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Haloxylon aphyllum is a significant species adapted to salinity conditions and plays an important role in stabilising soil, providing forage, and serving as a source of firewood for residents. In this study, the genetic diversity of four populations of H. aphyllum in Iran was examined using four primers to assess genetic diversity, which produced a total of 41 bands. The AMOVA test showed that the studied populations differed in their genetic content. Specifically, 46% of genetic variability occurred within populations, while 54% arose between populations, indicating a high degree of genetic variation among H. aphyllum populations. The Mantel test presented a significant correlation between genetic distance and geographic distance. Additionally, the STRUCTURE analysis presented comprehensive information on the genetic structure of the studied H. aphyllum populations. The presence of genetic diversity and heterozygosity among H. aphyllum populations suggests local adaptation among populations, which may be due to the heterogeneity of environmental factors such as soil moisture and nutrients that create genetic heterogeneity.

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A new parasitic lichenicolous fungus Knudsenia, with the type species, K. flavoparmeliarum, growing on the thallus of the corticolous lichen Flavoparmelia caperata in subalpine and alpine regions of Central Himalaya (Uttarakhand, India) is described, illustrated, and compared with other morphologically similar lichenicolous fungi. It is characterised by having inconspicuous galls; stromatic ascomata with sterile brownish black to black tissue which is K+ majenta, N–, I–; hymenial gel K/I–; exciple evident; paraphyses simple to sparsely branched, apically not pigmented; asci bitunicate, elongate, clavate to subcylindrical with an indistinct ocular chamber with a very short stalk, 8-spored, K/I+ reddish brown; ascospores hyaline, spherical to ellipsoid at maturity, simple to rarely 1-pseudoseptate [(9.0–)9.5–10.5–11.5(–12.0) × (1.0–)1.2–1.5–2.0(–2.5) µm], I–, perispore absent. Since the species lacks molecular data, hence, it was tentatively placed in the family Planistromellaceae pending further studies.

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New Records for the Liverwort and Hornwort Flora of Vietnam, 3

Epiphyllous collections of Pierre Tixier in the Natural History Museum, Paris

Acta Botanica Hungarica
Author:
T. Pócs

Pierre Tixier deposited a large amount of bryophyte collections, including epiphylls, in the Cryptogamic Herbarium of the Natural History Museum in Paris (PC). A very large part of his valuable epiphyllous specimens collected between 1957 and 1965 in the southern half of Vietnam remained unidentified. Based on study of a small portion of these collections, 44 species are reported including six new to the country (Dendroceros subplanus, Ceratolejeunea singapurensis, Cheilolejeunea rigidula, Cololejeunea angulata, C. stephanii and Thysananthus aculeatus). Ceratolejeunea and Dendroceros are genera new to Vietnam.

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Bellevalia Lapeyr. (Asparagaceae) underwent numerous changes in infrageneric classification based on morphological characteristics between 1854 and 1980. In 1939, a comprehensive classification was proposed, based on the morphological features of the flowers and leaves of 45 species. This classification, which was unique at the time, divided the genus into four sections and six subsections. In 2021, a phylogenetic study was conducted on 14 Bellevalia species using four plastid genes. The study led to a revised infrageneric classification determined by the presence or absence of cilia at the leaf margins. In this study, morphological characteristics, particularly the presence of cilia at the leaf margins, were assessed for of 40 Bellevalia species and categorised according to the recent infrageneric classification. The results showed that 13 species exhibited glabrous or smooth leaf margins while 27 displayed non-glabrous leaf margins. Three types of cilia were observed in non-glabrous species: a) ribbon-shape, b) turbinate or conical, and c) papilla. Notably, the species with glabrous leaf margins were exclusively found in the Irano-Turanian region, whereas non-glabrous species were distributed throughout the Irano-Turanian, Mediterranean and Saharo-Sindian regions.

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In this study, palynological characteristics of 23 specimens of Helichrysum Mill., representing 12 Iranian species were investigated. We evaluated pollen grains (25 per specimens) and tested them by 15 qualitative and quantitative characteristics using Scanning Electron Microscopy (SEM). Pollen grain descriptions of most species were presented for the first time in the world. The pollen grains were tricolporate, radially symmetrical and isopolar in all examined samples. They were small, and rarely medium in size. The polar outline view (amb) was the same among the species. The overall views of pollen grains were prolate-spheroidal, oblate-spheroidal, subprolate, prolate and spheroidal. However, the more abundant type was prolate-spheroidal. The exine sculpture was echinate, and tectum is perforate. The ANOVA test revealed a significant variation (P < 0.001) for all the quantitative characteristics. In PCA analysis, the colpus length, width, and length/width ratio traits, polar and equatorial axes length, were the most variable features and some species were characterised by these characters. Results indicated that a few qualitative characteristics such as polar outline view and exine sculpture lack taxonomic importance via their stability among species. Also, the palynological traits had enough potential to separate the taxonomic boundaries of H. rubicundum and H. globiferum, but approximately the species clustering pattern did not agree with Flora Iranica.

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Forest regeneration is a natural process of forest resource reclamation through production of young ones (saplings and seedlings). Tree species show variable regeneration potential in different associations and response to natural and man-made factors. Banj oak (Quercus leucotrichophora A. Camus), one of the important forest forming tree species in western montane Himalaya, is facing regeneration failure in different locations. The present study attempted to assess the population structure and regeneration of Q. leucotrichophora and associated tree species in five different stands (sites) of a less explored region (Tehri Garhwal, Uttarakhand, Western Himalaya). To investigate the phytosociological attributes, ten sampling quadrats (400 m2) were laid in random sampling manner in each forest stand for surveying tree layer, 2 sub-quadrats (25 m2) for saplings, and 5 sub-quadrats (1 m2) for seedlings in each sampling quadrat. Among the studied forest stands, tree species richness ranged 8 to 11 (8.8±1.3), total stem density (ind/ha) 750 to 950 (846±85.6), and total basal area (m2/ha) 18.68 to 29.18 (24.1±3.9). Based on abundance data the banj oak showed ‘good’ regeneration statuses (density of seedling > saplings > adult trees) in all forests. The distribution of adult tree individuals into different size classes (DBH classes) also indicate ‘good’ regeneration pattern (higher density in lower size classes and gradual decrease in density towards higher classes or forming a reverse J-shaped pattern). However, majority of the banj oak associated species (e.g. Prunus cerasoides, Pyrus pashia, Rhododendron arboreum, etc.) represented ‘fair’ regeneration statuses (seedlings > or ≤ saplings ≤ adult trees). Overall, the results of this study shed light on the positive prospects for Q. leucotrichophora regeneration and the importance of sustainable coexistence between human communities and these vital forest ecosystems.

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Abstract

The fungal genus Fusarium encompasses a diverse group of species responsible for synthesizing mycotoxins, particularly deoxynivalenol, fumonisin, and zearalenone and inducing Fusarium head blight in wheat. The research was undertaken over a period of two consecutive growing seasons (2020 and 2021) on the premises and facilities of the Hungarian University of Agriculture and Life Sciences (MATE). The objective of this study was to investigate the impact of growing season, nitrogen fertilization, and wheat variety on Fusarium infection as well as mycotoxin contamination in wheat kernel. Zearalenone was absent throughout the course of the two growing seasons, whereas deoxynivalenol was found solely in 2020. The findings demonstrate that nitrogen fertilization failed to exhibit a statistically significant impact on both Fusarium infection and mycotoxin production. The impact of wheat variety on Fusarium infection and deoxynivalenol was not found to be statistically significant. However, it exerted a significant effect on fumonisin production. The growing season exerted a statistically significant impact on the incidence of Fusarium infection and the ensuing contamination with mycotoxins, attributable to augmented precipitation levels in 2021 compared to 2020, specifically during the flowering period when the spike of wheat is highly susceptible to Fusarium infection.

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Abstract

The acreage of English walnut (Juglans regia L.) is constantly expanding in Hungary, due to the favorable climatic conditions and economic importance. Last years, serious damage was reported from several orchards with high percentage of rotted, moldy kernels. The aim of this research was to identify the pathogens at different growth stages. Fungi were cultured from the spotty, shriveled and rotted kernels, and monosporic isolates were identified based on morphological characters and molecular markers (ITS region and tef1 locus sequences). Botryosphaeria dothidea and Diaporthe eres were identified in high proportion from symptomatic kernels. These species were also isolated from different parts of walnut trees in different seasons. D. eres was detected in a high proportion from asymptomatic buds in March, while the presence of both species was observed in symptomatic husks with Overnight Freezing-Incubation Technique (ONFIT) in June. Their optimal growth temperature defined to be between 20–25 °C, and the growth of D. eres isolates was completely inhibited at 35 °C.

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Abstract

One of the major and yet unsolved threats for viticulture is the group of vascular fungal infections, the so-called grapevine trunk diseases. Besides their latent nature and the enormous number of associated pathogens, their control is also hampered by the lack of effective fungicides, directing growing attention toward the use of biocontrol agents. In the present study the isolation, identification, and characterization of a bacterial strain are presented, showing biocontrol potential against some main causal agents of grapevine trunk diseases. The strain was isolated from the wood of an asymptomatic grapevine and selected for the fungicidal activity against the pathogen Phaeomoniella chlamydospora. According to 16S rDNA, gyrA, and gyrB sequences, the isolate belongs to Bacillus velezensis species. Confrontation tests with the bacterium or with its fermentation broth further revealed growth inhibition and fungicide activity against Botryosphaeria dothidea, Eutypa lata and Diaporthe ampelina pathogens. Fractionation of the bacterial culture filtrate suggests that the antifungal agents secreted by the B. velezenzis isolate are mainly lipoproteins. Phytotoxicity tests were also carried out with the isolate, showing no harmful effects on grapevine foliar disks.

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Abstract

Soluble dietary fibre (SDF) is well recognised for its remarkable effectiveness in promoting human health. This study utilised response surface methodology to evaluate the optimal conditions required to extract SDF (U-SDF) from Lentinula edodes via the ultrasonic-assisted hot-water method, and evaluated the hypolipidemic effects and anti-inflammatory effects of U-SDF. The optimal extraction conditions for U-SDF were ultrasonic power of 182 W, extraction time of 2 h, extraction temperature of 81 °C, and solid-liquid ratio of 1:24 (g mL−1). Under these conditions, the extraction rate of U-SDF reached 8.08%. U-SDF treatment significantly improved liver and kidney indices in diabetic mice, markedly reduced the levels of plasma triglycerides (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and significantly increased the level of high-density lipoprotein-cholesterol (HDL-C) in a dose-dependent manner. U-SDF also improved adipose tissue injury in diabetic mice, significantly decreased the levels of cytokines interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumour necrosis factor-α (TNF-α), and alleviated inflammation of the abdominal aorta. In conclusion, U-SDF from L. edodes is an excellent source of dietary fibres, which exhibit good hypolipidemic and anti-inflammatory activities, suggesting potential applications as a functional additive in diverse food products.

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