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431.
It is recommended that browse should be an important part of diets for browsing and intermediate feeding type ruminants. However, provision of browse in winter time is problematic for many zoos located in the temperate climate. Drying or freezing of branches are commonly practiced solutions to this problem, but ensiling of tree leaves could also be an attractive option. The aim of this study was to determine the effect of drying and ensiling of different tree leaves on preference of their intake by nyala antelope (Tragelaphus angasii), an intermediate feeding type ruminant. A study was conducted on five nyala fed a standard diet (meadow hay, dehydrated chopped lucerne and limited concentrates) before and during the study. Preference of intake of five feeds was tested: dried maple (A. platanoides), oak (Q. robur), willow (S. alba), and ensiled maple and lime (T. cordata) leaves. Each day two tested feeds were offered to each animal. After 4 h of presentation, feed refusals were weighed and preference ratio for each tested feed and animal was calculated. Then, preferences were ranked using a pairwise comparison chart. Dried maple and oak leaves were preferred more than other leaves whereas ensiled lime leaves were the least preferred. On the other hand, ensiled and dried maple leaves were equally preferred. Results of this study showed that palatability of ensiled tree leaves should not be a concern when feeding nyala, and likely also other browsing or intermediate feeding type ruminants, but palatability of silage may depend on the species of tree. 相似文献
432.
Arkadiusz Nowak Sylwia Nowak Marcin Nobis Agnieszka Nobis 《Central European Journal of Biology》2014,9(4):444-460
The paper presents the results of phytosociological research conducted on the vegetation of rock clefts and ledges in the Pamir-Alai Mountains (Tajikistan, Middle Asia). During the field studies, done in 2010–2012, 101 phytosociological relevés were taken. Plant species were recorded according to the Braun-Blanquet cover-abundance scale. Communities of calcareous rock clefts and ledges with small soil amounts from several ranges (Zeravshan Mts, Hissar Mts, Hazratishokh Mts, Darvaz Mts, Rushan Mts and Vanch Mts), inhabiting mainly the alpine and subnival zone, have been described. A synopsis of the rock communities of the Pamir-Alai is proposed. In the examined vegetation plots 77 vascular plant and 6 moss species were noted. The most frequent were: Achoriphragma pinnatifidum, Artemisia rutifolia, Asperula albiflora, Campanula incanescens, C. lehmanniana, Parietaria judaica, Pentanema albertoregelia, Poa relaxa and Stipa zeravshanica among vascular plants and Brachythecium albicans and Bryum caespiticum among mosses. Most of them are narrow endemics of Tajikistan or Middle Asia. The collected material presents most of the variability among the phytocoenoses of large crevices and rock ledges in limestone massifs in the alpine and subnival zones. As a result of field research and numerical analyses, 7 associations have been distinguished: Achoriphragmetum pinnatifidi, Asperulo albiflorae-Stipetum zeravshanicae, Inuletum glaucae, Paraquilegietum anemonoidis, Pentanemetum albertoregeliae, Rhinactinidietum popovii and Saussureaetum ovatae. The distinctiveness of habitat and species composition of Middle Asiatic rock communities makes it necessary to distinguish a new suballiance, Pentanemenion albertoregeliae, within the Asperulo albiflorae-Poion relaxae alliance. The main factors determining the species composition of classified associations seem to be the elevation above sea level and exposition. Alpine rock communities are one of the most unique and interesting plant formations in the moutainous areas of Pamir-Alai. Despite not being species-rich they often harbour many specialists adapted to harsh and extreme environments, especially in areas of Mediterranean-like climate. 相似文献
433.
Anabella Aguilera Javier Alegria Zufia Laura Bas Conn Leandra Gurlit Sylwia Śliwińska-Wilczewska Gracjana Budzałek Daniel Lundin Jarone Pinhassi Catherine Legrand Hanna Farnelid 《Environmental microbiology》2023,25(9):1674-1695
Cluster 5 picocyanobacteria significantly contribute to primary productivity in aquatic ecosystems. Estuarine populations are highly diverse and consist of many co-occurring strains, but their physiology remains largely understudied. In this study, we characterized 17 novel estuarine picocyanobacterial strains. Phylogenetic analysis of the 16S rRNA and pigment genes (cpcB and cpeBA) uncovered multiple estuarine and freshwater-related clusters and pigment types. Assays with five representative strains (three phycocyanin rich and two phycoerythrin rich) under temperature (10–30°C), light (10–190 μmol photons m−2 s−1), and salinity (2–14 PSU) gradients revealed distinct growth optima and tolerance, indicating that genetic variability was accompanied by physiological diversity. Adaptability to environmental conditions was associated with differential pigment content and photosynthetic performance. Amplicon sequence variants at a coastal and an offshore station linked population dynamics with phylogenetic clusters, supporting that strains isolated in this study represent key ecotypes within the Baltic Sea picocyanobacterial community. The functional diversity found within strains with the same pigment type suggests that understanding estuarine picocyanobacterial ecology requires analysis beyond the phycocyanin and phycoerythrin divide. This new knowledge of the environmental preferences in estuarine picocyanobacteria is important for understanding and evaluating productivity in current and future ecosystems. 相似文献
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435.
Tomasz M. Stępkowski Sylwia Męczyńska-Wielgosz Marcin Kruszewski 《Cellular and molecular neurobiology》2017,37(6):1055-1066
Perturbations in the transport of mitochondria and their quality control in neuronal cells underlie many types of neurological pathologies, whereas systems enabling convenient analysis of mitochondria behavior in cellular models of neurodegenerative diseases are limited. In this study, we present a modified version of lund human mesencephalic cells, mitoLUHMES, expressing GFP and mitochondrially targeted DsRed2 fluorescent proteins, intended for in vitro analysis of mitochondria trafficking by real-time fluorescence microscopy. This cell line can be easily differentiated into neuronal phenotype and allows us to observe movements of single mitochondria in single cells grown in high-density cultures. We quantified the perturbations in mitochondria morphology and dynamics in cells treated with model neurotoxins: carbonyl cyanide m-chlorophenylhydrazone and 6-hydroxydopamine. For the first time we filmed the processes of fission, fusion, pausing, and reversal of mitochondria movement direction in LUHMES cells. We present a detailed analysis of mitochondria length, velocity, and frequency of movement for static, anterograde, and retrograde motile mitochondria. The observed neurotoxin treatment-mediated decreases in morphological and kinetic parameters of mitochondria provide foundation for the future studies exploiting mitoLUHMES as a new model for neurobiology. 相似文献
436.
Beverly J. Agtuca Sylwia A. Stopka Sterling Evans Laith Samarah Yang Liu Dong Xu Minviluz G. Stacey David W. Koppenaal Ljiljana Paa‐Toli Christopher R. Anderton Akos Vertes Gary Stacey 《The Plant journal : for cell and molecular biology》2020,103(5):1937-1958
The establishment of the nitrogen‐fixing symbiosis between soybean and Bradyrhizobium japonicum is a complex process. To document the changes in plant metabolism as a result of symbiosis, we utilized laser ablation electrospray ionization‐mass spectrometry (LAESI‐MS) for in situ metabolic profiling of wild‐type nodules, nodules infected with a B. japonicum nifH mutant unable to fix nitrogen, nodules doubly infected by both strains, and nodules formed on plants mutated in the stearoyl‐acyl carrier protein desaturase (sacpd‐c) gene, which were previously shown to have an altered nodule ultrastructure. The results showed that the relative abundance of fatty acids, purines, and lipids was significantly changed in response to the symbiosis. The nifH mutant nodules had elevated levels of jasmonic acid, correlating with signs of nitrogen deprivation. Nodules resulting from the mixed inoculant displayed similar, overlapping metabolic distributions within the sectors of effective (fix+) and ineffective (nifH mutant, fix?) endosymbionts. These data are inconsistent with the notion that plant sanctioning is cell autonomous. Nodules lacking sacpd‐c displayed an elevation of soyasaponins and organic acids in the central necrotic regions. The present study demonstrates the utility of LAESI‐MS for high‐throughput screening of plant phenotypes. Overall, nodules disrupted in the symbiosis were elevated in metabolites related to plant defense. 相似文献
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438.
Impact of rhizobacterial inoculants on plant growth and enzyme activities in soil treated with contaminated bottom sediments 总被引:1,自引:0,他引:1
Sylwia Siebielec Magdalena Urbaniak Bożena Smreczak Emilia Grzęda Anna Wyrwicka 《International journal of phytoremediation》2019,21(4):325-333
The impact of contaminated bottom sediments on plant growth and soil enzyme activities was evaluated in a greenhouse pot study. The sediments were moderately contaminated with zinc and heavily contaminated with polycyclic aromatic hydrocarbons and polychlorinated dibenzo-p-dioxins and furans. The sediments were mixed with soil and planted with either Festuca arundinacea or Tagetes patula. The capacity of two rhizobacterial strains (Massilia niastensis P87 and Streptomyces costaricanus RP92), previously isolated from contaminated soils, to improve plant growth under the chemical stress was tested. Application of sediments to soil was severely phytotoxic to T. patula and mildly to F. arundinacea. On the other hand, the addition of sediments enhanced the soil enzymatic activity. Inoculation with both bacterial strains significantly increased shoot (up to 2.4-fold) and root (up to 3.4-fold) biomass of T. patula. The study revealed that the selected plant growth-promoting bacterial strains were able to alleviate phytotoxicity of bottom sediments to T. patula resulting from the complex character of the contamination. 相似文献