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EN
In the managed forest of temperate Europe, black cherry (Prunus serotina) is one of the most important invader species. Among the ecological traits enabling its expansion in forest stands, the role of chemical compounds released naturally by this plant into the environment still remains unclear. The aim of this study was to determine the influence of black cherry leaf litter on the germination and growth of Scots pine (Pinus sylvestris) seedlings. Laboratory bioassays with extracts from newly fallen and decomposed leaves showed a phytotoxic effect on root elongation and a slightly weaker negative effect on stem growth of pine shoots. The inhibitory effect increased with the gradient of leaf extract concentration. Furthermore, a significant negative correlation was observed between condensed tannin content in decomposed leaf litter of the black cherry and the pine root growth. The results are discussed in the context of black cherry litter properties which could interfere with natural regeneration of pine forests.
EN
The role of allelopathy in the displacement of given meadow species by wood small-reed (Calamagrostis epigejos) is not well recognized. The aim of this study was to evaluate and compare the influence of volatile and aqueous extracts from C. epigejos on initial recruitment of typical mesic meadow species (Daucus carota, Rumex acetosa, Festuca pratensis and Dactylis glomerata). The activity of allelochemicals contained within above-ground biomass, below-ground biomass and necromass of the donor plant was estimated. Using gas chromatography-mass spectrometry technique led to the identification of 19 compounds (alcohols, aldehydes, ketones and esters) in C. epigejos volatile extracts. Aliphatic alcohols were the main group of identified chemicals, including (Z)-3-hexen-1-ol acetate. The laboratory tests showed a significant inhibitory influence of volatile C. epigejos extracts on the growth of D. glomerata, D. carota and R. acetosa roots. The influence of aqueous C. epigejos extracts on selected meadow species was less evident. Only the seeds of D. glomerata and F. pratensis were found to be susceptible to water extracts of above-ground C. epigejos biomass. The seed germination was stimulated by the extracts at low concentrations but inhibited at higher concentrations. Among the tested plants only the growth of F. pratensis seedlings was inhibited by aqueous extracts obtained from all examined C. epigejos parts. In regarding to the other test species the effect of C. epigejos extracts was neutral or positive. The results suggest that C. epigejos has a allelopathic potential to suppress the growth of co-occurring grassland species.
EN
Even though Alliaria petiolata is a globally important invasive plant, for Europe it is a native humble understory species. I studied the population characteristics of A. petiolata in its native range (NE Slovenia) by evaluating its demographic structure (e.g. population size, density, plant fruit production) and herbivory damage in different habitats (forest understorey, forest edge, ruderal site). Moreover I tested the allelopathic potential of fresh A. petiolata leaves and roots on garden cress Lepidium sativum germination and seedling development. I performed bioassays with aqueous extracts and took a first step toward testing the presence of volatile potentially allelopathic compounds. The results showed that A. petiolata populations can become established at disturbed sites, even such without a tree canopy, but dense stands can be found only at disturbed forest edges. The bioassays confirmed the presence of A. petiolata aqueous and volatile allelochemicals in leaves and roots. Germination was suppressed more by volatiles, showing that allelopathy can act via volatile compounds and further suggesting their antifungal effects. The results allow predicting that the success of A. petiolata invasion in a non-native range might rely on its variable habitat tolerance (not being a strict ruderal species) and allelopathy.
PL
Plon i jakość nasion są ważnymi parametrami decydującymi o efektywności produkcji rolniczej. Zależą one od cech genetycznych, i warunków środowiskowych, w tym: wody, temperatury, nawożenia, naświetlenia, a także od umiejscowienia nasion na roślinie, które ma wpływ na okres ich dojrzewania i zbioru. Zwiększenie wielkości i jakości plonu nasion można uzyskać stosując niechemiczne metody agrotechniczne, stymulowanie lub hamowanie wzrostu sąsiadujących roślin wykorzystując zjawisko allelopatii, biologiczne traktowanie rozwijających się roślin i nasion, poprawę kwitnienia i zapylania kwiatów, przedsiewne uszlachetnianie nasion, zwiększenie odporności siewek na chłód i choroby oraz spowolnienie starzenia się materiału siewnego. Wyodrębnione metody mają charakter ekologiczny i sprzyjają środowisku.
EN
Yield and quality of seeds decide about the effectiveness of plant production. They are dependent not only on the genera but also on environmental conditions, such as water, temperature, nutrition, light, as well as localisation of seeds on plants, which influence on the time of seed maturation and their harvest. Increase of yield and quality of seeds can be achieved by use of agro technical methods, regulation of plant development basing on the allelopathy between organisms, physiological and biological treatments of developed plants and seeds, improving flowering and pollination, pre-sowing seed processing and conditioning, increasing resistance to chilling, improving the health status of seeds and decreasing their ageing. The used methods are ecological and friendly for environment.
EN
Allelopathy may be one of the factors affecting the formation of massive and harmful algal blooms in aquatic environments. Recent studies indicate that blooms of cyanobacteria in the Baltic Sea has grown significantly in last decades, so it is important to determine the allelopathic interactions between the dominant species of cyanobacteria and microalgae. In this work we investigated the influence of allelopathic compounds on the growth of Skeletonema marinoi by addition of cell-free filtrate of the Baltic cyanobacterium Nodularia spumigena cultures grown under different temperature (15-25ºC). Additionally the effects of filtrates of both an exponential and a stationary growing culture of N. spumigena were tested on diatom. These studies indicate that high temperature affected the donor species by increasing its production of allelochemicals. The highest drop of growth of analyzed diatom were observed after the addition of cell-free filtrate obtained from N. spumigena grown at 25ºC and constituted 70% of their control. N. spumigena was only allelopathic in exponential growth phase, whereas the cyanobacteria filtrate from stationary phase have any effect on S. marinoi. These findings suggest that N. spumigena may reveal allelopathic activity and that the production of allelopathic substances is influenced by the temperature and growth phase of cyanobacteria.
PL
Allelopatia może być kluczowym czynnikiem wpływającym na tworzenie się masowych zakwitów sinic w wielu wodnych ekosystemach. Badania pokazują, że zakwity sinic w Morzu Bałtyckim w ostatnich dekadach znacznie się nasiliły, dlatego tak ważne jest określenie stopnia oddziaływania allelopatycznego dominujących w tym akwenie gatunków fitoplanktonu. W przeprowadzonych badaniach określono wpływ związków allelopatycznych produkowanych przez bałtycką sinicę Nodularia spumigena hodowaną w różnych temperaturach (15-25ºC) na wzrost okrzemki Skeletonema marinoi. Dodatkowo w niniejszej pracy porównano wpływ przesączu komórkowego uzyskanego z hodowli sinic będących w fazie logarytmicznego i stacjonarnego wzrostu. Badania wykazały, że temperatura modyfikuje allelopatyczne oddziaływania i na przykład najwyższy spadek wzrostu zaobserwowano u S. marinoi po dodaniu przesączu uzyskanego z kultur N. spumigena hodowanych w 25ºC. Wynosił on 70% w stosunku do kontroli. Ponadto w pracy stwierdzono, że N. spumigena wykazywała oddziaływanie allelopatyczne na badaną okrzemkę jedynie wtedy, gdy dodawany przesącz komórkowy pochodził z fazy logarytmicznego wzrostu. Wyniki uzyskane w niniejszej pracy sugerują, że bałtyckie sinice mogą wykazywać oddziaływania allelopatyczne w stosunku do okrzemek a produkcja związków allelopatycznych może być zależna od temperatury oraz fazy wzrostu, w której znajdują się organizmy donorowe.
EN
Competition is an evolutionary mechanism which exerts a selection pressure on living organisms. Forest trees compete for light, water and nutrients, especially at a young age. It was observed that the Quercus petraea and Padus serotina natural regenerations occupied the same site growing under the canopy of Scots pine (Pinus silvestris L.). To simulate the competition between young sessile oaks and black cherries found in forest, a controlled experiment was conducted using one-year-old seedlings of both species. There were eight treatments of different competition intensity. The treatments were established varying the number of potted seedlings and adding fresh cherry leaves to the substrate to enhance allelopathic effects. It was hypothesized that black cherry would reduce the height growth and diameter at root collar of sessile oak seedlings and this inhibitory effect would be magnified by an increasing number of cherry seedlings and/or fresh leaves. Black cherry as an invasive, fast-growing species was presumed to win the growth competition with oak. However, the differences in growth parameters would not only depend on genetic differences between the species, but also on the number of competing seedlings in pots and an allelopathic effect of cherry leaves. During the whole vegetative season, each two weeks, the growth parameters of seedlings (height, height increment and diameter at root collar) were measured. The results did not support the hypothesis that cherry had an inhibitory effect on oak growth, at least after one vegetative season. Contrary, a presence of cherry seedlings enhanced the oak height increment (F = 8.6, P <0.001) which might be due to either the strong interspecific competition for light or, less plausibly, positive allelopathic effect, or an interaction of both. Our results indicated a negative auto-allelopathic effect of cherry seedlings and/or fresh cherry leaves on height of cherry seedlings (F = 47.7, P <0.001). This invader showed a continuous and steep height increment within the whole vegetative season, whereas oak seedlings grew rapidly only in July. When compared the mean initial heights in April with those after the bud set in September, cherry was four fold and oak only two fold higher. A very intensive height increment gives black cherry an advantage over sessile oak at a young age which can disturb the spontaneous conversion of pine stands into a mixed pine-oak forest with a greater share of oak and other native deciduous tree species.
7
EN
Miscanthus × giganteus (Giant Miscanthus) is one of the most promising plants cultivated for biomass production. In spite of its origin from south-east Asia and being warm adapted plant it grows well and produces high biomass in temperate latitudes. Miscanthus × giganteus is a C4 plant and hence this study presents a brief description of C4 photosynthesis and the enzymes involved in this process. On the basis of data from current literature, the biochemical bases of relatively high tolerance of miscanthus to cold temperatures (0–15 oC) were evaluated. Moreover, it was reviewed numerous ecophysiological features of Miscanthus × giganteus were reviewed (high productivity, low fertiliser and pesticides requirements, possibility to use in phytoremediation) which showed that it is a proecological and environmentally friendly crop. This causes that Miscanthus × giganteus might be recognize as a leading crop in non-food cultivations.
PL
Miscanthus × giganteus (Miskant olbrzymi) jest jedną z bardziej obiecujących tzw. Roślin alternatywnych uprawianych z przeznaczeniem na cele energetyczne. Pomimo że pochodzi z południowo- Miscanthus -wschodniej Azji i jest rośliną ciepłolubną, to bardzo dobrze rośnie i charakteryzuje się wysoką produktywności ą w strefie umiarkowanych szerokości geograficznych. Miscanthus × giganteus jest rośliną typu C4, dlatego w pracy przedstawiono krótki opis procesu fotosyntetycznego wiązania CO2 w tzw. szlaku C4 oraz uczestniczących w nim enzymów. Korzystając z najnowszych danych literaturowych, przeanalizowano podstawy biochemiczne stosunkowo dużej odporności tej rośliny na niskie temperatury (0-15 oC). Opisano również szereg ekofizjologicznych właściwości Miscanthus × giganteus (wysoka produktywność, niewielkie wymagania nawozowe, brak konieczności stosowania pestycydów, możliwość wykorzystania w procesach fitoremediacji), które sprawiają, że jest on określany jako roślina ekologiczna i szczególnie przyjazna środowisku. Opisane cechy rośliny sprawiają, że można ją uznać za lidera wśród roślin uprawianych na cele nieżywnościowe.
8
Content available remote Allelopatyczne właściwości metabolitów wtórnych roślin uprawnych
EN
Allelopathy has been defined by the International Allelopathy Society as "any process involving secondary metabolites produced by plants, microorganisms, viruses and fungi that influence the growth and development of agricultural and biological systems, including positive and negative effects [1]". Allelochemicals can be released into the environment and despite what effect they evoke towards living organisms this kind of specific chemical interactions is known as "allelopathy". Allelopathic phenomena have been observed and studied from ancient times. Theophrastus from Eresos, a disciple of Aristotle, reported an inhibitory effect of pigweed Polygonum spp. on alfalfa in ca. 350 B.C., whereas Pliny described the harmful effects of several plants on cropland in ca. 1 A.D. [2-5]. Although chemical interactions between plants have been known for thousands years, the term allelopathy was used for the first time in 1937 [5]. It derives from Latin words allelon ("of each other") and pathos ("to suffer") and refers to the chemical interactions among species. In recent years there has been an increasing interest towards the perspective of exploiting allelopathy and allelochemicals as an alternative strategy for controlling weeds in particular, but also for controlling insects and plant diseases. Plants produce a wide variety of secondary metabolites that play important roles in ecological interactions. This is one, probably the most pronounced, of a variety of ways in which certain plants can protect themselves against competition, infection or feeding in their natural habitats. Some of secondary metabolites may also play an important role in chemical mediation of growth and development of plant communities. These substances are called "allelochemicals" and are relea-sed into the environment in order to interfere with the growth of competing plants or act as chemical defence against pathogens and animals. Therefore such compounds might be considered as constituents of plant defence system and could be treated as a kind of chemical weapons. Originally, compounds like allelochemicals were thought to occur exclusively in higher plants. Ongoing research, however, has revealed them also to be synthesized by bacteria, lower plants and fungi. Allelochemicals may furnish an entirely new generation of naturally produced weed-controlling compounds, replacing synthetic herbicides and other pesticides with non-acumulatting easy-degradable substances.
PL
Allelopatia to wzajemne oddziaływania roślin na siebie poprzez wydzielane związki chemiczne, które mogą działać stymulująco lub inhibitująco na rozwój innych roślin.Allelopatycznie działające związki chemiczne mogą być wydzielane do abiotycznych elementów środowiska(powietrza,gleby i wody) zarówno przez żywe jak też obumarłe i ulegające rozkładowi organizmy roślinne. Celem niniejszego artykułu jest przedstawienie oddziaływań allelopatycznych niektórych roślin na inne rosliny i zwierzęta oraz możliwości pełniejszego wykorzystania tych właściwości w produkcji rolniczej.
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