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The Fissidentaceae is one of the moss families with the genus Fissidens. A species of Fissidens viz., F. pokhrensis has been collected from the Neeliyarkottam sacred grove of Kannur District, which is a new record to the moss flora of Kerala. Sacred groves remain neglected in the study of bryoflora.

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Hyophila involuta (Hook) Jaeg., a sample collected from a natural population in the Biological Garden, Obafemi Awolowo University, Nigeria, was sorted into non-sporophytic and sporophytic gametophytes. This was with a view to investigating the possible influence of sporophyte emergence on the bioactive constituents and the antimicrobial potentials of the moss plant. Aqueous extracts of each of the non-sporophytic and the sporophytic gametophyte samples were prepared, and each was subjected to qualitative and quantitative phytochemical screening, gas chromatography-mass spectrometry (GC-MS) analyses, and antimicrobial potentials tests on selected bacteria and fungi following standard procedures. The results showed both extracts testing positive for alkaloids, cardiac glycosides, saponins, and steroids. Quantitatively, alkaloids and cardiac glycosides concentrations were higher in the non-sporophytic than in the sporophytic gametophytes. Nevertheless, the saponins content was higher in sporophytic gametophytes. GC-MS analyses revealed 40 and 46 bioactive compounds in the non-sporophytic and the sporophytic gametophyte samples respectively. The most prominent compound was 1, 13-tetradecadiene (13.62%) in the non-sporophytic gametophyte but cycloheptasiloxane tetradecamethyl- (13.78%) in the sporophytic game-tophyte. Furthermore, the sporophytic gametophyte extract inhibited the growth of Escherichia coli, Pseudomonas aeruginosa, and Candida pseudotropicalis while the non-sporophytic gametophyte extract only inhibited the growth of P. aeruginosa at a minimum inhibitory concentration of 40 mg/mL except for C. pseudotropicalis (20 mg/mL). This study, therefore, provided insight for investigating the medicinal values of bryophytes and concluded that the emergence of sporophytes on gametophytes of a bryophyte species can vary significantly the synthesis of its biologically active compounds and its antimicrobial activity.

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Xanthoria ectaneoides, usually recognised by its secondary sublobules, is circumscribed in a strict sense using spore size and a molecular phylogeny based on ITS-sequences. The species, earlier considered a synonym of X. aureola, forms a subclade with X. coomae and the new species X. pylyporlykii, described here, whereas X. aureola is positioned in the Xanthoria calcicola subclade. The new species X. pylyporlykii is characterised by a combination of characters typical either for Xanthoria ectaneoides or X. coomae.

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New Records for the Bryophyte Flora of Vietnam, 5

Epihyllous liverworts of Tam Đảo Mountains, Vietnam

Acta Botanica Hungarica
Author:
T. Pócs

In November 1998, guided by Prof. Trấn Ninh we revisited the Tam Đảo mountain range, extensively researched by him before. Since than it was converted into a National Park, with areas stretching to three provinces, Vĩnh Phúc, Thái Nguyên, and Tuyên Quang. The previous collections indicated that many more novelties can be expected from there. As a result, we collected 38 epiphyllous liverwort species. Among these 6 were new to the flora of Vietnam: Cololejeunea fructu-marginata, C. papillosa, C. spathulifolia, Colura bisvoluta, Lejeunea dipterota and Microlejeunea sechuanensis. One species is new to science: Cololejeunea dinhensis. Furthermore, Cololejeunea rotundilobula proved to be a new synonym of Cololejeunea sigmoidea.

Open access
Acta Botanica Hungarica
Authors:
M. Taheri
,
J. Gherekhloo
,
S. Sohrabi
,
A. Siahmarguee
, and
S. Hassanpour-bourkheili

Sea barley is weedy grass in agricultural landscapes and infrastructure habitats (roads, railroads, etc.) in Golestan province (the northern part of Iran). This study investigated the germination of sea barley in response to temperature, water potentials, salinity, pH levels, waterlogging, heat stress and also seedling emergence in response to burial depth. Results showed that sea barley seeds germinated over a wide range of temperatures from 5 to 35 °C, with the highest germination at 25 °C. Seed germination was rapidly reduced with increasing osmotic potential so that germination declined by 36% at –0.2 MPa. This was also the case for the salinity stress, and germination declined by 30% at 40 mM NaCl. Seed germination was the highest (> 65%) in 6 to 7 pHs and no germination was observed at alkali levels. Heat stress completely inhibited the germination of seeds at all tested temperatures and durations. Sea barley seed germination was higher than 50% after being waterlogged for 45 days, and some germination (12%) still occurred 60 days after waterlogging. The highest seedling growth occurred at 1–2 cm soil depth and was negligible at ≥5 cm soil depths. The results of this study indicate that deep tillage or flamethrower may be good options to mitigate the negative impacts of this weed.

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Two new associations of natural acid Norway spruce communities (the order Piceetalia abietis Pawłowski ex Pawłowski et al. 1928 nom. corr.) from Slovakia are introduced: Solidagini virgaureae-Piceetum abietis and Parido quadrifoliae-Piceetum abietis. Their original relevés and floristical characteristics are published as well as their differentiation against the most common acid Norway spruce community in the Central Europe – the association LophozioPiceetum abietis Volk in Braun-Blanquet et al. 1939 (syn.: Vaccinio myrtilli-Piceetum Šoltés 1976, Calamagrostio villosae-Piceetum auct. non Schlüter 1966). The distribution of hitherto known phytocoenological relevés of the two considered communities Solidagini virgaureaePiceetum and Parido quadrifoliae-Piceetum and the field experience indicate that their distribution within the Western Carpathians is bound to high mountain ranges (hochgebirge mountain ranges).

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Using medicinal plants for healthcare practices in indigenous communities presents a chance to discover natural remedies. This study aims to provide a detailed account of the ethnoveterinary knowledge of medicinal plants utilized for therapeutic purposes. From December 2020 to December 2021, a field investigation was carried out within the Oulad Heriz tribes. Two hundred local farmers were interviewed using open-ended, semi-structured discussions, free listing and focus groups. A total of one hundred medicinal plants belonging to 87 genera and 33 families were discovered to be employed for ethnoveterinary purposes. Rosmarinus officinalis L. was the most frequently utilized ethnoveterinary plant species in the study area (70 citations). Leaves are shown to be the most commonly employed plant parts (55%). However, digestive disorders were the most often mentioned ailment (33 medicinal plants, 599 citations), and most herbal medicines were made by infusion (46.2%). According to the current investigation findings, local farmers in Oulad Heriz have continuous knowledge of ethnoveterinary plants. This ethnoveterinary medicinal heritage needs to be incorporated with contemporary medicine to use plants and their products as potentially viable medications for various cattle illnesses.

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Abstract

Infectious diseases pose a formidable global challenge, compounded by the emergence of antimicrobial resistance. Consequently, researchers are actively exploring novel antimicrobial compounds as potential solutions. This endeavor underscores the pivotal role of methods employed for screening and evaluating antimicrobial activity—a critical step in discovery and characterization of antimicrobial agents. While traditional techniques such as well-diffusion, disk-diffusion, and broth-dilution are commonly utilized in antimicrobial assays, they may encounter limitations concerning reproducibility and speed. Additionally, a diverse array of antimicrobial assays including cross-streaking, poisoned-food, co-culture, time-kill kinetics, resazurin assay, bioautography, etc., are routinely employed in antimicrobial evaluations. Advanced techniques such as flow-cytometry, impedance analysis, and bioluminescent technique may offer rapid and sensitive results, providing deeper insights into the impact of antimicrobials on cellular integrity. However, their higher cost and limited accessibility in certain laboratory settings may present challenges. This article provides a comprehensive overview of assays designed to characterize antimicrobial activity, elucidating their underlying principles, protocols, advantages, and limitations. The primary objective is to enhance understanding of the methodologies designed for evaluating antimicrobial agents in our relentless battle against infectious diseases. By selecting the appropriate antimicrobial testing method, researchers can discern suitable conditions and streamline the identification of effective antimicrobial agents.

Open access

Abstract

The Giant Elm Bracket (Rigidoporus ulmarius) is a widely-distributed necrotrophic polypore species that causes white heart rot in deciduous trees. Despite its recognition as one of the largest species known for forming basidiomata, this perennial polypore had not been documented in Hungary. However, in recent years, two specimens macroscopically resembling this species were collected on old horse chestnut (Aesculus hippocastanum) trees from two different places in Hungary by amateur mycologists. In this study, subsequent morphological and molecular-genetic analyses of these fungal samples confirmed their identity as R. ulmarius. This study represents the first documented occurrence of this plant pathogenic polypore species in Hungary.

Open access
Acta Phytopathologica et Entomologica Hungarica
Authors:
Marianna I. Zhukovskaya
,
Inna V. Grushevaya
,
Alexander A. Miltsen
,
Oksana G. Selitskaya
,
Anna V. Shchenikova
,
Andrei N. Frolov
, and
Miklós Tóth

Abstract

The European corn borer, Ostrinia nubilalis (Hubner), relies on multimodal sensory information to find food, mates, mating and ovipositional grounds. Successful phytosanitary monitoring demands for the bait for the field traps to obtain the most reliable representation of pest abundance. Attraction to light and blend of key components of host plant odor, was tested both in the laboratory and field conditions. Ultraviolet light, which was the most effective in the wind tunnel experiments, was further tested in the field alone and in combination with bisexual lure. Bisexual lure, being attractive in the lab, as well as in the field, did not improve responses to ultraviolet in both experimental designs. All three baits attracted significantly more females than males in the field. Wind tunnel experiments revealed that ultraviolet elicited the shortest response latencies either alone or paired with the odor bait. The lack of synergistic effect between attractive light and odor stimuli is an important issue for pest monitoring. The possible reasons for the observed lack of synergy are the hierarchy of behavioral responses to different stimuli or the intensities of both stimuli are critically important for attractivity of combined stimulus and differ from separately presented ones.

Open access