 2009).
The chromosome number, chromosome length range, haploid chromosome length, arm ratio, relative length, and karyotype formula were determined from 14 metaphase cells in each species and given in Table 2. Metaphase chromosomes are shown in Fig. 1 and idiograms in Fig. 2.
| Taxa | 2n | Chromosome length (µm) | Haploid chromosome length (µm) | Arm ratio | Relative length (%) | Karyotype formula | |||
|---|---|---|---|---|---|---|---|---|---|
| Min | Max | Min | Max | Min | Max | ||||
| H. acutiloba | 18 | 2.24 | 4.76 | 27.63 | 1.06 | 2.63 | 8.10 | 17.22 | 8m+sm |
| H. campanulata | 18 | 2.15 | 4.69 | 25.46 | 1.11 | 3.64 | 8.44 | 18.42 | 7m+sm+st |
| H. micrantha | 22 | 1.65 | 3.64 | 25.39 | 1.08 | 2.42 | 6.49 | 14.33 | 10m+sm |
| H. siirtensis | 22 | 1.92 | 6.37 | 31.56 | 1.15 | 4.58 | 6.08 | 20.18 | 7m+3sm+st |
(A) H. acutiloba, (B) H. campanulata, (C) H. micrantha, (D) H. siirtensis. Scale bars=10 µm.
(A) H. acutiloba, (B) H. campanulata, (C) H. micrantha, (D) H. siirtensis..
The somatic chromosome number of H. acutiloba was 2n=2x=18 (Fig. 1A). The karyotype formula was 8m+sm. The chromosome length ranged from 2.24 to 4.76 µm and the haploid chromosome length was 27.63 µm. Arm ratios were 1.06–2.63 and relative lengths were 8.10–17.22% (Table 2). The idiogram is given in Fig. 2A.
The somatic chromosome number of H. campanulata was 2n=2x=18 (Fig. 1B). The karyotype formula was 7m+sm+st. The chromosome length ranged from 2.15 to 4.69 µm and the haploid chromosome length was 25.46 µm. Arm ratios were 1.11–3.64 and relative lengths were 8.44–18.42% (Table 2). The idiogram is given in Fig. 2B.
The somatic chromosome number of H. micrantha was 2n=2x=22 (Fig. 1C). The karyotype formula was 10m+sm. The chromosome length ranged from 1.65 to 3.64 µm and the haploid chromosome length was 25.39 µm. Arm ratios were 1.08–2.42 and relative lengths were 6.49–14.33% (Table 2). The idiogram is given in Fig. 2C.
The somatic chromosome number of H. siirtensis was 2n=2x=22 (Fig. 1D). The karyotype formula was 7m+3sm+st. The chromosome length ranged from 1.92 to 6.37 µm and the haploid chromosome length was 31.56 µm. Arm ratios were 1.15–4.58 and relative lengths were 6.08–20.18% (Table 2). The idiogram is given in Fig. 2D.
Chromosome lengths show wide variation among species. The mean chromosome length varies between 1.65 µm (H. micrantha) and 6.37 µm (H. siirtensis). Haploid chromosome length ranges from 25.39 µm (H. micrantha) to 31.56 µm (H. siirtensis). The arm ratio was determined as a minimum of 1.06 in H. acutiloba, and as a maximum of 4.48 in H. siirtensis, whereas the lowest relative length was observed in H. siirtensis (6.08%), and the highest relative length was found in H. siirtensis (20.18%).
Species of Hyacinthella genus generally have varying basic chromosome numbers. According to the literature, H. lineate had 2n=16 (Persson and Wendelbo 1982), H. heldreichii (Boiss.) Chouard had 2n=18 (Johnson and Brandham 1997), H. hispida (J. Gay) Chouard had 2n=18 (Persson and Persson 1992), H. glabrescens (Boiss.) K. Persson & Wendelbo had 2n=18 (Persson and Persson 1992) and 2n=20 (Johnson and Brandham 1997), H. leucophaea (C. Koch) Schur had 2n=20 (Johnson and Brandham 1997), H. atchleyi had 2n=20 (Persson and Wendelbo 1982, Speta 1982), H. pallens Schur had 2n=20 (Persson and Wendelbo 1982), H. pallasiana (Stev.) Losinsk had 2n=20 (Persson and Wendelbo 1982), H. atropatana (Grossh.) Mordak & Zakharyeva had 2n=22 (Pogosian 1997), H. lazulina K. Perss. & J. Perss. had 2n=22 (Persson and Persson 1992, Johnson and Brandham 1997), H. millingenii had 2n=22 (Persson and Wendelbo 1982), H. persica had 2n=22 (Speta 1982), H. venusta K. Persson had 2n=22 (Persson 2000), H. nervosa (Bertol.) Chouard had 2n=24 (Persson and Persson 1992), H. dalmatica Chouard had 2n=60 (Persson and Persson 2000).
In previous studies, the chromosome number of H. acutiloba species was reported as 2n=18 (Persson and Persson 1992, Ozhatay 2002, Gedik and Kocabas 2020). Somatic chromosome number of H. campanulata has been reported as 2n=18 (Persson and Persson 1992, Ozhatay 2002, Coskuner 2019). In this study, the chromosome number of both species was determined as 2n=18.
To date, only one study has been conducted on the chromosome number of H. micrantha. In the study conducted by Persson and Wendelbo (1982), the chromosome number of the species was reported as 2n=22. According to literature (Persson and Persson 1992, Ozhatay 2002), H. siirtensis had 2n=22. Our research yielded the same results for both species (2n=22). With this study, we contribute to the search for karyologically understudied species to expand the karyological knowledge of the genus Hyacinthella.
This article was produced from the master’s thesis of Selçuk Kılıç, a student of Firat University, Institute of Science.
Hüseyin Eroğlu and Süleyman Mesut Pınar provided the plant materials and identified them. Yasar Kiran planned the study. Selçuk Kılıç, Gulden Dogan, and Yasar Kiran conducted cytogenetic studies. Gulden Dogan also wrote the article.
