Soil bacterial community in potato tuberosphere following repeated applications of a common scab suppressive antagonist

Disease suppressive soils are important for managing soil-borne diseases that cannot be controlled with chemicals. One such disease is the potato common scab caused by Streptomyces species. Suppressiveness against common scab can develop spontaneously in fields where potato is grown for years without interruption, and this has been attributed to non-pathogenic Streptomyces strains. Streptomyces spp. have been used as inoculants in biological control, but their long-term effects have gained less attention. In our previous studies, a nonpathogenic Streptomyces strain (Str272) isolated from a potato common scab lesion suppressed common scab in field trials lasting over 5 years. In this study, bacterial communities in the tuberosphere i.e. in the soil adjacent to potato tubers, were analysed by next generation sequencing (NGS). The aim was to compare bacterial communities in untreated control plots to those in which seed tubers were treated with Str272 in one or several growing seasons. Str272 applications increased soil bacterial diversity and affected the bacterial composition in the potato tuberosphere. The most pronounced differences were observed between the untreated control and the treatments in which the antagonist had been applied in three or four consecutive years. The differences remained similar until the following growing season. Bacterial composition after repeated antagonist applications was associated with lower common scab severity. The antagonist applications had no or only slight effect on the number or abundance of OTUs belonging to Actinobacteria or Streptomyces, and no differences in quantities of pathogenic Streptomyces populations were detected by qPCR. This indicates that suppression of common scab by Str272 may not be based on direct effect on the common scab pathogens but is more likely to be associated with the alterations of the soil bacterial community. The most abundant bacteria phyla in the potato tuberosphere were Actinobacteria, Proteobacteria and Acidobacteria. However, the OTUs responding greatest to the antagonist treatments belonged to Bacterioidetes and Gemmatimonadetes. Results indicate that repeated applications of Str272 can change the bacterial community in the potato tuberosphere and lead to development of soil that is suppressive against potato common scab for several growing seasons after the last application.Peer reviewe

Implementation and initial calibration of carbon-13 soil organic matter decomposition in the Yasso model

Soils account for the largest share of carbon found in terrestrial ecosystems, and their status is of considerable interest for the global carbon cycle budget and atmospheric carbon concentration. The decomposition of soil organic matter depends on environmental conditions and human activities, which raises the question of how permanent are these carbon storages under changing climate. One way to get insight into carbon decomposition processes is to analyse different carbon isotope concentrations in soil organic matter. In this paper we introduce a carbon-13-isotope-specific soil organic matter decomposition add-on into the Yasso soil carbon model and assess its functionality. The new C-13-dedicated decomposition is straightforward to implement and depends linearly on the default Yasso model parameters and the relative carbon isotope (C-13/C-12) concentration. The model modifications are based on the assumption that the heavier C-13 atoms are not as reactive as C-12. The new formulations were calibrated using fractionated C, C-13 and delta(13) measurements from litterbags containing pine needles and woody material, which were left to decompose in natural environment for 4 years. The introduced model modifications considerably improve the model behaviour in a 100-year-long simulation, where modelled delta(13) is compared against fractionated peat column carbon content. The work presented here is a proof of concept and enables C-13 to be used as a natural tracer to detect changes in the underlying soil organic matter decomposition.Peer reviewe

Unenaikainen aivojen sähköinen purkaustoiminta lapsen kognitiivisen suoriutumiskyvyn heikkenemisen ja käytösoireiden syynä

TAUSTA : Jatkuva unenaikainen purkaustoiminta aivosähkökäyrässä (EEG) ja siitä johtuva CSWS-oireyhtymä ovat joskus lapsen epilepsiaan liittyvä ilmiö, jonka vaikutuksesta oppiminen, käytös, vireys ja tarkkaavaisuus huononevat huomattavasti. Tutkimme CSWS-oireyhtymän syitä, hoitoa ja tuloksia omassa potilasaineistossamme. POTILAAT JA MENETELMÄ : Tyksin aineistosta kerättiin ajalta 2006-2016 CSWS-potilaiden sairauskertomustiedot. Kriteerit täyttäneitä potilaita oli 17, ja heitä seurattiin 1,5-9 vuotta. TULOKSET : CSWS:n taustalla on geneettisiä ja hankinnaisia pre- ja perinataalisia syitä. Yhdeksällä potilaalla oli rakenteellisia aivomuutoksia, kuten polymikrogyriaa, talamushypoplasiaa, hydrokefalusta taikka aivoverenvuodon tai -infarktin jälkitila. Kahdeksalla potilaalla CSWS:n alkamista edelsi lääkitys natriumkanavan salpaajalla. Seurannassa todettiin kognitiivisen suoriutumiskyvyn heikkenemistä, ja kymmenen lasta suoriutui kehitysvammaisen tasolla. Kymmenestä potilaasta yhdeksän EEG normaalistui murrosiässä. ​​​​​​​PÄÄTELMÄT : Epilepsiaa sairastavan lapsen kognitiivisen suoriutumiskyvyn heikkenemisen ja käytösmuutosten taustalla tulisi osata epäillä CSWS-oireyhtymää.</p

Increased Inhibition in Non-Primary Motor Areas of String-Instrument Players: A Preliminary Study with Paired-Pulse Transcranial Magnetic Stimulation

Peer reviewe

Onko kotimaisilla taimilla mahdollisuuksia mansikanviljelyssä

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Aivokasvainten hoito ja moniammatillinen neuro-onkologiaryhmä

Kallonsisäisissä kasvaimissa haasteet kuvantamisessa, molekyylipatologiassa ja hoidonvasteen arvioinnissa ovat suurempia kuin monissa yleisemmissä syövissä. Hiljattainpäivitetty molekyylimuutoksiin perustuva WHO:n keskushermoston kasvainten luokitteluon oleellinen sekä hoidon valinnassa että haittavaikutusten riskin arviossa. Neuro-onkologiaryhmässäneurokirurgi, syöpälääkäri, neurologi, neuroradiologi ja -patologi täydentävät toistensaerityisosaamista. Monialainen hoidon suunnittelu parantaa ja yhdenmukaistaa laatuaja mahdollisesti ennustetta, vaikka näyttö aikuisten glioomassa on vasta alustavaa.Ryhmän ohjeistama seuranta helpottaa ymmärtämään hoitojen vaikutusta potilaan toimintakyvynsäilyttämiseen. Samalla ryhmä saa palautetta hoidon tehosta ja viiveet vähenevät,kun koordinoidaan diagnostiikka ja hoidon toteutus kansainvälisiä ja kansallisia suosituksianoudattaen. Palaute on keskeistä neuro-onkologisen hoidon vaikuttavuuden ja laadunkehittämiselle.</p

Similar temperature sensitivity of soil mineral-associated organic carbon regardless of age

Most of the carbon (C) stored in temperate arable soils is present in organic matter (OM) intimately associated with soil minerals and with slow turnover rates. The sensitivity of mineral-associated OM to changes in temperature is crucial for reliable predictions of the response of soil C turnover to global warming and the associated flux of carbon dioxide (CO2) from the soil to the atmosphere. We studied the temperature sensitivity of C in 63 mu m fractions rich in particulate organic matter (POM). The fractions were isolated by physical separation of two light-textured arable soils where the C4-plant silage maize had replaced C3-crops 25 years ago. Differences in C-13 abundance allowed for calculation of the age of C in the soil-size fractions (old C, C3-C > 25 years; recent C, C4-C <25 years). We incubated bulk soils ( <2 mm) and size fractions sequentially at 6, 18, 26 and 34 degrees C (ramping up and down the temperature scale) and calculated the temperature sensitivity of old and recent C from (CO2)-C-12 and (CO2)-C-13 evolution rates. The temperature sensitivity was similar or slightly higher for POM than for MOM. Within the POM fraction, old C3-C was more sensitive to changes in temperature than recent C4-C. For the MOM fraction, the temperature sensitivity was unrelated to the age of C. Quantitative PCR analysis indicated that the proportions of bacteria, archaea and fungi did not change during incubation. Our results suggest that while OM stabilizing mechanisms affect the temperature sensitivity of soil C, temperature sensitivity appears unrelated to the age of mineral-associated OM.Peer reviewe