Genetic Diversity Assessment of Iranian Kentucky Bluegrass Accessions: II. Nuclear DNA Content and Its Association with Morphological and Geographical Features

Poa pratensis L. is a perennial turfgrass with high regeneration and fertility, resistance to cold and drought, and quick colonization. By facultative apomixis, this plant can create a wide range of ploidy levels (2n = 22 to 2n = 154), resulting in a wide range of chromosomal numbers and sexual and apomictic reproductive diversity. The plant materials included fifty accessions from Iran's Center, South, North, North-East, North-West, and West ecoregions. UPOV standards were used to measure the qualities that were researched. The squash technique of chromosome counting revealed that Iranian Kentucky bluegrass accessions had chromosomal counts ranging from 24 to 87. The relative sizes of the 2C genomes were measured using laser flow cytometry. The range of DNA content was fairly wide, ranging from 4.92 to 11.52 pg. DNA content has a strong positive correlation with elevation, a moderately positive correlation with flag leaf length and leaf sheath width, and a negative correlation with inflorescence anthocyanin color and leaf anthocyanin color. The genotypes and ecological zones of this plant in Iran were distinguished based on morphological diversity and DNA content. The results from this study could be useful in identifying and studying wild Kentucky bluegrass genotypes. It aids in predicting the location of rare genotypes used as breeding materials. It can also increase the plant's variability for future generations by introducing new ecotypes, with particular genomic and morphological traits, to previously cultivated populations. We expect that the findings of this study will aid in understanding the evolution of this plant in the context of Iran's climatic variety.

Automated summary

This study analyzes the morphological characteristics and DNA content of Poa pratensis L. resources from different geographical regions in Iran, revealing the diversity of chromosomal numbers and sexual and apomictic reproduction in this plant. The findings are valuable for identifying and studying wild Kentucky bluegrass genotypes and understanding the plant's evolution in the context of Iran's climatic variety.