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101.
Barbara Piwowarczyk Krzysztof Tokarz Wojciech Makowski Aneta Łukasiewicz 《Acta Physiologiae Plantarum》2017,39(4):96
Grass pea (Lathyrus sativus L.) is a legume crop known from its tolerance to various abiotic stresses, especially drought. In this study, we investigated: (1) the response of grass pea seedlings to osmotic stress generated in vitro by polyethylene glycol (PEG); (2) potential drought acclimatization mechanisms of two polish grass pea cultivars. Grass pea seeds of two cultivars were sown on media containing different PEG concentrations (0, 5.5, 11.0 mM) and cultivated for 14 days in controlled conditions. Plants’ dry matter increased under osmotic stress (regardless of PEG concentration). In turn, the highest dose of PEG caused a reduction in seedling growth in both cultivars. Furthermore, PEG caused the peroxidase activity increase in whole seedlings and catalase (CAT) activity in roots. However, differences between cultivars were noted in: CAT activity in shoots; while phenols and anthocyanin content as well as electrolyte leakage in shoots and roots. In turn, in both tested genotypes, accumulation of proline increased in shoots under osmotic stress. Obtained results indicate that the examined plants, although belonging to the same species, differ in acclimatization processes leading to elevated tolerance to osmotic stress. 相似文献
102.
Olena Kudlai Aneta Kostadinova Eric E. Pulis Vasyl V. Tkach 《Systematic parasitology》2017,94(1):21-33
Three new psilostomid genera, Byrdtrema n. g., Longisaccus n. g. and Macracetabulum n. g., each with a single species, are described from ducks, Aix sponsa (L.) and Bucephala albeola (L.) in North America. Byrdtrema n. g. and Macracetabulum n. g. possess a bipartite seminal vesicle and share this character with four psilostomid genera, Grysoma Byrd, Bogitsh & Maples, 1961, Neopsilotrema Kudlai, Pulis, Kostadinova & Tkach, 2016, Psilostomum Looss, 1899 and Psilotornus Byrd & Prestwood, 1969. Byrdtrema n. g. differs from Macracetabulum n. g. in the shape of the body (elongate vs elongate-oval); the position of the ventral sucker (in first third of body vs just pre-equatorial); the shorter forebody; as well as in the smaller size of the eggs in relation to body length. Both new genera differ from (i) Grysoma by the nature of the vitellarium (large, compact follicles with small vitelline cells vs weakly defined follicles with large vitelline cells, respectively) and the smaller size of the eggs in relation to body length; (ii) Psilostomum in the posterior extend of the cirrus-sac in relation to ventral sucker (slightly posterior vs more posterior), the location of the genital pore (at the level of oesophagus vs just postbifurcal), the shorter length of uterine and longer post-testicular fields in relation to body length, and the anterior limits of vitellarium (at the level of ventral sucker vs posterior to ventral sucker); (iii) Psilotornus by the presence of a muscular pharynx (vs absent or rudimentary) and the location of the cirrus-sac (antero-dorsal to ventral sucker or more posterior vs entirely anterior to ventral sucker) and ovary (in hindbody vs in forebody). Byrdtrema n. g. differs from Neopsilotrema in the shape of the body (elongate vs subspherical to elongate-oval) and ventral sucker (elongate-oval vs subspherical to transversely oval), the shorter forebody and smaller eggs in relation to body length. Macracetabulum n. g. differs from Neopsilotrema by the shape of the ventral sucker (elongate-oval vs subspherical to transversely oval), the anterior limits of vitellarium (level of middle of ventral sucker vs level of intestinal bifurcation or anterior testis); and the slightly smaller size of eggs in relation to body length. Among the psilostomid genera, Longisaccus n. g. shows close affinities to Psilochasmus Lühe, 1909 in the presence of the long cirrus-sac and tubular internal seminal vesicle but can be clearly distinguished from the latter by the absence of the retractile tail-like process. In combination with molecular data, the above differences justify the recognition of three new genera. A key to the genera of the Psilostomidae is provided. 相似文献
103.
Aneta Arct Joanna Sudyka Edyta Podmokła Szymon M. Drobniak Lars Gustafsson Mariusz Cichoń 《Evolutionary ecology》2017,31(5):803-814
Understanding the relation between genetic variation and fitness remains a key question in evolutionary biology. Although heterozygosity has been reported to correlate with many fitness-related traits, the strength of the heterozygosity–fitness correlations (HFCs) is usually weak and it is still difficult to assess the generality of these associations in natural populations. It has been suggested that HFCs may become meaningful only under particular environmental conditions. Moreover, existing evidence suggests that HFCs may also differ between sexes. The aim of this study was to investigate correlations between heterozygosity in neutral markers (microsatellites) and fitness-related traits in a natural population of blue tits (Cyanistes caeruleus). Additionally, we tested whether sex and environmental conditions may influence the magnitude and direction of HFCs. We found a positive relationship between heterozygosity and body mass of 14 days post-hatching nestlings, but only among females. Our results suggest that the correlation between heterozygosity and nestling body mass observed among female offspring could be attributed to within-brood effects. We failed to find any evidence that environmental conditions as simulated by brood size manipulation affect HFCs. 相似文献
104.
Długołecka A Cieśliński H Turkiewicz M Białkowska AM Kur J 《Protein expression and purification》2008,62(2):179-184
Recently we described identification and characterization of GDSL esterase EstA from psychrotrophic bacterium Pseudoalteromonas sp. 643A. Attempts to obtain heterologous overexpression of this enzyme in Escherichia coli system were not satisfactory. The EstA protein was expressed as inclusion bodies, most of that were inactive after purification step, and the recovery of esterolytic activity was very low after refolding. Based on the sequence analysis we found that the esterase EstA gene is clustered with three genes encoding components of ABC transport system. These genes, designated abc1, abc2, and abc3 encode an ATP-binding protein (ABC1) and two permease proteins (ABC2 and ABC3). In present study, to obtain larger amounts of the active cold-adapted EstA esterase from Pseudoalteromonas sp. 643A, we designed a two-plasmid E. coli expression system where the gene encoding EstA enzyme was cloned into pET30b(+) expression vector and three genes encoding components of ABC transport system were cloned into pACYC-pBAD vector. It was shown that the created expression system was useful for extracellular production of active EstA enzyme which was purified from the culture medium. In the presence of all the three transporter proteins the secretion of EstA was at the highest level. When one or two of these components were missing, EstA secretion was also possible, but not so effective. It indicates that ABC2 and ABC3 proteins of Pseudoalteromonas sp. 643A could be replaced with their homologous proteins of E. coli. 相似文献
105.
Selected airborne allergenic fungal spores and meteorological factors in Szczecin,Poland, 2004–2006 总被引:2,自引:1,他引:1
Airborne fungal spore concentrations in Szczecin, Poland, were studied between 2004 and 2006 with the objective of determining
a seasonal variation in the concentrations of selected fungal spore types in relation to meteorological parameters. The presence
of spores of five taxa, namely, Cladosporium, Ganoderma, Alternaria, Leptosphaeria and Didymella, was recorded using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers during the summer,
with the highest concentrations recorded mainly in June, July and August. The peak concentrations of two of the studied spore
types, Ganoderma and Alternaria, occurred in August, while the concentrations of Cladosporium, Leptosphaeria and Didymella spores were the highest in July. Multiple regression analysis was performed for three fungal seasons—2004, 2005 and 2006.
Spore concentration was found to be positively correlated with the minimum temperature. For some spore types, there was also
a significant correlation between concentrations, relative humidity and rain. 相似文献
106.
Influence of alternating temperature preculture on cryopreservation results for potato shoot tips 总被引:1,自引:0,他引:1
Kaczmarczyk A Shvachko N Lupysheva Y Hajirezaei MR Keller ER 《Plant cell reports》2008,27(9):1551-1558
Cryopreservation is the most suitable long-term storage method for genetic resources of vegetatively maintained crops like potato. In the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) the DMSO droplet method is applied, and so far more than 1000 accessions are cryopreserved with an average regeneration rate of 58%. New experiments with four potato accessions using alternating temperatures (22/8 degrees C day/night temperature, 8 h photoperiod, 7 d) prior to cryopreservation showed improved regeneration. The influence of this preculture on the shoot tips was studied for two wild, frost resistant species Solanum acaule and S. demissum and for two cultivated, frost sensitive potatoes S. tuberosum 'Désirée' and 'King Edward'. Comparison of liquid and solid media after cryopreservation showed improved regeneration on solid media with higher regeneration percentages, less callus formation and better plantlet structure. In comparative analyses biochemical factors like soluble sugars, starch, and amino acid concentrations were measured. Shoot tips after constant and after alternating temperature preculture were analyzed. Total concentrations of soluble sugars (glucose, fructose, and sucrose) were higher for all accessions after the alternating temperature preculture, which could be the reason for improved cryopreservation results. 相似文献
107.
Isabel Blasco-Costa David I. Gibson Juan Antonio Balbuena Juan Antonio Raga Aneta Kostadinova 《Systematic parasitology》2009,73(2):107-133
The status of the nominal species of Haploporus Looss, 1902 and Lecithobotrys Looss, 1902 is re-assessed by means of a comparative morphological study based on newly collected specimens from the western
Mediterranean, the re-examination of museum material and a critical evaluation of published data. H. benedeni (Stossich, 1887) (type-species) is described and H. lateralis Looss, 1902 is considered to be its junior synonym. Additional data are given for H. pseudoindicus Rekharani & Madhavi, 1985, H. spinosus Machida, 1996 and H. magnisaccus Machida, 1996. Species parasitising Valamugil spp. from the Indo-West Pacific region, H. indicus Rekharani & Madhavi, 1985, H. spinosus, H. magnisaccus, H. mugilis Liu & Yang, 2002 and H. muscolosaccus Machida, 2003, are considered incertae sedis with respect to their generic affiliation. H. pacificus (Manter, 1963) (syn. Neohaploporus pacificus Manter, 1963), H. pseudoindicus and H. musculosaccus are designated as species inquirendae and H. lossii Al-Bassel, 1990 is considered to be a nomen nudum. Lecithobotrys putrescens Looss, 1902 is described based on newly collected material from Liza spp. Pseudolecithobotrys n. g. is erected to accommodate Lecithobotrys stomachicola Machida, 1996, as P. stomachicola (Machida, 1996) n. comb., from the North Pacific. L. aegyptiacus Hassan, El-Aziz, Khidr & Abu Samak, 1990 is considered to be a synonym of Saccocoelium tensum Looss, 1902, and L. brisbanensis (Martin, 1974) (syn. Paralecithobotrys
brisbanensis Martin, 1974), L. vitellosus Sharma & Gupta, 1970 and L. suezcanali Nisreen Ezz El-Dien, Abdel-Rahman, El-Gawady, Imam & Fahmy, 1990 are regarded as species inquirendae. New generic diagnoses are presented for both Haploporus and Lecithobotrys.
相似文献
Isabel Blasco-CostaEmail: |
108.
M. Parczewski M. Leszczyszyn-Pynka M. Kaczmarczyk G. Adler A. Bińczak-Kuleta B. Łoniewska A. Boroń-Kaczmarska A. Ciechanowicz 《Journal of applied genetics》2009,50(2):159-166
Genetic susceptibility to HIV infection was previously proven to be influenced by some chemokine receptor polymorphisms clustering
on chromosome 3p21. Here the influence of 5 genetic variants was studied: Δ32CCR5, G(-2459)ACCR5, G190ACCR2, G744ACX3CR1 and C838TCX3CR1. They were screened in a cohort of 168 HIV-1 positive adults [HIV(+) group] and 151 newborns [control group] from northwestern
Poland. PCR-RFLP was performed to screen for the variants (except for A32CCR5 polymorphism, where PCR fragment size was sufficient to identify the alleles) and then electrophoresed on agarose gel to
determine fragment size. Distribution of genotypes and alleles was not significantly different between the groups except for
theCCR5 polymorphisms, with the A32 allele and the (-2459)ACCR5 allele more frequent among neonates than in the HIV(+) group. No Δ32/Δ32 homozygotes were found in the HIV(+) group, but
16.1% were Δ32/wt heterozygotes. In the control group, 1.3% were Δ32/Δ32 homozygotes and 26.0% were Δ32/wt heterozygotes.
Linkage between the chemokine polymorphisms was calculated using the most informative loci for haplotype reconstruction. Haplotypes
containing Δ32 CCR5,190GCCR2 and 744ACX3CR1 were found to be significantly more common in the control group. This suggests an association between these haplotypes and
resistance to HIV-1 infection. 相似文献
109.
Aneta D. Petelska Monika Naumowicz Zbigniew A. Figaszewski 《The Journal of membrane biology》2009,228(2):71-77
We measured the interfacial tension of lipid membranes composed of ceramide-cholesterol, ceramide-sphingomyelin, and sphingomyelin-cholesterol.
The membrane components formed 1:1 complexes. Interfacial tension measurements were used to determine the membrane surface
concentration A
3−1, the membrane interfacial tension γ3, and the stability constant K. 相似文献
110.
Krzysztof Mikołajczak Anetta Kuczyńska Paweł Krajewski Aneta Sawikowska Maria Surma Piotr Ogrodowicz Tadeusz Adamski Karolina Krystkowiak Andrzej G. Górny Michał Kempa Iwona Szarejko Justyna Guzy-Wróbelska Kornelia Gudyś 《Journal of applied genetics》2017,58(1):23-35
High-yielding capacity of the modern barley varieties is mostly dependent on the sources of semi-dwarfness associated with the sdw1/denso locus. The objective of the study was to identify quantitative trait loci (QTLs) associated with the plant height and yield potential of barley recombinant inbred lines (RILs) grown under various soil moisture regimes. The plant material was developed from a hybrid between the Maresi (European cv.) and CamB (Syrian cv.). A total of 103 QTLs affecting analysed traits were detected and 36 of them showed stable effects over environments. In total, ten QTLs were found to be significant only under water shortage conditions. Nine QTLs affecting the length of main stem were detected on 2H-6H chromosomes. In four of the detected QTLs, alleles contributed by Maresi had negative effects on that trait, the most significant being the QLSt-3H.1-1 in the 3H.1 linkage group. The close linkage between QTLs identified around the sdw1/denso locus, with positive alleles contributed by Maresi, indicates that the semi-dwarf cv. Maresi could serve as a donor of favourable traits resulting in grain yield improvement, also under water scarcity. Molecular analyses revealed that the Syrian cv. also contributed alleles which increased the yield potential. Available barley resources of genomic annotations were employed to the biological interpretation of detected QTLs. This approach revealed 26 over-represented Gene Ontology terms. In the projected support intervals of QGWSl-5H.3-2 and QLSt-5H.3 on the chromosome 5H, four genes annotated to ‘response to stress’ were found. It suggests that these QTL-regions may be involved in a response of plant to a wide range of environmental disturbances. 相似文献