Caryologia. International Journal of Cytology, Cytosystematics and Cytogenetics 75(2): 101-108, 2022 Firenze University Press www.fupress.com/caryologia ISSN 0008-7114 (print) | ISSN 2165-5391 (online) | DOI: 10.36253/caryologia-1432 Caryologia International Journal of Cytology, Cytosystematics and Cytogenetics Citation: Isara Patawang, Suphat Pra- sopsin, Chatmongkon Suwannapoom, Alongklod Tanomtong, Puntivar Keaw- mad, Weera Thongnetr (2022) Chromo- somal description of three Dixonius (Squamata, Gekkonidae) from Thai- land. Caryologia 75(2): 101-108. doi: 10.36253/caryologia-1432 Received: October 22, 2021 Accepted: October 22, 2021 Published: September 21, 2022 Copyright: © 2022 Isara Patawang, Suphat Prasopsin, Chatmongkon Suwannapoom, Alongklod Tanomtong, Puntivar Keawmad, Weera Thongnetr. This is an open access, peer-reviewed article published by Firenze University Press (http://www.fupress.com/caryo- logia) and distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All rel- evant data are within the paper and its Supporting Information files. Competing Interests: The Author(s) declare(s) no conflict of interest. Chromosomal description of three Dixonius (Squamata, Gekkonidae) from Thailand Isara Patawang1, Suphat Prasopsin2, Chatmongkon Suwannapoom3, Alongklod Tanomtong4, Puntivar Keawmad5, Weera Thongnetr6,* 1 Department of Biology, Faculty of Science, Chiang Mai University, Muang Chiang Mai, Chiang Mai, Thailand 2 Research Academic Supports Division, Mahidol University, Kanchanaburi Campus, Sai- yok, Kanchanaburi, Thailand 3 Department of Fishery, School of Agriculture and Natural Resources, University of Phayao, Muang Phayao, Phayao, Thailand 4 Program of Biology, Faculty of Science, Khon Kaen University, Muang Khon Kaen, Khon Kaen, Thailand 5 Major of Biology, Faculty of Science and Technology, Mahasarakham Rajabhat Univer- sity, Muang Mahasarakham, Maha Sarakham, Thailand 6 Walai Rukhavej Botanical Research Institute, Mahasarakham University, Kantharawi- chai, Maha Sarakham, Thailand *Corresponding author: weeraatah@hotmail.com Abstract. Chromosomal characteristics and karyological analysis of three Dixonius, including D. hangseesom, D. siamensis and D. melanostictus, from Thailand were stud- ied. Chromosome preparations were conducted by squash technique from bone mar- row and testis. Conventional Giemsa’s staining and Ag-NOR banding techniques were applied to stain the chromosome. The results showed that the diploid chromosomes are 2n=40, for D. hangseesom and D. siamensis; and 2n=42, for D. melanostictus. The fun- damental number (NF) is 42 in D. hangseesom and D. siamensis and 44 in D. melanos- tictus. The types of chromosomes were 2 metacentrics and 38 telocentrics for D. hang- seesom and D. siamensis, while the karyotype of D. melanostictus comprised 2 acrocen- trics and 40 telocentrics. In the D. hangseesom and D. siamensis, NORs are located to the near centromere on long arm of the telocentric chromosome pair 13. Although, the NORs of D. melanostictus are situated on the subtelomeric region of telocentric chro- mosome pair 8. There are no sex differences in karyotypes between males and females of these three geckos species. We found that during metaphase I and metaphase II on male meiosis of the D. hangseesom and D. siamensis, the homologous chromosomes showed synapsis of 20 bivalents and 20 haploid chromosomes (n=20). Moreover, meta- phase I and metaphase II of the male D. melanostictus showed synapsis of 21 bivalents and 21 haploid chromosomes (n=21). Their karyotype formulas is as follows: D. hang- seesom (2n=40): Lm2 + Lt2 + Mt4 + St32, D. siamensis (2n=40): Lm2 + Lt6 + Mt4 + St28, and D. melanostictus (2n=42): La2 + Lt12 + Mt4 + St24. Keywords: Dixonius, chromosome, karyotype, Nucleolar Organizer Region (NOR). 102 Isara Patawang et al. INTRODUCTION Dixonius is a genus of Asian geckos or commonly known as leaf-toed geckos that belong to the class Rep- tilia, order Squamata, and family Gekkonidae. The Dixo- nius was first chosen to accommodate Southeast Asian leaf-toed geckos previously to the polyphyletic and near- ly cosmopolitan Phyllodactylus (Bauer et al. 1997). The D. siamensis is the type species of the genus Dixonius, which receive name from the first zoologist that note siamensis (Dixon 1964). In Thailand, total 7 species of Dixonius were found including D. dulayaphitakorum, D. hangseesom, D. kaweesaki, D. mekongensis, D. melanos- tictus, D. pawangkhananti and D. siamensis (Sumontha et al. 2017; Pauwels et al. 2020, 2021). Only about 10% of gekkonid species have been karyotyped and were studied with classical cytogenetic methods, including routine staining, as well as R, NOR and C banding (Moritz 1984; Shibaike et al. 2009). The series from 2n=28 to 46 of the diploid chromosomes is characteristic of the gekkonid lizard’s karyotype (Gor- man 1973; King 1987; Schmid et al. 1994). The typical karyotype consists of a gradual series of mono-armed chromosome (sometimes with a few bi-armed chromo- some), and there is no distinction between macro- and microchromosomes are present, the centromere is often subterminal (Gorman 1973). Karyotype evolution within the group is accompanied by Robertsonian fusions, fis- sions and pericentric inversions (Gorman 1973; King 1987). Examples of the gekkonid’s chromosome study in Thailand that were reported: Gekko gecko, 2n=38=12bi- armed+26mono-armed (Patawang et al. 2014); Hemi- dactylus frenatus, 2n=40=34bi-armed+6mono-armed; H. platyurus, 2n=46=2bi-armed+44mono-armed (Pata- wang and Tanomtong 2015); Cyrtodactylus kunyai, 2n=40=12bi-armed+28mono-armed; C. interdigitalis, 2n=42=10bi-armed+32mono-armed (Thongnetr et al. 2019); C. jarujini, 2n=40=28bi-armed+12mono-armed; and C. doisuthep, 2n=34=28bi-armed+6mono-armed (Thongnetr et al. 2021) etc. In Thailand, there is only one previous report on Dixonius species chromosome. Ota et al. (2001) dem- onstrated that D. siamensis’ karyotype by conventional staining technique is as 2n=42, male and female speci- men from Mae Yom National Park, Phrae Province, Thailand; and 2n=40, male from Phu Wua Wild Life Reserve Area, Nongkhai Province, Thailand. The present study of the karyological analysis of D. hangseesom, D. siamensis and D. melanostictus, provides the first report on the Ag-NOR banding technique, chromosome size, chromosome type, karyotype formula, and standardized idiogram which are compared to earlier reports. MATERIALS AND METHODS Sample collection Both male and female of three Dixonius species (Figure 1) were collected from three sites in Thailand, D. hangseesom from Kanchanaburi Province; D. siamensis from Chiang Mai Province; and D. melanostictus from Saraburi Province. The geckos were transferred to the laboratory and kept under standard conditions for one day prior to the experimentation. Chromosome preparation Chromosomes were directly prepared in vivo (Pata- wang et al. 2014) by injecting phy tohemagglutinin (PHA) solution into its abdominal muscle. After ten hours, colchicine is injected to animal intramuscular and its abdominal cavity and left for 8-10 hours. Bone marrow (in male and female) and testis (in male) are cut Figure 1. General characteristic of the D. hangseesom (a), D. siamensis (b) and D. melanostictus (c) from Thailand. Scale bars indicate 1 cen- timeter. 103Chromosomal description of three Dixonius (Squamata, Gekkonidae) from Thailand into small pieces then mix squash with 0.075M potas- sium chloride (KCl). After discarding all large cell piec- es, 15 ml of cell sediment is transferred to a centrifuge tube and incubated for 30-40 minutes. Cells were fixed in fresh cool Canoy fixative (3 absolute methyl alcohol: 1 glacial acetic acid) gradually added up to 8 ml before centrifuging again at 3,000 rpm for 10 minutes, where- upon the supernatant was discarded. Fixation was repeated until the supernatant was clear and the pellet was mixed with 1 ml fixative. The mixture was dropped onto a clean and cold slide by micropipette followed by the air-drying. Chromosome staining Conventional staining (Gosden 1994) The mixture is dropped onto a clean and cold slide by micropipette followed by the air-dry technique. The slide is conventionally stained with 20% Giemsa’s solu- tion for 30 minutes. Ag-NOR banding (Howell and Black 1980) The two drops of each 50% silver nitrate and 2% gelatin were added on slides, respectively. Then it was sealed with cover glasses and incubated at 60 °C for 5-10 minute. There after that it was soaked in distilled water until cover glasses are separated. Chromosome checking Ten clearly observable cells with well spread chro- mosomes of each male and female were selected and photographed. The length of short arm chromosome (Ls) and long arm chromosome (Ll) were measured and the length of total arm chromosome (LT, LT = Ls+Ll) was calculated. The relative length (RL), the centromeric index (CI), and standard deviation (SD) of RL and CI were estimated (Turpin and Lejeune 1965; Chaiyasut 1989). The CI (q/[p+q]) between 0.500-0.599, 0.600- 0.699, 0.700-0.899, and 0.900-1.000 were described as metacentric, submetacentric, acrocentric and telocentric chromosomes, respectively. The fundamental number (NF, number of chromosome arms) was obtained by assigning a value of 2 to the metacentric, submetacentric and acrocentric chromosomes and 1 to the telocentric chromosome. All data were used in karyotyping and idi- ograming. RESULTS AND DISCUSSION Diploid number and chromosome characteristics Karyomorphology of the D. hangseesom and D. sia- mensis revealed that the diploid chromosome number (2n) is 40 and the D. melanostictus showed 2n=42. The karyotypes of male and female D. hangseesom composed 2 large metacentrics, 2 large telocentrics, 4 medium telo- centrics and 32 small telocentrics (Table 1 and Figures 2a-b, 4a). For the karyotypes of male and female D. sia- mensis comprised 2 large metacentrics, 6 large telocen- trics, 4 medium telocentrics and 28 small telocentrics (Table 2 and Figures 2c-d, 4b). Though, both sexs of D. melanostictus’s karyotypes consisted 2 large acrocentrics, 12 large telocentrics, 4 medium telocentric and 24 small telocentrics (Table 3 and Figures 2e-f, 4c). All three Dix- onius species exhibit no sex differences in karyotypes between males and females (Figures 2a-f ). The chromo- somal characteristic of D. hangseesom and D. siamensis showed more the closed relationship than D. melanostic- tus. Karyotypes of the D. hangseesom and D. siamensis revealed the same of diploid number and chromosome type, which has only different chromosome size. Their karyotype formulas is as follows: 2n=40=Lm2 + Lt2 + Mt4 + St32 (D. hangseesom) 2n=40=Lm2 + Lt6 + Mt4 + St28 (D. siamensis) 2n=42=La2 + Lt12 + Mt4 + St24 (D. melanostictus). The chromosome character of D. hangseesom (2n=40) and D. melanostictus (2n=42) from this study is the first report of both species. However, the dip- loid result of D. siamensis (2n=40) in this report both showed difference and accordance with D. siamensis in the reported of Ota et al. (2001). It is possible that reported by Ota et al. (2001) may have studied more than one with the complex species. However, overall of these karyotypes of D. hangseesom, D. siamensis and D. melanostictus resemble to other gekkonid, which com- prised many gradient mono-armed (telocentric) and few bi-armed chromosomes (meta-, submeta- or acrocentric). Proximity of chromosome number and karyotype fea- ture within genus Dixonius represents a close evolution- ary line in the group. Nucleolar organizer regions and haploid number This study is the first report of nucleolar organizer regions in D. hangseesom, D. siamensis and D. melanos- tictus. In both sexs of the D. hangseesom and D. siamen- sis, we found the clearly observable NORs on the region 104 Isara Patawang et al. adjacent to subcentromeric of the telocentric chromosome pair 13th (Figures 3a-d, 4a-b). Whereas, the NORs of male and female D. melanostictus are situated on the subtelo- meric region of telocentric chromosome pair 8th (Figures 3e-f, 4c). The NORs characteristic of D. hangseesom and D. siamensis showed more the closed relationship than D. melanostictus. Position of nucleolar organizer regions of the D. hangseesom and D. siamensis revealed the same located, subcentromeric of telocentric chromosome pair 13th. Compared with other geckos, most showed two NORs appearing near terminal region (centromere or tel- omere) of small bi-armed or small mono-armed chromo- some. An example of the previous reports of the geckos’ NOR localization included in the genus Cyrtodactylus (Thongnetr et al. 2019, 2021), Gehyra (King 1983), Gekko (Chen et al. 1986; Shibaike et al. 2009; Patawang et al. 2014), Hemidactylus (Patawang and Tanomtong 2015), and Lepidodactylus (Trifonov et al. 2015). These previous studies showed the NOR appearing near terminal region of one homologous small chromosome. The metaphase I (meiosis I, reductional division) was found which can be defined as the 20 bivalents for D. hangseesom (Figure 5a) and D. siamensis (Figure 5c), and 21 bivalents for D. melanostictus (Figure 5e). No metaphase I cells with partially paired bivalents, which are speculated to be male heteromorphic sex chromo- somes in these three Dixonius species. Moreover, haploid chromosome of n=20 in D. hangseesom (Figure 5b), n=20 in D. siamensis (Figure 5d) and n=21 in D. melanostic- tus (Figure 5f ) were found at metaphase II (meiosis II, equational division) of spermatid cells. For these results, behavior and number of chromosomes in metaphase I and metaphase II confirmed of each other’s accuracy and also verified the accuracy of diploid chromosome in somatic cells. An overview of Dixonius chromosomal feature and their chromosome evolution Gekkonid chromosome that has been reported in the past, most species show the gradient karyotype, which comprising of many mono-armed chromosomes and few bi-armed chromosomes. Present results of D. hangsee- som, D. siamensis and D. melanostictus agree with chro- mosomal evolution line hypothesis within the gekkonid group. The karyotype of these three Dixonius showed the gradient of major telocentric, while just comprised 2 bi-armed chromosomes. These features conform to the Table 1. Mean length of short arm chromosome (Ls), long arm chromosome (Ll), length of total chromosomes (LT), centromeric index (CI), relative length (RL) and standard deviation (SD) of CI and RL from 20 metaphases of male and female yellow-tailed leaf-toed gecko (Dixonius hangseesom) 2n=40. Chr pair Ls Ll LT CI±SD RL±SD Chr size Chr type 1 6.156 6.718 12.874 0.522±0.024 0.143±0.002 Large Metacentric 2 0.000 10.305 10.305 1.000±0.000 0.114±0.002 Large Telocentric 3 0.000 7.204 7.204 1.000±0.000 0.080±0.001 Medium Telocentric 4 0.000 6.470 6.470 1.000±0.000 0.072±0.003 Medium Telocentric 5 0.000 5.445 5.445 1.000±0.000 0.060±0.002 Small Telocentric 6 0.000 4.924 4.924 1.000±0.000 0.055±0.003 Small Telocentric 7 0.000 4.434 4.434 1.000±0.000 0.049±0.003 Small Telocentric 8 0.000 4.037 4.037 1.000±0.000 0.045±0.003 Small Telocentric 9 0.000 3.661 3.661 1.000±0.000 0.040±0.001 Small Telocentric 10 0.000 3.484 3.484 1.000±0.000 0.039±0.002 Small Telocentric 11 0.000 3.297 3.297 1.000±0.000 0.037±0.002 Small Telocentric 12 0.000 3.036 3.050 1.000±0.000 0.034±0.001 Small Telocentric 13* 0.000 3.050 3.036 1.000±0.000 0.034±0.002 Small Telocentric 14 0.000 3.007 3.007 1.000±0.000 0.033±0.001 Small Telocentric 15 0.000 2.724 2.724 1.000±0.000 0.030±0.003 Small Telocentric 16 0.000 2.661 2.671 1.000±0.000 0.030±0.003 Small Telocentric 17 0.000 2.671 2.661 1.000±0.000 0.029±0.003 Small Telocentric 18 0.000 2.434 2.434 1.000±0.000 0.027±0.001 Small Telocentric 19 0.000 2.273 2.273 1.000±0.000 0.025±0.001 Small Telocentric 20 0.000 2.239 2.239 1.000±0.000 0.025±0.002 Small Telocentric Abbreviations: Chr, chromosome; *, NORs bearing chromosomes. 105Chromosomal description of three Dixonius (Squamata, Gekkonidae) from Thailand hypothesis of rearrangement from ancestral karyotype by Robertsonian fusions, fissions or pericentric inver- sions (Gorman 1973; King 1987). In this study, from all chromosome characters by conventional Giemsa’s stain- ing and Ag-NOR banding techniques, we suggest that the chromosome of Dixonius showed a high genetic con- servation and there were only a few changes at the chro- mosome structure level. However, the chromosome of D. hangseesom and D. siamensis showed more the closed evolutionary relationship than D. melanostictus. ACKNOWLEDGEMENTS This research was financially supported by shar- ing from the Thailand Science Research and Innovation (TSRI) 2021, Mahasarakham University and the Unit of Excellence 2022 on Biodiversity and Natural Resources Management, University of Phayao (FF65-UoE003). The project was approved by the Institute of Animals for Scientific Purpose Development of National Research Council of Thailand (Resolution U1-02740-2559). Figure 2. Metaphase chromosome plates and karyotypes using con- ventional Giemsa’s staining of male (a) and female (b) D. hangsee- som (2n=40); male (c) and female (d) D. siamensis (2n=40); and male (e) and female (f ) D. melanostictus (2n=42). Scale bars indi- cate 10 micrometers. Figure 3. Metaphase chromosome plates and karyotypes using Ag- NOR staining of male (a) and female (b) D. hangseesom (2n=40); male (c) and female (d) D. siamensis (2n=40); and male (e) and female (f ) D. melanostictus (2n=42). Arrows indicate nucleolar organizer regions (NORs) and scale bars indicate 10 micrometers. 106 Isara Patawang et al. Table 2. Mean length of short arm chromosome (Ls), long arm chromosome (Ll), length of total chromosomes (LT), centromeric index (CI), relative length (RL) and standard deviation (SD) of CI and RL from 20 metaphases of male and female Siamese leaf-toed gecko (Dixo- nius siamensis), 2n=40. Chr pair Ls Ll LT CI±SD RL±SD Chr size Chr type 1 5.925 6.102 12.027 0.507±0.032 0.125±0.002 Large Metacentric 2 0.000 10.928 10.928 1.000±0.000 0.113±0.001 Large Telocentric 3 0.000 8.012 8.012 1.000±0.000 0.083±0.002 Large Telocentric 4 0.000 7.072 7.072 1.000±0.000 0.073±0.003 Large Telocentric 5 0.000 6.821 6.821 1.000±0.000 0.071±0.003 Medium Telocentric 6 0.000 6.121 6.121 1.000±0.000 0.064±0.002 Medium Telocentric 7 0.000 5.814 5.814 1.000±0.000 0.060±0.002 Small Telocentric 8 0.000 5.214 5.214 1.000±0.000 0.054±0.001 Small Telocentric 9 0.000 4.012 4.012 1.000±0.000 0.042±0.002 Small Telocentric 10 0.000 3.628 3.628 1.000±0.000 0.038±0.003 Small Telocentric 11 0.000 3.421 3.421 1.000±0.000 0.036±0.002 Small Telocentric 12 0.000 3.214 3.214 1.000±0.000 0.033±0.001 Small Telocentric 13* 0.000 3.042 3.042 1.000±0.000 0.032±0.001 Small Telocentric 14 0.000 2.988 2.988 1.000±0.000 0.031±0.002 Small Telocentric 15 0.000 2.756 2.756 1.000±0.000 0.029±0.003 Small Telocentric 16 0.000 2.524 2.524 1.000±0.000 0.026±0.003 Small Telocentric 17 0.000 2.326 2.326 1.000±0.000 0.024±0.001 Small Telocentric 18 0.000 2.214 2.214 1.000±0.000 0.023±0.001 Small Telocentric 19 0.000 2.112 2.112 1.000±0.000 0.022±0.002 Small Telocentric 20 0.000 2.042 2.042 1.000±0.000 0.021±0.002 Small Telocentric Abbreviations: Chr, chromosome; *, NORs bearing chromosomes. Table 3. Mean length of short arm chromosome (Ls), long arm chromosome (Ll), length of total chromosomes (LT), centromeric index (CI), relative length (RL) and standard deviation (SD) of CI and RL from 20 metaphases of male and female dark-sides ground gecko (Dix- onius melanostictus), 2n=42. Chr pair Ls Ll LT CI±SD RL±SD Chr size Chr type 1 2.019 5.945 7.964 0.746±0.029 0.101±0.002 Large Acrocentric 2 0.000 7.363 7.363 1.000±0.000 0.094±0.002 Large Telocentric 3 0.000 7.241 7.241 1.000±0.000 0.092±0.001 Large Telocentric 4 0.000 7.026 7.026 1.000±0.000 0.089±0.003 Large Telocentric 5 0.000 6.736 6.736 1.000±0.000 0.086±0.003 Large Telocentric 6 0.000 6.159 6.159 1.000±0.000 0.078±0.002 Large Telocentric 7 0.000 4.739 4.739 1.000±0.000 0.060±0.002 Large Telocentric 8* 0.000 4.506 4.506 1.000±0.000 0.057±0.001 Medium Telocentric 9 0.000 4.102 4.102 1.000±0.000 0.052±0.003 Medium Telocentric 10 0.000 3.824 3.824 1.000±0.000 0.049±0.002 Small Telocentric 11 0.000 3.256 3.256 1.000±0.000 0.041±0.003 Small Telocentric 12 0.000 2.109 2.109 1.000±0.000 0.027±0.003 Small Telocentric 13 0.000 2.047 2.047 1.000±0.000 0.026±0.001 Small Telocentric 14 0.000 2.024 2.024 1.000±0.000 0.026±0.001 Small Telocentric 15 0.000 1.812 1.812 1.000±0.000 0.023±0.001 Small Telocentric 16 0.000 1.556 1.556 1.000±0.000 0.020±0.002 Small Telocentric 17 0.000 1.508 1.508 1.000±0.000 0.019±0.003 Small Telocentric 18 0.000 1.375 1.375 1.000±0.000 0.017±0.002 Small Telocentric 19 0.000 1.130 1.130 1.000±0.000 0.014±0.002 Small Telocentric 20 0.000 1.062 1.062 1.000±0.000 0.014±0.002 Small Telocentric 21 0.000 1.057 1.057 1.000±0.000 0.013±0.001 Small Telocentric Abbreviations: Chr, chromosome; *, NORs bearing chromosome. 107Chromosomal description of three Dixonius (Squamata, Gekkonidae) from Thailand REFERENCES Bauer AM, Good DA, Branch WR. 1997. 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Respective bivalent on metaphase I and haploid chromo- some on metaphase II of male D. hangseesom (20 bivalents, a; 20 haploid chromosomes, b), male D. siamensis (20 bivalents, c; 20 haploid chromosomes, d) and male D. melanostictus (21 bivalents, e; 21 haploid chromosomes, f ). Scale bars indicate 5 micrometers. Caryologia International Journal of Cytology, Cytosystematics and Cytogenetics Volume 75, Issue 2 - 2022 Firenze University Press Cytogenetic Studies of Six Species in Family Araceae from Thailand Piyaporn Saensouk1, Surapon Saensouk2,*, Rattanavalee Senavongse2 Effect of Ag Nanoparticles on Morphological and Physio-biochemical Traits of the Medicinal Plant Stevia Rebaudiana Sherzad R. Abdull, Sahar H. Rashid*, Bakhtiar S. Ghafoor, Barzan S. Khdhir Morphometric analysis and genetic diversity in Hypericum L. using sequence related amplified polymorphism Wei Cao1, Xiao Chen2,*, Zhiwei Cao3 Population Differentiation and Gene Flow of Salicornia persica Akhani (Chenopodiaceae) Xiaoju Zhang1, Li Bai2,*, Somayeh Esfandani-Bozchaloyi3 SCoT molecular markers are efficient in genetic fingerprinting of pomegranate (Punica granatum L.) cultivars Shiva Shahsavari1, Zahra Noormohammadi1,*, Masoud Sheidai2,*, Farah Farahani3, Mohammad Reza Vazifeshenas4 First record of nucleus migration in premeiotic antherial cells of Saccharum spontaneum L. (Poaceae) Chandra Bhanu Singh1, Vijay Kumar Singhal2, Manish Kapoor2,* Genetic Characterization of Salicornia persica Akhani (Chenopodiaceae) Assessed Using Random Amplified Polymorphic DNA Zhu Lin1,*, Hamed Khodayari2 Comparative chromosome mapping of repetitive DNA in four minnow fishes (Cyprinidae, Cypriniformes) Surachest Aiumsumang1, Patcharaporn Chaiyasan2, Kan Khoomsab3, Weerayuth Supiwong4, Alongklod Tanomtong2 Sumalee Phimphan1,* Classical chromosome features and microsatellites repeat in Gekko petricolus (Reptilia, Gekkonidae) from Thailand Weera Thongnetr1, Surachest Aiumsumang2, Alongklod Tanomtong3, Sumalee Phimphan2,* Genotoxic and antigenotoxic potential of encapsulated Enhalus acoroides (L. f.) Royle leaves extract against nickel nitrate Made Pharmawati1,*, Ni Nyoman Wirasiti1, Luh Putu Wrasiati2 Chromosomal description of three Dixonius (Squamata, Gekkonidae) from Thailand Isara Patawang1, Suphat Prasopsin2, Chatmongkon Suwannapoom3, Alongklod Tanomtong4, Puntivar Keawmad5, Weera Thongnetr6,* First Report on Classical and Molecular Cytogenetics of Doi Inthanon Bent-toed Gecko, Cyrtodactylus inthanon Kunya et al., 2015 (Squamata: Gekkonidae) in Thailand Suphat Prasopsin1, Nawarat Muanglen2, Sukhonthip Ditcharoen3, Chatmongkon Suwannapoom4, Alongklod Tanomtong5, Weera Thongnetr6,* Evaluation of genetic diversity and Gene-Pool of Pistacia khinjuk Stocks Based On Retrotransposon-Based Markers Qin Zhao1,*, Zitong Guo1, Minxing Gao1, Wenbo Wang1, Lingling Dou1, Sahar H. Rashid2 A statistical overview to the chromosome characteristics of some Centaurea L. taxa distributed in the Eastern Anatolia (Turkey) Mikail Açar1,*, Neslihan Taşar2 Cytotoxicity of Sunset Yellow and Brilliant Blue food dyes in a plant test system Elena Bonciu1, Mirela Paraschivu1,*, Nicoleta Anca Șuțan2, Aurel Liviu Olaru1