Nordic Journal of Botany 27: 13, 2009 doi: 10.1111/j.1756-1051.2009.00383.x, # The Authors. Journal compilation # Nordic Journal of Botany 2009 Subject Editor: Brita Stedje. Accepted 6 February 2009

Chromosome numbers of three Calligonum species (Polygonaceae)

Gulnur Sabirhazi and Bo-Rong Pan

G. Sabirhazi ([email protected]) and B.-R. Pan, Inst. of Ecology and Geography, The Chinese Academy of Sciences, CN830011 Urumqi, PR .

The chromosome number 2n36 for Calligonum korlaense Z. M. Mao and the chromosome number 2n18 for Calligonum yengisaricum Z. M. Mao and Calligonum ruoqiangense Liou f. is reported for the first time.

The genus Calligonum L. belongs to the family Polygona- specimens were identified as C. korlaense, C. yengisaricum, ceae and has 35 species in the world, distributed in North C. ruoqiangense according to Bao and Grabovskaya- Africa, south Europe and Asia (Mao and Pan 1986). With Borodina (2003). Vouchers were deposited in the herbar- 23 species of Calligonum L., China is the eastern-most ium XJBI (herbarium Xinjiang Inst. of Ecology and part of the distribution range of the genus (Bao and Geography, Chinese Academy of Sciences). Grabovskaya-Borodina 2003). The Chinese species are Each sampled population included 1030 individuals. found in Nei Monggol, Gansu, Qinghai and Xinjiang. A minimum of 30 well spread cells were counted for each 22 species have been found in Xinjiang (Mao 1992). population, and root-tip cells from seed sprouts were Calligonum species have been playing a key role in the analyzed in at least 5 cells per seedling. Seeds were soaked stability of natural and artificial desert vegetation ecosys- in water for 48 h and then washed with distilled water for tems of China (Mao and Pan 1986). 12 min and placed in Petri dishes with moistened gauze The species of Calligonum L. are mainly shrubs or sub- for germination in an artificial climate chamber. shrubs, much branched with woody branches without Radical meristems from the germinated seeds were spines and herbaceous branchlets of the current year with treated with 0.2% colchicine for 24 h at room temperature leaves and flowers. The leaves are simple, opposite, nearly and then fixed in Carnoy’s solution (absolute ethanol: acetic sessile, linear or scale-like, united with ocrea at base or free acid, 3:1) for 424 h. They were washed in 50% ethanol (Bao and Grabovskaya-Borodina 2003). and distilled water, hydrolyzed in l mol l1 HCl at 608C There are few cytogenetic studies of Calligonum, and for 1520 min, softened in 45% acetic acid for 10 min and such studies are particularly difficult to perform due to the then stained in modified Carbol fuchsin for 524 h. small chromosome size. However, the basic number x9 Photomicrographs of metaphase cells were taken with an and the actual chromosome number has been recorded of OLYMPUS (BX51) photography microscope for chromo- 16 Calligonum L. (Mao et al. 1983, Wang and Yang 1985, some number counting. Wang and Guan 1986; Table 1). In the present study, chromosomes counts for C. korlaense Z. M. Mao, C. yengisaricum Z. M. Mao and Results and discussion C. ruoqiangense Liou f. are reported for the first time, based on material collected from different zones of the Tarim All observations showed that C. korlaense have a somatic basin in the Xinjiang Province. number of 2n36 whereas C. yengisaricum and C. ruoqiangense have a somatic number of 2n18. Represen- tative chromosome photographs of mitotic materials of Material and methods three species are shown in Fig. 13. These chromosome counts are all reported for the first time. The material of this study was collected from different The chromosome number 2n36 for C. korlaense and zones in the , Xinjiang, China (Table 2). The 2n18 for C. yengisaricum and C. ruoqiangense is

1 Table 1. Previously published chromosome numbers of Calligonum L. species from the Xinjiang Province, China.

Published as: CN Reference (all from China)

C. junceum (Fish. et Mey.) 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. leucocladum (Schrenk) Bge. 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. aphyllum (Pall) Gurke 2n36 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. rubicundum Bge. 2n36 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. cordatum Eug. Kor. ex N. Pavl 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. densum Borszcz 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. klementxii A. Los. 2n18 (24) Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. mongolicum Turcz. 2n18 (27) Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. pumilum A. Los. 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. ebi-nuricum Ivanova 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. arborescents Livt. 2n18 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. caput-medusae Schrenk. 2n36 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. roborovskii A. Los. 2n36 Mao et al. (1983), Wang and Yang (1985), Wang and Guan (1986) C. gobicum (Bge.) A. Los. 2n18 Wang and Yang (1985), Wang and Guan (1986) C. squarrosum. N. Pavl. 2n36 Wang and Guan (1986) C. chinese A. Los. 2n18 Wang and Guan (1986)

Table 2. Sites and dates of collection for the Calligonum material used in the present study.

Species name Collection site (Tar- Latitude Longitude Altitude (m) Date Voucher no. im basin)

C. korlaense Luntai County 41849?52.8ƒ 83855?1.4?? 1019 21 Jun 2005 L06621 C. yengisaricum Shache County 38831?56.4ƒ 76843?42.5?? 1304 25 Jun 2005 S05625 C. ruoqiangense 38845?51.7ƒ 88811?24.7?? 1327 12 Oct 2007 R071012

Fig. 1. Photomicrograph of somatic metaphase chromosomes and diagrammatic line drawing of chromosomes of Calligonum korlaense. 1) photomicrograph of somatic metaphase chromosomes, 2) diagrammatic line drawing of chromosomes. congruent with the basic number x9, previously reported study, there are 19 species of the genus Calligonum in the by Mao et al. (1983), Wang and Yang (1985), Wang and Xinjiang Province, for which the chromosome number has Guan (1986). Including the three species in the present been determined.

2 Fig. 2. Photomicrograph of somatic metaphase chromosome and diagrammatic line drawing of chromosomes of Calligonum. Yengisaricum. 1) photomicrograph of somatic metaphase chromosomes, 2) diagrammatic line drawing of chromosomes.

Fig. 3. Photomicrograph of somatic metaphase chromosome and diagrammatic line drawing of chromosomes of Calligonum ruoqiangense. 1) photomicrograph of somatic metaphase chromosomes, 2) diagrammatic line drawing of chromosomes.

Unlinked Reference Mao 1992. Please provide further details. Mao, Z. M. 1998. Flora Xinjiangensis. Vol. 1. Xinjiang Science, Mao 1998 Technol. and Hygiene Publ. House, Urumqi, pp. 118133. Mao, Z. M. et al. 1983. Study on chromosome number and anatomy of young branches of Calligonum of Xinjiang in relation to the evolution of some species of the genus. Acta References Phytotax Sin. 21: 4449. Wang, C. G. and Yang, G. 1985. Investigation of chromosome Mao, Z.-M. and Pan, B.-R. 1986. The classification and number and chromosomal ploidy of Calligonum in Xinjiang. distribution of the genus Calligonum L. in China. Acta Arid Zone Res. 1: 6264. Phytotax Sin. 24: 98107. Wang, C. G. and Guan, S. C. 1986. The geographical distribu- Bao, B.-J. and Grabovskaya-Borodina, A. E. 2003. Calligonum L. tions of chromosomes of Calligonum in Xinjiang. Arid Zone In: Flora of China. Vol.5. Science Press, , Miss. Bot. Res. 2: 2831. Gard. Press, St Louis, pp. 324328.

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