Additions to the «Flora...» by P. F. Maevsky (2014) for the Penza Region

Records of 94 vascular plant species from the Penza Region published before 2013 are missing from the 11th edition of the «Flora of the Central Part of European Russia» by P. F. Mayevsky (2014). An additional 22 species were discovered in the region recently. At least 29 species known in the Penza Region are completely missing from the «Flora…» – Stellaria subulata Boeber ex D. F. K. Schltdl., Polygala vaillantii Bess., Lotus zhegulensis Klokov, Astragalus olgianus Krytzka, Alchemilla hians Juz., Alchemilla homoeophylla Juz., Alchemilla lessingiana Juz., Alchemilla macrescens Juz., Alchemilla mininzonii Czkalov, Alchemilla pustynensis Czkalov, Alchemilla schmakovii Czkalov, Alchemilla tichomirovii Czkalov, Alchemilla tzvelevii Czkalov, Alchemilla vorotnikovii Czkalov, Jurinea charcoviensis Klokov, Carduus stenocephalus Tamamsch., Pilosella suecica (Fries) F. W. Schultz et Sch. Bip., Artemisia nitrosa Weber ex Stechm., Thymus goginae Vasjukov, Glandularia tenuisecta (Briq.) Small, Typha × soligorskiensis D. Dubovik, Juncus turkestanicus V. Krecz. et Gontsch., Koeleria dubjanskyi Tzvelev, Koeleria macrantha (Ledeb.) Spreng., Koeleria spryginii Tzvelev, Koeleria valdevestita Tzvelev, Agrostis breviramea (Roshev. ex Tzvelev) Kurczenko, Festuca spryginii Tzvelev, Echinochloa tzvelevii Mosyakin ex Mavrodiev et H. Scholz. A list of additions based upon specimens and published references is presented.

Plants with Horticultural and Ecological Attributes for Green Roofs in a Cool, Dry Climate

Green roofs are building surface treatments where plants are grown in medium on a rooftop to cool or insulate buildings and/or to ameliorate negative environmental impacts of buildings. We initiated a 2-year study to characterize medium and weather conditions on a rooftop in a cool-dry climate and to identify plant species with horticultural and ecological attributes that survive and thrive on an unirrigated semi-intensive green roof in a cool-dry climate. Eighty-eight cold-hardy, drought-tolerant species with horticultural or ecological attributes were identified and planted into 12.7-cm-deep medium in trays that were placed on a rooftop. Medium temperatures and moistures were recorded, and plant survival and vigor were quantified. Hourly medium temperatures varied from –22.3 to 43 °C. Monthly medium water moistures varied from –2.5 to –73.3 kPa from May to September, and from –7.6 to –195 kPa from October to April. Monthly air temperature, relative humidity and irradiance varied from –9.4 to 21.7 °C, 44% to 80%, and from 206 to 1222 μmol·m−2·s−1. Mean survival scores decreased (4 = 100% survival) from 2.6 with grasses, to 2.3 with succulents, to 1.8 with temperate perennials, to 0 for geophytes (all died). Among grasses, Festuca ovina VNS, Koeleria macrantha 07-901 ND, Panicum virgatum, and Sporobolus heterolepis performed well. Among succulents, Sedum acre, S. album ‘Coral Carpet’, S. cauticola ‘Sunset Cloud’, S. ‘Czar’s Gold’, S. ellecombianum, S. hybridum ‘Immergruchen’, S. requieni, S. sexangulare, S. spurium ‘Dragon’s Blood’, ‘John Creech’, ‘Pearly Pink’, ‘Ruby Mantle’, and ‘Tricolor’ performed well. Among temperature nonsucculent perennials, Allium ceranum and senescens ‘Glaucum’, Geum triflorum, Talinum calycinum, and Thymus praecox ‘Red Creeping’ performed well. Data on Sedum suggested that medium-low temperature was more limiting to survival than moisture level. The differences in species that performed well here, compared with other studies, underscores the importance of regionally specific green roof plant species studies.

Broad-sense Heritability Estimates of Turfgrass Performance Characteristics in Native Prairie Junegrass Germplasm

Prairie junegrass [Koeleria macrantha (Ledeb.) Shultes] is a perennial, short-grass prairie species distributed throughout the Northern Hemisphere that is being evaluated for use as a low-input turf. In June 2007, 300 genotypes representing collection locations derived from Colorado, Nebraska, and Minnesota germplasm were grown and evaluated 3 years for turfgrass performance characteristics in a randomized complete block design with five clonal replications at two locations (St. Paul, MN, and Becker, MN). After establishment, plots received no supplemental irrigation or fertility and were mowed weekly to a height of 6.4 cm. Broad-sense heritability estimates were calculated on a clonal mean (Hc) and single-plant (Hsp) basis for turf quality (Hc = 0.62, Hsp = 0.13), crown density (Hc = 0.55, Hsp = 0.09), mowing quality (Hc = 0.59, Hsp = 0.09), and genetic color (Hc = 0.45, Hsp = 0.06). The heritability estimates indicate that selection for these traits should result in significant gains in germplasm improvement. Differences were observed in the means and variances among clones, collection locations, and/or collection regions for many of the traits evaluated including rust severity (Puccinia spp.), spring green-up, plant height, lateral spread, vertical regrowth, and flowering traits. The positive correlations among some of these traits and those with moderate heritability estimates should allow for multi-trait selection in cultivar development.

Antioxidative Responses and Candidate Gene Expression in Prairie Junegrass under Drought Stress

Prairie junegrass (Koeleria macrantha) is a native cool-season C3 grass that has shown potential as a low-input turfgrass. An increased understanding of the physiological and molecular responses of prairie junegrass to water-deficit conditions is important for developing cultivars with enhanced drought tolerance. The objective of this study was to characterize the antioxidative responses and candidate gene expression in prairie junegrass subjected to drought stress. Two drought-tolerant (TOL-1 and TOL-2) and two drought-susceptible (SUS-1 and SUS-2) genotypes of prairie junegrass were subjected to 7 days of drought stress. Leaf relative water content (RWC) of SUS-1 and SUS-2 was 72.1% and 73.8% and RWC of TOL-1 and TOL-2 was 90.1% and 85.4% in drought-stressed plants, respectively. Drought stress did not affect chlorophyll fluorescence, lipid peroxidation, and antioxidative enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase, ascorbate peroxidase (APX), or glutathione reductase for tolerant or susceptible genotypes. The TOL-2 and SUS-2 genotypes were further examined for candidate gene expression. Drought stress did not alter expression levels of CAT and chloroplastic copper/zinc SOD (Cu/ZnSOD), but increased levels of APX in either genotype, compared with their relative controls. Expression of P5CS encoding Δ1-pyrroline-5-carboxylate synthetase and P5CR encoding Δ1-pyrroline-5-carboxylate reductase for proline biosynthesis were up-regulated under drought stress for both genotypes; however, expression of P5CR was more strongly induced under drought stress for TOL-2, compared with its control. The expression of 1-FFT encoding fructan:fructan 1-fructosyltransferase, which is involved in fructan biosynthesis, was strongly induced under drought stress for TOL-2 but not detected under either control or drought stress conditions for SUS-2. These results indicate that the genes involved in proline and fructan biosynthesis may play an important role in drought tolerance in prairie junegrass.

Threatened dry grasslands in the continental boreal forests of Wood Buffalo National Park: commentary

There are three primary types of graminoid-dominated communities in or near Wood Buffalo National Park, Canada: freshwater meadows and marshes composed of Calamagrostis canadensis (Michx.) Beauv., Carex atherodes Spreng., Carex aquatilis Wahlenb., Scolochloa festucacea (Willd.) Link, and Poa L.; saline meadows composed of Hordeum jubatum L., Puccinellia nuttalliana (Schult.) A.S. Hitchc.,Agropyron trachycaulum (Link) Malte, Calamagrostis stricta (Timm) Koeler, and Calamagrostis inexpansa A. Gray; and dry grasslands composed of Agropyron trachycaulum, Stipa L., Carex siccata Dewey, Carex obtusata Lilj., and Koeleria macrantha (Ledeb.) J.A. Schultes f. Except for the Peace Point area, it is not known whether dry grasslands have declined in areal extent. Including various wetlands under "dry grasslands", and concluding that these areas no longer support dry grassland is misleading. Dry grasslands exist in Wood Buffalo National Park, but most graminoid-dominated communities in the park are, and have been, freshwater and saline meadows and marshes. A clear understanding of the ecological factors operating in these different ecosystems is critical to informed management.Key words: fire, grassland, prairie, vegetation, wetland, Wood Buffalo National Park.