Browsing by Subject "Kasvintuotannon biologia"

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  • Mäkilä, Riikka (Helsingfors universitet, 2017)
    The aim of this thesis was to study differences between the yields and stability of grass mixtures and pure stands. In addition, the quality of forage was examined. Timothy cultivars which had different growth rhythms were selected for field experiments. The aim was also to examine how species proportions differ in mixtures between years and harvests and what causes observed variation. Moreover, the effect of the effective temperature sum on the quantity and quality of yield was evaluated. A three year field study was carried out in Jokioisinen and Sotkamo. Plots had either pure timothy stands (Phleum pratense L. cultivars Tuure, Rhonia ja Bor 0301) or mixtures that contained 75% timothy and 25% meadow fescue (Festuca pratensis Huds. cultivars Ilmari ja Klaara). Dry yield (kg ka/ha), D-value, iNDF, NDF, protein and lignin content were determined from each harvest. In addition, botanical composition was analysed in Sotkamo. Grass mixtures had higher dry yields and they were more stable than pure stands. The difference in yileds was more significant in Sotkamo than in Jokioinen. Timothy-meadow fescue growths' NDF and iNDF were closer to desired values than pure stands', but with other quality features weren't discovered advantages. In Sotkamo timothy cultivar's and type's (southern or north) dry yield, D-value, NDF, protein content and botanical composition reacted differently with the effective temperature sum. In Jokioinen the yield and quality of varieties reacted similarly with the effectice temperature sum. All timothy cultivars benefited occasionally from adding a meadow fescue to the mixture but not consistently. Year and harvest affected to the species proportions in the mixtures. Also the effective temperature sum had a correlation with yield and quality. According to the results cultivating grass mixtures instead of pure stands is a good way to achieve bigger dry yields that have high quality.
  • Lahtinen, Leena (Helsingfors universitet, 2017)
    The experiences of an individual build and shape his or her personality. Experiences of nature contribute considerably to the development of children’s self-esteem and self-image. It is worth bearing in mind that the children of today will become the builders and decision-makers of tomorrow and, therefore, their education is of great importance. Their attitudes and values will define the development and well-being of our society. Children’s experiences of their daily lives are a key element of this study. The study explored 5–6-year-old kindergarten children’s (n = 98) experiences of garden activities. The garden was examined as a physical, psychological, social and cognitive environment for growth and learning. The study concentrated on the children’s emotional responses that were aroused by garden activities and on the function of the garden as a social meeting place for children. A further aim of the study was to follow the development of the 5–6-year-old participants’ knowledge of the garden and nature. The children’s experiences were assessed with a drawing task, Me as a Gardener, that was supplemented with individual interviews, conducted between 2014–2015. The children’s emotional experiences and knowledge of nature were enhanced as a result of the garden activities. The activities contributed to an increase in positive experiences and self-image, especially in the case of boys, and to the development of an understanding of the effects of gardening. Based on this study can be expected to, an intentional use of the garden as a growth and learning environment encourages the growth of children in early-childhood education settings.
  • Örö, Nelly (Helsingin yliopisto, 2018)
    Meat and bone meal is a by-product of rendering industry. It contains significant amounts of nutrients, for example 2720 tonnes per year phosphorus in Finland. The use of meat and bone meal in agriculture ceased because of the mad cow disease in 1994. Meat and bone meal has been proved to nearly equal mineral fertilizers both economically and in fertilization effect with many crops. The use of high phosphorus content meat and bone meal as fertilizer decreases the need for non-renewable phosphorus resources and closes food system nutrient cycles. The objectives of this thesis were to consider the suitability of meat and bone meal in potato production and to estimate the recycling potential of meat and bone meal in potato production in Finland. The recycling potential was calculated as a ratio between the annual phosphorus demand in potato production and the amount of phosphorus in meat and bone meal produced in Finland. The mean yields of potato as well as the fertilization rates in agri-environment measures and the plant-available proportion of meat and bone meal were used in calculation. The annual phosphorus demand of potato production was estimated as 1100 tonnes and the amount of plant-available phosphorus in meat and bone meal was estimated as 1630 tonnes. This number includes a category 1 disease risk material which must currently be disposed of. The recycling potentials of meat and bone meal were calculated as 67 % and 74 % for all the material and excluding the category 1 material, respectively. Consequently, the amount of phosphorus in meat and bone meal can supply the demand in potato production. Meat and bone meal is a long-term phosphorus fertilizer and suitable for potato production in Finnish conditions if nitrogen and potassium are supplemented to meet the crop’s demand with other fertilizer products. It’s also an advantage that meat and bone meal is accepted in organic production. In a recycling nutrients point of view, the utilization of meat and bone meal as a fertilizer for instance in potato production is a good opportunity to return nutrients to the agroecosystem’s cycle.
  • Kämäri, Maria (Helsingin yliopisto, 2014)
    Tämän tutkielman tavoitteena on arvioida Suomen luonnonmukaisen maatalouden fosforivirtojen volyymeja, lähteitä ja kohteita sekä virtoihin vaikuttavia tekijöitä. Tuloksia peilataan luomumaataloudelle asetettuun 20 % tavoitteeseen Suomen peltopinta-alasta. Tutkielman käytännön tavoitteena on tutkia, onko ravinteiden kierrätys suomalaisessa luomumaataloudessa riittävän kestävällä tasolla sekä löytää tarvittaessa käyttökelpoisia ratkaisuja luonnonmukaisen maatalouden kestävämpään ravinnetalouteen tulevaisuudessa. Tutkielman aineisto on kerätty BERAS -hankkeen puitteissa seitsemältä suomalaiselta ERA –tilalta (ecological recycling agriculture –tuotantotapa, ERA). Haastatteluaineiston, kansallisten tilastojen ja kirjallisuuden avulla havainnoista koottiin luomutiloja edustavat fosforitaseet ja tilojen sijainnin perusteella rajatun alueen luomutuotantoa edustava SFA -malli. Kolmen vaihtoehtoisen skenaarion ja tuloksien avulla muodostettiin arviot suomalaisen luomumaatalouden fosforitaseista ja -virroista vuonna 2020. Eteläsuomalainen luomumaatalous ei vaikuta hyödyntävän peltomaan fosforivarantoja, vaan turvautuu ostolannoitteisiin ja tavanomaiseen maatalouden tuottamiin ravinteisiin kuten lantaan ja teurasjätteistä valmistettuihin liha- ja luujauhoihin. Koska kotieläintiloja ei ole riittävästi suhteessa kasvinviljelytiloihin, luomumaatalouden lannantuotto ei riitä kasvintuotannon tarpeisiin. Fosforitaseeseen ei saada merkittävää parannusta vuoteen 2020 mennessä, ellei luomumaatalous ala hyödyntämään peltomaan fosforivarantoja. Samanaikaisesti tulee tukea muita kierrättäviä fosforivirtoja, joista tällä hetkellä potentiaalisimpia ovat vesistöjen biomassat. Elintarviketeollisuuden, yhdyskuntajätteiden ym. biomassojen suhteen tulee kehittää uudenlaisia toimintamalleja ja -tapoja, sekä punnita käytön ekologisia, sosiaalisia, taloudellisia ja terveydellisiä näkökulmia. Jos myös tavanomainen maatalous hyödyntää orgaanisia lannoitteita vuonna 2020, kuten hallituksen tavoitteissa on asetettu, orgaanisista lannoitevalmisteista kuten lannasta tulee entistä kysytympää, mikä voi edelleen heijastua eläintiheyteen, luomukasvien satotasoihin ja tuotannon kannattavuuteen.
  • Kämäräinen, Antti (Helsingfors universitet, 2014)
    Street trees are an important part of a comfortable urban environment. Their beneficial effects in the built environment have been documented in a number of ways around the world. In urban environment tree roots are often grown in limited volumes of soil and competing for space with artificial construction materials and technical structures. Low oxygen concentrations in urban soils are considered as one of the major growth limiting factors, particularly under street pavements. The terrestrial growth conditions are difficult to alter in urban environment. By improving below-ground conditions, tree well-being and sustainability can be significantly increased. Increased ensign of growing conditions and the awareness of the value of urban trees have contributed to the creation of landscaping applications such as structural soil. This study compared gas concentrations in the air of structural and conventional soils, used in roadside tree plantings in the City of Helsinki. Soil air samples were collected during growing seasons 2012 and 2013. Proportions of nitrogen, oxygen, carbon dioxide and methane in soil air were determined by a gas chromatograph. CO?-fluxes were used to evaluate the effect of the soil surfacing material to ground ventilation. Structural soil contained more oxygen in all depths compared to conventional tree soil. A strong correlation existed between oxygen and carbon dioxide concentrations. It seems that cobblestone coating with wide seams does not impair the ground ventilation compared to soil covered with cast-iron grate. Atmospheric growth conditions were more favorable in the structural soil; however the oxygen concentrations in conventional soil were also high.
  • Knuutila, Kati (Helsingfors universitet, 2017)
    The soil mineral nitrogen content is affected by many factors such as nitrogen fertilizer, fertilization and cultivated plant species. The effects of these factors on soil mineral nitrogen content were examined and the research was conducted at the Viikki Research Farm during 2013–2015. The possibility of using soil mineral nitrogen content and nitrogen balance to optimise nitrogen fertilization was also studied as well as the leaching of mineral nitrogen during winter and the factors affecting leaching. The soil type of the experimental area was clay loam in topsoil and sandy loam in subsoil. Soil samples were taken in the spring before tillage and in the autumn before soil freezing from topsoil (0-20 cm) and subsoil (30-50 cm). Ammonium and nitrate were extracted from soil samples with 2 M KCl. Plant species and fertilization changed every year, but fertilization followed the regulations for the subsidies of agricultural environment and all the fertilizers and cultivars were commercially available in Finland. The nitrogen content of the seed and forage samples were determined. The actual nitrogen yield and nitrogen balance were calculated. The expected nitrogen yield and nitrogen balance were calculated with the common nitrogen contents of seeds published by the Finnish Agency for Rural Affairs and compared to the actual nitrogen yield and nitrogen balance, but no differences were found. Soil mineral nitrogen content, nitrogen balance and nitrogen yield varied a lot from year to year which was partly caused by the differences between the growing seasons and winters as well as the changes of cultivated plants and fertilization. The soil mineral nitrogen content was smaller in the spring (33 N kg/ha) than in the autumn (55 N kg/ha). Grass took more nitrogen than the other plant species. The soil nitrate content was smaller under growing grass than harvested plant stand in the autumn and the ammonium content was greater under growing grass than other plant species in the spring. The soil mineral nitrogen content was reduced and differences between treatments were moderated during the winter, which was probably caused by leaching. Fertilization had no direct effect on soil mineral nitrogen content. Increasing nitrogen fertilization increased nitrogen balance, but there was no correlation between nitrogen balance and soil mineral nitrogen content.
  • Valin, Marjo (Helsingfors universitet, 2014)
    Suomenlinna is a sea fortress that consists of eight islands and it is a very popular tourist attraction in Helsinki. The vegetation of Suomenlinna has been influenced by its location in the outer archipelago and by the previous military use. The primary aim of this study was to explore the composition and abundance of plant species in soil seed banks of dry meadows at Kustaanmiekka. The established vegetation of the dry meadows was studied in 2009. Soil seed samples were collected in April 2011 from ten dry meadows located around Kustaanmiekka. The samples were taken from two different soil layers: 0-4,5 cm and 4,5-9 cm. Seedling emergence method was chosen to study the seed banks. It was carried out from May to October 2011 in the Viikki campus greenhouse at the University of Helsinki. A total of 5887 seeds from 83 taxa germinated from the soil seed bank samples. The most common species were Berteroa incana (L.) DC., Festuca rubra L. and Potentilla argentea var. argentea. The seed banks contained a few polemochorous species (Berteroa incana, Epilobium hirsutum L. and Silene latifolia Poir. ssp. alba (Mill.) Greuter & Burdet which were brought in Finland with military troops. Noteworthy species found only in the seed bank were Descurainia sophia (L.) Webb ex Prantl and Matricaria recutita L.. The seed density varied from 5030 to17600 seeds/m2. Compared to the short-lived species, the amount of perennial species and their seeds was greater in the seed banks. The number of species and seeds differed between the dry meadows. A 2 luonnonalue had the highest number of species while Makeavesialtaiden luonnonalue and Kustaanmiekan sisäosan hiekkataso had the highest number of seeds. The total number of species and the average number of seeds didn´t correlate with the content of the main nutrients or humus in the soil, nor with soil pH or soil type. The soil seed banks could be utilized in the maintenance of the dry meadows in Kustaanmiekka by uncovering and breaking the soil. Rare meadow species that reproduce from seeds and that are still present in the vegetation would also benefit from this. More research is needed to determine the best method to utilize the soil seed banks when seeking to recruit as many species from the seed bank as possible.
  • Niemelä, Aki (Helsingfors universitet, 2016)
    Atmospheric concentration of greenhouse gases has increased significantly since the pre-industrial era. Global warming is a major issue in the modern world and it has been predicted that climate will change dramatically in the next few decades due to the growing GHG concentrations. Agriculture is a major source of GHG emissions and the EU has set a target for the agricultural sector to reduce GHG emissions. The aim of this study was to calculate GHG emissions for the plant and animal production of studied Finnish farms for the year 2013. The aim was also to analyse the effects of reduced synthetic nitrogen fertilizer use to agricultural GHG emissions with help of two co-operation model for the farms. Another goal was to develop an Excel-based calculator to calculate GHG emissions from farms. Data for this study was collected from 9 actual Finnish farms. The farms were paired and simulated co-operation models were applied. GHG emissions were calculated with developed FarmCALC 2.1 – calculator for the farm pairs before and after co-operation. Co-operation models reduced the GHG emissions from plant production exiting the farms (11–23 %) and pig meat production (13–20 %). But there was no significant effects in milk and beef production. All effects of the co-operation models to the GHG emissions of animal production were based on the changes in feeding and in GHG emissions of feed production. Joint effect of these two were the reason that no changes in GHG emissions of milk and beef production were observed. There was also some uncertainties in calculation method and the method was sensitive to yield changes so there are some uncertainties in calculated GHG emissions. Despite of these uncertainties, results of this study correlate well with previous studies and results were encouraging. It is recommended to study more about the effects of co-operation and reduced synthetic nitrogen fertilizer use to agricultural GHG emission. This study was part of Sustainable Intensification –project, ”Kasvinviljely- ja kotieläintilojen yhteistyö – avain tuotannon kestävään tehostamiseen” (KESTE).
  • Kemppinen, Johanna (Helsingfors universitet, 2017)
    Blackcurrant (Ribes nigrum L.) is a woody plant in cold regions and it adapts well for the Finland’s boreal zone. There were less than 600 companies farming blackcurrant and green currant in 2014 and the acreage was 1449 ha and the level of yield was over 1000 kg/ha. In year 2016, the number of companies were 544 and the acreage was 1435 ha and the level of yield less than 1000 kg/ha. There has been a pressure to reduce the high price of domestic blackcurrant, due to that the inexpensive imported berries have been taken more position in industry. The global warming can be a serious threat for the cultivation of blackcurrant in the future. There is a need for new cultivars of blackcurrant in Finland and the objective of this research was to examine the depth and reversal of on dormancy on various points of time and the resilience of winter. For the results the bud burst was monitored in quantity and temporal on forcing. The processing of release of dormancy in various temperatures and light conditions before the forcing was also included to the research. The cold hardiness was tested in temperatures, which was descending step by step in controlled sub-zero experiment. The results demonstrated that the bud burst was the lowest during the deepest dormancy in OctoberNovember and the largest in February, when the dormancy was already released. ‘Almiai’ and ‘Gagatai’ were the best cultivars, which were able to maintain the dormancy; in first forcing in October, bud burst 0 %. The bud burst was particularly substantial in February and ‘Ben Tron’ the bud burst was even 80 %. In October-November the time elapsed for bud burst was highest and least was in February with average of 10 days. The most optimal temperature in dormancy release was 0 ⁰C. On the cultivar ‘Mikael’ the bud burst was quicken in +18 ⁰C . The longer the processing time was, the shorter was the time for bud burst. The temperatures +12 ⁰C and +18⁰C were too high for dormancy release. In cold hardiness, the cultivars didn’t differ much from each other. The results demonstrate that the cultivars differ from each other in the depth of dormancy and release. ‘Almiai’ and ‘Gagatai’ maintained best their dormancy. These cultivars could be suitable options for farming in Finland. They were also winter hardiness. In the future, there should be breeding of blackcurrant cultivars, which adjust different kind of environments. Additionally, we should discover and breed cultivars, which have good resistant for winter and maintain dormancy, even though the temperatures are varying in winter.
  • Schulz, Torsti (Helsingin yliopisto, 2014)
    In this thesis I study the end of meadow-based agriculture in the village of Nummenpää in the municipality Nurmijärvi from the 19th century to the mid 20th century. My primary source materials are historical maps of the region and the original survey forms of past agricultural censuses. I also appraise the utility of these materials for historical ecological research and the study of long term changes. I digitized agricultural land use from historical maps and analyzed changes in land use by comparing maps from different time periods. The agricultural census records were analyzed with logistic regression to determine characteristics of farms relating to the presence of meadows. Meadows had lost their role in agricultural production in Nummenpää before 1920, somewhat earlier than in Nurmijärvi on average. Between 1870 and 1930 most of the meadows had been ploughed into fields. Of meado land that had been meadow already at the turn of the century only a few percent remained in 1930. Farms in Nummenpää had not yet differentiated into specialized crop production or animal husbandry during the study period, but mechanization proceeded and more emphasis was placed on cattle and dairy production. There was insufficient variability between farms to determine properties that could be associated with the end of the agricultural use of meadows. It is also possible, that meadows lost their role so early that there was no longer a clear link to the agricultural economy. The census records and maps used in the study did not have sufficient temporal coverage and resolution to permit me to determine the dynamics of landscape change associated with the end of the meadow-based agriculture nor the factors driving the change. The separate analysis of map and census data was not conducive to linking socioeconomic change to landscape change. Nonetheless, I maintain that the source materials used in the study, and other similar materials, are well suited for historical ecological research. The materials must be evaluated critically from a historical perspective and the analysis should integrate the distinct sources. By utilizing appropriate spatiotemporal models it should be possible to reach more interesting conclusions and reduce the impact of uncertainty and imprecision inherent in the materials.
  • Andersson, Johanna (Helsingin yliopisto, 2014)
    Bacterial soft rot and blackleg are amongst the major diseases of potato (Solanum tu-berosum L.). In Finland Pectobacterium atrosepticum, Pectobacterium carotovorum subsp. carotovorum, Pectobacterium wasabiae and Dickeya-species cause rotting of the tuber and softening of stems on potato. These diseases cause major postharvest losses and weaken the quality of the crop, which is a problem in seed potato production. The aim of this study was to determine whether the antagonistic bacteria are toxic to in vitro plants, as well as to study the ability of the antagonistic bacteria to spread inside or on the in vitro plants. It was also investigated if the antagonistic bacteria can prevent soft rot of potato in in vitro plants, as well as the ability of the antagonistic bacteria to prevent the spreading of soft rot bacteria from soil to the plants. This study was carried out in laboratory and in greenhouse conditions in the University of Helsinki at the Department of Agricultural Sciences. As potato material cultivar Melody was used and as antagonistic bacteria 10 different bacteria were chosen: Serratia plymuthica A30 (NR), Flavobacterium sp. strain B17 (A3), Agrobacterium sp. (A6), unsequensed bacteria isolated from potato root (A4), Serratia j5h9 (S1), Alcaligenes faecalis (R8), Bacillus M1ju27 (BC1), Bacillus S3H53 (BC2), Burkholderia M1423 (BK3) and Pseudomonas S2h50 (PS3). Dickeya solani and Pectobacterium carotovorum were used as pathogens. Although BC1, BC2, S1 and BK3 antagonists did not influence negatively the potato in vitro seedling growth they did not, however, properly prevent soft rot of in vitro plants. Further studies on preventing soft rot of in vitro plants is needed.
  • Aho, Jenna (Helsingfors universitet, 2017)
    In a previous study, Pectobacterium strains were isolated from rotten potato tubers and stems. Strains were identified as P. carotovorum subspecies carotovorum by their biochemical properties. In acnA gene sequence analysis the strains isolated from diseased potato stems were different from P. carotovorum subspecies carotovorum type strain and also from strains isolated from rotten potato tubers. However, the strains isolated from rotten potato stems were not able to cause typical blackleg symptoms, like rotting of stems, when inoculated in potato plants. The focus of this master’s thesis was to further study if the new strains are pathogenic in nature or whether they could have arrived to already rotten potato tissue as secondary infection. One goal was to find out if the strains can produce compounds that inhibit growth of known blackleg pathogens, and could they make already contaminated potatoes disease free in a field. This was tested in vitro as well as in a field trial with two potato varieties. As a result the strains isolated from stems were able to produce toxic compounds that inhibited the growth of several common soft rot and blackleg pathogens, whereas compounds produced by the strains isolated from tubers had no effect on the growth of the other bacteria. This suggests that the strains present in stems have properties that make it possible for them to spread from the environment to already infected stem lesions and compete with blackleg and soft rot bacteria already present in the tissue. Blackleg symptoms were absent during the field trial, but in some cases the inoculations caused soft rot of tubers and stunted growth of the inoculated plants. The two potato varieties used in the field trial, Rikea and Fontane, had a different response against the used strains. Although the in vitro results suggested that some of the strains that were originally isolated from stems could act as biological control agents, the results from the field trial contradicted this indicating that the strains might have pathogenic properties, which makes them unsuitable as biological control organisms.
  • Kotkavuori, Juulia (Helsingfors universitet, 2016)
    The common lilac is one of the oldest cultivated ornamentals in Finland. The basic form of common lilac spread here in the beginning of the 18th century and lilac cultivars came in the mid-19th century. The aim of this study was to create DNA fingerprints for selected un-named common lilac individuals found in parks of Helsinki. The second objective was to find out the spread and cultivation history of common lilac in Finland. The hypothesis was that the common lilac was introduced and dispersed via Turku and Viapori. This was tested by comparing the DNA fingerprints of old lilac shrubs growing in historical sites with each other. DNA fingerprints were created for 88 samples using nine microsatellite markers The diversity of the microsatellite markers and the lilacs were evaluated by the effective number of alleles, expected heterozygosity and PIC values and AMOVA, respectively. Cluster analysis and a UPGMA dendrogram allowed the detection of identical samples. A total of 35 alleles were found and each of the nine loci was polymorphic. The effective number of alleles ranged from 1.17 to 4.83. The expected heterozygosity ranged from 0.14 to 0.79. The markers SV2, SV4 and SV1 had the highest PIC-values, more than 0.5. The analysis of molecular variance (AMOVA) showed significant level of differentiation between the clustered groups. The variation is explained by differences between and among the groups. The common lilac material studied was diverse. Microsatellite markers proved to be suitable for the study of Syringa vulgaris –species. Cultivar identification was complicated by missing amplification products. One local shrub was identified as the old French cultivar 'Congo'. The samples from historical sites connected to Turku and Viapori did not show any consistent differences, so the data do not support the hypothesis of two old lilac populations.
  • Laine, Ida (Helsingin yliopisto, 2015)
    Pihlajalla (Sorbus aucuparia L.) on vankat perinteet suomalaisessa maisemassa niin suosituimpana pihapuuna kuin puistoissa ja viherrakentamisessakin. Se on vaatimaton ja kestävä laji, joka kasvaa lähes missä vain ja valtaa nopeasti alaa vesojensa ja siementensä avulla. Metsätaloudellisesti sitä pidetään yleensä roskapuuna. Pihlajasta on jalostettu myös marjantuotantoon sopivia lajikkeita, makeapihlajia. Pihlajan taudeista tiedetään melko vähän, sillä se ei lajina ole taloudellisesti kovin merkittävä. Sen tiedetään sietävän hyvin latvuston ja juuriston tuhoja. Kuitenkin jo 50-luvulta lähtien on ympäri Eurooppaa raportoitu kloroottisista rengaslaikkuoireista pihlajan lehdissä, ja oireiden on todettu siirtyvän oksastuksessa sairaasta kasvista terveeseen. Vasta 2000-luvulla oireiden aiheuttajaksi varmistui aiemmin tuntematon, neljästä yksijuosteisesta RNA-rihmasta koostuva pihlajanrengaslaikkuvirus, EMARAV.Tässä tutkimuksessa haluttiin selvittää löytyykö suomalaisista rengaslaikkuoireisista ja oireettomista pihlajista EMARAV-sekvenssi ja testata RT-PCR:ää sekä dot blot -hybridisaatiota viruksen tunnistamisessa.Eri puolilta Suomea kesäkuussa 2007 kerätyistä 73 lehtinäytteestä jokainen antoi positiivisen tuloksen dot blot -hybridisaatiossa. Näistä 17 näytettä oli peräisin täysin oireettomista puista. RT-PCR:ssä virussekvenssiä saatiin monistetuksi 54 näytteestä. Ongelmia aiheuttivat eristettyjen RNA-näytteiden epäpuhtaudet.Tulosten mukaan EMARAV on Suomessa erittäin yleinen virus pihlajalla ja esiintyy yleisesti myös latenttina infektiona.
  • Laamanen, Tuija-Liina (Helsingfors universitet, 2015)
    Carrot production is very specialized and professional in Finland. Long term storage of the yield is necessary during winter. In storage, the resistance of carrots to diseases decreases even with optimized storage conditions. Diseases can cause huge losses during long storage periods, but the severity of losses varies between years and fields. One of the most harmful diseases of carrots during storage is Mycocentrospora acerina. It is a soil borne fungus that cannot be controlled by fungicides. This is a study of the test method to evaluate the risk of M. acerina in a field. In this test slices of carrots were placed in a container with collected soil samples from a test field. The containers with soil samples and carrot slices were kept six weeks in the dark at +15 °C temperature. After that it was possible to see if M. acerina had grown up from the soil and infected the carrots by forming dark colored patches to the carrot slices. By calculating and comparing the amount of patches on each soil sample it was possible to evaluate the risk of M. acerina in a test field. Results from the test were compared to amount of M. acerina infection found in stored carrots harvested from the same fields. The study showed that it is possible to evaluate the risk of M. acerina. Soil samples can be collected in different times of the year, and the test can be made with fresh or storage carrots. The test samples need to be comparable, so they must be collected the same way and the amount of samples in each container must be sufficient to minimize variation. This study will introduce simple guidelines that farmers can use to test fields and evaluate the risk of M. acerina.
  • Kivivirta, Kimmo (Helsingfors universitet, 2016)
    Elintarvikeväärennösten havaitsemiseen käytetään DNA-pohjaisia tunnistusmenetelmiä. DNA-viivakoodaus on tunnistusmenetelmä, jolla pystytään toteamaan laji tuntemattomasta näytteestä lyhyen DNA-jakson eli viivakoodin perusteella. Tämänhetkiset viivakoodit kasveilla sisältävät nukleotiditasolla vähän lajien välisiä eroja, mikä heikentää näytteiden erottelukykyä ja näytteen oikeaa tunnistamista. Viivakoodien erottelukykyä arvioitiin eri puolukoiden (Vaccinium) suvun lajien kesken. Arviointi tehtiin viivakoodeista matK, ycf1, rpoC1 ja ITS. Puolukoiden suvulle ei löydetty viivakoodia, joka kykenisi tunnistamaan täydellisesti näytteitä lajitasolla. Kloroplastiset viivakoodit matK ja rpoC1 onnistuivat parhaiten PCR:ssa, monistamisessa ja sekvensoinnissa. Genomisen viivakoodin, ITS:n monistamisessa ilmeni häiriötä näytteissä, joissa oli vähän DNA:ta. Avoin lukukehys ycf1 puuttuu puolukoiden (Vaccinium) suvulta, mikä esti viivakoodin käyttämistä. DNA-viivakoodeista matK kykeni tunnistamaan BLAST-tietokantavertailussa seitsemän 14:sta näytteestä ja BOLD-tietokantavertailussa yhdeksän näytettä 14:sta näytteestä. ITS kykeni tunnistamaan BLAST-tietokantavertailussa kahdeksan näytettä 14:sta näytteestä. ITS:lle ei ollut riittävästi vastaavuuksia BOLD-tietokannassa ja rpoC1:lle ei kummassakaan tietokannassa. Sekvenssilinjauksessa matK ja rpoC1 olivat lajien välillä hyvin samankaltaisia. ITS sisälsi lajien välillä enemmän variaatiota, mutta tietokannoista puuttui vastaavia sekvenssejä, mistä syystä positiivisia tunnistuksia saatiin heikosti. DNA-viivakoodauksessa kasveilla kahden viivakoodin käyttö on edelleen suositeltavaa lajitason tunnistuksen tarkentamiseksi. Reaaliaikaisella PCR:lla (qPCR) pystytään spesifisesti toteamaan lajin läsnäolo näytteessä havaitsemalla DNA-jaksoja, jotka ovat ainutlaatuisia kohdelajin perimässä. Spesifinen tunnistusmenetelmä pyrittiin luomaan mustikalle (Vaccinium myrtillus) sijoittamalla alukkeet ja koetin lokuksille dfr ja MADS-box. Mustikan spesifisen menetelmän kehittelyssä ei saavutettu täydellistä spesifisyyttä. Mustikan lisäksi myös lajit V. praestans, V. smallii ja V. ovalifolium tuottivat positiivisen signaalin dfr-geenille suunnitelluilla alukkeilla ja koettimella. Positiivista ekspressiota tuottaneet lajit sisälsivät oletettavasti samankaltaisen dfr-geenin, jolle mustikalle spesifiset alukkeet ja koetin sitoutuivat. Spesifinen menetelmä kykeni kuitenkin sulkemaan pois muiden kasvisukujen näytteet sekä suurimman osan puolukoiden suvun näytteistä. Menetelmää voidaan hienosäätää kun dfr-geenin sekvenssi saadaan selville positiivisen signaalin antaneista lajeista tai kun muita suuremman muuntelun alueita paljastuu sekvensoinnin tuloksena.
  • Akkanen, Anni-Maija (Helsingfors universitet, 2014)
    Young people are often vulnerable to mental disorders while they are in a sensitive and fragile developmental stage. Mental disorders are becoming more and more common among young people at an alarming rate. It is estimated that one in five young people suffers from some form of mental disorder and would benefit from a treatment. Mental disorders demand different kinds of treatments. Medical treatment is not the only solution and it should be supported by some sort of functional therapy. By medical treatment you can treat the symptom, not the cause of it. Functional therapy is designed to accustom the patient back to the normal daily habits. It helps the patient to adjust to the normal live after a period in hospital. Different kinds of therapies should be motivating and effective in order to achieve the coals. The empowering effects of nature have been utilized in metal health care. Garden activity has been found to have a positive effect on the human experience of self-confidence and on the ability to cope in social contacts. It has been found to relieve aggression and stress as well as to improve attention and maintenance of social relationships. In natural environments the patient can feel from the treatment relationship and forget about his or her patient status for a while. This study focused to therapeutic horticulture and how it affects young people with mental health problems. The study involved young people in Pitkäniemi psychiatric hospital in two different departments. Young people took part in a weekly garden group from May to September. The aim was to find out if garden activities have an effect to the concentration and mood. Young people self-evaluated their ability to concentrate and their mood before and after the horticultural therapy session. The activities in the garden plot and the patients participating in the garden activities were observed. The nurses were interviewed after the study period. Positive results were obtained. Young people felt that they were calmer, happier and refreshed after therapeutic horticulture session and their concentration was increased. Plants were treated with care and the young patients participated in various work without any preconceptions.
  • Kymäläinen, Sonja (Helsingfors universitet, 2016)
    The woodland strawberry (Fragaria vesca) exists almost in the entire Northern Hemisphere. Short daylength and low temperature induce flowering in autumn. Flowering begins in the next growing season when daylength becomes longer and temperature increases. The aim of this study was to find out the critical daylength for flower induction in woodland strawberry genotypes from different latitudes. The aim was to find out differences in vegetative growth, flowering and FT-gene expression between different genotypes in three daylengths. In this study ten different genotypes from different latitudes were used as the plant material. There were three daylength treatments; 12h, 14h and 16h. After six weeks of treatments plants were moved to greenhouse where the daylength was long (18h). In this study the number of stolons and crowns, petiole length, flowering time and the number of inflorescences were observed. In addition RNA was isolated from five genotypes and the expression of FT-gene was determined. The beginning of flowering depended on daylength and genotype. The northern genotypes began to flower soon after all treatments and they also formed more inflorescences than the southern genotypes. The southern genotypes flowered last and only after 12h and 14h treatments. FT-gene expression was noticed only in 16h daylength and the expression was the strongest in southern genotypes which didn´t begin flowering in this treatment. The petiole lengths were shorter in northern genotypes than in southern genotypes. The number of crowns depended on daylength. In 12h daylength there were more crowns than in 16h daylength. On the other hand there weren´t differences in the number of crowns between the genotypes. The critical daylength for flower induction depends on the latitude of the origin. The critical daylength for flower induction was noticed to be over 16h in Norwegian genotypes. The critical daylength for flower induction is over 14h but under 16h in Finnish and Central Europe genotypes. In southern genotypes the critical daylength for flower induction is over 12h but under 14h. Longer daylengths enhance vegetative growth except crown branching.
  • Unnaslahti, Jenna (Helsingfors universitet, 2017)
    Water deficiency limits the growth of cereals and the utilization of nutrients worldwide. In Finland, the problem is lack of rain during vegetative growth in the spring. At that time plants are most sensitive to stresses. Irrigation in spring could improve yields and the utilization of nutrients in cereals. The aim of this study was to investigate whether spring irrigation affects the nitrogen use of spring wheat (Triticum aestivum L. emend Thell ’Amaretto') and what are the possible effective mechanisms. Study was conducted in the greenhouse as a completely randomized split-plot experiment where the main plot was irrigation (0 or 32 mm) and the sub-plot was nitrogen fertilization (0 and 150 kg/ha). The rate of photosynthesis, leaf area index (LAI), stomatal conductance, leaf temperature and SPAD value were measured from the crop. At flowering stage leaf area was measured and the numbers of fertile and sterile flowers were counted and plant nitrogen content was analysed. At maturity stage the yield components and nitrogen content of the grains were determined. The components of nitrogen use of wheat was investigated by calculating nitrogen use efficiency (NUE), uptake efficiency (UPE), utilization efficiency (UTE), agronomic efficiency (AE), grain accumulation efficiency (GAE), internal efficiency (IE), nitrogen harvest index (NHI) as well as nitrogen fertilizer partial factor productivity (PFP) and nitrogen fertilizer recovery (FNR). Biomass production efficiency (BPE) and harvest index (HI) were also calculated. Irrigation increased NUE, UPE and UTE. The NUE of irrigated wheat was 35 whereas the NUE was 25 without irrigation. The increase of NUE due to irrigation was explained for the most part by UTE which was 40 with irrigation and 35 without irrigation. Irrigation increased also the uptake of nitrogen by approximately 20 kg/ha. Additionally, FNR was 60 % and 40 % with and without irrigation, respectively. However, phytomass increased more than nitrogen uptake as a consequence of the irrigation and vegetative mass increased more than grain mass. Furthermore, it was observed that both the photosynthesis and the stomatal conductance became more effective and LAI was higher as a consequence of the irrigation. In conclusion, NUE of wheat can be increased by irrigation. One explanation for this could be that irrigation intensifies netphotosynthesis and stomatal conductivity.
  • Ilomäki, Miika Valtteri (Helsingfors universitet, 2016)
    Ubiquitin is an important modifier in eukaryotic cells through many effects on the targeted protein. Ubiquitination is a reaction cascade, catalyzed by E1 – E2 and finally E3 enzyme which completes the ubiquitination. In this study preselected 61 RING type ubiquitin E3 proteins of Arabidopsis thaliana were classified, grouped and analysed to characterize what kind of domains and groups were included. Proteins which contain a RING domain, can either ubiquitinate substrates independently or function as part of a multi-subunit complex. RING E3s are known to act as a molecular adaptors for the E2s and the substrates. It is the E3 ligase that is responsible for selecting the target protein for ubiquitination and later for degradation in proteasome in to peptides. The same preselected 61 genes were also researched from the Betula pendula Roth genome. Web Apollo database was used to annotate genes from the recently sequenced silver birch genome. As a result 32 gene homologs that included RING domain were identified in silver birch.