Determination of the Level of Variation in Polyploidy among Kentucky Bluegrass Cultivars by Means of Flow Cytometry

Abstract

search into the genetics of Kentucky bluegrass can be difficult because of a complex genome that can affect Kentucky bluegrass (Poa pratensis L.) is an important cool-season many different variables. For instance, genome size has grass species in the turfgrass and forage industries. Understanding the genetics of Kentucky bluegrass is useful in developing improved adaptive significance and influences phenotype by the cultivars and hybrids. However, studying the genetics of Kentucky expression of its genic content and by the physical effects bluegrass can often be difficult because of the high variation in ploidy of its mass and/or volume (Bennett and Leitch, 1995). In level that results from its facultative apomictic reproductive nature.angiosperms, DNA amount has been shown to correlate Flow cytometry provides an easy and accurate method for assessing with a wide range of important characters such as minithis variation by quantifying DNA content. The purpose of our study mum generation time and ecological behavior. Large was to determine the level of variation in ploidy in Kentucky bluegrass variations in ploidy level exist within and between cultiby analyzing its DNA content using flow cytometry. In addition, DNA vars because of the facultative apomictic nature of recontent was compared with genetic similarity derived from DNA production in Kentucky bluegrass. Therefore, it is not marker data, and was also correlated with chromosome number. possible to assign a specific ploidy level to Kentucky Twenty-two cultivars of Kentucky bluegrass were selected for the study by considering the range of variability in morphological traits bluegrass cultivars. The production of reduced and unand genetic distance derived from DNA marker data. We found that reduced eggs accounts for the differences in chromothe DNA content of Kentucky bluegrass genotypes from the 22 cultisome number. Research has demonstrated that the chrovars ranged from 5.39 to 17.69 pg of DNA/2C and that a majority of mosome number in Kentucky bluegrass can vary from the genotypes had a DNA content value in the range of 7 to 13 pg. 28 to 140, which corresponds to euploid chromosome A significant correlation between DNA content and chromosome numbers with x ϭ 7 (Lö ve and Lö ve, 1975; Barcaccia number was detected. Euploid chromosome numbers (x ϭ 7) with a et al., 1997). range from the pentaploid (2n ϭ 5x ϭ 35) to the quindecaploid (2n ϭ The ability to quickly estimate DNA amount would 15x ϭ 105) were found along with aneuploid numbers. The results facilitate Kentucky bluegrass research by allowing the of this research could aid both breeders and researchers in studying inclusion or exclusion of DNA amount as a variable in the genetics of the species and in improving Kentucky bluegrass cultivars via intra-and interspecific hybridizations.

Genomic aspects of research involving polyploid plants

“…Ploidy level in plants is often estimated by measuring the C-value (amount of DNA in the unreplicated gametic nucleus) using flow cytometry (Clarindo et al 2008;Dart et al 2004;Eaton et al 2004;Grundt et al 2005;Halverson et al 2008;Harbaugh 2008). The counting of chloroplast number in the epidermal guard cells of stomata can be used as an indirect ploidy indicator for the rapid screening of polyploids (Ewald et al 2009;Ho et al 1990).…”

Creation of Hexaploid and Octaploid Zoysiagrass Using Colchicine and Breeding

“…(Huff and Palazzo, 1998), bentgrass ( Agrostis spp.) (Bonos et al, 2002), and Kentucky bluegrass ( Poa pratensis L.) (Eaton et al, 2004) has been facilitated through screening germplasm with flow cytometry rather than using leaf, stem, and inflorescence measurements. On the opposite end of this spectrum, a large degree of variability for plant, root, and inflorescence morphology has been documented for members of the same species in bermudagrass (Harlan and de Wet, 1969) and zoysiagrass (Schwartz et al, 2010) with the same ploidy level.…”

Cool‐Season Forage Grasses

“…Its rhizomatous growth habit makes heavy grazing or frequent cutting are not as detrimental to its sod formation as they are for more upright species (Wedin and Huff, 1996). Kentucky bluegrass is used for grazing on >15 million hectares of pastures throughout the northeastern and north-central United States and substantial areas of Europe and Canada (Eaton et al, 2004).…”