Hamideh Javadi
Abstract
Chromosome numbers in 19 populations of Tanacetum polycephalum and Tanacetum parthenium from natural resources gene bank, that collected from different regions of Iran, were determined for the first time. The samples prepared by using root tips. After pretreatment, fixation, hydrolysis and staining, ...
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Chromosome numbers in 19 populations of Tanacetum polycephalum and Tanacetum parthenium from natural resources gene bank, that collected from different regions of Iran, were determined for the first time. The samples prepared by using root tips. After pretreatment, fixation, hydrolysis and staining, the microscopic samples prepared by squash method, metaphases were captured using an optical microscope. The best metaphases plates were selected and used for karyotype analyses. In all of populations the basic chromosome number was x=9 and the populations showed two ploidy levels (diploid & tetraploid). The type of the most chromosomes in all of the populations was metacentric (m) and sub-metacentric (sm) and located in 2A and 2B except for T. parthenium (Yazd, Taft) with 5m+3sm+1st karyotype formula and 2C Stebbins classes. In addition, T. polycephalum (Esfahan, Golpayegan) with the highest value of AR and A1 had karyotype heterogeneity, also T. polycephalum (Esfahan, Golpayegan) and T. polycephalum (West-Azerbaijan, Uromeyeh) had the highest value of chromosome length (TL). Detailed karyotype allows us to group the different populations based on Stebbins classes and asymmetry indices.
Massoud Ranjbar; Samineh Nouri
Abstract
The biogeography of genus Linaria was revealed by the available chromosome counts from all over the world. Chromosome numbers of 92 taxa of the genus Linaria are included in an on-line karyological database. Furthermore, information about chromosome numbers taken from 374 literature sources was used ...
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The biogeography of genus Linaria was revealed by the available chromosome counts from all over the world. Chromosome numbers of 92 taxa of the genus Linaria are included in an on-line karyological database. Furthermore, information about chromosome numbers taken from 374 literature sources was used in this paper. Each database record includes name of taxon, data on chromosome and data on the origin of the material and species-area distribution. Each database also provides a reported chromosome number and place of publication. More than half of the available species in chromosome data are diploid or consist of both diploid and polyploid populations and a few numbers of the species are polyploid. For the first time, in this study, mitosis and meiosis chromosome numbers of 13 populations belonging to three species, namely L. lineolata Boiss (2n = 2x = 12), L. fastigiata Chav. (2n = 2x = 12) and L. dalmatica (L.) Mill. (2n = 2x = 12), were determined by examining anthers. In addition, pollen stainability has been documented in Linaria populations in Iran.
