Variability of Bluegrass (Poa) in Siberia

Siberian bluegrass (Poa) includes a number of polymorphic species such as P. arctica s.l., P. nemoralis s.l., P. palustris s.l., P. pratensis s.l., P. sibirica s.l., and P. smirnovii s.l., plus numerous hybrids and purported derivatives (e.g., P. attenuata s.l., P. glauca s.l., P. urssulensis s.l.). In Siberia Poa is represented by morphologically isolated species and hybrid-apomictic complexes, including both distinct species and taxonomic groups of obscure rank. Section Stenopoa is especially rich in these complexes. Most of the key morphological characters used in the taxonomy of bluegrass vary as much within populations as among populations and thus do not support recognition of some previously described taxa. It is likely that karyological or other genetic data would identify regionally distinct taxa. The area of the greatest intraspecific variation of Poa in Siberia is the Altai Mountain region based on analyses of distribution and morphology. Geography must be considered during conservation planning activities to avoid impacting locally adapted and morphologically divergent populations of broadly distributed species

The Challenge of a Siberian Bluegrass (Poa) Phylogeny

In Siberia, the bluegrass genus (Poa) comprises 43 species and 61 subspecies in 12 sections. Diverse modes of speciation, including polyploidy and hybridization, have led to reticulate evolution and adaptive radiation. Cladistic methods that ignore hybridization and reticulate evolution may not be appropriate for morphological data. The number of morphological characters suitable for bluegrass analysis is limited, a majority does not have clear adaptive significance, and the character states cannot be readily polarized, rendering phylogenetic reconstruction very difficult in this group. Other methods of estimating phylogenetic relationships should be used to test hypotheses about relationships and hybridization. Biochemical and molecular data, as well as karyological, phytogeographical, and other lines of evidence should be combined to establish an explicit and testable hypothesis of the sequence of character state changes acquired during biotic differentiation

Investigation of genetic structure in mesomorphic bluegrasses, Poa section Stenopoa dum, by using ISSR markers

A morphological and genetic analysis of five mesomorphic bluegrasses populations, Poa section Stenopoa, from a range of geographical locations were performed. We have established that all the populations have different level of the morphological and genetic diversity. A total of 79 DNA bands were obtained from six ISSR primers, including 61 polymorphic bands. Molecular data have shown no clear difference between morphologically homogeneous populations and hybrid populations P. palustris and P. nemoralis. This result may be due to the high genetic diversity of the populations studied

Polygonum schischkinii is a member of Atraphaxis (Polygonaceae, Polygoneae): evidences from morphological and molecular analyses

The Chinese endemic Polygonum schischkinii was studied from both morphological and molecular points of view. On the basis of the structure of ocreas and ocreolas, P. schischkinii appears to be a member of the genus Atraphaxis. The results of Maximum Likelihood and Bayesian analyses of combined data of the plastid [rpl32-trnL(UAG) IGS, trnL(UAA) intron, trnL-trnF IGS] and nuclear rDNA ITS1-2 regions, carried out on 61 members of tribe Polygoneae, confirmed position of P. schischkinii in the Atraphaxis clade. A new combination-Atraphaxis glareosa-based on P. glareosum, which has nomenclatural priority over P. schischkinii, is proposed. Ecological notes and a detailed distributional map of the species are also provided. © 2021 Magnolia Press. All rights reserved

Phytoliths from some grasses (Poaceae) in arid lands of Xinjiang, China

Opal phytoliths, as silicon dioxide inclusions, are abundant in different parts of a plant. It is known that grasses are the most representative in this respect. The research of phytoliths, removed from 25 most common grass species in the arid and semiarid lands of the Junggar Basin and adjacent areas, has been undertaken. The visual estimation of diversity and variability of silica cells and identification of their morphological types (patterns) were also the aim of our research. Since the work is preliminary, we have emphasized on the visual estimation of silica cell variability and involved only the leaf blades in the analysis. Drawings of the revealed silica cells, characteristic of 25 species, are provided. The sig-nificant morphological diversity of phytoliths has been revealed, as well as their taxonomic similarity at the level of subfamilies. These data can be used for the identification of phytoliths from sediments

Multiple founder events explain the genetic diversity and structure of the model allopolyploid grass Brachypodium hybridum in the Iberian Peninsula hotspot

Background and Aims It is accepted that contemporary allopolyploid species have originated recurrently, but very few cases have been documented using multiple natural formations of the same species. To extend our knowledge, we have investigated the multiple origins, genetic variation and structure of the allotetraploid grass Brachypodium hybridum with respect to its progenitor diploid species B. distachyon (D genome) and B. stacei (S genome). For this, our primary focus is the Iberian Peninsula, an evolutionary hotspot for the genus Brachypodium. Methods We analysed 342 B. hybridum individuals from 36 populations using ten nuclear SSR loci and two plastid loci. The B. hybridum genetic profiles were compared with those previously reported for B. stacei and B. distachyon. In addition, phylogenetic analysis of the plastid data was performed for a reduced subset of individuals. Key Results The nuclear simple sequence repeat (SSR) genetic analysis detected medium to high genetic diversity, with a strong south-to-north genetic structure cline, and a high selfing rate in B. hybridum. Comparative genetic analysis showed a close relatedness of current B. hybridum D allelic profiles with those of B. distachyon, but a lack of similarity with those of B. stacei, suggesting another B. stacei source for the B. hybridum S alleles. Plastid analysis detected three different bidirectional allopolyploidization events: two involved distinct B. distachyon-like ancestors and one involved a B. stacei-like ancestor. The south-eastern Iberian Peninsula B. hybridum populations were more genetically diverse and could have originated from at least two hybridization events whereas north-eastern/north-western Iberian Peninsula B. hybridum populations were less diverse and may have derived from at least one hybridization event. Conclusions The genetic and evolutionary evidence supports the plausible in situ origin of the south-eastern and northern Iberian Peninsula B. hybridum allopolyploids from their respective local B. distachyon and unknown B. stacei ancestors. The untapped multiple origins and genetic variation detected in these B. hybridum populations opens the way to future evolutionary analysis of allopolyploid formation and genomic dominance and expression in the B. hybridum–B. distachyon–B. stacei grass model complex.info:eu-repo/semantics/publishedVersio

Findings to the flora of Russia and adjacent countries: New national and regional vascular plant records, 4

With this paper we continue a new annual series, the main purpose of which is to make significant floristic findings from Russia and neighboring countries more visible in Russia and abroad. In total, this paper presents new records for 48 vascular plant species from 6 Eurasian countries, obtained during field explorations, as well as during taxonomic revisions of herbarium materials. For the first time, a new locality of Leontopodium leiolepis is recorded for Russia, Rheum uzengukuushi for China, Rorippa prolifera for Lithuania, Lappula marginata for Kyrgyzstan and Tajikistan, Anthriscus caucalis, Chenopodium ficifolium, Euphorbia prostrata for Uzbekistan, Adonis × hybrida, Potamogeton × franconicus, Solidago × niederederi for the Asian part of Russia, Echinochloa esculenta, Poa jamalinensis, Puccinellia poecilantha for Siberia, Potentilla intermedia for the Caucasus, Rhynchospora alba for the Russian part of Altai, Poa sphondylodes, Veronica beccabunga for Eastern Siberia, Asclepias syriaca for the Republic of Altai, Chimaphila umbellata, Orobanche korshinskyi, Veronica scutellata for the Republic of Buryatia, Cirsium alatum, Thalictrum simplex for the Republic of Crimea, Thymus rariflorus, Th. terekensis for the Republic of Ingushetia, Berberis thunbergii, Crataegus maximowiczii, Prunus serotina for the Republic of Mordovia, Oenothera villosa for the Republic of Tatarstan, Astragalus sulcatus, Galium mollugo for the Republic of Tyva, Phragmites altissimus for the Chelyabinsk Region, Senecio dubitabilis for the Magadan Region, Asclepias syriaca, Galatella villosa, Potentilla recta for the Novosibirsk Region, Dodartia orientalis for the Omsk Region, Viola hultenii for the Sakhalin Region, Phragmites tzvelevii for the Samara Region and the Middle Volga, Jacobaea ferganensis for the Samara Region, Carex media, Impatiens parviflora for the Tyumen Region. There are some more findings which are not new for the region but they contribute significantly to the understanding of species distribution

New Insight into the History of Domesticated Apple: Secondary Contribution of the European Wild Apple to the Genome of Cultivated Varieties

The apple is the most common and culturally important fruit crop of temperate areas. The elucidation of its origin and domestication history is therefore of great interest. The wild Central Asian species Malus sieversii has previously been identified as the main contributor to the genome of the cultivated apple (Malus domestica), on the basis of morphological, molecular, and historical evidence. The possible contribution of other wild species present along the Silk Route running from Asia to Western Europe remains a matter of debate, particularly with respect to the contribution of the European wild apple. We used microsatellite markers and an unprecedented large sampling of five Malus species throughout Eurasia (839 accessions from China to Spain) to show that multiple species have contributed to the genetic makeup of domesticated apples. The wild European crabapple M. sylvestris, in particular, was a major secondary contributor. Bidirectional gene flow between the domesticated apple and the European crabapple resulted in the current M. domestica being genetically more closely related to this species than to its Central Asian progenitor, M. sieversii. We found no evidence of a domestication bottleneck or clonal population structure in apples, despite the use of vegetative propagation by grafting. We show that the evolution of domesticated apples occurred over a long time period and involved more than one wild species. Our results support the view that self-incompatibility, a long lifespan, and cultural practices such as selection from open-pollinated seeds have facilitated introgression from wild relatives and the maintenance of genetic variation during domestication. This combination of processes may account for the diversification of several long-lived perennial crops, yielding domestication patterns different from those observed for annual species