The evolution of chromosome number and ribosomal DNA (rDNA) loci number and localisation were studied in Onobrychis Mill. Diploid and tetraploid species, as well as two basic chromosome numbers, x = 7 and x = 8, were observed among analysed taxa. The chromosomal distribution of rDNA loci was presented here for the first time using fluorescence in situ hybridisation (FISH) with 5S and 35S rDNA probes. Onobrychis species showed a high polymorphism in the number and localisation of rDNA loci among diploids, whereas the rDNA loci pattern was very similar in polyploids. Phylogenetic relationships among the species, inferred from nrITS sequences, were used as a framework to reconstruct the patterns of basic chromosome number and rDNA loci evolution. Analysis of the evolution of the basic chromosome numbers allowed the inference of x = 8 as the ancestral number and the descending dysploidy and polyploidisation as the major mechanisms of the chromosome number evolution. Analyses of chromosomal patterns of rRNA gene loci in a phylogenetic context resulted in the reconstruction of one locus of 5S rDNA and one locus of 35S rDNA in the interstitial chromosomal position as the ancestral state in this genus.

With an annual global production of approximately 25 million tons, the common bean (Phaseolus vulgaris L), a member of the genus Phaseolus, is one of the major protein sources used as food for humans. In this study, it was aimed to investigate the genome size of the common bean genetic resource collection (154 common bean accessions) in Turkey by flow cytometry (FCM) and determine whether geographical variables affected the genome size. In addition, the number and distribution of 5S and 45S ribosomal DNA loci were designated by performing a fluorescence in situ hybridization (FISH) analysis in some of the accessions. The FCM analyses revealed that the mean nuclear DNA content of the accessions varied from 1.28 pg2C-1 to 1.55 pg2C-1 (mean 1.35 pg2C-1), and the differences between these accessions were statistically significant (P < 0.01). Intraspecific variation in the genome size was determined, and a positive correlation was found between the altitude and genome size. However, latitude and longitude did not have any statistically significant effect on the genome size. In the principal coordinate analysis, the accessions were divided into 3groups. Based on the results of the FISH analysis performed on 5 different accessions with varying genome sizes, using 5S and 45S rDNA genes as probes, the number of 5S rDNA loci was 4 in the common bean and stable among the common bean accessions, while the number of 45S rDNA loci was highly polymorphic, varying between 6 and 16. Consequently, it was determined in the present study that the genetic resource collection of common bean had a wide variation in terms of genome size and genome organization.

Karyotypes in 16 representative taxa of the Ophrys genus are compared, based on Feulgen-stained somatic metaphase chromosomes. The karyotypes of O. omegaifera subsp. israelitica, O. ulupinara, O. lycia, O. argolica subsp. lucis, O. argolica subsp. lesbis, O. climacis and O. reinholdii subsp. reinholdii are described for the first time. Karyological analyses indicate relationships among the species with respect to their asymmetry indices. All Ophrys taxa studied were diploid with 2n = 2x = 36 chromosomes. One B chromosome has been detected among the chromosomes of O. argolica subsp. lucis. All karyotypes are symmetrical, consisting of metacentric and submetacentric chromosomes. The longest chromosomes of all the investigated specimens contain a secondary constriction. It is determined that there is a correlation between the total number of chromosomes having secondary constrictions and the evolutionary development order of the taxa. Based on nuclear DNA content, analysis was carried out by flow cytometer using propodium iodide as fluorochrome, 2C nuclear DNA content of 16 Ophrys species varying between 20.80 pg (O. argolica subsp. lucis) and 23.11 pg (O. omegaifera subsp. israelitica). Karyotype asymmetry relationships are discussed according to the bidimensional scatter plots of A₁–A₂, CV_CL–CV_CI, CV_CL–M_CA and CV_CI–M_CA.

Bu çalışmada, flow sitometri analizi ile in vitro yetiştirilmiş A. caricum bitkilerinin çekirdek DNA içeriğinin belirlenmesi, ayrıca in vitro çoğaltılan bitkilerin genetik stabilitelerinin değerlendirilmesi amaçlanmıştır. Bitkinin tohumları, 3% sukroz ve 0.7% fitoagar içeren Murashige ve Skoog besin ortamında çimlendirilmiştir. Çimlenen fideler kontrollü bir ortamda in vitro olarak büyütülmüştür. In vitro çoğaltım için nodal eksplantlar üç farklı sürgün indüksiyon ortamında 3-4 hafta kültüre alınmıştır. Adventif sürgünler sürgün indüksiyon ortamı ile aynı formülasyonlara sahip MS besin ortamına çoğaltılmaları için aktarılmıştır. Çoğaltılan adventif sürgünler, daha sonra bitki büyüme düzenleyicileri içermeyen MS ortamına aktarılmıştır. In vitro yetiştirilen bitkiler ve in vitro çoğaltılan bitkiler flow sitometri ile analiz edilmiştir. Yapılan flow sitometri analizleri, in vitro yetiştirilen bitkilerin 1.75 pg/2C±0.01 DNA içeriğine sahip olduğunu göstermiştir. Sonuçlar, çoğaltılan bitkilerin tohumdan çimlenen bitkiler ile benzer DNA içeriğine sahip olduğunu göstermiştir. Bu sonuçlar, analiz edilen bireylerin genetik olarak stabil olduğunu önermektedir. Bununla birlikte, A. caricum hakkında daha kapsamlı bilgilere ulaşmak için ek çalışmalar gerekmektedir.

The aim of the study was to determine the chromosome number and nuclear DNA content of an endemic plant, V. scamandri, using 14-week-old plants germinated from seed and to determine the genetic stability based on flow cytometry analyses in callus tissue induced MS medium containing 1 mg/L Kin + 1 mg/L 2,4-D and 9-week-old propagated plants, induced and developed on MS medium containing 2 mg/L Kin + 0.1 mg/L 2,4-D. In the mitotic chromosome counts showed V. scamandri had 2n = 16. Flow cytometric analysis revealed that 14-week-old in vitro grown plants has 0.73 pg/2C ± 0.01, callus tissue has 0.76 pg/2C ± 0.02 and propagated plantlets has as 0.79 pg/2C ± 0.01. The results proved that propagated plants had similar DNA content to the seed-derived plants which showed analysed plants were genetically stable.