A Cytogenetic, Morphological, and Ecological Comparison of Seven Different Species of Achillea.ssp. Accessions in Kurdistan Province, Iran

Abstract

We conducted the present study on seven important medicinal species of Achillea (4 replications per species) (in a total of 28 samples) in their natural habitats in two consecutive years (2018, 2019) in terms of morphological, cytogenetic, and ecological aspects. This study aimed to examine the environmental variables affecting the morphology, cytogenetics, and evolution of the plant. The results indicated that the populations had a Ploidy base number (x= 9) and the diploid, tetraploid, and hexaploid levels were observed. In addition to the inter-species diversity, there was the intra-species genetic diversity as (4x, 6x) Ac. millefolium (2x, 4x), Ac.vermicularis (2x, 4x), Ac. tenuifolia (2x, 4x), Ac. Alppica(2x) , Ac.talagonica(2x),Ac. biebersteinii, and Ac.wilhelmsii (4x). Further studies also indicated that 11 out of 28 populations had 1A symmetry, 15 populations had 2B symmetry, a population had 2A, and another population had 2B. Principal component analysis (PCA) of cytogenetic variables could not differentiate the species well probably due to the superiority of intra-species diversity of populations to inter-species diversity. Therefore, it seems that the evolution and speciation of this genus are mostly due to the increase or decrease in the amount of chromatin and chromosome length. The examination of principal component analysis in environmental indices also showed that Ac. millefolium hexaploid species was more adapted to the environment with higher percentages of clay and silt while the Ac.tenuifolia tetraploid species preferred a sandy habitat over other environmental factors. Furthermore, Ac.vermicularis tetraploid species indicated the greatest sensitivity to altitude. However, the Ac.biebersteinii tetraploid species reacted to meteorological parameters, such as perception rate and minimum temperature.