The impact of the termination technology of agro-ecological service crops on soil properties in open field vegetable production

ArticleThe agro - ecological service crops (ASC) are introduced in the agro - ecosystems to provide or enhance ecological services, thus promoting the whole soil - plant system equilibrium. To avoid competition with the subsequent cash crops, the growth of the interposed ASC is terminated in advance of the cash crop planting. The traditional, most widespread technique to terminate the ASC is incorporation as green manure into the soil by tillage (GM). However, since tillage includes energy and labour consuming and soil dis turbing operations, the use of no/reduced tillage techniques (as the roller crimping technology - RC) has received increasing interest. An international research consortium (SOILVEG) including Estonian Crop Research Institute, was established in 2015 with th e aim to study among others the impact of ASC termination on soil dry bulk density (BD), water content, soil structure and microbiological activity. Data are collected from Estonian tri als in 2016 and 2017 at Jõgeva. The physical properties of 0 – 40 cm soil layers were determined. Higher BD in soil layers (0 – 20 cm) of plots with ASC and RC was determined comparing to the GM and control plots. Bigger water content in same layer of plots with ASC and the RC was determined comparing to the GM plots. The use of the ASC - s helped to arise ratio of agronomically preferred soil particles. Microbial activity was estimated by assessing of enzyme dehydrogenase activity in 0 – 20 cm soil layer. There were no statistically relevant differences in soil dehydrogenase activit y (DHA) be tween the RC and GM treatments

Fodder galega (Galega orientalis Lam) grass potential as a forage and bioenergy crop

ArticleFodder galega (Galega orientalis Lam.) is a forage legume that has been grown in Estonia for almost forty five years. Pure galega is known to be persistent, high-yielding crop and rich in nutrients, in particular crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF). Galega is usually grown in a mixture with grass in order to optimize its nutrient concentration, increase dry matter (DM) yield and improve fermentation properties. The trial plots were established on a typical soddy-calcareous soil. There are certain grass species suitable for the mixture. In this study galega mixtures with reed canary grass cv. ‘Marathon’, timothy cv. ‘Tika’, red fescue cv. ‘Kauni’ and festulolium cv. ‘Hykor’ were under investigation in three successive years (2013–2015). In order to increase competitiveness of grasses and the yield of the first cut, two N fertilization levels were used: N0 and N50 kg ha-1 . Two cuts were carried out during the growing season in all three years. The total dry matter yield varied from 9.1 to 12.8 t ha-1 . The NDF concentration in the DM varied from 495−559 g kg-1 . Both DM-yield and NDF were dependent on the year, mixture, cutting time and fertilization. Nitrogen fertilization (N50 kg ha-1 ) favoured grass growth and reduced the role of galega in the sward

Sammalten etäsuojeluopas

Tämä on todennäköisesti ensimmäinen uhanalaisten sammalten ex situ -suojelumenetelmien opas maailmassa. Ex situ -suojelun, tai suomalaisittain etäsuojelun, piiriin kuuluvat menetelmät, joiden avulla uhanalaisia lajeja pyritään suojelemaan muualla kuin niiden alkuperäisissä ympäristöissä. Lajien suojeleminen luonnossa, eli in situ -suojelu, on ensisijainen suojelun muoto, koska samalla voidaan suojella arvokkaita elinympäristöjä ja niiden geneettistä ja toiminnallista monimuotoisuutta. Etäsuojelu tukee in situ -suojelua ja varmistaa geneettisen monimuotoi- suuden säilymisen esimerkiksi habitaatin äkillisen tuhoutumisen varalta. Se myös muodostaa reservin uhanalaisten lajien palauttamiselle ja osaltaan torjuu ilmastonmuutoksen aiheuttamaa uhkaa lajistollemme

The meristem-associated endosymbiont Methylorubrum extorquens DSM13060 reprograms development and stress responses of pine seedlings

Microbes living in plant tissues-endophytes-are mainly studied in crop plants where they typically colonize the root apoplast. Trees-a large carbon source with a high capacity for photosynthesis-provide a variety of niches for endophytic colonization. We have earlier identified a new type of plant-endophyte interaction in buds of adult Scots pine, where Methylorubrum species live inside the meristematic cells. The endosymbiont Methylorubrum extorquens DSM13060 significantly increases needle and root growth of pine seedlings without producing plant hormones, but by aggregating around host nuclei. Here, we studied gene expression and metabolites of the pine host induced by M. extorquens DSM13060 infection. Malic acid was produced by pine to potentially boost M. extorquens colonization and interaction. Based on gene expression, the endosymbiont activated the auxin- and ethylene (ET)-associated hormonal pathways through induction of CUL1 and HYL1, and suppressed salicylic and abscisic acid signaling of pine. Infection by the endosymbiont had an effect on pine meristem and leaf development through activation of GLP1-7 and ALE2, and suppressed flowering, root hair and lateral root formation by downregulation of AGL8, plantacyanin, GASA7, COW1 and RALFL34. Despite of systemic infection of pine seedlings by the endosymbiont, the pine genes CUL1, ETR2, ERF3, HYL, GLP1-7 and CYP71 were highly expressed in the shoot apical meristem, rarely in needles and not in stem or root tissues. Low expression of MERI5, CLH2, EULS3 and high quantities of ononitol suggest that endosymbiont promotes viability and protects pine seedlings against abiotic stress. Our results indicate that the endosymbiont positively affects host development and stress tolerance through mechanisms previously unknown for endophytic bacteria, manipulation of plant hormone signaling pathways, downregulation of senescence and cell death-associated genes and induction of ononitol biosynthesis.Peer reviewe

Effects of lake sediment on soil chemical composition, dehydrogenase activity and grain yield and quality in organic oats and spring barley succession

In organic farming, it is important to maintain soil fertility with organic fertilisers; often organic compost, manure, or slurry is used. However, the effects of lake sediment in maintaining and improving soil fertility are less studied. The direct and residual effects of a one-time application of 50 t ha-1 or 100 t ha-1 of lake sediment were compared to an unfertilised control for oats (Avena sativa) (2015) followed by spring barley (Hordeum vulgare) in 2016, under organic farming conditions. Soil chemical composition, microbial activity in the 0–20 cm soil layer, grain yield, and grain quality were tested. The application rate, 100 t ha-1 , increased (P < 0.05) the soil organic carbon (SOC), the amount of mobile calcium (Ca), total nitrogen (Ntot), and boron (B) content in soil. Both application rates increased (P < 0.05) the amount of magnesium (Mg), copper (Cu), and manganese (Mn) content in the soil. The application rate had no effect on soil pH. Soil dehydrogenase activity (DHA) was higher (P < 0.05) at 100 t ha-1 than the control and the lower application rate. Both rates of lake sediment application significantly (P < 0.05) increased the grain yield and test weight for oats in 2015. Positive residual effects on spring barely yield only occurred in the 100 t ha-1 treatments in 2016. No residual impact of lake sediment was found on spring barely quality

Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch

Peer reviewe

Prevalence analysis of putative periodontal pathogens in patients with aggressive periodontitis and healthy elderly

Marginale Parodontitis, die multikausale Erkrankung des Parodonts ist eine Infektionskrankheit, modifiziert durch Wirtsfaktoren und äußere Einflüße. Die als pathogene Mischflora bezeichnete Kombination kommensaler Mikroorganismen spielt die primäre Rolle in der Ätiopathogenese der Parodontitis. In der Aufstellung des Studienziels wurden einzelne Bakterienarten (T. forsythensis, P. gingivalis, A. actinomycetemcomitans, C. rectus, F. nucleatum, Fusobacterium spp., P. intermedia, E. corrodens, V. parvula und C. ochracea) ausgewählt, die eventuell als "Markerkeime" in der aggressiven Form der Parodontitis betrachtet werden können. Dazu wurde eine Kontrollgruppe untersucht, die eine gesunde parodontale Flora besitzt. Die angewandte Nachweismethode basiert auf der PCR-Amplifikation von 16S rDNA und darauffolgender dot-blot Hybridisierung mit Oligonukleotidsonden. Die entsprechenden Sonden wurden hergestellt, optimiert und evaluiert. Für die epidemiologische Untersuchung wurde subgingivale Plaque von vier Parodontaltaschen und einer Kontrollstelle von 45 Patienten mit aggressiver Parodontitis, sowie an fünf Stellen von 21 Senioren entnommen. Die Prävalenz der einzelnen Bakterienarten wurde mit Hilfe des Chi-Quadrat Test verglichen. Obgleich eine hohe interindividuelle Variabilität der Kolonisationsmuster zu beobachten war, konnten T. forsythensis, P. gingivalis, C. rectus und F. nucleatum signifikant häufiger in den Parodontaltaschen als an den gesunden Stellen nachgewiesen werden und können deswegen als "Leitkeime" der aggressiven Parodontitis angesehen werden. A. actinomycetemcomitans konnte nur bei einzelnen Patienten mit aggressiver Parodontitis festgestellt werden. Die Ergebnisse für P. intermedia und E. corrodens ließen keine eindeutige Assoziation sowohl mit der aggressiven Parodontitis als auch mit dem gesunden Parodontalzustand zu. Bei Senioren wurde C. ochracea besonders häufig nachgewiesen. Die Ergebnisse dieser Studie bewiesen die erfolgreiche Einsetzbarkeit der hergestellten Oligonukleotidsonden.A multifactorial risk pattern of periodontitis has been recognized, where in addition to host and environmental factors, a pathogenic microbiota plays a primary role. The purpose of the current research was to analyze the prevalence of periodontitis-associated microorganisms in patients with aggressive periodontitis and periodontally healthy elders by using molecular-biologic detection methods like eubacterial PCR-amplification of 16S rDNA in combination with dot-blot hybridization. The oligonucleotide probes for the detection of T. forsythensis, P. gingivalis, A. actinomycetemcomitans, C. rectus, F. nucleatum, Fusobacterium spp., P. intermedia, E. corrodens, V. parvula and C. ochracea were designed and evaluated. The PCR products of 42 cultivated target and closely related bacteria were used for the optimization of hybridization conditions. For the epidemiological study, subgingival plaque was sampled from four pockets and one healthy site of 45 aggressive periodontitis patients as well as from five sites of 21 elderly. The differences in the prevalence of bacterial species were analyzed by the chi-square test. The data revealed frequent colonization by T. forsythensis, P. gingivalis, F. nucleatum and C. rectus in patients with aggressive periodontitis, however individual variations were obvious. These species could be predominantly identified in periodontal pockets, but were significantly less common in the healthy sites of the periodontitis patients and in the elderly. These putative pathogens can be conclusively determined as the key-bacteria in patients with aggressive periodontitis. No direct association for P. intermedia and E. corrodens with aggressive periodontitis or periodontal health could be seen. A. actinomycetemcomitans could be detected in only a few patients, reducing its suspected importance in the etiology of aggressive periodontitis. C. ochracea was highly prevalent in the well-maintained elderly, suggesting its association with healthy flora. The results of the study confirmed the reliability of the oligonucleotide probes in a specific and sensitive detection of the respective oral species

Erinevate viljelusviiside mõju mikroobide koosseisule ja aktiivsusele mullas

Liina Edesi thesis „The influence of cultivation methods on soil microbial community composition and activity“ is based on the long-term research, focused on comparison of organic (with and without cattle manure) and conventional (with cattle manure, mineral fertilizers and pesticides) cultivation methods and their impact on the soil microbe community composition (abundance of the total number of bacteria, molds, yeasts, mesophilic spore-forming bacteria, Fusarium spp., actinomytcetes, azotobacteria, cellulose decomposers, denitrifying and nitrifying bacteria) and on soil microbial biomass and activity under field conditions, within the typical Estonian crop rotation. The aim of this study was to investigate the impact of manure, crop and pesticides on the soil microbe community composition and on soil microbial biomass and activity. The results showed that the application of solid cattle manure in organic treatment compared to the organic treatment without manure increased the abundance of the total number of bacteria, yeasts, denitrifying bacteria, and the soil enzymatic activities. The use of solid cattle manure had a positive effect on the abundance of mesophilic spore-forming bacteria, nitrifying bacteria, cellulose decomposers and enzyme phosphomonesterase activity. It was similar in conventional treatments where the mineral fertilizers and pesticides in addition to manure were used. The treatments with cattle manure showed a better ability to suppress Fusarium spp. The cultivation of red clover in crop rotation was promotive to molds, Fusarium spp., as well as to nitrifying bacteria and cellulose decomposers in soil. However, the cultivation of oats inhibited abundance of Fusarium spp. and promoted the abundance of yeasts, which is in antagonistic relationship with Fusarium spp.. In conventional treatment, the use of pesticides (active ingredients – metribuzin, metalaxyl, fluazinam, mancozeb and MCPA) decreased the abundance of total number of bacteria, spore-forming bactera, mold, yeasts, denitrifying bacteria and dehydrogenase activity. However, after a period of time, the population and dehydrogenase activity returned almost to the same level as in organic treatments fertilised with solid cattle manure. The use of pesticides had no influence on the abundance of actinomycetes and nitrifying bacteria in soil. Present research revealed that the use of solid cattle manure in crop rotation increases microbial activity and microbial abundance in the soil, while inhibiting the Fusarium spp. fungal development. Mold incl. Fusarium spp. abundance in the soil decreased during oat cultivation. Despite of decrase of abundance and activity of soil microbes because of use of pesticides, the microbial population was able to recover itself.Liina Edesi doktoritöö „ Erinevate viljelusviiside mõju mikroobide koosseisule ja aktiivsusele mullas“ raames viidi 2007–2013. aastal läbi põldkatse, milles uuriti viieväljalises külvikorras mahepõllumajandusliku (sõnnikuga ja sõnnikuta) ja tavapõllumajandusliku (sõnniku, mineraalväetiste ja pestitsiididega) viljelusviisi mõju mullas elavate mikroobikoosluste mikroobide arvukusele (bakterite üldarv, hallitusseened, pärmid, Fusarium spp., mesofiilsed eosbakterid, nitrifitseerijad, denitrifitseerijad, aktinomütseedid, azotobakterid ja tselluloosilagundajad) ja mulla mikroobsele biomassile ning mikrobioloogilisele aktiivsusele. Doktoritöö eesmärgiks oli välja selgitada milline on taheda veisesõnnikuga väetamise, külvikorras kasvava kultuuri ning pestitsiidide mõju mullas elavate mikroobide arvukusele ning aktiivsusele. Uurimistulemustest selgus, et bakterite üldarv, pärmide ja denitrifitseerijate arvukus ja mikrobioloogiline aktiivsus oli suurim mahepõllumajanduslikus sõnnikuga väetatud variandis ja madalaim mahepõllumajanduslikus sõnnikut mitte saanud variandis. Leiti, et veisesõnnikul oli positiivne mõju nii mesofiilsetele eosbakteritele, nitrifitseerijatele, tselluloosilagundajatele ja seda isegi tavapõllumajanduslikus variandis, kuna nende arvukus oli selles variandis suurem kui veisesõnnikut mitte saanud mahepõllumajanduslikus variandis. Sõnnikuga väetatud mullal avaldus ka suurem Fusarium spp. allasurumise võime. Katsetulemuste põhjal võib järeldada, et ristiku kasvatamine külvikorras soodustas nii hallitussente, sh ka Fusarium spp., nitrifitseerijate kui ka tselluloosilagundajate arengut mullas. Samal ajal kaera kasvatamine pärssis Fusarium spp. seente arvukust, soodustades samal ajal Fusarium spp. seentega antagonistlikus suhtes olevate pärmide arengut. Tavapõllumajanduslikus variandis intensiivne pestitsiidide (toimeained – metribusiin, metalaksüül, mankotseeb, fluasinaam ja MCPA) kasutamine vähendas bakterite üldarvu, mesofiilsete eosbakterite, hallitusseente, pärmide, denitrifitseerijate arvukust ning mikrobioloogilist aktiivsust mullas. Järgmisel kasvuperioodil, kui pestitsiidide kasutamine oli väiksem, mikroobide populatsioon ja mikrobioloogiline aktiivsus mullas taastusid ja jäid praktiliselt samale tasemele, mis oli mahepõllumajanduslikus sõnnikuga väetatud variandis. Katses kasutatud pestitsiidid ei omanud olulist mõju nitrifitseerijate ja aktinomütseetide arvukusele mullas. Läbiviidud uurimistööst järeldus, et taheda veisesõnniku kasutamine külvikorras suurendab mikrobioloogilist aktiivsust ning mikroobide arvukust mullas, samal ajal pärssides Fusarium spp. seente arengut. Hallitusseente sh. Fusarium spp. arvukus mullas väheneb ka kaera kasvatamise korral. Kuigi uurimistöös taimehaiguste, -kahjurite ning umbrohtude tõrjeks kasutatud pestitsiidide tagajärjel mikroobide arvukus ning aktiivsus mullas vähenes, selgus, et kasutatavate pestitsiidikoguste vähenedes oli mikroobide populatsioon võimeline taastuma

The effect of light spectral quality on cryopreservation success of potato (<em>Solanum tuberosum</em> L.) shoot tips <em>in vitro</em>

Abstract Cryopreservation enables storage of genetic resources at ultra-low temperatures (&#60;-150&#176;C) while maintaining viability and regeneration capability. The method is especially suitable for long-term preservation of plant materials that cannot be stored as seeds. The genetic resources of potato (Solanum tuberosum L.), one of the most important food crops in the world, are preserved almost entirely by vegetative preservation. Cryopreservation is therefore increasingly applied for securing potato genetic resources in plant genebanks. A major challenge is, however, that recovery percentages can extensively vary among different genotypes. Light spectral quality is among the most important factors affecting plant growth and morphogenesis, but its effect with regard to cryopreservation has not been studied. In the present thesis, I studied the effect of six different light qualities on cryopreservation success of five potato cultivars before and after cryopreservation. I also explored how the different light conditions affect gene transcript abundance of recovering potato shoot tips. The results indicate that light spectral quality significantly affects the cryopreservation success of potato shoot tips in vitro. Prior to cryopreservation, cultivation under blue LEDs resulted in high initial survival, while post-cryopreservation exposure to a combination of red and blue LEDs (90% red, 10% blue) doubled the regeneration percentages. Concurrently, for most cultivars, red LEDs had adverse effects both before and after cryopreservation. The transcriptome analysis of potato shoot tips revealed the complex and extensive effect of cryopreservation on transcript abundance. Moreover, the expression level of stress- and defence-responsive genes was affected by light spectral quality. The positive effect of red-blue LEDs on shoot formation could tentatively be associated with a higher level of morphogenesis-related transcripts and lower level of stress and defence-responsive transcripts. The present thesis reveals that light spectral quality is an additional non-cryogenic factor, which can significantly increase the cryopreservation efficiency of plant germplasm.Tiivistelmä Syväjäädytys mahdollistaa geenivarojen säilytyksen erittäin alhaisissa lämpötiloissa (&#60;-150&#176;C), siten että niiden elin- ja uusiutumiskyky säilyvät. Menetelmä soveltuu erityisesti sellaisten kasvimateriaalien pitkäaikaissäilytykseen, joita ei voida säilöä siementen avulla. Peruna (Solanum tuberosum L.) on yksi maailman tärkeimmistä ruokakasveista ja sen geenivaroja säilytetään lähes pelkästään vegetatiivisesti. Syväjäädytysmenetelmää käytetäänkin kasvavissa määrin perunan geenivarojen taltioimiseen geenipankeissa. Haasteena on kuitenkin syväjäädytyksen jälkeinen suuri vaihtelu elpymisprosenteissa eri genotyyppien välillä. Valon laatu on yksi tärkeimmistä kasvien kasvuun ja kehitykseen vaikuttavista tekijöistä, mutta sen vaikutusta syväjäädytyksen yhteydessä ei ole tutkittu. Väitöskirjassani tutkin kuuden erilaisen valonlaadun vaikutusta sekä syväjäädytystä edeltävän että sen jälkeisen kasvatuksen aikana viiden perunalajikkeen selviytymiseen. Lisäksi tutkin, miten erilaiset valo-olosuhteet vaikuttivat geenien ilmenemiseen elpyvissä perunan versonkärjissä. Tutkimukseni osoitti, että valon laatu vaikuttaa merkittävästi perunan versonkärkien kykyyn elpyä syväjäädytyksestä in vitro -olosuhteissa. Kun perunan versonkärkiä kasvatettiin sinisten LED-valojen alla ennen syväjäädytystä, niiden elävyysprosentit olivat korkeita, kun taas syväjäädytystä seuraava kasvatus sinipunaisten LED-valojen (90 % punaista, 10 % sinistä) alla kaksinkertaisti uusiutumisprosentit. Samanaikaisesti suurimmalle osalle lajikkeista punaisilla LED-valoilla oli epäsuotuisat vaikutukset selviytymiseen sekä syväjäädytystä edeltävän, että sitä seuraavan kasvatuksen aikana. Perunan kärkisilmujen geeniekspressioanalyysi osoitti, että syväjäädyttäminen aiheuttaa laajoja ja monitahoisia vaikutuksia kasvin geenien toiminnassa. Valon laatu vaikutti erityisesti stressi- ja puolustusgeenien ilmenemiseen. Tulokset viittaavat siihen että sinipunaisten LED-valojen uusiutumista edistävä vaikutus voi liittyä morfogeneesissä toimivien geenituotteiden runsauteen ja toisaalta stressi- ja puolustusgeenituotteiden määrän laskuun. Kaiken kaikkiaan tutkimukseni osoitti, että valon laatu on tärkeä ei-kryogeeninen tekijä, joka voi lisätä kasvien syväjäädytyksen tehokkuutta

Root Rot Resistance Locus PaLAR3 Is Delivered by Somatic Embryogenesis (SE) Pipeline in Norway Spruce (Picea abies (L.) Karst.)

Research Highlights: The Norway spruce somatic embryogenesis (SE) pipeline is suitable for multiplication of material with root rot resistance traits. Background and Objectives: Heterobasidion root rot is the economically most severe forest pathogen in Europe, reducing the benefit of planting elite forest material. In this study, the SE-propagation ability of elite Norway spruce material carrying root rot resistance traits was studied. Materials and Methods: We analyzed the presence of the root rot resistance locus PaLAR3B among 80 Finnish progeny-tested Norway spruce plus-trees used for SE-plant production as well as in 241 SE lines (genotypes) derived from them. Seven full-sib families with lines having either AA, AB, or BB genotype for PaLAR3 locus were further studied for their SE-plant propagation ability. Results: The results indicate that 47.5% of the studied elite trees carry the PaLAR3B allele (45% are heterozygous and 2.5% homozygous). The resistance allele was present among the SE lines as expected based on Mendelian segregation and did not interfere with somatic embryo production capacity. All embryos from PaLAR3 genotypes germinated well and emblings were viable in the end of first growing season. However, in three families, PaLAR3B homo- or heterozygotes had 23.2% to 32.1% lower viability compared to their respective hetero- or PaLAR3A homozygotes. Conclusions: There is no trade-off between root rot resistance locus PaLAR3B and somatic embryo production ability, but the allele may interfere with Norway spruce embling establishment