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41.
Menkis A Burokienė D Gaitnieks T Uotila A Johannesson H Rosling A Finlay RD Stenlid J Vasaitis R 《FEMS microbiology ecology》2012,81(2):438-445
The aim of this study was to assess belowground occurrence, persistence and possible impact of the biocontrol agent Phlebiopsis gigantea (Fr.) Jülich on soil fungi. Sampling of soil and roots of Picea abies (L.) H. Karst. was carried out at 12 P. gigantea-treated and five nontreated control sites representing 1- to 60-month-old clear-cuts and thinned forest sites in Finland and Latvia. The 454-sequencing of ITS rRNA from fine roots, humus and mineral soil resulted in 8626 high-quality fungal sequences. Phlebiopsis gigantea represented 1.3% of all fungal sequences and was found in 14 treated and nontreated sites and in all three substrates. In different substrates, the relative abundance of P. gigantea at stump treatment sites either did not differ significantly or was significantly lower than in nontreated controls. No significant correlation was found between the time elapsed since the tree harvesting and/or application of the biocontrol and abundance of P. gigantea in different substrates. In conclusion, the results demonstrate that P. gigantea occasionally occurs belowground in forest ecosystems but that stump treatment with the biocontrol agent has little or no impact on occurrence and persistence of P. gigantea belowground, and consequently no significant impact on soil fungi. 相似文献
42.
Risk preferences drive much of human decision making including investment, career and health choices and many more. Thus, understanding the determinants of risk preferences refines our understanding of choice in a broad array of environments. We assess the relationship between risk preferences, prenatal exposure to sex hormones and gender for a sample of Ladinos, which is an ethnic group comprising 62.86% of the population of Guatemala. Prenatal exposure to sex hormones has organizational effects on brain development, and has been shown to partially explain risk preferences for Caucasians. We measure prenatal exposure to sex hormones using the ratio of the length of the index finger to the length of the ring finger (2D:4D), which is negatively (positively) correlated with prenatal exposure to testosterone (estrogen). We find that Ladino males are less risk averse than Ladino females, and that Ladino males have lower 2D:4D ratios than Ladino females on both hands. We find that the 2D:4D ratio does not explain risk preferences for Ladinos. This is true for both genders, and both hands. Our results highlight the importance of exploring the behavioral significance of 2D:4D in non-Caucasian racial groups. 相似文献
43.
Root-Associated Fungi of Rosa rugosa Grown on the Frontal Dunes of the Baltic Sea Coast in Lithuania
The aim of the present study was to assess fungal communities associated with fine living roots of Rosa rugosa Thunb grown on the frontal dunes of Curonian Spit at the Baltic Sea coast in Lithuania. The roots of R. rugosa were sampled at five sites (Nida, Preila, Pervalka, Juodkrante and Smiltyne) situated at a distance ca. 5–15 km from each other. Direct amplification, cloning and sequencing of fungal ITS rRNA from the fine roots resulted in 134 high-quality sequences, representing 31 fungal taxa among which saprotrophs and endophytes Mycena sp. (14.2 %), Tumularia sp. (14.2 %), Penicillium spinulosum (11.9 %) and Cadophora malorum (9.0 %) were most common. Arbuscular mycorrhizal fungi including Entrophospora baltica (0.7 %) and Rhizophagus irregularis (0.7 %) and potentially root pathogenic fungi—Ceratobasidium sp. (4.5 %), Fusarium oxysporum (3.0 %), Fusarium culmorum (0.7 %) and Ilyonectria crassa (0.7 %)—were also detected at low proportions. In conclusion, the results demonstrated that the fine roots of R. rugosa are inhabited by various groups of fungi. Although saprotrophs and endophytes were dominant, the detection of arbuscular mycorrhizal fungi indicated that these may be important for mineral nutrition of R. rugosa established on dry and poor fertility coastal dunes. 相似文献
44.
Jenzsch M Gnoth S Kleinschmidt M Simutis R Lübbert A 《Bioprocess and biosystems engineering》2006,29(5-6):315-321
In industry Escherichia coli is the preferred host system for the heterologous biosynthesis of therapeutic proteins that do not need posttranslational modifications. In this report, the development of a robust high-cell-density fed-batch procedure for the efficient production of a therapeutic hormone is described. The strategy is to guide the process along a predefined profile of the total biomass that was derived from a given specific growth rate profile. This profile might have been built upon experience or derived from numerical process optimization. A surprisingly simple adaptive procedure correcting for deviations from the desired path was developed. In this way the batch-to-batch reproducibility can be drastically improved as compared to the process control strategies typically applied in industry. This applies not only to the biomass but, as the results clearly show, to the product titer also. 相似文献
45.
The objectives of this study were to investigate impact of stump and slash removal on growth and mycorrhization of Picea abies seedlings outplanted on a forest clear-cut. Four non-replicated site preparation treatments included: (1) mounding (M), (2)
removal of stumps (K), (3) mounding and removal of logging slash (HM) and (4) removal of logging slash and stumps (HK). Results
showed that height increment of the seedlings was highest in K and lowest in M after the third growing season, and similar
pattern remained after the fourth season. Ectomycorrhizal (ECM) colonisation of seedling roots was highest in M (96.6%) and
lowest in K (72.3%), and even in HK (76.0%) and HM (76.3%). Morphotyping and sequencing of internal transcribed spacer of
fungal ribosomal DNA revealed a total of 13 ECM species. Among those, Thelephora terrestris and Cenococcum geophilum were the most common, found on 27.4% and 26.3% of roots, respectively. The rest of species colonised 26.6% of roots. Richness
of ECM species was highest in M (10 species) and lowest in K (three species). Consequently, stump and slash removal from clear-felled
sites had a positive effect on growth of outplanted spruce seedlings, but negative effect on their mycorrhization. This suggests
that altered soil conditions due to site disturbance by stump and slash removal might be more favourable for tree growth than
more abundant mycorrhization of their root systems in less disturbed soil. 相似文献
46.
Ylva Persson Rimvydas Vasaitis Bo L?ngstr?m Petter ?hrn Katarina Ihrmark Jan Stenlid 《Microbial ecology》2009,58(3):651-659
The bark beetle Ips typographus has different hibernation environments, under the bark of standing trees or in the forest litter, which is likely to affect
the beetle-associated fungal flora. We isolated fungi from beetles, standing I. typographus-attacked trees, and forest litter below the attacked trees. Fungal identification was done using cultural and molecular methods.
The results of the two methods in detecting fungal species were compared. Fungal communities associated with I. typographus differed considerably depending on the hibernation environment. In addition to seven taxa of known ophiostomoid I. typographus-associated fungi, we detected 18 ascomycetes and anamorphic fungi, five wood-decaying basidomycetes, 11 yeasts, and four zygomycetes.
Of those, 14 fungal taxa were detected exclusively from beetles that hibernated under bark, and six taxa were detected exclusively
from beetles hibernating in forest litter. The spruce pathogen, Ceratocystis polonica, was detected occasionally in bark, while another spruce pathogen, Grosmannia europhioides, was detected more often from beetles hibernating under the bark as compared to litter. The identification method had a significant
impact on which taxa were detected. Rapidly growing fungal taxa, e.g. Penicillium, Trichoderma, and Ophiostoma, dominated pure culture isolations; while yeasts dominated the communities detected using molecular methods. The study also
demonstrated low frequencies of tree pathogenic fungi carried by I. typographus during its outbreaks and that the beetle does not require them to successfully attack and kill trees. 相似文献
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48.
Magdalena Niedziałkowska Kris J. Hundertmark Bogumiła Jędrzejewska Krzysztof Niedziałkowski Vadim E. Sidorovich Marcin Górny Rauno Veeroja Erling J. Solberg Sauli Laaksonen Håkan Sand Vyacheslav A. Solovyev Maryna Shkvyria Juha Tiainen Innokentiy M. Okhlopkov Rimvydas Juškaitis Gundega Done Vadim A. Borodulin Evgenii A. Tulandin Włodzimierz Jędrzejewski 《Journal of Biogeography》2014,41(11):2173-2184
49.
Rimvydas Juškaitis 《Acta theriologica》2014,59(2):311-316
In the period 2000–2012, 38.3 % of 950 marked overwintered hazel dormice (Muscardinus avellanarius) were not recaptured at a study site in Lithuania in autumn. As adult dormice are sedentary, it is presumed that those dormice not recaptured died between late April and August. The highest total number of dormice captured for the last time was recorded in May and the lowest in August. The total summer mortality was significantly higher in females (42.5 %) than in males (34.6 %), but it did not depend on dormouse age or body weight. Tawny owl (Strix aluco) is the main known dormouse predator in Lithuania, and likely, it has the highest impact on summer mortality of M. avellanarius. Over the years, the total summer mortality of adult dormice ranged from 27 % to 52 %. The increased summer mortality resulted in decreased total dormouse population density and particularly decreased density of adult females in summer. Decreased densities led to more intensive breeding in the dormouse population, specifically breeding by young-of-the-year females, a pattern that is not common for this species. The number of breeding cases by young-of-the-year females was inversely related to the density of adult overwintered females in summer and to the number of breeding cases of these females. Breeding by young-of-the-year females was the main factor in the restoration of decreased population density in summer. Lithuanian populations of M. avellanarius are unique in their high proportion of breeding cases by young-of-the-year females amongst all populations investigated in the entire species distributional range. 相似文献
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