Epichloë Endophyte-Promoted Seed Pathogen Increases Host Grass Resistance Against Insect Herbivory

Plants host taxonomically and functionally complex communities of microbes. However, ecological studies on plant–microbe interactions rarely address the role of multiple co-occurring plant-associated microbes. Here, we contend that plant-associated microbes interact with each other and can have joint consequences for higher trophic levels. In this study we recorded the occurrence of the plant seed pathogenic fungus Claviceps purpurea and aphids (Sitobion sp.) on an established field experiment with red fescue (Festuca rubra) plants symbiotic to a seed transmitted endophytic fungus Epichloë festucae (E+) or non-symbiotic (E–). Both fungi are known to produce animal-toxic alkaloids. The study was conducted in a semi-natural setting, where E+ and E– plants from different origins (Spain and Northern Finland) were planted in a randomized design in a fenced common garden at Kevo Subarctic Research Station in Northern Finland. The results reveal that 45% of E+ plants were infected with Claviceps compared to 31% of E– plants. Uninfected plants had 4.5 times more aphids than Claviceps infected plants. By contrast, aphid infestation was unaffected by Epichloë symbiosis. Claviceps alkaloid concentrations correlated with a decrease in aphid numbers, which indicates their insect deterring features. These results show that plant mutualistic fungi can increase the infection probability of a pathogenic fungus, which then becomes beneficial to the plant by controlling herbivorous insects. Our study highlights the complexity and context dependency of species–species and multi-trophic interactions, thus challenging the labeling of species as plant mutualists or pathogens.

Phytoremediation Potential of Flowering Plants in Relation to Copper

Heavy metals such as cadmium, chromium, nickel, mercury, lead, copper, zinc and others are among the priority environmental pollutants. Determination of their content in its main subsystems is an obligatory component in environmental monitoring and certification of agricultural products. On the other hand, all metals are natural components of soil-forming rocks, and some metals are classified as biogenic microelements, and their absence provokes functional disorders in living organisms. This article describes the results of studying the phytoremediation potential of flowering plants in relation to copper ions under laboratory conditions. The following flowering plants were selected as test crops: tansy phacelia, white mustard, small-flowered marigolds and a mixture of cereal grasses consisting of red fescue, perennial ryegrass and bluegrass in a ratio of 40%, 50%, 10%, respectively. Within the experiment, copper ions in concentrations of 2 and 10 maximum permissible concentration (MPC) were introduced into the soil sampled from the territory of agricultural lands (leached medium-thick heavy loamy chernozem with a high level of humus, mobile phosphorus and exchangeable potassium and a low level of nitrate nitrogen, copper in gross and mobile forms). It was found that all plants selected as test crops are capable of accumulating copper ions from the soil to varying degrees, which makes it possible to use them in phytoremediation of agricultural lands planned for organic farming. The ability to accumulate copper ions increases in the following order: white mustard < small-flowered marigolds < tansy phacelia < mixture of cereal grasses. The maximum effect of soil phytoremediation was revealed in the variant with a mixture of cereal grasses. When they are grown, the content of copper ions in the soil with the introduction of 2 MPC decreases by 38.8%, with the introduction of 10 MPC the concentration decreases by 47.8%.

SELECTION EVALUATION OF THE SOURCE MATERIAL OF FESTUCA RUBRA L. OF THE LAWN DIRECTION

The aim of the research was to assess the breeding value of the source material of F. rubra of the lawn direction obtained under conditions of various ecotopes of the south of the Central Russian Upland with a predominance of carbonate substrate. In total, 106 numbers of red fescue of various genetic and geological-geographical origin were evaluated in the experiment: 4 varieties and 102 breeding samples. Tests of the breeding value of the collection numbers were carried out in comparison with the zoned varieties of domestic selection (‘Veselka’, ‘Gostenka’, ‘Iskrinka’) and foreign selection (‘Gondolin’). The forms of F. rubra have been identified, approaching erect in shape, having a high shoot-forming ability, pronounced antocian color of inflorescences, whitish bloom on the leaves, which increases the overall decorative effect of lawn herbage. According to a number of important traits for breeding for seed productivity, the forms selected in natural habitats with a predominance of carbonate substrate have wide limits of variation and can serve as genetic sources of individual breeding traits for obtaining new varieties of lawn management with high seed productivity and decorativeness.

Genetic Diversity of the Symbiotic Fungus Epichloë festucae in Naturally Occurring Host Grass Populations

Epichloë festucae is a common symbiont of the perennial and widely distributed cool season grass, Festuca rubra. The symbiosis is highly integrated involving systemic growth of the fungus throughout above-ground host parts and vertical transmission from plant to its offspring via host seeds. However, the nature of symbiosis is labile ranging from antagonistic to mutualistic depending on prevailing selection pressures. Both the loss of fungus in the maternal host lineage and horizontal transmission through sexual spores within the host population may partly explain the detected variation in symbiosis in wild grass populations. Epichloë species are commonly considered as pathogens when they produce sexual spores and partly castrate their host plant. This is the pathogenic end of the continuum from antagonistic to mutualistic interactions. Here we examined the population genetic structure of E. festucae to reveal the gene flow, importance of reproduction modes, and alkaloid potential of the symbiotic fungus in Europe. Epichloë-species are highly dependent on the host in survival and reproduction whilst benefits to the host are largely linked to defensive mutualism attributable to fungal-origin bioactive alkaloids that negatively affect vertebrate and/or invertebrate herbivores. We detected decreased genetic diversity in previously glaciated areas compared to non-glaciated regions during the last glacial maximum period and found three major genetic clusters in E. festucae populations: southern, northeastern and northwestern Europe. Sexual reproduction may have a higher role than expected in Spanish E. festucae populations due to the predominance of unique genotypes and presence of both mating types in the region. In contrast, asexual reproduction via host seeds predominates in the Faroe Island and Finland in northern Europe due to the presence of biased mating-type ratios and large dominant genotypes in the E. festucae populations within the region. A substantially larger variation of alkaloid genotypes was observed in the fungal populations than expected, although the variability of the alkaloid genotypes within populations is considerably lower in northern than Spanish populations in southern Europe. E. festucae populations consist of different combinations of alkaloid classes from the gene clusters of ergot alkaloid and indole-terpenes, and from pyrrolopyrazine alkaloid gene. We suggest that the postglacial distribution history of the host grass, prevailing reproduction strategies of E. festucae, and local selection pressures likely explain a large part of the genetic variation observed in fungal populations among geographic regions. The identified alkaloid genotypes can be used by turfgrass breeders to improve resistance against herbivores in red fescue varieties and to develop new sustainable cultivars in Europe.

The variety trial of lawn red fescue in the Western Caucasus and Central Chernozem Region

В 2017–2020 годах проведены экологические испытания существующих сортов и новых селекционных образцов овсяницы красной, созданных на основе исходного материала, полученного из местных популяций, произрастающих в различных экотопах мелового юга Среднерусской возвышенности. Объектом изучения были сорта овсяницы красной газонного типа Россинант (стандарт), Гостёнка, Искринка, Везёлка и 14 селекционных образцов, выделившихся в селекционном питомнике по комплексу морфо-биологических признаков, характерных для сортов газонного направления. Опыты проводили в трёх экологических точках: г. Геленджике (Краснодарский край); пгт Новомихайловский (Туапсинский район Краснодарского края); с. Драгунское (Белгородский район Белгородской области). Изучали продуктивность побегообразования, выраженную в среднем количестве сформированных побегов в год, и урожайность зелёной массы. Установлено, что исходный материал обладает высокой побегообразующей способностью и невысокой надземной продуктивностью, сопоставимыми с сортами, широко используемыми в газонных культурфитоценозах. Анализ корреляции между изучаемыми признаками показал, что в условиях юга Среднерусской возвышенности (экологическая точка «Белгородская область») с высокой вероятностью можно вести селекционную работу и отбор ценных генотипов овсяницы красной для условий Черноморского побережья Западного Кавказа по признаку «Среднегодовой прирост побегов». Показана корреляционная связь этого признака между экологическими точками «г. Геленджик» и «Белгородская область», подтверждённая достоверной корреляцией рангов Спирмена средней силы (rs = 0,446, P > 0,05). Не установлено тесной связи между урожайностью зелёной массы в экологической точке «Белгородская область» и экологических точках Западного Кавказа. В связи с этим для оценки селекционного материала необходимо проводить широкие экологические испытания исходного материала в экологических точках регионов, в которых предполагается использовать перспективные сорта. Сделано заключение о возможности использования исходного селекционного материала мелового юга Среднерусской возвышенности для создания сортов газонного направления для условий Западного Кавказа. The variety trial for red fescue genotypes tool place in 2017–2020. Local populations growing in the south of the Central Russian Upland were used as parental material to obtain the genotypes. The following lawn varieties were tested: “Rossinant” (standard), “Gostenka”, “Iskrinka”, “Vezelka” as well as 14 other genotypes carrying the number of valuable traits. Plants were grown in three different locations: Gelendzhik; the Tuapse region; the Belgorod region. The trial tested the average number of shoots formed in a year as well as green mass productivity. Parental lines actively formed shoots but had low productivity similar to widely cultivated lawn varieties. Red fescue genotypes with high annual shoot yield were widely spread in Gelendzhik and the Belgorod region (rs = 0.446, P > 0.05). The correlation between green mass productivity and the Belgorod region were insignificant same as for the Western Caucasus. It is highly important to test parental lines in the area of respective cultivation. Parental material from the south of the Central Russian Upland can be used to develop lawn genotypes for the Western Caucasus.

The influence of the grass mixture composition on the quality and suitability for football pitches

The selection of grass mixtures with appropriate visual and functional parameters for sowing football fields is a key element in shaping the sports infrastructure, ensuring the spectacularity of a match and comfort for players. The aim of the research was to investigate the properties of lawn grass mixtures and their suitability for football pitches. The experiment was conducted at the Toya Golf & Country Club (51° 20′ E, 17° 07′ N), Wrocław, Poland, between 2007 and 2009. 12 grass mixtures were selected, mainly based on red fescue, Kentucky bluegrass, and perennial ryegrass. The assessment was carried out using a nine-point scale, according to the Plant Variety Office methodology for crops and turf grass. Six features of sports turf were studied: appearance, density, colour, leaf fineness, overwintering, and susceptibility to disease and they significantly varied, depending on the grass mixture and the year of research. Our study showed that mixtures based on the dominance of meadow grass were characterized by higher values of the general visual aspect, colour and slenderness of the leaf blade and these based on the dominance of perennial ryegrass and co-dominance of perennial ryegrass and meadow grass were the most useful in terms of wintering, resistance to diseases and sodding.

The Allelopathic Potential of Rosa blanda Aiton on Selected Wild-Growing Native and Cultivated Plants in Europe

Invasive plant species are responsible for changing colonized ecosystems by occupying new areas and creating a threat to the functioning of the native flora and fauna populations. Alien plants can produce allelochemicals, substances completely new to indigenous communities. This study investigated the germination seed reactions of Festuca rubra L. and Raphanus sativus L. var. radicula Pers. cv. Rowa on the extracts from the roots, stalks, leaves, and flowers of Rosa blanda. Aqueous extracts at concentrations of 1%, 2.5%, and 5% were used in order to determine the allelopathic potential of this alien rose for Europe. With the increase in the concentration of extracts, a decrease in the germination capacity of seeds of the tested species was observed. R. blanda extracts inhibited the growth of seedlings. Depending on the concentration and type of the extract, changes in biomass and water content in Red Fescue and Red Radish seedlings were also shown. The highest differences in the electrolyte leakages were noted in seedlings treated with 5% rose extracts. The study showed that the aqueous extracts of R. blanda leaves and flowers had the greatest allelopathic potential.

INFLUENCE OF LONG-TERM APPLICATION OF FERTILIZERS ON BOTANICAL COMPOSITION OF HAYFIELD PHYTOCENOSIS AND THE QUALITY OF THE RECEIVED FODDER

In the Federal Williams Research Center of Forage Production and Agroecology in 1947 the study of the effectiveness of mineral and organic fertilizers was started. For 74 years of using the herbage without re-sowing, the features of succession variability have been revealed. There was a reformation of the seeded legume-grass herbage into two types: low grass-legume-motley grass against the background of the use of one- and two-component mineral fertilizers and manure (regressive succession) and grass-motley grass with the application of complete mineral fertilizer with high doses of nitrogen (progressive succession). On the herbage of the first type, the predominant species is the introduced species — red fescue (43.8–75.4%), on the herbage of the second type — high grasses (meadow foxtail, cocksfoot, awnless brome). The reformation of the herbage did not lead to a decrease in yield. Over the past 28 years (average for 1993–2020), the yield of herbage with regressive succession exceeded the control (3.3 t/ha dry matter) by 1.1–1.9 times, with progressive succession by 1.9–2.6 times. The annual consumption of nitrogen by grasses in the control was 54 kg, P2O5 — 14 kg, K2O — 46 kg. The application of one- and two-component mineral fertilizer and manure increases the consumption of nitrogen by 1.1–2.4 times, phos-phorus — by 1.3–3.1 times, potassium — by 1.3–3.6 times, the application of complete mineral fertilizer, respectively, in 2.3–3.5, 2.9–3.9 and 2.4–3.9 times. The quality of the received feed for the content of crude protein, crude fiber and crude ash on both types of herbage met the requirements of standard for the first and second class. The content of mineral elements also met the zootechnical standards.