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Wheat straw is the major crop residue in European countries which makes it the most promising material for bioconversion into biofuels. However, cellulose and hemicellulose are protected with lignin, so delignification is an inevitable phase in lignocellulose processing. The organisms predominantly responsible for its degradation are white-rot fungi and among them Trametes species represent promising degraders due to a well-developed ligninolytic enzyme system. Although numerous studies have confirmed that low molecular weight compounds can induce the production and activity of ligninolytic enzymes it is not clear how this reflects on the extent of delignification. The aim of the study was to assess the capacity of p-anisidine and veratryl alcohol to induce the production and activity of Mn-oxidizing peroxidases and laccases, and wheat straw delignification by six Trametes species. Significant inter- and intraspecific variations in activity and features of these enzymes were found, as well as differences in the potential of lignocellulose degradation in the presence or absence of inducers. Differences in the catalytic properties of synthesized enzyme isoforms strongly affected lignin degradation. Apart from enhanced lignin degradation, the addition of p-anisidine could significantly improve the selectivity of wheat straw ligninolysis, which was especially evident for T. hirsuta strains.

Vrste roda Mercurialis su se pokazale kao atraktivan objekat za raznovrsna ekološka, genetička i istraţivanja u evolucionoj biologiji biljaka. Šumski prosinac, Mercurialis perennis L., je višegodišnja zeljasta anemofilna i dvodoma vrsta, karakteristična za primarna ili manje narušena šumska staništa. Analiza populacija ove vrste sa različitih nadmorskih visina pruţila je mogućnost da se na relativno malom geografskom prostoru istraţi uticaj velikog raspona variranja ekoloških faktora na morfološke karakteristike i reproduktivnu alokaciju (RA) kod pripadnika različitih polova, kao i na brojčani odnos polova u populaciji. Istraţivanje je obuhvatilo populacije sa 14 lokaliteta u Srbiji, koje su uzorkovane u periodu 2006–2009. Statistički značajno odstupanje od pretpostavljenog ravnoteţnog odnosa polova ustanovljeno je u 69,5% populacionih uzoraka. Broj uzoraka sa neravnoteţnim odnosom polova varirao je meĎu godinama, a u većini istraţenih populacija neravnoteţa je bila u korist muških biljaka. Neravnoteţa u korist muških biljaka ustanovljena je i u istraţivanjima na drugim populacijama ove vrste, a ovakav obrazac neravnoteţe polova se smatra uobičajenim za višegodišnje dvodome biljke. Indeks polnog dimorfizma je kod većine analiziranih osobina imao male do umerne vrednosti, dok su izrazito i dosledno dimorfne bile one osobine koje su direktno povezane sa reprodukcijom – broj cvetova i masa cvasti. Smer polnog dimorfizma razlikuje se kod ovih osobina. Muški pol produkuje više cvetova, što ukazuje na pojačanu intraseksualnu selekciju u muškom polu za veću produkciju polena. S druge strane, masa ţenskih cvasti je višestruko veća od mase muških cvasti, što se preslikava i u veću reproduktivnu alokaciju ţenskih jedinki. U ţenskom polu je detektovan i obrazac smanjenja ulaganja u reprodukciju sa povećanjem nadmorske visine na kojoj biljka raste. Analize polnog dimorfizma u visini biljke pokazale su da je u većini populacionih uzoraka muški pol viši, što se uklapa u pretposta, The plant species of genus Mercurialis are very attractive object for various ecological, genetical and evolutionary researches. Dog’s mercury, Mercurialis perennis L., is a perennial anemophilous and dioecious herb, which usually grows in old and undisturbed forests. The analyses of populations of dog’s mercury from various altitudes gave us opportunity to investigate the effect of great environmental variation on morphological traits, reproductive allocation in different sexes, as well as on sex ratios in populations. This research included populations from 14 localities in Serbia sampled in 2006–2009. Statistically significant bias in sex ratio was found in 69.5% of population samples. Number of samples with biased sex ratio varied among years, and the majority of samples were male-biased. The male-biased populations of dog’s mercury were found elsewhere, and this pattern of bias is regarded to as the common one in dioecious perennials. Sexual dimorphism index for greater part of analysed traits had small to moderate values, while reproductive traits (number of flowers, mass of inflorescences) were markedly and consistently dimorphic. The range and direction of dimorphism differed in these reproductive traits. Males produced more flowers, and this information indicates pronounced intrasexual selection in males for greater pollen production. On the other hand, mass of female inflorescences was manifold bigger than mass of male inflorescences, and female reproductive allocation was bigger in a similar manner. In females, we also found pattern of decrease in reproductive allocation with the increase of altitude. The analyses of sexual dimorphism in plant size showed that males were the higher sex in majority of population samples. This is in agreement with pollen-dispersal hypothesis...

Vrste roda Mercurialis su se pokazale kao atraktivan objekat za raznovrsna ekološka, genetička i istraţivanja u evolucionoj biologiji biljaka. Šumski prosinac, Mercurialis perennis L., je višegodišnja zeljasta anemofilna i dvodoma vrsta, karakteristična za primarna ili manje narušena šumska staništa. Analiza populacija ove vrste sa različitih nadmorskih visina pruţila je mogućnost da se na relativno malom geografskom prostoru istraţi uticaj velikog raspona variranja ekoloških faktora na morfološke karakteristike i reproduktivnu alokaciju (RA) kod pripadnika različitih polova, kao i na brojčani odnos polova u populaciji. Istraţivanje je obuhvatilo populacije sa 14 lokaliteta u Srbiji, koje su uzorkovane u periodu 2006–2009. Statistički značajno odstupanje od pretpostavljenog ravnoteţnog odnosa polova ustanovljeno je u 69,5% populacionih uzoraka. Broj uzoraka sa neravnoteţnim odnosom polova varirao je meĎu godinama, a u većini istraţenih populacija neravnoteţa je bila u korist muških biljaka. Neravnoteţa u korist muških biljaka ustanovljena je i u istraţivanjima na drugim populacijama ove vrste, a ovakav obrazac neravnoteţe polova se smatra uobičajenim za višegodišnje dvodome biljke. Indeks polnog dimorfizma je kod većine analiziranih osobina imao male do umerne vrednosti, dok su izrazito i dosledno dimorfne bile one osobine koje su direktno povezane sa reprodukcijom – broj cvetova i masa cvasti. Smer polnog dimorfizma razlikuje se kod ovih osobina. Muški pol produkuje više cvetova, što ukazuje na pojačanu intraseksualnu selekciju u muškom polu za veću produkciju polena. S druge strane, masa ţenskih cvasti je višestruko veća od mase muških cvasti, što se preslikava i u veću reproduktivnu alokaciju ţenskih jedinki. U ţenskom polu je detektovan i obrazac smanjenja ulaganja u reprodukciju sa povećanjem nadmorske visine na kojoj biljka raste. Analize polnog dimorfizma u visini biljke pokazale su da je u većini populacionih uzoraka muški pol viši, što se uklapa u pretposta, The plant species of genus Mercurialis are very attractive object for various ecological, genetical and evolutionary researches. Dog’s mercury, Mercurialis perennis L., is a perennial anemophilous and dioecious herb, which usually grows in old and undisturbed forests. The analyses of populations of dog’s mercury from various altitudes gave us opportunity to investigate the effect of great environmental variation on morphological traits, reproductive allocation in different sexes, as well as on sex ratios in populations. This research included populations from 14 localities in Serbia sampled in 2006–2009. Statistically significant bias in sex ratio was found in 69.5% of population samples. Number of samples with biased sex ratio varied among years, and the majority of samples were male-biased. The male-biased populations of dog’s mercury were found elsewhere, and this pattern of bias is regarded to as the common one in dioecious perennials. Sexual dimorphism index for greater part of analysed traits had small to moderate values, while reproductive traits (number of flowers, mass of inflorescences) were markedly and consistently dimorphic. The range and direction of dimorphism differed in these reproductive traits. Males produced more flowers, and this information indicates pronounced intrasexual selection in males for greater pollen production. On the other hand, mass of female inflorescences was manifold bigger than mass of male inflorescences, and female reproductive allocation was bigger in a similar manner. In females, we also found pattern of decrease in reproductive allocation with the increase of altitude. The analyses of sexual dimorphism in plant size showed that males were the higher sex in majority of population samples. This is in agreement with pollen-dispersal hypothesis. The statistical regression models of spatial and temporal variation of sex ratio and reproductive allocation were created by generalized least squares method. Among these models, the b