Genome Size, Cytotype Diversity and Reproductive Mode Variation of Cotoneaster integerrimus (Rosaceae) from the Balkans

Abstract

Cotoneaster integerrimus represents a multiploid and facultative apomictic system of widely distributed mountain populations. We used flow cytometry to determine genome size, ploidy level, and reproduction mode variation of the Balkan populations, supplemented by analysis of nuclear microsatellites in order to address: (i) geographic distribution and variation of cytotypes among the populations; (ii) variation of reproduction mode and the frequency of sexuality; (iii) pathways of endosperm formation among the sampled polyploids and their endosperm balance requirements; (iv) genotypic diversity and geographic distribution of clonal lineages of polyploids. The prevalence of apomictic tetraploid cytotype followed by sexual diploids and extremely rare triploids was demonstrated. This prevalence of tetraploids affected the populations’ structure composed from clonal genotypes with varying proportions. The co-occurrence of diploids and tetraploids generated higher cytotype, reproductive mode, and genotypic diversity, but mixed-ploidy sites were extremely rare. The endosperm imbalance facilitates the development and the occurrence of intermediate triploids in mixed-ploidy populations, but also different tetraploid lineages elsewhere with unbalanced endosperm. All these results showed that the South European populations of C. integerrimus have higher levels of cytotype and reproductive diversity compared to the Central European ones. Therefore, the South European populations can be considered as a potential reservoir of regional and global diversity for this species.

A Comparative Study of Morphology, Photosynthetic Physiology, and Proteome between Diploid and Tetraploid Watermelon (Citrullus lanatus L.)

“…Flow cytometry technology has been widely used for the detection of genome size and chromosome ploidy in horticultural plants [ 18 , 19 ]. Thus, to determine the polyploidy level of diploid and autotetraploid watermelon, we employed flow cytometry to detect the DNA content in our materials.…”

Reproduction Modes and Conservation Implications in Three Polyploid Sorbus Stenoendemics in Eastern Slovakia (Central Europe)

“…The question of the biological role of one-sperm- vs. two-sperm-fertilization of central cells has been debated. The genus Sorbus belongs to the subtribe Malinae Reveal within Rosaceae that includes other genera whose reproduction modes are similar to those of Sorbus [ 39 , 46 , 47 , 48 , 49 ]. The predominance of two sperm cells over one sperm cell in the fertilization of the central cell is typical in Amelanchier Medik.…”

“…In contrast, the one-sperm fertilization of the central cell is more frequent in Cotoneaster Medik. [ 48 , 49 ]. For Crataegus L. species, both alternatives were predominant in different species [ 39 , 46 , 50 ].…”

Genetic Variability in Balkan Paleoendemic Resurrection Plants Ramonda serbica and R. nathaliae Across Their Range and in the Zone of Sympatry

“…Several geological, climatic, and biogeographical factors have been identified that have contributed to the richness and endemism of the flora of this region ( Hewitt, 1996 , 1999 ; Stevanović et al, 1999 , 2007 ; Krstić et al, 2012 ; Kougioumoutzis et al, 2021 ). Polyploidization and interspecific hybridization have played an important role especially in the evolution of many plant taxa in the Balkan Peninsula, e.g., Alyssum ( Španiel et al, 2017 ), Cardamine ( Šlenker et al, 2021 ), Centaurium ( Banjanac et al, 2017 ), Cerastium ( Niketić et al, 2013 , 2021 ), Cotoneaster ( Bogunić et al, 2021 ), Edraianthus ( Lakušić et al, 2009 ), Knautia ( Frajman et al, 2015 ), Luzula ( Bačič et al, 2016 ), Sesleria ( Kuzmanović et al, 2013 ; Lazarević et al, 2015 ), Sorbus ( Hajrudinović et al, 2015 ), Veronica ( Padilla-García et al, 2018 ).…”