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1.
Věra Holubová-Jechová 《Folia Geobotanica》1973,8(2):209-218
The species of three genera—Sporoschisma Berk. etBr.,Sporoschismopsis Hol.-Jech. etHennebert andCatenularia Grove are treated in this paper from Czechoslovakia:Sporoschisma juvenile Boudier,S. mirabile Berk. etBr.,Sporoschismopsis moravica Hol.-Jech. etHennebert andCatenularia cuneiformis (Richon) Mason. The studied fungi produce the conidia in basipetal succession, endogenously or subendogenously, quite internally in large phialides or only inside open swollen collarettes. 相似文献
2.
The use of subfossil cladocerans is rare for understanding environmental, cultural and archaeological developments of lakes in Europe. In 2007, we collected a 12-m long sediment core from Lake Schalkenmehrener Maar (SMM), Germany for the analyses of subfossil cladocerans. Dating of core was based on tephrochronology, radiocarbon and pollen stratigraphy. Pollen-based chronostratigraphy indicated a decline of species richness and abundance of chydorids during the Lateglacial (ca.14500?cal?yr?bp) with dominant cold preferring taxa Acroperus harpae Baird and Alona affinis Leydig. During the early B?lling, the abundance of cladocerans increased commensurate with growth of birch (Betula L.) and pine (Pinus L.) trees. Except a spike of Bosmina coregoni Baird during the Younger Dryas, cladoceran assemblages remained stable from the B?lling to the mid-Atlantic period. During the Neolithic (ca. 4300?bc), the abundance of B. coregoni increased sharply with reciprocal decrease in Daphnia. However, as soon as Daphnia was dominant (ca. 4250?bc), a reciprocal decline in abundance of B. coregoni occurred. The mid-Holocene change in cladoceran abundance coincided with the use of hardwood forest. This situation ended at ca. 4000?bc and remained unchanged throughout the Neolithic and Bronze Age (ca. 3000?C1200?bc). Low Daphnia abundance indicated reduced water quality in the Hunsr??ck-Eifel culture (ca. 800?bc). A spike of B. coregoni at ca. ad 150 indicates construction of the Roman Villa Rustica and extensive farming. However, reoccurrence of Daphnia at ca. ad 470 indicates the retreat of the Romans from the Eifel region. From the early Frankish rule (ca. ad 500) to the Medieval period (ca. ad 1500), species richness reduced but abundance of B. coregoni increased indicating a switch in lake ecosystem. The loss of species richness and the lack of precise evidence of the human activity in the region in the past have impeded the restoration of the ecosystem of the Lake SMM. 相似文献
3.
Nishanth Kumar C. Mohandas Bala Nambisan D. R. Soban Kumar Ravi S. Lankalapalli 《World journal of microbiology & biotechnology》2013,29(2):355-364
Entomopathogenic nematodes (EPN) are well-known as biological control agents and are found to have associated bacteria which can produce a wide range of bioactive secondary metabolites. We report herewith isolation of six proline containing cyclic dipeptides cyclo(d-Pro-l-Leu), cyclo(l-Pro-l-Met), cyclo(d-Pro-l-Phe), cyclo(l-Pro-l-Phe), cyclo(l-Pro-l-Tyr) and cyclo(l-Pro-d-Tyr) from ethyl acetate extract of the Luria Broth (LB) cell free culture filtrate of Bacillus sp. strain N associated with a new EPN Rhabditis sp. from sweet potato weevil grubs collected from Central Tuber Crops Research Institute farm. Antimicrobial studies of these 2,5-diketopiperazines (DKPs) against both medicinally and agriculturally important bacterium and fungi showed potent inhibitory values in the range of μg/mL. Cyclic dipeptides showed significantly higher activity than the commercial fungicide bavistin against agriculturally important fungi, viz., Fusarium oxysporum, Rhizoctonia solani, and Pencillium expansum. The highest activity of 2 μg/mL by cyclo(l-Pro-l-Phe) was recorded against P. expansum, a plant pathogen responsible for causing post harvest decay of stored apples and oranges. To our knowledge, this is the first report on the isolation of these DKPs from Rhabditis EPN bacterial strain Bacillus sp. 相似文献
4.
Marta Szal Mirosława Kupryjanowicz Mariusz Wyczółkowski Wojciech Tylmann 《Vegetation History and Archaeobotany》2014,23(4):419-437
Pollen, non-pollen palynomorphs, charcoal and geochemical analyses of sediments from Lake Sal?t (NE Poland) were used to reconstruct vegetation changes related to the activity of the West Balt tribes during the Iron Age, in the period between the second half of the 7th century bc and the beginning of the 10th century ad. We distinguished five phases of human impact on environment. Woodland clearing around the studied lake started at the end of the 7th century bc. The most characteristic feature of this area during the whole Iron Age was a very high representation of semi-natural Betula woodlands, which was probably linked to a shifting agriculture. This type of land use lasted for over 1,500 years, until the second half of the 9th century ad. The greatest reduction in Betula woodlands took place between cal. years 650 and 450 bc. Its regeneration took place after ca. ad 830 when human activity decreased. 相似文献
5.
Elena Venir Manuela Del Torre Vincenzo Cunsolo Rosaria Saletti Rita Musetti Mara Lucia Stecchini 《Archives of microbiology》2014,196(2):79-85
The l-alanine mediated germination of food isolated Bacillus cereus DSA 1 spores, which lacked an intact exosporium, increased in the presence of d-cycloserine (DCS), which is an alanine racemase (Alr) inhibitor, reflecting the activity of the Alr enzyme, capable of converting l-alanine to the germination inhibitor d-alanine. Proteomic analysis of the alkaline extracts of the spore proteins, which include exosporium and coat proteins, confirmed that Alr was present in the B. cereus DSA 1 spores and matched to that encoded by B. cereus ATCC 14579, whose spore germination was strongly affected by the block of conversion of l- to d-alanine. Unlike ATCC 14579 spores, l-alanine germination of B. cereus DSA 1 spores was not affected by the preincubation with DCS, suggesting a lack of restriction in the reactant accessibility. 相似文献
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James Innes Jeffrey Blackford Ian Simmons 《Vegetation History and Archaeobotany》2010,19(5-6):439-452
Pollen, micro-charcoal and non-pollen palynomorph (NPP) data from the mid Holocene Ulmus decline and the preceding millennium have provided evidence of repeated fire disturbance of the upland woodland at Bluewath Beck Head, on the North York Moors in northeast England. Woodland disturbance coincides with the Ulmus decline, which at several similar upland sites in northern England is dated to ca. 4800 uncal b.p. (ca. 5550 cal b.p.), and so to the early Neolithic period. Two fire events occur within a cycle of disturbance and regeneration between about 6100 (ca. 6950 cal b.p.) and 5700 b.p. (ca. 6475 cal b.p.), placing them in the later stages of the Late Mesolithic hunter-gatherer occupation of the upland and near the start of the transition to early Neolithic agricultural economies. Increased Melampyrum and Corylus pollen percentages characterise the post-fire vegetation response. These disturbances probably resulted from human activity, suggesting that fire was an integral part of the Late Mesolithic ecology. The local origin of some NPPs greatly enhances the palaeoecological interpretation, showing variations in the hydrological responses to disturbance that are much less visible in the pollen record, and helping to distinguish between local and regional vegetation changes. Other NPPs indicate burning near to the site. A substantial peak in spores of the wood-rot fungus Kretzschmaria deusta across the Ulmus decline may indicate girdling and other woodland management techniques as part of Neolithic woodland farming. 相似文献
8.
Spores ofNosema locustae Canning were applied with aerial equipment for experimental control of the Mormon cricket,Anabrus simplex Haldeman. The application resulted in infections in crickets during the season of application and the season following application. Spores were observed in cricket feces which indicated probable vertical transmission between generations. Reduced densities of crickets during the second season suggested effective control byN. locustae. 相似文献
9.
Jun-Wu Shu Naoko Sasaki Hikaru Takahara Yoshitaka Hase 《Vegetation History and Archaeobotany》2013,22(4):285-298
To better understand the response of forest vegetation to climate and fire regimes with reference to human activities over the last deglacial period in the Aso Caldera, central Kyushu, southwestern Japan, a 33.9 m long sediment core was examined in order to reconstruct the vegetational and fire history using pollen and charcoal analyses. The results show that a cool temperate broad-leaved deciduous forest, dominated by Quercus (deciduous oaks) with Carpinus and Fagus, prevailed in the Aso Valley from ca. 14.6 ka cal. b.p., indicating warming since the last glacial period. The landscape was presumably covered by a mosaic of deciduous Quercus forests and terrestrial Artemisia communities. Around 12.8–11.7 ka cal. b.p., Quercus dominated the forest and fires occurred frequently. Co-expansion of distinctive Ulmus–Zelkova and Celtis–Aphananthe forests coupled with a progressive retreat of Quercus in the early Holocene could reflect a strengthening of the East Asian summer monsoon under mild and humid climate conditions. Around 8 ka cal. b.p., significant increases in Cyclobalanopsis (evergreen oaks), Castanopsis/Castanea and Podocarpus indicate a further warming, in particular an increased winter temperature. Warm temperate lucidophyllous forests, dominated by Cyclobalanopsis, flourished after 7.3 ka cal. b.p., probably corresponding to the “Holocene Climatic Optimum” interval. Progressive expansion of Quercus at the expense of Cyclobalanopsis began around 6.4 ka cal. b.p. and paralleled an increase in charcoal until ca. 4.8 ka cal. b.p.; this could be evidence of fire disturbance induced by the early-middle Jomon people. The disturbed evergreen forest experienced a temporary recovery but then opened again from 3.6 ka cal. b.p. due to extensive fire deforestation, as suggested by the high charcoal levels during this time. Human exploitation and buckwheat (Fagopyrum) agriculture may have contributed to the opening of the forest, which allowed secondary forests (primarily Pinus and Quercus) and herbaceous communities (mainly Poaceae) to spread. These results are discussed in comparison with other high-resolution pollen data from western Japan to better elucidate the vegetation and fire history over the last deglacial in the Aso Caldera. 相似文献
10.
Two new species ofPhellinus rimosus complex are described, viz.Phellinus coffeatoporus Kotl. etPouz. from Florida (U.S.A.) characterized by globose spores andPhellinus resinaceus Kotl. etPouz. from Papua-New Guinea and Australia which is distinguished by a very thick and faintly yellowish tinted spore wall. 相似文献
11.
Due to the unique role of l-proline in the folding and structure of protein, a variety of synthetic proline analogues have been developed. l-Proline analogues have been proven to be valuable reagents for studying cellular metabolism and the regulation of macromolecule synthesis in both prokaryotic and eukaryotic cells. In addition to these fundamental researches, they are useful compounds for industrial use. For instance, microorganisms that overproduce l-proline have been obtained by isolating mutants resistant to l-proline analogues. They are also promising candidates for tuning the biological, pharmaceutical, or physicochemical properties of naturally occurring or de novo designed peptides. Among l-proline analogues, l-azetidine-2-carboxylic acid (l-AZC) is a toxic non-proteinogenic amino acid originally found in lily of the valley plants and trans-4-hydroxy-l-proline (4-l-THOP) is the most abundant component of mammalian collagen. Many hydroxyprolines (HOPs), such as 4-l-THOP and cis-4-hydroxy-l-proline (4-l-CHOP), are useful chiral building blocks for the organic synthesis of pharmaceuticals. In addition, l-AZC and 4-l-CHOP, which are potent inhibitors of cell growth, have been tested for their antitumor activity in tissue culture and in vivo. In this review, we describe the recent discoveries regarding the physiological properties and microbial production and metabolism of l-proline analogues, particularly l-AZC and HOPs. Their applications in fundamental research and industrial use are also discussed. 相似文献
12.
Magdalena Wieckowska Walter D?rfler Wiebke Kirleis 《Vegetation History and Archaeobotany》2012,21(4-5):303-320
Holocene sediment cores from contemporary terrestrialised kettle holes on two islands in the Ostholstein lakeland area, Northern Germany, were investigated by palaeoenvironmental methods. Records from such isolated locations, such as these island mires, are an important source of information on small-scale vegetation changes. Pollen, non-pollen palynomorphs and macrofossils were used to reveal anthropogenic impact as well as lake level fluctuations. Changes in the peat decomposition and the ratio of organic to minerogenic content in the sediment facilitated correlation with past ground water table levels and accordingly with former lake levels. The palynological surveys indicate that human impact on the islands expanded in prehistoric times during phases of low lake levels or periods of stable hydrological conditions. The first distinct low level is recorded between ca. 8210 and 7740?cal.?yr b.p. Another major low level period was detected for the time span from approximately 5290 to 4600?cal.?yr b.p. After a subsequent period with a wetter climate, indicated by rising and fluctuating lake levels culminating at ca. 2420 to 2180?cal.?yr b.p., a third lowering occurred until about 660?cal.?yr b.p. This period was interrupted by minor fluctuations in lake levels from ca. 1770 to 1630?cal.?yr b.p. and from ca. 1370 to 1010?cal.?yr b.p. 相似文献
13.
Two entomophthoraceous species, found at different localities in Israel, caused epizootics onHypera variabilis Herbst. larvae during spring of 1976 and 1977.Zoophthora phytonomi (Arthur) Batko, emend.Ben-Ze’ev & Kenneth (syn.Entomophthora phytonomi Arthur) produced in the field only conidia, whereasConidiobolus osmodes Drechsler formed only dark, rough-walled resting spores that had been erroneously thought in the past to belong toZ. phytonomi. In culture,Z. phytonomi, isolated from conidia, produced subhyaline, smooth resting spores, whereasC. osmodes from resting spores produced rotund conidia, which proved pathogenic toH. variabilis larvae and adult houseflies. All species connected by different authors withZ. phytonomi are discussed, includingE. elateridiphaga, transferred here toZoophthora. 相似文献
14.
Věra Holubová-Jechová 《Folia Geobotanica》1978,13(4):421-442
Three genera of lignicolousHyphomycetes Septonema Corda,Hormiactella Saac. andLylea Morgan-Jones are discussed. Illustrations and determination keys are provided. Five species ofSeptonema—S. fasciculare (Corda) Hughes,S. leptaleum (Ellis & Harkn.) Hughes,S. pinicola Hol.-Jech.,S. secedens Corda andS. laricium Hol.-Jech.—and two species ofHormiactella—H. fusca (Preuss) Sacc. andH. asetosa Hol.-Jech.—have been found in Czechoslovakia. A new speciesS. pseudobinum Hol.-Jech. is described from Romania.Septonema tetracoilum (Corda Hughes is accommodated in the genusLylea Morgan-Jones. 相似文献
15.
Miloslav Kovanda 《Folia Geobotanica》1970,5(2):171-208
A survey is given of three natural groups of the subsectionHeterophylla (Witas.)Fed. of the genusCampanula L. Within theSaxicolae four taxa of higher rank have been revealed:c. xylocarpa Kovanda (2n=34),C. gentilis Kovanda (2n=34),C. moravica (Spitzner)Kovanda subsp.moravica (2n=68), andC. moravica subsp.xylorrhiza (O. Schwarz)Kovanda (2n=102). BothAlpicolae andLanceolatae are represented by a single species: the first byC. cochleariifolia Lam. (2n=34), the latter byC. serrata (Kit. ap.Schult.)Hendrych (2n=34). Cytology, ecology and geographical distribution of all these taxa have been reviewed, and relationships to the other members of the complex discussed. Infraspecific variation within each species has also been examined. 相似文献
16.
As a part of the ELSA-project (Eifel Laminated Sediment Archive) new pollen and plant macro-remain analyses have been carried out on a series of Holocene lacustrine sediments from three open maar lakes of the Quaternary Westeifel Volcanic Field. In combination with already existing pollen analyses, the archaeological record and written sources, the present study casts new light on settlement activities and henceforth the development of agriculture from the prehistoric to historic times in this region. While there are clues that wood pasturing was practised in the Eifel region from the Michelsberg Culture onwards (c. 4300 cal. b.c.), the Vulkaneifel is a remote area with relatively poor soils and a humid climate and was not constantly settled until the Late Neolithic/Early Bronze Age, when cereal pollen was found regularly in the deposits. Plant macro-remains (chaff), which give us direct evidence for arable agriculture in the surroundings of the maars, were also found in layers belonging to the Early Bronze Age (c. 1900 cal. b.c.). At the same time we can observe the massive spread of Fagus sylvatica (beech) in all pollen diagrams, which was most probably caused by a combination of climatic, anthropogenic and competitive factors. Later impacts of agriculture were an abundance of crop weeds and pollen in the following Middle Bronze Age. Nevertheless human impact remained discontinuous until the Urnfield Culture (1200–800 cal. b.c.). A layer of weeds dating at the end of the Urnfield Culture was found and also flax (Linum usitatissimum) cultivation first becomes apparent. However, the subsequent Iron Age and Roman Period reveal only crop weeds and cereal pollen in slightly higher concentrations, but the abundance of Poaceae pollen at this time is most probably consistent with grazing activities. There follows compelling evidence of the importance of flax cultivation and processing at the maars from the Merovingian Period (5th century a.d.) onwards. A detailed insight into the agriculture of the High Medieval comes from flash flood layers of the 14th century a.d., where remains of Secale cereale (rye) and crop weeds reflect winter-sown cultivation of rye. Cannabis sativa (hemp) was also cultivated and processed during the medieval. Finally we can trace the Prussian reforestation in the 19th century a.d., with an increase in Pinus sylvestris (pine) and Picea abies (fir), by both pollen and plant macro-remains. 相似文献
17.
Antonín Vězda 《Folia Geobotanica》1972,7(2):203-215
Die beschriebene GattungGyalideopsis gen. nov. umfasst vier bisher festgestellten Arten:G. peruviana Merr. exVězda sp. n.,G. anastomosans P. James etVězda sp. n.,G. athalloides (Nyl.) Vězda comb. n. undG. muscicola P. James etVězda sp. n. Die Einreihung der GattungGyalideopsis in die FamilieAsterothyriaceae (sensuSantesson) sowie die systematische Stellung dieser Familie werden kurz behandelt. 相似文献
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Proteolytic activity of gut bacteria isolated from the velvet bean caterpillar Anticarsia gemmatalis
F. M. Pilon L. E. Visôtto R. N. C. Guedes M. G. A. Oliveira 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2013,183(6):735-747
The development of proteinase inhibitors as potential insect control agents has been constrained by insect adaptation to these compounds. The velvet bean caterpillar (Anticarsia gemmatalis) is a key soybean pest species that is well-adapted to proteinase inhibitors, particularly serine-proteinase inhibitors, which are abundant in the caterpillar host. The expression of diverse proteolytic enzymes by gut symbionts may allow the velvet bean caterpillar to circumvent proteinase inhibitors produced by the host plant. In this study, we characterized the proteolytic activity of the four nonpathogenic species of gut bacteria isolated from the velvet bean caterpillar—Bacillus cereus, Enterococcus gallinarum, Enterococcus mundtii and Staphylococcus xylosus. Two proteinase substrates, N-α-benzoyl-l-Arg-p-nitroanilide (l-BApNA) and N-α-p-tosyl-l-Arg methyl ester (l-TAME) and five proteinase inhibitors [aprotinin, E-64, ethylenediamine tetraacetic acid (EDTA), pepstatin and N-α-tosyl-l-lysine chloromethyl ketone (TLCK)] as well as CaCl2, pH and temperature profiles were used to characterize the expressed proteolytic activity of these bacterial strains in vitro. Kinetic parameters for proteolytic activity were also estimated. The results of these experiments indicated that serine- and cysteine-proteinase activities were expressed by all four gut bacteria symbionts of the velvet bean caterpillar. The cysteine- and serine-proteinase activities of these gut symbionts were distinct and different from that of gut proteinases of the caterpillar itself. This finding provides support for the potential involvement of gut symbionts in the mitigation of the negative effects of serine-proteinase inhibitors in the velvet bean caterpillar. 相似文献
20.
Natural control agents of the satin moth,Leucoma salicis (L.) were examined in 2Populus grandidentata Michaux stands. Highest mortality occurred in overwintering larvae, with the causal agents 2 fungi,Paecilomyces sp. andHirsutella gigantea Petch, a factor causing death symptomatic of a pathogen, the parasiteEupteromalis hemipterus (Walker) and death from unknown causes. Mortality fromPaecilomyces sp. andE. hemipterus was reduced where overwintering sites were covered with burlap cloth. Parasites recovered from larvae and pupae included the braconidsApanteles melanoscelus (Ratzeburg) andMeteorus versicolor (Wesmeal), the ichneumonidCoccygomimus pedalis (Cresson), the tachinidsCompsilura concinnata (Meigen),Carcelia laxifrons Villeneuve,Tachinomyia variata Curran, and the sarcophagidsSarcophaga aldrichi Parker andAgria housei Shewell. Larval and pupal predators included the carabidCalosoma frigidum Kirby, pentatomids, and birds, particularly black-billed cuckoos,Coccyzus erythrophthaimus (Wilson). Eggs were parasitized by the scelionidTelenomus prob.californicus Ashmead and the trichogrammidTrichogramma minutum (Riley). Predators of adult satin moths included the hermit thrush,Hylocichla guttata (Pallas), and pentatomid bugs. 相似文献