Chamomiles (Anthemis, Matricaria, Tanacetum) are of the genus Choseni or Citrus (Compositae) whose species are precious to medicinal herbs and are distributed in different regions of Iran. In this study, the shape and structure of chromosomes by microscopic observation and using specific staining methods, was performed on 21 populations belonging to three genera of Anthemis, Matricaria and Tanacetum, collected from different parts of Iran. For this purpose, the seeds were first cultured on petri dish and transferred to 25 ° C after sterilization. After germination, the roots were pretreated with 1% Alphabromonphthalene and then fixed with Luttski solution. NaOH was used for normal hydrolysis and to stain the Sthhmothoxylin. Microscopic specimens were prepared by squash method and then studied using an optical microscope BX41 Olympus with a magnification of 1750 ×. In all samples, the chromosome base number was x = 9 and the ploidy level (diploid) = 18 = n2 = x2. In all populations, metacentric chromosomes were predominant, and in addition to metacentric Sub Metacenter and Subtwostrater chromosomes, were observed as well.

Chromosomal patterns of experimental animals are useful tools for cytogenetics research and animal breeding. Chromosome investigations of the hairless guinea pig are rare, therefore, karyotype of hairless guinea pigs (twelve male and female) was studied using metaphase spreads of bone marrows and G banding techniques. The chromosomes diploid number was 2n=64 and polymorphism of three type chromosomal pairs were observed in the genus Cavia of Iranian hairless guinea pigs. A karyotype of 24 biarmed pairs and seven pairs of acrocentric chromosomes, 2 of sex chromosomes were also seen. The findings describe the karyology of the hairless guinea pig that is produced by Razi vaccine and serum research institute of Iran that improves our knowledge about laboratory hairless guinea pig and provides basic data for further use of the animal.

Eighteen species of Poa grow in Iran. Several introduced species of Poa are economically important. The species are commonly cultivated for lawns and pasture, and are a major forage species. In addition, they are widely planted for soil stablization and forage. Cytogenetic studies are very important for the aim of genetic improvement. Therefore, quantifying interspecies chromosome variation can provide important information for plant breeders. In order to study cytogenetic characteristics of Poa L., karyotypes of 4 species were analyzed using image analysis system. The basic chromosome number was x=7 for all of the studied species. But their ploidy levels varied indicating chromosome variation among the studied species. Variance analysis showed significant differences (P<1%) among the species for all of the recorded traits indicating chromosome measures variation in the studied germplasm. According to Levan method on chromosome type, all of the studied species had submetacentric chromosomes (Sm) that implies asymmetric karyotype for the species. Based on Pearson correlation method long arm length, short arm length and total chromosome length were inter-correlated (P<1%). CI had negative correlation with AR (P<1%) and number of chromosomes correlated with long arm length, short arm length and total chromosome length. LSD test showed significant differences (P<5%) on long arm length and total length in Poa strilis and Poa pratensis, for long arm, short arm and total length between Poa strilis and Poa angustifolia and for short arm length between Poa araratica and Poa angustifolia.

To evaluate the karyotype and genome size of Ae. triuncialis of Iran, 209 accessions from the collection of National Plant Gene Bank of Iran were studied by means of flow cytometry and cytogenetic traits. Accessions were analyzed by flow cytometry using DAPI method. The flow cytometry peak for Aegilops samples were in the range of 42 to 95 with average of 63.74 and standard deviation was 11.83.The average Peaks for control sample of hexaploid wheat was 120.67 with standard deviation 5.40. The mean ratio of sample peaks to check peaks for all samples was 0.44 -0.57 with average of 0.53. Karyotype studies showed that all aegilops accessions were tertaploied and number of their genome was x=7. Karyotype of Ae. triuncialis was include 5-10 pair sub metacentric and 4-9 metacentric chromosomes, classified according to Levan et al. (1964). Two Pairs satellite observed on short arms of chromosome number 8 and 12. The average of tallest chromosomes in accessions was 14.87 and average of shortest was 12.12 micrometer. Ratio of long to short arms observed from 1.66-2.03 and centromer indices from 0.35 to 0.39. So, Ae. triunciallis is in A2 according to Stebins table. Total form percentage (TF %) observed from 34.63 to 38.76. So, these characteristics show a relative symmetry for chromosomes of Ae. triuncialis and suggested that this species is in early steps of its evolutions.

Today, Karyotying studies are important to understand the genetic structure of animals. In the current research to evaluate the chromosomal structure of some Iranian native dogs, blood samples were collected from the Kurdi, Sarabi and samples of Alborz province. Blood samples were cultured in defined medium for 72 h at 37oС. Then the cell divisions were stopped at metaphase stage and chromosomal specimens were prepared for karyotype analysis. Next, centromeric index, total length of chromosome, chromosomal arm ratios and relative length of chromosomes were analyzed and the ideograms were created. The results indicated that the dog genomes contain 78 chromosomes including 38 acrocentric pairs in each sex, a pair of metacentric X in males and females and one metacentric Y chromosome in males. The average relative length of the autosomal chromosomes ranges from 1.13 to 4.89 mm in males and 1.10 to 5.21 mm in females. The ANOVA of the chromosomal data indicated that significant (P£0.05) differences in chromosomal parameters were observed in animals. The results indicate a bias of chromosome asymmetry in animals which could be related to evolutions of the canine chromosomal structures.

The karyotypes of 10 species (15 accessions) of Allium from Iran were investigated using the squash technique and 1% (w/v) aceto-iron-hematoxylin stain. The basic chromosome number was x = 8, and only in A. giganteum (1) x = 7. Karyotypes of 14 taxa of Allium were diploid with 2n = 16; only A. macrochaetum was tetraploid with 2n = 32. Satellite chromosomes were seen in A. asarense. All karyotypes were symmetrical, consisting of metacentric and submetacentric chromosome pairs. Only A. caspium and A. stipitatum (1) had subtelocentric chromosomes. Karyotype analysis according to Stebbins categories placed the studied taxa in symmetric classes of 1A and 2A, indicating a symmetric karyotype. The results of the analysis of variance showed significant differences for total chromosome length (TCL), mean chromosome length (CL), long arm length (LA), short arm length (SA) and intrachromosomal asymmetry index (A1). The longest chromosome length was detected on A. asarense, A. elburzense, A. giganteum (3), A. rotundum and A. stipitatum (3) (17. 9-19. 7 μ m), while A. ampeloperasum demonstrated the shortest value (8. 2 μ m). Results of cluster analysis based on chromosomal parameters classified the taxa into four groups using the unweighted pair group method with arithmetic mean (UPGMA). Using principal component analysis, the first three components determined 97. 3% of the total variation. The grouping of the taxa based on the 2-D scatter plot using the first two principal components, corresponding to the results of the karyotypic characteristics.

Somatic chromosome numbers and karyotypes of five populations of Nerium oleander in Iran were determined. karyological studies showed that, all the studied populations were diploid (2n = 2x = 22). The present study is the first report of the karyotype characteristics of N. oleander. The highest values of mean chromosome length (1. 45 μ m) and haploid chromosome length (15. 9 μ m) were found in the Chabahar population. The general shape of the karyotypes, indicated symmetry for all populations, as all chromosomes were metacentric type. According to Stebbin’ s classification (1971), populations fall in class 1A, thus indicating occurrence of chromosome symmetry among the populations. In addition, a detailed account of karyomorphology and estimates of asymmetry indices showed that, all of the populations were symmetric, among which Khash and Kuhdasht populations were considered as the most asymmetrical and symmetrical karyotypes, respectively. Based on karyotypic parameters, the considered populations were categorized into two groups viz. Chabahar, Fanuj, and Khash populations which were previously reported as N. indicum in Flora Iranica, separated from Karaj and Kuhdasht populations.