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Mikrolevät ovat yksisoluisia organismeja, jotka sisältävät lajista ja kasvatusolosuhteista riippuen proteiineja 25–63 % kuivapainosta, lipidejä 2–25 % kuivapainosta, hiilihydraatteja 35–57 % kuivapainosta ja kivennäisaineita 6–30 % kuivapainosta. Lipideistä 15–57 % on triasyyliglyseroleja ja 0,7–37 % poolisia lipidejä, kuten fosfo- ja glykolipidejä. Mikrolevien koostumusta sekä mikrolevien lipidien uuttoa on tutkittu aiemmin Helsingin yliopistossa, ja näissä tutkimuksissa on herännyt tarve lisätiedolle mikrolevien poolisista lipideistä. Tämän tutkimuksen tavoitteena oli luokitella mikrolevien sisältämät lipidit poolisuuden mukaan selvittäen osuudet rasvahappokoostumuksen perusteella. Lisäksi tavoitteena oli kehittää HPLC-menetelmä mikrolevien fosfo- ja glykolipidien määrittämiseen. Poolisten lipidien rasvahappojen määrityksessä mikroleväuutteiden lipidit erotettiin poolisuuden mukaan kiinteäfaasiuutolla ja uutteista määritettiin rasvahappopitoisuudet kaasukromatografisesti. HPLC-menetelmä kehitettiin tutkimalla poolisten lipidien profiileja nestekromatografia-valonsirontadetektorilla (LC-ELSD). Kehitetyllä LC-ELSD-menetelmällä tutkittiin Euglena gracilis ja Selenastrum sp. -mikrolevänäytteiden poolisia lipidiluokkia. Mikrolevänäytteissä esiintyvät fosfo- ja glykolipidit tunnistettiin nestekromatografia-massaspektrometrisesti (LC-MS). Tutkimuksen tuloksista selvisi, että Selenastrum sp. -mikrolevän kokonaislipidipitoisuus oli suurempi kuin E. gracilis -mikrolevän. Molemmilla lajeilla eniten rasvahappoja oli poolisissa lipideissä ja molempien lajien rasvahappokoostumukset vaihtelivat kasvatuserästä ja -olosuhteista riippuen. Kehitetyllä LC-ELSD-menetelmällä mikrolevänäytteiden poolisten lipidien profiileissa erotettiin monogalaktosyylidiasyyliglyseroli (MGDG) ja fosfolipidit luokkana. Tulosten perusteella MGDG vaikuttaisi olevan yleisin glykolipidi tutkituissa mikrolevänäytteissä ja fosfatidyylietanolamiini yleisin fosfolipidi. Glyko- ja fosfolipidiluokissa ei ollut eroa mikrolevälajien tai kasvatuserien välillä. Mikrolevien MGDG:t vaikuttivat sisältävän monityydyttymättömiä rasvahappoja ja fosfolipidit tyydyttyneitä tai kertatyydyttymättömiä rasvahappoja. Lisätutkimusta tarvitaan poolisten lipidien kvantitatiiviseen määrittämiseen ja menetelmän kehittämiseen fosfolipidien erottumisen osalta.

Ruokasipuli (Allium cepa L.) on yksi Suomen eniten viljellyistä avomaan vihanneksista. Sipulin fosforinotosta on vähän kotimaisia tutkimustuloksia ja nykyiset fosforilannoitusmäärät perustuvat asiantuntija-arvioihin ja laskennallisiin keskiarvoihin fosforin otosta. Fosfori on kasveille välttämätön makroravinne, jonka puute heikentää merkittävästi kasvien kasvua. Lannoitteiden sisältämä fosfori on louhittu pääosin uusiutumattomista luonnonvaroista, joten fosforilannoitteiden käytön tulisi olla ympäristön kannalta järkevää. Sipulin fosforinottoa tutkittiin 2014 kahdella maalajilla (karkea hieta, korkea fosforipitoisuus ja hiuesavi, välttävä fosforipitoisuus) Luonnonvarakeskuksen toimipaikalla Piikkiössä. Tutkimuksen tavoitteena oli selvittää fosforilannoitustasojen vaikutus sipulin kasvuun, ravinteikkuuteen ja satoon sekä seurata maaperän liukoisen fosforin pitoisuutta kasvukaudella. Tutkimuksessa mitattiin sipulin lehtien kasvu ja ravinnepitoisuus kerran kasvukauden aikana, sekä sadonkorjuun jälkeen satotaso, sipulien ja lehtien ravinnepitoisuus sekä sadon mukana poistuneet ravinteet. Maan helppoliukoisen fosforin pitoisuutta seurattiin viikoittaisilla maanäytteillä. Neliportaisen lannoituskokeen tulokset osoittivat, ettei yksivuotisella lannoituskokeella saatu esiin tilastollisesti merkitseviä eroja satomäärissä tai sadon mukana poistuneiden ravinteiden määrissä eri lannoitustasojen välillä. Fosforilannoitus vaikutti sipulien ravinnepitoisuuksiin vain yksittäisten ravinteiden osalta. Myös maan liukoisen fosforin pitoisuudet tasoittuivat lannoituseroista huolimatta nopeasti samalle tasolle kummallakin maalajilla. Sipulin ravinteiden otto oli hietamaalla 22–26 kg P /ha, 86–102 kg N /ha ja 92–111 kg K /ha ja savimaalla 18–20 kg P/ha, 84–90 kg N /ha ja 92–101 kg K /ha. Sipuleissa ei havaittu fosforinpuutosta, eikä kasvustonäytteiden perusteella voida sanoa, soveltuuko sipulikasvuston mittaaminen tai lehtien ravinteiden analysointi mittaamaan kasvuston fosforin ottoa tai tunnistamaan fosforinpuutoksen oireita. Kokeen tulosten perusteella nykyisin käytettävät fosforilannoitusmäärät ovat sipulin sadonmuodostuksen kannalta riittävät.

Phosphorus is one of the three main nutrients for plants and sufficient phosphorus uptake is a prerequisite for crop production. Phosphorus exists in organic and inorganic forms in soil, and the stability and biological availability of different forms of phosphorus vary. Fertilizer phosphorus is efficiently adsorbed by aluminium and iron oxides in mineral soils, and due to positive phosphorus balances in the last decades, cultivated soils contain residual phosphorus. In addition to topsoil, phosphorus can accumulate in soil layers below the plough layer. Knowing the size of the phosphorus reserves in soil profile and the proportions of different forms of phosphorus could provide a more reliable assessment of the possibilities for utilizing and considering phosphorus reserves for example in fertilization. The aim of this study was to investigate the distribution and stocks of different forms of phosphorus in depth profiles of conventionally and organically managed clay soil and in unmanaged natural grassland. In a field experiment that has lasted 24 years before the sampling, conventional plots were fertilized with inorganic fertilizers, and organically managed plots with organic fertilizers. Total phosphorus, organic phosphorus, and water-extractable phosphate phosphorus were determined in 10 cm layers to an average depth of 70 cm. The stocks of soil total carbon and nitrogen were also determined. Changes in the carbon-to-phosphorus (C:P) and carbon-to-nitrogen (C:N) ratios of soil can affect the mineralization of soil organic matter and thus the release of nutrients for use by organisms. In addition, oxalate-extractable aluminium and iron, representing the concentrations of aluminium and iron oxides, were determined from the samples. Stocks were calculated using the equivalent soil mass (ESM) method, which quantifies stocks in terms of soil mass layers rather than depth layers. The differences in the concentrations and total stocks of the investigated forms of phosphorus between management systems were found to be relatively small. The slight differences in total stocks may indicate that phosphorus fertilization in the cultivated plots has corresponded well with the amount of phosphorus taken up by the crops. However, both conventional and organic plots also showed indications that phosphorus had accumulated in organic form below the plough layer. The use of organic fertilizers on the organically managed plots appeared to maintain the organic carbon content at deeper soil depths, as the carbon concentration of the organically managed plots and the unmanaged grassland with the highest carbon total stock did not differ statistically significantly at depths of 20–30 cm and below 40 cm. In all management systems, approximately one-third of the total phosphorus stock was in organic form. Based on the carbon-to-organic-phosphorus ratios (C:Porg), the soil organic matter in the cultivated plots contained more phosphorus than the unmanaged grassland, which may indicate that more phosphorus net mineralization occurs in the cultivated plots than in the unmanaged grassland.

Some horses experience a problem called free faecal liquid (FFL). The condition is not characterized by classical diarrhoea but by free liquid that is voided separately from the solid part of the faeces. Problems with FFL include irritation and abrasive lesions in the skin in the rear end. No health issues of more severe character are usually present in these horses, apart from preliminary findings indicating a higher risk of colic when compared to horses without FFL. The reason for why horses develop FFL, and its effects on the horse, are unknown as the subject has not been studied much. It has been suggested that one reason could be in how the horses are fed. It has been speculated that haylage could have an impact on the development of FFL. A study was done with the aim to collect information about feeding and management of horses affected with FFL in Sweden and Norway (n = 100), and to compare faecal composition in horses with and without FFL. This particular part of the study focused on the faecal properties. The objective was to compare chemical composition of the faeces of affected and unaffected horses, in order to detect possible reasons for FFL, which could be studied further. The study was performed with three repeated samplings on all horses. Case and control horses were paired and were housed at the same farm and were fed the same forage. The horse owners were collecting faecal samples using a standardized protocol. The variables examined in faecal samples were dry matter (DM), pH, volume of free liquid after centrifugation, sand, osmolality, acetate, propionate, isobutyrate, n-butyrate and total volatile fatty acid (VFA) concentration of the samples. In samples from the first sampling occasion, differences (P < 0.05) between cases and controls were found in concentration of acetate, isobutyrate and total amount of VFA. Tendencies toward differences (0.10 < P > 0.05) were found in the volume of liquid and sand as well as in n-butyrate concentration. At the second sampling tendencies toward differences were found in the amount of sand and in n-butyrate concentration. In samples from the third sampling a tendency toward difference was present for pH value. All values were or tended to be higher for horses with FFL. Also, clear correlations were found between nearly all the variables. The pH value was found to correlate negatively with osmolality and all the VFAs except for isobutyrate where no correlation was found in any of the sampling occasions. Osmolality was also found to correlate positively with all the VFAs. VFAs correlated positively with one another. The results showed a tendency toward difference in n-butyrate concentration and presence of sand in faecal samples when case and control horses were compared, although not with consistency as samples form the third sampling occasion did not follow results from the first and second samplings. As the results were not constant throughout the study, these two variables may not be reliable when trying to find possible reasons for FFL. Almost all the variables were found to correlate with one another, exception being isobutyrate with pH. As butyrate is a major source of energy for horses and important for the health of the equine intestine, this information could be useful in further studies concerning the possible reasons for FFL.

Ruisleipä on keskeinen elintarvike suomalaisten ravitsemuksessa. Sen valmistuksessa käytetään yhä perinteistä juuritaikinaa eli raskia, joka sisältää maitohappobakteereja ja mahdollisesti hiivoja. Ruis sisältää runsaasti fruktaaneja ja lisäksi raskin fermentoinnin aikana muodostuu mannitolia. Fruktaani ja mannitoli imeytyvät huonosti ohutsuolesta, mutta suoliston bakteerit fermentoivat ne nopeasti. Nopeasti fermentoituvat substraatit saattavat aiheuttaa vatsaoireita jopa yli 10 % väestöstä. Opinnäytetyössä tutkittiin erään teollisen raskin fruktaani- ja mannitolimetaboliaa, raskimikrobistoa sekä raskimikrobiston fruktaaninhajottamiskykyä. Tutkimuskohteeksi valittiin BF-raski. BF-raskin fruktaanin, mannitolin ja pelkistettyjen sokerien pitoisuutta mitattiin raskituksen edetessä. Mittausten jälkeen käyttövalmiista BF-raskista eristettiin maitohappobakteerit ja niiden fruktaanin hajottamiskykyä testattiin kromogeenisillä maljoilla ja puhdasviljelmistä tehdyillä fermentaatioilla. Lisäksi valmistettiin BF-raskin kaltainen spontaani raski pienessä mittakaavassa ja mitattiin sen fruktaanipitoisuutta. Tutkimuksessa havaittiin, että BF-raskin raskitusprosessin aikana fruktaani ja prosessissa syntynyt mannitoli hävisivät. Yhdellä raskin maitohappobakteereista havaittiin olevan kyky kuluttaa tehokkaasti fruktaania ja geenit, jotka koodaavat solunulkoista fruktaanihydrolaasi-entsyymiä sekä FOS/fruktoosi-kuljetussysteemiä. Lisäksi siltä löytyivät mannitolin käyttöön tarvittavat geenit. BF-raskin kaltainen fruktaania kuluttava raskisysteemi saatiin aikaan myös spontaanisti pienemmässä mittakaavassa. Fruktaanivapaan ruisraskin avulla voidaan valmistaa niukasti fruktaania ja mannitolia sisältävää ruisleipää. Tällainen ’vatsaystävällinen’ ruisleipä voisi sopia perinteisestä ruisleivästä vatsaoireita saaville kuluttajille.

The Rosaceae family accounts for more than 90% of the total fresh fruit production in Finland and for more than 25% worldwide in 2013. Thus, improving the yield potential of Rosaceae species works in favor of economic growth and food security. To achieve that, expanding the knowledge on Rosaceae species is required. Fragaria vesca (F. vesca), particularly the everbearing F. vesca semperflorens accession ‘Hawaii-4’ (H4), provides several features that makes it formidable as a model organism for the study of physiological processes in Rosaceae species, where the CENTRORADIALIS/TERMINALFLOWER 1/SELF-PRUNING (CETS) genes play a remarkable role. In this Thesis, I have studied the expression patterns and functions of the CETS genes by performing gene expression analysis, generation of H4 transgenic lines and observation on H4 plants (both transgenic and wild type) grown under different sets of conditions. My results confirmed the expression patterns and functions previously reported for F.vesca TERMINAL FLOWER1 and F.vesca FLOWERING LOCUS T1. I showed that F.vesca CENTRORADIALIS-LIKE2 is a floral repressor and demonstrated that F.vesca FLOWERING LOCUS T3 is a flowering promoter. Additionally, our data suggest that F.vesca MOTHER OF FT is directly related with stolon formation and that F.vesca CENTRORADIALIS-LIKE1 is most likely a floral repressor. This new information could be used in the future to improve the efficiency of Rosaceae crops farming by adapting flowering and vegetative responses and also for breeding more productive Rosaceae crops.

The transition from vegetative growth to flower formation is especially crucial for the reproduction of flowering plants. This transition is controlled through the regulatory activities of a group of genes named as floral meristem identity genes, of which LEAFY (LFY) is thought as the most important one. As a plant-specific transcription factor, LFY controls flower formation and floral patterning, which has been most intensively studied in the model annual plant Arabidopsis. In contrast to the plant architecture and flower morphology in Arabidopsis, Gerbera (Gerbera hybrida), belonging to the large sunflower family (Asteraceae), processes head-like inflorescences with different types of flowers distinct in floral morphs, sex and sometimes coloration. Within the last decades, a number of MADS-box and TCP transcription factor genes have been functionally characterized using stable transgenic plants. Recently, another functional assessment method using virus-induced gene silencing (VIGS) has been developed in Gerbera hybrida. In this study, the expression pattern of GhLFY was analyzed in wild-type Gerbera and TRV-based GhLFY silencing was conducted in two Gerbera cultivars – Terra Regina and Grizzly. It could be concluded that the activity of GhLFY is involved in regulating flower development. In VIGS:GhLFY lines, leaf-like organs emerged in disc flowers and the identity of stamen and carpel was interrupted. However, further VIGS trials are needed verify the observed phenotypes. At the same time, two potential lfy mutants – Pingpong and Marimbo were analyzed in both phenotype and genotype. These cultivars show phenotypic alteration in inflorescence development and floral organ structures that were distinct from WT Gerbera. Although the expression level of GhLFY did not change among these cultivars, but the GhLFY sequences contained amino acids mutation sites and four missing proline amino acids in Marimbo were detected. The role of these mutation sites need to be further analyzed in later experimental steps.

Constant increase in protein consumption is global trend and can be seen in consumer behavior of Finnish markets. Consumers are interested in replacing meat proteins with plant proteins, and therefore, it is important to develop locally grown-domestic products and invest in local crop research. Due to this, the current study focuses on the domestic vegetable protein (faba bean and oat) texturing by extrusion cooking and on their functionality when included in burgers. The literature section presents an overview of previous studies on extrusion of vegetable proteins and the functionality of textured vegetable proteins (TVP). In the experimental work the research materials were faba bean protein concentrate and oat concentrate with high β-glucan content. The flour concentrates were texturized with high-moisture extrusion, in different mixtures. Mixtures were prepared in the ratio of: 3:1 (FO) and 1:3 (OF) and soy protein concentrate (S) was used as a reference sample. Moisture content and water absorption capability of TVP samples were measured instrumentally. TVPs were later on applied to develop burgers based on a mixture of meat and vegetable sources. Burgers were prepared for instrumental analysis with seven different recipes, where TVP inclusion, water addition and meat content varied. TVP was included in three different percentages: 0, 25 and 50% and water was added in 0, 12.5 and 25%. In relation to TVP inclusion and water addition, the meat content varied between 25-100%. Sample with 100% meat was used as control sample (0-sample) and burgers with S inclusion as reference samples. Samples were analyzed for cooking loss, shear force and texture profile (hardness, fracturability, springi-ness, cohesiveness, gumminess, chewiness and resilience) which was measured with a compression method. Based on the results of the instrumental analysis, five different burger samples were selected and evaluated for sensorial properties (chewiness, biting force, juiciness and pasty mouthfeel). The highest TVP moisture content was in OF and lowest in FO, hence the difference between S and FO was not significant. The highest water absorption was in S and lowest in OF. 25% TVP inclusion in burgers reduced the cooking loss (p<0.05) and 50% inclusion reduced it even more (p<0.05). With 25% TVP inclusion S had higher (p<0.05) cooking loss compared to FO and OF. With 50% TVP inclusion the difference was eliminated. Water addition increased cooking loss significantly (p<0.05) with each type of TVP. The FO and OF inclusion showed to weaken (p<0.05) the textural properties of burgers and reduced (p<0.05) the shear force. The reference sample S was found to maintain the structure similar as from the meat control sample. Water addition, while replacing meat, weakened also the textural properties and shear force in each TVP included sample. Based on the results, the inclusion of FO and OF in burgers reduces the cooking loss compared to the 0-sample and the reference sample S. The texture of burgers became weaker with FO and OF inclusion, however sensory evaluation revealed them to be similar to S included sample. Therefore additional studies focusing on improving the textural properties of these TVPs are needed. Faba bean and oat concentrates with higher protein contents could be needed to obtain a texture closer to meat.

Fusarium proliferatum has recently become a major threat to onion, which is an important food crop for food security and has a significant role in the agricultural sector. This fungus is found causing rots and producing mycotoxin fumonisin that, if ingested, can cause carcinogenic effects in humans and fatal diseases in animals. F. proliferatum has been identified as a pathogen causing rots and wilts in many plants in several countries, and recently some isolates of this pathogen were also found in Finland causing basal rot in onion. Though F. proliferatum has wide adaptability and pathogenicity, there are research gaps on this newly emerging pathogen, which is mostly limited to some specific hosts such as maize. There is a lack of knowledge of its infection mechanisms and mycotoxin production dynamics in onion. This experimental work was conducted at the University of Helsinki, Finland, to study the nature of pathogenicity and toxin gene expression of F. proliferatum in laboratory conditions as a function of time. Spore suspensions of three isolates of F. proliferatum, Fpr047, Fpr049, and Fpr919, were prepared and used as inoculums that were injected into healthy organically grown onions, which were then stored in dark for five weeks. Control bulbs were inoculated with sterile water. Pathogen virulence, based on symptom development, and fungal colonization in the onion tissues were determined at five different time points and the toxin gene expression was determined at three time points. Colonization levels were determined by real-time PCR using primers binding to the intergenic spacer (IGS) region of F. proliferatum. A part of the IGS region of the three isolates was sequenced to study the diversity between the isolates. All the tested isolates were found to be virulent, and they colonized the onions after one week from inoculation. However, the isolate Fpr919 appeared different from the other two in terms of symptom severity. It was more aggressive than the other two, causing disease symptoms earlier and causing more severe rot symptoms in the infected bulbs. It also had nucleotide sequence variations in the IGS region in comparison with the other two isolates, suggesting genetic diversity. No significant differences were observed between the isolates in the fungal colonization levels. Expression of FUM1 gene and a putative virulence gene SIX2-1 was detected by RT-RT-PCR in most of the infected tissue samples. The results obtained signify that F. proliferatum is a pathogen with the potential of producing fumonisin toxin in onion, suggesting the need for further molecular study on this fungus to control the disease and prevent mycotoxin contamination in plant products.

Towards the year 2030 in Finland, sustainability issues will be dominated by climate change, the worsening state of the Baltic Sea, technological and technical development, globalization, the degradation of ecosystem services and increasing energy consumption. At the decision-making level, setting strategic objectives towards the year 2030 should consist of increasing energy efficiency, halting the reduction of biodiversity and changing consumption habits. Furthermore, promoting public transportation, limiting greenhouse gas emissions, increasing the proportion of renewable energy sources and linking climate policy to all sustainable development policies should be targeted in strategic long-term planning. This master’s thesis research was implemented as a Delphi study, a method commonly used in futures research. In a Delphi study the expertise of a chosen panel is utilized to gather information on a given topic. The research aimed at investigating the experts’ views on 1) the most important driving forces – changes and trends – affecting sustainable development towards the year 2030 2) the desirability and probability of different sustainability objectives and 3) recognizing the potential political conflicts brought by these strategies. The Delphi study was carried out during February 2010 – April 2010. It consisted of two rounds. The first round questionnaire was sent 43 experts (response rate 56 %). During the second round the most interesting first round results were completed with qualitative arguments (response rate 50 %). The results were analyzed in the manner that the research issues of most interest were 1) the trends having the most importance towards the year 2030 2) the most desirable strategic objectives with a high probability for political conflicts. The results indicate a high risk for political conflict especially with the targets on halting the reduction of biodiversity and changing consumption habits. These two objectives were considered difficult to grasp and often overruled by economic interests. Changing the current societal system based on continuous growth and consumption would require profound alterations in economy, society and individual values. The results also indicate that energy is a key issue for the coming decades: setting strategic objectives for replacing fossil fuels should be among the top priorities of the Finnish national government. Also, in addition for climate change being an important trend, the deviation of rankings in importance among the panel indicated a possibility for social and economic trends to have unexpected, sudden effects as we move towards the year 2030. These include global poverty and inequality, changing age structures and the sustainability of the Finnish economy.