Two factors which affect leaf ontogeny and ultimate leaf size: (1) the rate and duration of cell expansion, and (2) the rate and duration of cell division, were examined for their role in the slowed early growth rate and smaller ultimate leaf size when plants are exposed to ultraviolet-B (UV-B) radiation. Rumex patientia L. was grown in controlled environment chambers under enhanced UV-B radiation (equivalent to daily solar UV-B irradiation at 40°N latitude in mid-May with an atmospheric ozone concentration of 0.20 atm-cm) and control treatments. The pattern of growth as expressed in changes of mean cell size of two distinct cell types, tissue cell density, and length of the entire blade are consistent with the hypothesis that the radiation primarily affects cell division rather than cell expansion. Furthermore, it appears that the radiation probably alters the rate rather than the duration of cell division. An understanding of the mechanism of radiation damage should facilitate prediction of how this stress may interact with other stresses to which plants are normally subjected.

Wind-pollinated plants often have little genetic structure owing to high gene flow. However, sex chromosomes evolution promotes divergence, potentially leading to population subdivision. Rumex hastatulus (Polygonaceae) is a wind-pollinated, dioecious coloniser of open disturbed land with two sex chromosome races (SCRs), which occupy different parts of the species’ range in the southern USA. My thesis investigated phenotypic and genetic differentiation between the SCRs, based on a study of 28 populations sampled throughout the range. A glasshouse experiment demonstrated significant differentiation between the SCRs in several life-history traits, several of which exhibited clinal variation. Analysis of population genetic structure, based on 13 nuclear loci, revealed two distinct clusters corresponding to the two SCRs, with an estimated origin of the North Carolina SCR from the Texas SCR between ~5000–15000 generations ago. My results indicate that the SCRs have developed a moderate degree of phenotypic and genetic differentiation despite ongoing gene flow.

Der Stumpfblättrige Ampfer (Rumex obtusifolius) ist eine häufig auftretende Schadpflanze des Grünlandes. Er verdrängt wertvolle Futtergräser und beeinträchtigt die Grundfutterqualität und Futterkonservierung negativ. Zahlreiche Publikationen beschäftigten sich mit der Botanik und der allgemeinen Schadwirkung, zu den wirtschaftlichen Auswirkungen wurden bisher kaum belastbare Aussagen veröffentlicht. In 2-jährigen Felderhebungen wurden an 3 Standorten in Sachsen und Thüringen zu jeweils 4 Aufwüchsen die Parameter Abundanz, Deckungsgrad, Ertragsanteil, Trockenmasseertrag sowie Futterwert und Inhaltsstoffe von Ampfer in Relation zu Gras bei unterschiedlich starkem Ampferbefall untersucht. Die Erfassung der projektiven Deckung war deutlich besser zur Quantifizierung des Schadauftretens geeignet als die Abundanz. Der Ertragsanteil betrug das 0,69-fache des Ampfer-Deckungsgrades. Der Gesamt-TM-Ertrag wurde bei steigendem Ampferbefall regelmäßig nicht negativ beeinflusst. Die Energiedichte von Ampfer lag rund 25 % unter der der jeweiligen Graskomponente. Aus dem geringeren Trockenmasseertrag und der niedrigeren Energiedichte ergibt sich bei Ampferbekämpfung und Nachsaat ein Potenzial zur Steigerung des Energieertrages der Fläche. In Silierversuchen wurde die Wirkung von verschiedenen Mischungsanteilen von R. obtusifolius auf den Konservierungserfolg von Lolium perenne untersucht. Steigende Ampferanteile wirkten sich negativ auf das Gärsäuremuster der Grassilagen aus und führten zu einem zusätzlichen Rückgang der Energiedichte der anteiligen Ampferkomponente von rund 10 %. Es wurde ein mathematisches Modell entwickelt, mit dem sich auf Basis der Parameter Gesamt-TM-Ertrag des Bestandes, Energiedichte des Grases, dem Ampfer-Deckungsgrad und unter Einbeziehung des Milchpreises der potenziell entgangene Deckungsbeitrag berechnen lässt. Daraus kann für unterschiedliche Kosten-, Ertrags- und Erlössituationen eine flexible wirtschaftliche Schadensschwelle abgeleitet werden. / Docks are one of most frequently arising problem weeds of the permanent grassland. It suppresses valuable fodder grasses and negatively influences the basic fodder quality. Numerous publications concern themselves with botany and the general side-effect; chargeable statements to economic effects were so far however not published. In two-year field collections at three locations in eastern part of Germany the relations between abundances, coverage, yield part, dry matter yield of grass and docks as well as the worth-giving ingredients of both were analyzed. Different recording methods were comparatively evaluated. Estimating or measuring the weed ground cover was more suitable for quantifying the loss in economic value due to presence of Docks then plant counting’s. The proportional yield part of docks can be derived however surely from the percent of ground cover multiplied by 0.69. The total dry matter yield was regularly not affected by raising colonization of Docks. The net energy of docks was 25 % under that from grass. The low dry matter yield and the reduced net energy content of Docks in comparison to grass appearing a potential for raising net energy yield per hectare after controlling the docks and reestablishing the sward. In ensiling studies the effect of rising mixture portions of docks on preservation success of Italian rye grass was examined. It was stated that docks affects the fermenting acid sample negatively and leads to a proportionate decrease of net energy content of the silage feed of approximately 10 %. A mathematical model has been developed, based on entire dry matter yield of the site, net energy content of the grass, ground canopy of docks and milk proceeds. It allows the forecast of non realized income, which could be used in case of removal of docks and recovering gaps with grass comparably to the existing grass. From this point a flexible economical damage threshold can be derived for different costing, yield and proceeds situations.

Net photosynthesis, dark respiration, chlorophyll concentrations and growth were determined for Rumex patientia L. exposed to UV-B radiation corresponding to reduced atmospheric ozone concentrations. The hypothesis of whether reciprocity is maintained in the response of R. patientia to polychromatic UV-B radiation was tested. On the basis of the relationships derived from these studies, a simulation model was developed for the prediction of photosynthesis and growth of R. patientia exposed to UV-B radiation corresponding to any atmospheric ozone reduction. Photosynthetic rates were found to be depressed after two hours exposure to UV-B irradiance simulating a 0.18 atm•cm ozone column when the sun is at 30° from the zenith. During this initial exposure period, partial stomatal closure was implicated in the suppression of photosynthesis. However, after one day exposure, substantial increases in photosynthetic resistances apart from stomatal diffusion resistance occurred in the UV-irradiated plants and no differences in stomatal diffusion resistance were apparent between UV-irradiated and control plants. Dark respiration rates were slightly higher in those plants exposed to UV radiation. Leaf expansion of R. patientia was substantially repressed but only during the initial few days of exposure. Thereafter, leaf expansion was similar in the UV-irradiated and control plants. A reduction in total plant dry weight and leaf area of approximately 50 percent occurred after 22 days treatment while chlorophyll concentrations remained unaltered. Time of leaf initiation was shawm to be delayed in those plants exposed to UV-B radiation. Leaf longevity was decreased with increased UV radiation but accelerated whole-plant senescence and death was not observed. Photosynthetic rates determined through the ontogeny of the third leaf of R. patientia exposed to four levels of UV irradiance were found to be depressed as a function of the accumulated biologically effective UV irradiation. Thus, reciprocity was demonstrated between 6350 and 3175 J biologically effective UV irradiation. Results of the simultion model showed that under reduced atmospheric ozone concentrations, suppression of photosynthesis and leaf growth would be more severe during mid-sunnner (i . e. June) than would occur during the March to early May period, This results from smaller solar angles from the zenith and lower prevailing ozone concentrations prevalent during June. A validation test of the model was made with photosynthetic data obtained during a field study with R. patientia exposed to UV-B radiation corresponding to a 38 percent atmospheric ozone reduction (0.18 atm•cm when the sun was at 30° from the zenith). This validation test showed a reasonable correspondence between the measured and predicted photosynthetic rates. R. patientia was selected as the test species for this study because (1) it is reasonably sensitive to UV radiation as determined in preliminary studies evaluating approximately 20 native and agricultural plant species, (2) it is normally exposed to full sunlight in · its natural habitat, and (3) individual leaves are relatively long - lived (about 60 days) and are not normally shaded by other leaves of the same plant. Although this species probably represents one of the more sensitive plants to UV radiation, it would be this group of sensitive plants that would be initially affected under conditions of reduced atmospheric ozone. If more resistant plants with long-lived plant parts also accumulate UV radiation damage as was shown to occur in R. patientia, over sufficient periods of time even these species might be significantly impacted under conditions of reduced atmospheric ozone.

Long-distance dispersal of Rumex alpinus was studied in the Giant Mountain in the National Park. The invasion of R. alpinus is there kind of problem. The work builds on a thesis from year 2007 (20007 Červenková), in which was made the model of the invasion of R. alpinus in the area of the Giant Mountain. The measurements of the seeds spread take place at four localities, three of them were for measuring of water dispersal and one was for measuring of winter dispersal. Anemochory was measured using traps in the meadow up to a distance of 50 m. The seeds were dispersed by wind to a distance of 20 meters. Hydrochory was measured using a network's traps in the streams up to 100 m. The largest measured water dispersal was 100 m. Hydrochory therefore proved to be an important factor, which influenced the invasion of R. alpinus. The storms and flood had the great influence on the hydrochory and anemochory. The prediction exponential curves were compiled from the data about the wind dispersal. The curves express the spread to more than a measured distance. The field dispersion curves were compared with theoretical curves, which were used in the model of the invasion from 2007. It turned out that the theoretical curves overestimate the spread of R. alpinus by wind. The dispersion of seeds was underestimated in the...

<p>U ovoj doktorskoj disertaciji prikazani su rezultati istraživanja 15&nbsp;vrsta&nbsp; biljaka&nbsp; koje&nbsp; pripadaju&nbsp; rodovima <em>Rumex,&nbsp; Polygonum,&nbsp;Bistorta,&nbsp; Persicaria i&nbsp; Fagopyrum,</em>&nbsp; podfamilije&nbsp; Polygonoideae,&nbsp;familije&nbsp; Polygonaceae,&nbsp; sakupljenih&nbsp; na&nbsp; teritoriji&nbsp; centralnog&nbsp; i&nbsp;zapadnog &nbsp;Balkana u periodu od 2009-2011. godine. Sprovedena&nbsp;istraživanja&nbsp; su&nbsp; se&nbsp; odvijala&nbsp; u&nbsp; dva&nbsp; pravca:&nbsp; fitohemijska&nbsp; i&nbsp;biohemijsko-biolo&scaron;ka&nbsp; ispitivanja.&nbsp; Predmet&nbsp; analiza&nbsp; bili&nbsp; su&nbsp;ekstrakti&nbsp; herbi&nbsp; i&nbsp; rizoma&nbsp; ispitivanih&nbsp; biljaka.&nbsp; Fitohemijska&nbsp;ispitivanja&nbsp; obuhvatila&nbsp; su,&nbsp; pored&nbsp; spektrofotometrijskog&nbsp;određivanja&nbsp; ukupnih&nbsp; fenola,&nbsp; ukupnih&nbsp; flavonoida&nbsp; i&nbsp; ukupnih&nbsp;antrahinonskih jedinjenja, i određivanje sadržaja 51 komponente&nbsp;iz standardne sme&scaron;e različitih klasa fenolnih jedinjenja LC-MSMS&nbsp; metodom,&nbsp; odnosno &nbsp;hromatografsko&nbsp; profilisanje&nbsp; ekstrakata&nbsp;LC-DAD-MS&nbsp; metodom.&nbsp; Odabirom&nbsp; nekoliko&nbsp; različitih&nbsp; model&nbsp;sistema&nbsp; za&nbsp; merenje&nbsp; antioksidantne&nbsp; aktivnosti&nbsp; (neutralizacija&nbsp;DPPH&nbsp; radikala,&nbsp; redoks&nbsp; kapacitet&nbsp; -&nbsp; FRAP&nbsp; test,&nbsp; skevindžer&nbsp;aktivnost&nbsp; prema&nbsp; superoksidanjon&nbsp; radikalu,&nbsp; NO&nbsp; radikalu&nbsp; i&nbsp; OH&nbsp;radikalu,&nbsp; kao&nbsp; i&nbsp; inhibicija&nbsp; lipidne&nbsp; peroksidacije)&nbsp; procenjen&nbsp; je&nbsp;antioksidantni&nbsp; potencijal&nbsp; ekstrakata,&nbsp; dok&nbsp; je&nbsp; za&nbsp; procenu&nbsp; njihove&nbsp;antiinflamatorne&nbsp; aktivnosti&nbsp; kori&scaron;ćen&nbsp; potencijal&nbsp; inhibicije&nbsp;biosinteze medijatora inflamacije u humanim trombocitima (kao&nbsp;model&nbsp; sistemu).&nbsp; Mikrobiolo&scaron;ka&nbsp; ispitivanja&nbsp; su&nbsp; obuhvatila&nbsp;određivanje&nbsp; potencijala&nbsp; ovih&nbsp; vrsta&nbsp; u&nbsp; inhibiciji&nbsp; rasta&nbsp; serije&nbsp; gram&nbsp;pozitivnih i gram negativnih sojeva batkerija. Konačno, urađena&nbsp;je&nbsp; analiza&nbsp; korelacije&nbsp; hemijskog&nbsp; sastava,&nbsp; biolo&scaron;ke&nbsp; aktivnosti&nbsp; i&nbsp;pripadnosti taksonomskim grupama.</p> / <p>Phytochemical&nbsp; and&nbsp; biochemical&nbsp; analysis&nbsp; of&nbsp; herbal&nbsp; and&nbsp; root&nbsp;ethanol&nbsp; extracts&nbsp; of&nbsp; 15&nbsp; species&nbsp; belonging&nbsp; to&nbsp; different&nbsp; genera&nbsp;(<em>Rumex,&nbsp; Polygonum,&nbsp; Bistorta,&nbsp; Persicaria and&nbsp; Fagopyrum</em>)&nbsp; of&nbsp;subfamily&nbsp; Polygonoideae,&nbsp; was&nbsp; examined.&nbsp; Phytochemical&nbsp;characterization&nbsp; included&nbsp; spectrophotometric&nbsp; determination&nbsp; of&nbsp;total&nbsp; phenolic,&nbsp; total&nbsp; flavonoids&nbsp; and&nbsp; total&nbsp; anthraquinone&nbsp; contents,&nbsp;quantification&nbsp; of&nbsp; 51&nbsp; secondary&nbsp; metabolites&nbsp; by&nbsp; LC/MS/MS&nbsp;analysis&nbsp; and&nbsp; chromatographic&nbsp; fingerprinting by&nbsp; LC/DAD/MS&nbsp;technique,&nbsp; of&nbsp; prepared&nbsp; extracts.&nbsp; The&nbsp; antioxidant&nbsp; activity&nbsp; was&nbsp;evaluated&nbsp; by&nbsp; measuring&nbsp; ferric&nbsp; reducing&nbsp; ability&nbsp; (FRAP)&nbsp; of&nbsp; the&nbsp;extracts and their radical scavenging capacity towards DPPH, OH,&nbsp;NO and O₂^{&ndash;&nbsp;}radicals, and inhibition of lipid peroxidation). Antiinflammatory activity was evaluated by LC/MS/MS monitoring of&nbsp;selected&nbsp; metabolites&nbsp; (12-(S)-HHT,&nbsp; 12(S)-HETE,&nbsp; PGE_2&nbsp;,&nbsp; PGF_2&alpha;,&nbsp;and TXB₂) formed in cyclooxygenase and lipoxygenase pathways&nbsp;of arachidonic acid metabolism. Human platelets were used as a&nbsp;source&nbsp; of&nbsp; enzymes,&nbsp; while&nbsp; inflammation&nbsp; was&nbsp; induced&nbsp; by&nbsp;calcimycin. The antibacterial activity of prepared&nbsp; extracts against&nbsp;nine&nbsp; bacterial&nbsp; strains&nbsp; was&nbsp; evaluated&nbsp; by&nbsp; microtiter&nbsp; assay&nbsp; with&nbsp;resazurin as a colorimetric growth indicator.</p>

Titre de l'écran-titre (visionné le 16 janvier 2024) / La biodésinfection anaérobie du sol (BDA) est une alternative écologique à la fumigation des sols dans la culture du fraisier. Cette étude avait pour objectifs (1) d'évaluer la phytotoxicité de la BDA, (2) d'évaluer la phytotoxicité post-BDA, (3) de caractériser les profils d'acides gras volatils (AGVs) produits au cours de la BDA et (4) de déterminer la phytotoxicité et la fongitoxicité des AGVs. La BDA a été réalisée in vitro avec du sol contenant des graines de plantes adventices (oseille crépue, amarante de Powell); le sol ayant été amendé avec l'une ou l'autre des matières organiques (MO) suivantes: mélasse, drêche de brasserie, marc de pomme et résidus d'élagage de framboisiers. Par la suite, des graines d'avoine ou de navet fourrager ont été semées dans chaque sol traité et les concentrations en AGVs (acide acétique, butyrique, isobutyrique, propionique et isovalérique) ont été déterminées par HPLC. Les concentrations les plus élevées d'AGVs ont été observées dans les sols amendés en mélasse ou marc de pomme. La BDA réalisée avec la mélasse a provoqué l'effet phytotoxique le plus important tuant 100% des graines de plantes adventices. La BDA réalisée avec la mélasse ou le marc de pomme a montré la plus forte phytotoxicité post-BDA. Enfin, la phytotoxicité et la fongitoxicité des AGVs ont été évaluées en exposant les graines et le champignon Verticillium dahliae à différentes concentrations d'AGVs en solution ou sous forme de vapeur. Certains AGVs (en solution ou sous forme de vapeur) se sont avérés phytotoxiques. Tous les AGVs sous forme de vapeur se sont révélés fongitoxiques envers V. dahliae. Cette étude montre que la BDA a des effets phytotoxiques dont l'intensité varie selon la MO utilisée. Elle montre également que la MO utilisée influence les profils en AGVs produits au cours de la BDA dont certains sont phytotoxiques et fongitoxiques.

<p>&Scaron;tavelj (Rumex crispus, Polygonaceae) je vi&scaron;egodi&scaron;nja zeljasta biljka, koja predstavlja bogat izvor fenolnih komponenti. Iako se smatra invazivnim korovom, mlado li&scaron;će &scaron;tavelja je jestivo i često se koristi kao salata. Dalje, upotreba plodova &scaron;tavelja opisana je u srpskoj i turskoj narodnoj medicini u lečenju gastrointestinalnih tegoba. Cilj ovog rada bio je procena in vitro i in vivo antioksidantne/prooksidantne i citotoksične aktivnosti, i određivanje eventualnog in vitro antiinflamatornog efekta vodenog ekstrakta ploda Rumex crispus. Ukupan sadržaj flavonoida određen je spektrofotometrijskom metodom. Kvalifikacija i kvantifikacija flavonoida potvrđena je visokoefikasnom tečnom hromatografijom (HPLC). Antioksidantna aktivnost vodenog ekstrakta ploda &scaron;tavelja procenjena je na osnovu in vitro testova: Ferric-reducing antioxidant power (FRAP), sposobnosti ekstrakta da neutrali&scaron;e slobodne radikale NO&bull;, OH&bull; i DPPH&bull; i uticaja na lipidnu peroksidaciju u lipozomima. Citotoksičnost ispitivanog ekstrakta je određena in vitro na tumorskim ćelijskim linijama: humani karcinom cerviksa (HeLa), adenokarcinom (HT-29) i adenokarcinom dojke (MCF7). Takođe, moguća in vivo hepatoprotektivna i antioksidantna svojstva ekstrakta određena su kod oksidativnog stresa izazvanog CCl4 kod eksperimentalnih životinja. Pored toga, proverena je hipoteza u kojoj testiran ekstrakt pokazuje in vivo antiproliferativnu aktivnost kod Ehrlich-ovih (EAC) i Hepatoma AS30D ćelija, merenjem zapremine ascitesa, procenta vijabilnih ćelija i nivoa nekoliko antioksidantnih enzima. Optimizovan in vitro test za određivanje potencijala inhibicije ciklooksigenaze-1 (COX-1) i 12-lipooksigenaze (12-LOX) preduzet je u svrhu procene antiinflamatornog efekta vodenog ekstrakta ploda R. crispus. HPLC analiza otkrila je da je mikvelianin najdominantniji flavonoidni konstituent ekstrakta. Testirani ekstrakt pokazao je potencijalnu antioksidantnu aktivnost rezultujući velikom moći u neutralizaciji slobodnih radikala, i sposobno&scaron;ću da smanji lipidnu peroksidaciju u lipozomima. Rezultati su ukazali na tkivno-selektivnu citotoksičnost ekstrakta ploda R. crispus in vitro. Najizraženija antitumorska aktivnost primećena je prema HeLa i MCF7 ćelijskim linijama. Podaci sugeri&scaron;u da bi se ispitivani ekstrakt mogao smatrati potencijalnim in vivo hepatoprotektivnim i antioksidantnim agensom, sprečavajući oksidativna o&scaron;tećenja jetre. S druge strane, pomenuti ekstrakt može pokazati in vivo prooksidantna svojstva, uzrokujući oksidativni stres u maligno transformisanim EAC i AS30D ćelijama i smanjujući zapreminu ascitesa i udeo vijabilnih ćelija, u poređenju sa kontrolnom grupom. Promene u aktivnosti antioksidantnih enzima su verovatno posledica indukovanog oksidativnog stresa u EAC i AS30D ćelijama, naročito kod pretretiranih životinja. Vodeni ekstrakt ploda &scaron;tavelja pokazao je COX-1, kao i 12-LOX inhibitornu aktivnost, navodeći da bi ispitivani ekstrakt mogao biti antiinflamatorni agens. Vodeni ekstrakt ploda R. crispus ima potencijalnu antioksidantnu, citotoksičnu i antiinflamatornu aktivnost. Ispoljavanje prooksidantnih svojstava predstavlja mogući mehanizam antiproliferativnog efekta ekstrakta.</p> / <p>Curly dock (Rumex crispus, Polygonaceae) is a wild perennial herbaceous plant, which products are described as a rich source of phenolic compounds. Apart from being considered a seriously invasive weed, young leaves of curly dock are edible and often used as salad. Furthermore, the use of its fruits has been described in Serbian and Turkish traditional medicine against stomach complaints. The objectives of this study were to evaluate in vitro and in vivo antioxidant/prooxidant and cytotoxic activities, and to determine an eventual in vitro anti-inflammatory effect of the aqueous extract of Rumex crispus fruits. Total flavonoid content was determined by spectrophotometric method. Qualification and quantification of flavonoids were confirmed using High performance liquid chromatography (HPLC). The aqueous extract of curly dock fruits was evaluated for its antioxidant activity by in vitro assays for Ferric-reducing antioxidant power (FRAP), NO&bull;, OH&bull; and DPPH&bull;-free radical scavenging activities and the influence on lipid peroxidation in liposomes. The cytotoxicity of tested extract was examined in vitro in human cervix carcinoma (HeLa), colon adenocarcinoma (HT-29) and breast adenocarcinoma (MCF7). Also, the potential in vivo hepatoprotective and antioxidant properties of investigated extract were determined on CCl4-induced oxidative stress in experimental animals. Furthermore, the hypothesis that the examined extract might show in vivo antiproliferative activity in Ehrlich carcinoma (EAC) and Hepatoma AS30D cells was tested by measuring volume of ascites, percentage of viable cells and level of several antioxidant enzymes. The optimized in vitro test for determination of cyclooxygenase-1 (COX-1) and 12-lipoxygenase (12-LOX) inhibition potency was undertaken in order to estimate an anti-inflammatory effect of aqueous extract of R. crispus fruits. HPLC analysis revealed miquelianin as the most abundant flavonoid constituent of the extract. The tested extract might have an antioxidant activity resulting in scavenging of free radicals and ability to decrease lipid peroxidation in liposomes. The results could indicate tissue-selective cytotoxicity of R. crispus fruit extract in vitro. The most prominent antitumor activity was observed towards HeLa and MCF7 cell lines. The data suggested that investigated extract may be considered as potential in vivo hepatoprotective and antioxidant agent due to prevention of the liver injuries induced by oxidative damage. On the other hand, mentioned extract could exhibit in vivo prooxidant property, causing the oxidative stress in malignant transformed EAC and AS30D cells and reducing volume of ascites and percentage of viable cells, in comparison with control group. Changes in activities of antioxidant enzymes might be the results of induced oxidative stress in EAC and AS30D cells, especially in the pretreated animals. The aqueous extract of curly dock fruits showed COX-1, as well as 12-LOX inhibitory activity, suggesting that tested extract might be an anti-inflammatory agent. It could be concluded that aqueous fruit extract of R. crispus might have antioxidant, cytotoxic and anti-inflammatory activities. The prooxidant properties of examined extract could be the mechanism of potential antiproliferative effect of extract.</p>