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In Finland, potato is cultivated on more than 22 000 hectares, which makes it one of the most important crops. Potato is considered drought sensitivive because of it´s shallow roots. Thus, irrigation is recommended to improve not only the yield but to ensure good tuber quality. However irrigation is increases production costs. Nitrogen fertilization also affects yield and tuber quality but excess nitrogen can increase costs, nutrient leaching and reduce tuber quality. Thus, the equipment that can be used to estimate nutrient deficiencies have become more common. The effect of irrigation and nitrogen fertilization on growth and tuber yield of potato was investigated during 2001 – 2003 at Potato Research Institute in Lammi, Finland. Irrigation methods were surface irrigation and subsurface drip irrigation. Nitrogen was applied as a single dose when planting or as sidedress. Further interest was to find out whether SPAD values could be used to evaluate both the demand and timing of potato nitrogen fertilization. Irrigation did not affect potato development, tuber yield or starch content. Irrigation methods had no effect on tuber yield either. However, irrigation reduced the yield of marketable tuber yield. The benefit of drip irrigation was the possibility of combined irrigation and fertilizer application. Nitrogen increased tuber yield. The potato stand that received nitrogen as a single dose produced the greatest yield. However, even the potato stand which did not receive nitrogen produced quite large yield, over 30 tn/ha. In 2003, the stands which were given sidedress nitrogen with drip irrigation produced even greater yield than the ones that had been given nitrogen as a single dose. The stands which did not receive nitrogen had highest starch content. The SPAD values were used when estimating the demand of nitrogen fertilization with drip irrigation. SPAD measurements are easily conducted and non-destructive. SPAD values can be used to estimate the demand and timing of fertilization, even though there seems to be slight delay until the values indicate the nutrient deficiency.

Ilmaston muuttuessa puiden kasvuolosuhteet muuttuvat lämpötilan ja hiilidioksidipitoisuuden kasvaessa. Vaikka puiden fysiologiset vasteita on tutkittu jo pitkään, tarkempi tieto puiden vuosirytmin muutoksista ja mahdollisista vaikutuksista vuosittaiseen kasvuun on kiinnostavaa. Hiilidioksidin ja lämpötilan vaikutuksia keväiseen lehtien kehitykseen tutkittiin keväällä rauduskoivulla (Betula pendula roth). Tavoitteena oli selvittää tarkemmin silmujen puhkeamisen jälkeistä fotosynteesikapasiteetin kehittymistä ja kohotetun hiilidioksidipitoisuuden ja lämpötilan vaikutusta siihen kaasunvaihtomittausten avulla. Toisena työn tavoitteena on verrata fluoresenssimittauksilla mitattua PSII:n valoreaktioiden maksimitehokkuutta kaasunvaihtomittauksiin. Koe-asetelma toteutettiin kasvihuoneolosuhteissa neljällä eri huoneella. Nykyilmastoa vastaavissa kontrollihuoneissa ilman hiilidioksidipitoisuuden tavoitteeksi asetettiin 380 ppm, ja lämpötila +2 °C ulkolämpötilaan verrattuna. Loppi2100-olosuhteet kuvaavat tulevaisuuden skenaariota, hiilidioksidipitoisuus tasolla 700 ppm ja lämpötila kontrolliin verrattuna +2 °C. Jokaisessa huoneessa kasvatettiin viittä rauduskoivua, joista mitattiin viikoittain kaasunvaihtomittausten avulla mm. hiilen assimilaatiota ja muita fotosynteesiin liittyviä tunnuksia. Eri huoneiden erilaisen lämpötilakehityksen ja eri mittauspäivien takia erot tasattiin laskemalla huonekohtainen lämpösumma, jonka avulla tulokset saatiin vertailukelpoisiksi eri huoneiden välillä. Tulosten mukaan hiilen assimilaatio on suurempaa ja kehittyy nopeammin Loppi2100-olosuhteissa verrattuna kontrolliin. Lämpösumman avulla aineistosta muodostettiin ennustemalli, jonka residuaalien avulla voidaan todeta, että ero käsittelyjen välillä on tilastollisesti merkittävä. PSII:n maksimitehokkuus korreloi kaasunvaihtomittausten tulosten kanssa, vahvistaen käsitystä siitä, että valoreaktioiden tehokkuus antaa hyvän kuvan koko fotosynteesikoneiston kapasiteetista.

The aim of the study was to optimize growth media and its composition for one Lactobacillus strain. The purposes of the optimized culture media for fermentation were to maximize cell count and amount of viable cells during processing. The raw materials for growth media had to be suitable for industrial use. The study was performed by Bioscreen and fermentation tests in different growth media. At first ability of the strain to grow was tested by Bioscreen C with different raw materials and their compositions. According to literature, six carbon, four nitrogen sources and three other raw material were chosen to Bioscreen tests. Bioscreen C measured turbidity (OD value) of cultivation. According to the results from Bioscreen tests, optimal raw materials were chosen to the fermentation tests. The optimal carbon sources were whey permeate powder and glucose, the optimal nitrogen sources casein peptone and yeast extract and other raw materials manganesulfate, magnesiumsulfate and yeast extract. The cultivations were made in a bioreactor (Biostat Q). The starter strains were concentrated and freeze-dried. Samples from cultivated, concentrated and freeze-dried starter strain were analyzed (cell counts, optical density, growth rate, base consumption and survival-%). Results were compared to those obtained using control medium that is known to support the growth of the Lactobacillus strain. Lactobacillus strain was able to grow in different growth media. In Bioscreen tests compositions of growth media have major effect on lactobacilli growth. Bioscreen experiments revealed that in most cases the Lactobacillus strain grew to higher OD values in the composed media compared to control medium. In Bioscreen tests the sugar based growth media required more added minerals and yeast extract than whey permeate based media. Yeast extract was found to promote Lactobacillus growth in Bioscreen tests. In fermentation tests cells grew on growth media equally as on control media. Suitable alternative options for growth media were found from tests for further studies. Further studies can research functionality of the raw materials in production scale and preservation of the cell concentration during storage.

Red raspberry (Rubus idaeus L.) is one of the most important berry crops economically in Finland but the profitability is weakened due to frequent winter injuries and varying yields. Protected berry production has lately become the main cultivation method of raspberries in Europe. Long cane raspberry is a special plant type that has been induced to flower and cold stored to produce a harvest in the year of planting. Specifically designed for protected cropping raspberry long canes have been shown to possess a very high cropping potential. The aim of this study in the first experiment was to examine the effect of growing conditions, primocane and floricane number and storage time on yield of red raspberry long canes. Raspberries were grown in an open field and in a tunnel with varying cane numbers (1 or 2). After cold storage they were forced in a plastic tunnel and new shoots were allowed to grow alongside the floricanes. The canes grown in a tunnel yielded 56 % more compared to those grown outdoors. The plants with two floricanes yielded 39 % more compared to plants with only one floricane but their average berry weight was 0,6 g lower. Presence or absence of primocanes didn’t have an effect on the yield or other growth parameters of the floricanes. In the second experiment plants were grown in an open field and in a tunnel and cold stored for three different periods of 4, 12 or 20 weeks. After storage the plants were forced to flower in a greenhouse. The cropping potential of the plants stored for 20 weeks (977 flowers/plant) was almost three times as high compared to those stored for only 4 weeks (332 flowers/plant). Plants that had been stored for 20 weeks also produced 138 % more laterals that were 14 % longer than plants stored for 4 weeks. Bud break for plants stored for 20 weeks took place 25 days earlier than for those stored for 4 weeks. Carbohydrate content of raspberry cane is related to its ability to produce a harvest. In this experiment the concentration of soluble carbohydrates increased and the concentration of starch decreased during storage. The total carbohydrate content in the whole plant also decreased during storage and it was 12-40 % higher in plants grown in a tunnel compared to the ones grown in an open field. According to this research it is possible to increase raspberry yields with long cane plants. In the two experiments growing conditions and storage time were found to have the biggest influence on cropping potential. The most optimal long cane plant type based on this research would be a plant with two canes that has been grown in a tunnel and cold-stored 20 weeks at the minimum.

This study was conducted to find suitable methods for the quality control of commercial plant growth-promoting (PGP) microbial products. A commercial bacterial product called TwinN was evaluated for its microbiological quality, physiological features of its bacterial strains, and its ability to promote plant growth. Other bacterial strains which had shown PGP features in earlier studies, were used as reference strains. The microbiological composition of the TwinN bacterial lyophilisate corresponded to the manufacturer's description, as it was composed of bacteria belonging to the genera Azoarcus, Azorhizobium, and Azospirillum. However, the concentrations of some of the bacterial species were lower than reported. If the product was used according to the manufacturer's instructions, the bacterial counts in the plants wouldn't necessarily reach a sufficient level. With the TwinN product, a powdery growth medium was also supplied, which appeared to be highly contaminated with bacteria and moulds. The nature and source of these microbes remained unknown. The bacteria in the TwinN product were isolated as pure cultures, and identified based on the partial sequences of their 16S rRNA genes. Specific plate and broth culturing techniques were used to uncover the potential PGP physiological features of the pure cultures. The bacterial strains were able to produce indole-3-acetic acid, ACC deaminase and siderophore, which suggests that they might also have PGP activity. The ability of the bacteria to promote plant growth was tested in a plant experiment using hydroponic growth pouches. An Azospirillum brasilense strain isolated from the TwinN product was able to increase the dry weight of the shoots of chinese gabbage almost 41 % compared with the uninoculated control plants. Of the five bacterial treatments used, the A. brasilense strain was the only one able to promote plant growth. Chinese cabbage was the only plant species out of six that gave a positive response to the A. brasilense treatment. For some reason, the TwinN product itself didn't show any PGP activity. The plants showed signs of nitrogen deficiency, which indicates that no bacterial nitrogen fixation had taken place. The method used to determine the microbial composition of the TwinN product, was Amplicon sequencing. Combined with the results of traditional culturing techniques, Amplicon sequencing proved to be a useful method for the assessment of the microbiological quality of the product. The physiological tests that could be of use in the quality control of PGP products, are siderophore production test, phosphate solubilization test and the test that measures indole-3-acetic acid production.

Tausta: Fosforin saanti on Suomessa kaksin-kolminkertaista suhteessa ravitsemussuosituksiin. Tärkeimmät fosforin lähteet suomalaisilla ovat liha-, maito- ja viljavalmisteet. Elintarvikkeissa luontaisesti esiintyvä fosfori on liittyneenä proteiiniin ja muihin ravintoaineisiin. Kasviperäisissä proteiinin lähteissä fosfori esiintyy fytaattina, jonka hyväksikäytettävyys on pienempi kuin eläinperäisen proteiinin fosforilla. Fosfori on tärkeä ravintoaine, mutta suurissa määrin sillä voi olla haitallisia vaikutuksia elimistössä. Munuaisen vajaatoimintaa sairastavilla veren suuri fosfaattipitoisuus on haitallista ja se on yhdistetty sydän- ja verisuonitauteihin. Vastaavanlainen yhteys on havaittu myös terveillä ihmisillä. Ravinnon fosforin osalta on vähemmän tutkimustuloksia. Fosfaatin ja kalsiumin aineenvaihdunta toimii tiiviisti yhdessä ja niiden säätelyyn osallistuvat mm. lisäkilpirauhashormoni (PTH), fibroblastikasvutekijä 23 (FGF23) ja kalsitrioli (1,25-dihydroksi-D-vitamiini, 1,25(OH)2D). PTH:n ja FGF23:n kohonnut pitoisuus on yhdistetty mm. verisuonien kalkkeutumiseen ja häiriintyneeseen luustoaineenvaihduntaan. Tavoitteet: Työn tavoitteena oli tutkia, onko eläin- ja kasviproteiinipainotteisen ruokavalion välillä eroa fosforin saannissa ja eroavatko ruokavaliot vaikutuksiltaan fosfaattiaineenvaihduntaan. Tutkimushypoteesina oli, että kasviperäinen fosfori imeytyy heikommin kuin eläinperäinen fosfori ja että se aiheuttaa heikomman vasteen fosfaatin aineenvaihdunnan merkkiaineissa. Aineisto ja menetelmät: Tässä tutkimuksessa hyödynnettiin ScenoProt-interventiotutkimuksen aineistoa. Tutkittavia oli yhteensä 136 ja heidät jaettiin kolmeen ruokavalioryhmään: eläinproteiinipainotteinen (eläinperäisen ja kasviperäisen proteiinin suhde 70/30) 50/50-ruokavalio (eläinperäisen ja kasviperäisen proteiinin suhde 50/50) ja kasviproteiinipainotteinen (eläinperäisen ja kasviperäisen proteiinin suhde 30/70). Laskennallinen proteiinin osuus kaikissa ruokavalioissa oli 17E%. Tutkittavat olivat terveitä 20-69-vuotiaita aikuisia (79 % naisia, 21 % miehiä). Intervention kesto oli 12 viikkoa. Ennen intervention alkua ja sen lopussa tutkittavilta kerättiin paastoverinäyte ja vuorokausivirtsa, sekä neljän päivän ruokapäiväkirja. Ravintoaineiden saantia analysointiin AIVODiet-ohjelmalla. Eroja fosforin saannissa intervention loppupisteessä tutkittiin varianssianalyysilla. Fosfaattiaineenvaihduntaan liittyvien merkkiaineiden pitoisuuksia veressä (seerumin kalsium ja fosfaatti, sekä plasman PTH, FGF23 ja 25(OH)D) ja virtsassa (virtsan fosfaatti ja kalsium) intervention loppupisteessä tutkittiin kovarianssianalyysilla käyttäen ennen interventiota mitattuja pitoisuuksia kovariaattina. Tulokset: Alkupisteessä ryhmien välillä ei ollut eroa fosforin saannissa (p>0,05). Intervention lopussa eläinproteiinipainotteisessa ruokavaliossa fosforin saanti oli 1807 mg (SD 506 mg) ja kasviproteiinipainotteisessa ruokavaliossa 1558 mg (SD 320 mg) (p<0,001). Eläinproteiinipainotteisessa ruokavaliossa fosforin eritys (U-Pi) oli intervention lopussa suurempaa kuin kasviproteiinipainotteisessa (p<0,001). Kun fosforin eritys vakioitiin fosforin saannilla, eritys oli edelleen suurempaa eläinproteiinipainotteisessa ruokavaliossa verrattuna kasviproteiinipainotteiseen (p<0,001). Verestä mitatuissa fosfaatti-, kalsium-, PTH-, FGF23 ja 25(OH)D-pitoisuuksissa ei ollut tilastollisesti merkitseviä eroja ruokavalioryhmien välillä intervention lopussa (p>0,05). Plasman PTH-pitoisuus nousi (p≤0,005) ja 25(OH)D-pitoisuus laski (p<0,001) kaikissa ryhmissä. Johtopäätökset: Fosforin saanti ja fosfaatin eritys oli vähäisempää kasviproteiinipainotteisessa ruokavaliossa kuin eläinproteiinipainotteisessa ruokavaliossa. Fosfaattiaineenvaihdunnan verestä mitattujen merkkiaineiden pitoisuuksissa ei havaittu eroa ruokavalioiden välillä. Tulosten perusteella vaikuttaisi siltä, että eläinproteiiniperäinen fosfori saattaa imeytyä tehokkaammin kuin kasviproteiiniperäinen fosfori. Nämä tulokset tukevat aiempia tutkimustuloksia. Jatkotutkimuksia eläin- ja kasviperäisestä fosforista tulisi tehdä erityisesti terveillä koehenkilöillä. Myös fosfaatin aineenvaihduntaa ja sen osallistumista sairauksien kehittymiseen tulisi vielä tutkia lisää.

Loss of biodiversity in the Finnish agricultural environment has increased during the last decades due to the agricultural intensification. Accurate, efficient and repeatable sampling methods are important to follow the impacts of the measures to enhance biodiversity. This study focuses on the assessment of vegetation structure and species diversity. Vegetation cover is one of the most common measures to assess vegetation biodiversity. Cover data is usually collected by a point intercept method, a line intercept method or by visual estimation in quadrats. Traditional methods have been found to be laborious, time-consuming and subjective, and having poor repeatability. The main objective of this study was to find out if it is possible to improve vegetation surveys with digital photographs and an object-based image analysis. To answer this question, a visual method (VM) was compared with a photographic method (PM). The VM was based on ocular estimation of the total vegetation cover. In the PM, pictures of the top cover were taken vertically downward from 1.5 meters above the ground. Using a software program called Definiens, the photographs were divided into segments, which were then classified into bare ground, litter, monocots and dicots to estimate the covers for each category. The data was collected during the summer 2010 from environmental fallows and set-asides. There was a clear correlation between the cover measures in the VM and the PM, so it can be assumed that the PM is suitable for the assessment of the vegetation cover. However, using only the PM, it is not possible to get a reliable estimate of the vegetation structure or species diversity. It was faster to collect the data in the field with the PM than with the VM. The computer used in this survey was inefficient, thus the image analysis took more time than expected and as a result the PM was in its entirety slower than the VM. The study gave important theoretical and practical information about the photographic method, its strengths and weaknesses. Photographic methods are still under development and further research is needed but they hold promise for the future.

The literature review focused on the chemistry, uses, occurrence and toxicology of pesticide residues. Emphasis was placed on residue analytics and GC-MS/MS-methods. The aim of this study was to develop a reliable and reproducible GC-MS/MS-multi residue method for the determination of pesticide residues in poultry feed. First, two available sample preparation methods were compared. The methods chosen for comparison were QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) based on dispersive solid phase extraction (dSPE) and a liquid-liquid extraction method. In the former, the residues were extracted with water-acetonitrile mixture and the content of the dSPE tube containing MgSO4 was added to the extract to induce the liquid-liquid partitioning of the residues. The extract was then cleaned with primary and secondary amine (PSA) and octadecylsilane (C18) absorbents, filtered and analysed by GC-MS/MS. Based on the comparison, the QuEChERS method was chosen for the validation experiments. The QuEChERS method was proven to be a quick and simple method that provided better trueness than the other compared method. The repeatability was sufficient for 54 residue compounds. However, the recovery was between 70-120 % for 28 analytes and mainly less than 70 % for the remaining compounds. The limit of quantification was 0.01 mg/kg for 48 analytes. The developed multi residue method can be used for reliable and reproducible determination of 24 pesticide residues in poultry feed whereas the assessment of the method for the remaining compounds will be continued. After a more comprehensive evaluation, the method can be applied for other feed matrices in future multi residue studies.

Tutkimuksen tavoitteena oli esittää kasvinviljelytilojen yhteisen tuotantoyhtiön toimintamalli ja selvittää, minkälaisia etuja ja haittoja tuotantoyhtiömuotoiseen tuotantoprosessiin siirtyminen aiheuttaa. Lisäksi tutkielmassa selvitettiin olennaisia kysymyksiä tuotantoyhtiön perustamiseen liittyen. Tutkielma koostuu teoriaosasta ja empiirisestä osasta. Teoriaosiossa käsiteltiin aihepiiriin liittyviä käsitteitä, esiteltiin tuotantoyhtiön toimintamalli ja esitettiin suuruuden ekonomian mukanaan tuomat taloudelliset hyödyt. Empiirisessä osiossa tutkittiin tapaustutkimuksen keinoin viittä toiminnassa olevaa tuotantoyhtiötä. Tapaustutkimus suoritettiin teemahaastatteluna ruotsiksi, sillä haastateltavat olivat kaikki äidinkieleltään ruotsinkielisiä. Haastatteluista kolme tehtiin Ruotsissa ja kaksi Suomessa. Tutkittavat tapaukset olivat keskimääräisiä maatalousyrityksiä selvästi suurempia vaihdellen 600 hehtaarista 1000 hehtaariin. Suomessa vuonna 2017 keskimääräinen maatila oli pinta-alaltaan 47 hehtaaria (Luke 2018). Niin kirjallisuudessa kuin teemahaastatteluissa tuli ilmi, että tuotantoyhtiöllä on pystytty alentamaan yksikkökustannuksia. Saavutettu kustannussäästö vaihtelee tilakohtaisesti ja pääsääntönä on, että pienemmät maatilat hyötyvät yhteistyöstä enemmän kuin lähtökohtaisesti suuremmat maatilat. Strategisen yhteistyön, kuten tuotantoyhtiön, huomattiin tuottavan myös sosiaalisia hyötyjä. Sairastapausten sattuessa henkilöriski ei realisoidu täysimääräisesti, sillä useamman henkilön yrityksessä yhden henkilön poissaolo pystytään helpommin korvaamaan kuin yhden henkilön yrityksessä. Lomien järjestäminen on myös helpompaa, kun yhden henkilön merkittävyys yritykselle on suhteessa pienempi. Tuotantoyhtiön haittana voidaan pitää useammasta päättävästä henkilöstä johtuvaa päätöksenteon hidastumista ja yrittäjän kokemusta itsenäisyyden menetyksestä. Haasteltavien käsitys, oliko useampi päätöksentekijä enemmän vahvuus vai heikkous, vaihteli tapauksittain.

Plant proteins have excellent nutritional quality and their use in food is constantly increasing. Plant protein powders are widely used as raw material for plant protein products. Characterization of the sensory properties of plant protein powders is important for product development. Aim of the study was to study the sensory properties of six different plant protein powders using a descriptive analysis. The aim was to obtain new information about the sensory properties of plant pro-teins. Study was conducted during the COVID-19 pandemic. The intensities of the sensory properties of the plant protein concentrates, i.e., faba bean, brown pea, yellow pea, hemp, flaxseed and pea protein isolate were studied by a generic descriptive analysis. The trained panel created a vocabulary for the sensory properties of plant proteins and sensory profile of 17 properties was formed. The profile included six smell, four texture, two flavor, and five taste-related properties together with suitable reference samples. Assessors evaluated the samples in three separate sessions. The results showed that the brown and yellow peas had very similar profiles. Their typical smell properties were grassy, smell and flavor of fresh pea, sweetness, bitterness and mouth-drying sensation. The bitterness and mouth-drying sensation of the faba bean were strongest of all and it also contained more grain and musty smell compared to the peas. The properties of the pea protein isolate differed from brown and yellow peas because in umami taste and pea-like properties. Oilseeds, i.e., hemp and flaxseed were dominated by a grain and musty smell, as well as rough-ness and sandiness. The smell and flavor properties of the cooked peas were mild in the plant pro-tein samples because the properties of cooked peas are created during the production of plant protein products. Due to the high protein concentration of pea protein isolate it differed most from all the other samples.