Browsing by master's degree program "Master's Programme in Agricultural Sciences"

The objective of the experiment was to study how different additives effect on fermentation quality and aerobic stability of maize silage. Three additives and two maturity stages were used in the labo-ratory scale experiment. Maize silage preserved with different additives was compared to control with no additives. The maize (Pioneer, P7326) used in the study was cultivated at the research farm of the Univer-sity of Helsinki in Viikki on growing season 2018. First silages were made on 21st of August 2018 and after 50 days the second silages were made on 10th of October 2018 92 and 142 days after sowing. The treatments were 1) control 2) formic acid 3) mixture of formic acid, sodium formate, propionic acid and sorbic acid 4) mixture of sodium benzoate and potassium sorbate. Chemical com-positon and buffering capacity of the pre-ensiling maize were determined. Fermentation quality of the silages was also determined. In addition aerobic stability of silages was determined by monitoring the temperature change of silages for 12 days with data loggers. Composition of the maize varied by the maturity stage. Dry matter content in the first maturity stage was 211 g/kg and in the second it was 327 g/kg. Content of water soluble carbohydrates (su-gars) was higher in the first maturity stage. Starch content increased in the second maturity stage considerably. Feed preservation succeeded mainly well and pH of silages in both maturity stages were below four. Sugar content of silages treated with formic acid and mixture of acids was very high in the first maturity stage. Lactic acid content of the control and Na-benzoate and K-sorbate silages was higher than other treatments. Na-benzoate and K-sorbate silage in late maturity stage had noticeably higher acetic acid content. In the silages, there were mainly low content of volatile fatty acids (VFA) and butyric acid was not observed. The silages contained lactic acid as well as acetic acid and only low amount of propionic acid. Silages were aerobically stable except silages of two formic acid silos in the first maturity stage and control silos in the second maturity stage. Temperature started to rise in formic acid silages after 10 days and in control silages after five days from exposure to air. Other silages were aerobically stable during the testing period. The maturity stage affected maize composition and thus ensiling characteristics. Composition differences of maize in different maturity stages cause different challenges in terms of preservation. Different preservation treatments affected the intensity of lactic acid fermentation and silage sugar content and the differences were higher in the first maturity stage. Intensity differences of fermenta-tion and differences in acetic acid content may affect aerobic stability. The use of additives tended to improve aerobic stability of the silages at the late stage of maturity.

Tiivistelmä – Referent - Abstract Potato late blight is caused by Phytophthora infestans -fungus and is considered as one of the most destructive potato diseases worldwide. Annually, late blight causes large economical losses and causes destruction as well on leaves and stems as in tubers. Potato late blight can be controlled by fungicides but due the P. infestans genetic flexibility and resistance for fungicides is increasing, the controlling of the disease must me optimized. The current way to prevent late blight in Finland is to spray crops about every 7-10 days. To reduce the risk for resistance the use of pesticides should be reduced, and application times optimized. Application times can be optimized with the help of forecast models. There are forecast models programmed all over the world, but Finland does not have its own model. The aim of the study was to find out if Negative Prognosis (Germany) and Nærstad model (Norway) apply to use in Finland or whether they require calibration for the optimal use. The other aim was to find out what is the lowest dose of fungicide that potato late blight can be prevented. Field experiment was implemented at Potato Research Institute (Petla) in Finland. There were 12 different trial treatments in four replicates including untreated treatment. Year 2023 was a favourable year for P. infestans due the optimal temperature and high relative humidity which led to severe infection. Negative prognosis model was used to decide the start time for the fungicide use and Nærstad model was used in subsequent decision making during growing season. Crops were observed twice a week for late blight symptoms in leaves and stems until untreated plots were completely destructed by P. infestans. After that the plots were harvested and 100 tubers from each plot were gathered for the storage and later tuber blight observations. The rest of the tubers were sorted and used for calculating the yield and starch percentage. Based on the results from field experiment, Negative prognosis model is a good tool to predict the starting time of the spraying but not completely optimal. Both models require further research and calibration for optimal use in Finland. The best results were from the treatments that did not use forecast models in decision making. Optimal starting time of pesticide applications is the key to successful disease control and the substantial number of sprayings does not automatically lead to successful control.

The sunflower family (Asteraceae) is characterized by its unique head-like inflorescence known as a capitulum. The capitula have evolved enormous diversity in size and shapes, and such variability depends upon the inflorescence meristem (IM) patterning. Gerbera hybrida has emerged as one of the model species for the large Asteraceae plant family. Previous studies have reported that the inflorescence architecture of gerbera has both conserved and derived gene regulatory features. So far, several studies have revealed that some genes, which have highly specialized functions in regulating Arabidopsis flower development, are represented by expanded gene families in gerbera and gained new functions at the level of IM. IM determinacy refers to the fate of the meristem to continue growing indefinitely or to terminate into a flower. However, there is still a significant knowledge gap to understand regulation of IM determinacy in Asteraceae. This research aims to explore the expression of the gerbera GSQUA genes and their potential interactions with the key regulators, GhLFY, GRCD2, GRCD7, and GhTFL1, in the patterning of IM of wild-type (WT) gerbera. The study also involved the phenotypic characterization of GhTFL1 overexpression and GhTFL1 RNAi transgenic lines. The results showed that GSQUA2, GSQUA3, and GSQUA7 had similar expression patterns with GhLFY and were expressed throughout the IM and involucral bract, ray, and disc floret primordia. The expression of GSQUA5, which resembles the expression of GRCD2 and GRCD7, started from IM2 and was upregulated throughout the inflorescence development. GRCD6 and GRCD8 exhibited an early and much broader range of expression patterns than the other GSQUAs. Meanwhile, GhTFL1 was expressed only in the shoot apical meristem and IM1. Results from the phenotypic analysis of the GhTFL1 transgenic lines showed that both ectopic and suppressed GhTFL1 expression lines have altered inflorescence architecture. Overexpression of GhTFL1 resulted in the formation of a dome-shaped indeterminate IM, which is not consumed by floral primordia. Severe GhTFL1 RNAi phenotypes show a very small determinate inflorescence that is entirely consumed, with a terminal flower developed at the center. The expression patterns and interaction of GSQUA genes with GhLFY, GRCD2, GRCD7, and GhTFL1 indicated that GSQUA2/3/5/7 are the most promising candidates for regulating IM patterning and determinacy of gerbera. Besides, the findings underscore the crucial role of GhTFL1 in regulating the inflorescence architecture of gerbera and significantly advance our understanding of genetic regulation of IM determinacy in the Asteraceae family.

Kivennäis- ja hivenaineet ovat lypsylehmälle välttämättömiä elintoimintojen ja tuotannon ylläpitoon. Härkäpavun siementä voidaan käyttää valkuaisen lähteenä ja koko kasvustoa säilörehuna, mutta niiden hivenainekoostumusta ei tunneta yhtä hyvin kuin rypsirouheen ja nurmisäilörehun. Tutkimuksessa verrattiin lypsylehmän kivennäis- ja hivenaineiden saantia ja sulavuutta härkäpapusäilörehusta ja härkäpavun siemenestä nurmisäilörehuun ja rypsirouheeseen. Tutkielmassa tarkasteltiin kahta koetta, jotka oli tehty Viikin opetus- ja tutkimustilalla vuosina 2014 ja 2015. Molemmissa kokeissa oli 8 Ayrshire-rotuista lypsylehmää. Kokeet toteutettiin kaksinkertaisina 4x4 latinalaisina neliöinä, joissa oli neljä ruokintaa neljänä kolmen viikon jaksona. Koeasetelmat olivat 2x2 faktoriaalisia. Ensimmäisessä kokeessa faktoreina olivat säilörehun kasvilaji (nurmi tai 1:1 nurmi+härkäpapu-kevätvehnä) ja väkirehun raakavalkuaispitoisuus (175 tai 200 g/kg ka). Toisessa kokeessa faktoreina olivat valkuaistäydennys eri lähteistä (rypsirouhe tai härkäpapu), sekä näiden osittainen korvaaminen Spirulina platensis mikrolevällä. Kokeen 2 koeruokinnat olivat isonitrogeenisiä valkuaisrehujen suhteen. Kokeessa 2 kaikissa koeruokinnoissa oli sama pitoisuus kaupallista kivennäisrehua ja kokeessa 1 kivennäislisä oli täysrehuissa. Härkäpapusäilörehuseos sisälsi enemmän kivennäisaineita, mutta vähemmän hivenaineita kuin nurmisäilörehu. Härkäpavun siemen sisälsi 70 % enemmän kuparia kuin rypsirouhe. Härkäpapusäilörehuseos lisäsi eri kivennäisaineiden saantia 1-6 %, mutta vähensi hivenaineiden, kuten raudan ja mangaanin saantia 5-7 % verrattuna nurmisäilörehuun. Härkäpavun siemen lisäsi kuparin saantia 9 %, mutta pienensi magnesiumin, rikin, raudan, mangaanin ja seleenin saanteja 2-14 % verrattuna rypsirouheeseen. Härkäpavun lisääminen ruokintaan kokoviljasäilörehuna tai kokonaisena siemenenä ei vaikuttanut kivennäis- tai hivenaineiden sulavuuteen. Härkäpapusäilörehu tai härkäpavun siemen eivät eronneet merkittävästi nurmirehusta tai rypsistä hivenaineiden lähteinä. Härkäpapu ei sisältänyt mitään kivennäis- tai hivenainetta haitallisen suurta tai hälyttävän pientä määrää.

Dairy cattle breeding has been driven by economics since the 1930s. For a longer period, the costeffectiveness of dairy farming has been poor, and the farmers have been forced to look for all possible ways to improve economics, through either reducing costs or increasing profit. Finland had in 2018 6250 dairy farms, which all differ from each other by size, economics and production environment. Finland participates to Nordic Cattle Genetic Evaluation (NAV) and uses Nordic Total Merit (NTM) as a joint total merit index for Finland, Denmark and Sweden. It has not been published, whether Finnish dairy farms would need more farm specific total merit indices. Breeding goal preferences do differ not only between farms but also between production types, since organic farmers tend to put more emphasis on production, compared to conventional. The aim of this study was to study whether economic values on breeding goal traits differ between farms and production types. Herd specific economic values were counted for ten breeding goal traits. The study was fulfilled with seven dairy herds, who differed from each other by herd size and production environment. Two of the herds were organic. The calculation of economic values was based on a bioeconomic model SimHerd. It is a stochastic simulation model, which simulates the herd in weekly steps, taking all events in a cow’s life into account. Traits analyzed in this study were chosen according to hypotheses of their economic values. Traits analyzed were ECM yield, mastitis, conception rate of cows, conception rate of heifers, cow mortality, calf mortality, claw and leg diseases, feed efficiency, body weight and other culling. Prices and variable costs as well as the phenotypic data of the farms was collected from the year 2018. Finnish milk production is highly dependent of subsidies, but due to their complexity, only direct subsidies for milk were considered in this study. Relations between traits were cut off from the model before simulation. The maximum number of cows for each farm was set to 1000 to improve the reliability of the simulations. Each trait was simulated three times: with the phenotypic data and then twice with changing the parameter. According to the results, the relative economic value of ECM yield was the highest for all farms. The highest economic values differ between farms, but on average the next highest economic values were for body weight, conception rate of cows and cow mortality. These economic values were in the same range for both conventional and organic farms. When relative economic values are presented as percentages of the sum of standardized economic values, traits affecting longevity cover together the greatest percentage. With improved longevity the cows have more productive years, which means greater lifetime milk yield, less replacement cots and smaller environmental impact. When results were compared between farms, they showed no need for farm specific TMI. A different TMI for organic production would need a further research.

In Finland the evaluation of young Icelandic horses is relatively more common than the evaluation of adults. The goal of this study was to find out about heritabilities and genetic correlations of conformation and movement traits evaluated in young horse linear assessment with horses of age 1-2-year-old. Record data contained the assessment of 354 horses from years 2010-2023. From the assessed traits 18 were selected for calculations. These traits included conformation and movement traits as well as one temperament trait. DMU-program was used to estimate the result using REML-method. Linear model used for all traits contained age, sex, and the assessment event as fixed effects, even though not all of these had statistically significant effect on all traits. Heritability values ranged from 0 to 0,86. For two traits the heritability was zero and only eight traits had a statistically significant heritability value. The genetic correlation was very high between several traits. The average breeding values for eight traits slightly increased over years when observed per birth year. 10 stallions with the most assessed offsprings were selected for further breeding value study. From the breeding values it was possible to observe differences between the stallions. Accuracies of the breeding value estimates were 0,6-0,9 for the traits with higher heritability and 0,3-0,8 for the lower ones, depending on the trait and individual. The results from this study are promising, although it a is bit difficult to compare them to similar previously done studies due to the lack of them and due to the fact that heritability values are tied to the population. It would be good to repeat this study with a bigger dataset to minimize the high standard errors and thus improve the accuracy of the results. The breeding values indicate that information from conformation and movement evaluation from young horses could be used as a tool of selection, but it would be good to first study how the results of young horses are connected to the results from breeding assessment of adult horses.

Tarhaomenapuu (Malus domestica Borkh.) on tärkein Suomessa viljelty hedelmäpuulaji. Omenapuiden jalostus on Suomessa vähäistä ja viljelijät ovat uusien lajikkeiden suhteen pitkälti ulkomaisen jalostuksen varassa. Jos uuden lajikkeen kylmänkestävyyttä pystyttäisiin arvioimaan luotettavasti laboratoriomenetelmin, uusista lajikkeista saataisiin tietoa nopeammin ja edullisemmin kuin kenttäkokeissa, ja viljelijän riski viljelyn epäonnistumisesta pienenisi. Tavoitteena oli selvittää, voidaanko karaistumisen aikana omenan hiilihydraattipitoisuuksissa tapahtuvien muutosten avulla ennustaa lajikkeen kylmänkestävyyttä. Lisäksi tutkittiin silmämääräisen tarkastelun ja ionivuototestin kykyä kuvata lajikkeiden välisiä eroja kylmänkestävyydessä kontrolloidun pakkasaltistuksen jälkeen. Tutkimukseen valittiin etukäteistiedon perusteella kylmänkestävyydeltään neljä erilaista lajiketta: ’Aroma’, ’Lobo’, ’Pirja’ ja ’Santana’. Liukoisten hiilihydraattien kertyminen karaistumisen aikana ei selittänyt lajikkeiden tai kasvinosien välisiä eroja kylmänkestävyydessä. Tärkkelyksen pitoisuus oli sekä versoissa että silmuissa suurempi herkiksi tiedetyillä lajikkeilla ’Aromalla’ ja ’Santanalla’ kuin kestävämmillä lajikkeilla ’Pirjalla’ ja ’Lobolla’. Omenalla suuri tärkkelyspitoisuus karaistumisen aikana saattaa selittää lajikkeiden välisiä eroja kylmänkestävyydessä. Silmämääräinen tarkastelu kontrolloidun pakkasaltistuksen jälkeen kuvasi lajikkeiden välisiä eroja kylmänkestävyydessä sekä versoissa että silmuissa karaistumisen alkuvaihetta lukuun ottamatta. Ionivuototestin erottelukyky versoissa oli heikko. Silmuissa ionivuotesti erotteli lajikkeet syvän karaistumisen aikana. Lisää tutkimusta tarvitaan kasvissa karaistumisen aikana tapahtuvien muutosten tuntemiseksi ja menetelmien kehittämiseksi kylmänkestävyyden mittaamiseen.

Subacute ruminal acidosis (SARA) and ketosis are metabolic diseases that occur in milking cows and affect milk production and feed efficiency. The aim of this thesis was to investigate how milk production and composition of diet and silage affected the occurrence of ruminal acidosis and ketosis in milking cows. Data was provided from six dairy farms with milking robots. From the farms, data was collected from milking test-day results, rumination and performance reports from robot. The farms took samples from silage regularly and feeding plans were updated continuously. Three farms with Gea and three farms with Lely milking robots participated in the study. Data from these farms were collected and sorted in separate Excel-files and analysed with logistic regression analysis to obtain the odds ratios for ruminal acidosis and ketosis and to compare the farms with each other. The odds ratio for ruminal acidosis increased with increasing milk production and concentrate allowance for both Lely- and Gea farms. When dietary and silage crude protein concentration increased the odds ratio for ruminal acidosis decreased in Gea farms but not in Lely farms. An increase in dietary concentrate proportion increased and increase of dietary fibre decreased the odds ratio for acidosis in both farm groups, while an increase of dietary starch and silage fibre increased the odds ratio only in Gea farms. The odds ratio for ketosis decreased when milk production increased in Lely farms. The odds ratio for ketosis increased in Gea farms but decreased in Lely farms when concentrate allowance increased. An increase of dietary starch decreased the odds ratio for Gea-farms but not for Lely-farms. The odds ratio for ketosis decreased for both groups when rumination time increased. There were differences in the odds ratio for ruminal acidosis and ketosis between the farm groups for milk production, rumination time and for various descriptive variables regarding the composition of feeding diet and silage. This suggests that in addition to production level and feeding composition there are other factors influencing the risk of ruminal acidosis and ketosis in farms.

Modern agriculture is based on intensive farming practices where plant production farms rely on external mineral fertilizers and carbon stocks of the soils are decreasing. At the same time, regional clusters of animal production farms are struggling with excessive manure that increases the risk of nutrient leaching from their fields. To overcome problems related to nutrient loss, eu-trophication of watersheds and greenhouse gas emissions from food production, several national projects aim to promote farmers to use recycled fertilizers. The latter are fertilizers or soil condi-tioners which can be processed from side products such as animal manure, green manure, mu-nicipal biowaste, by-products from food industry or sludges from wood industry. The aim of this study was to determine how different recycled fertilizer products affect grain yield and yield quality of oat as well as how the products perform in relation to nitrogen input. The field experiment was founded in southern Finland where oat was cultivated for three successive years in a five-year rotation. Liquid ammonium sulfate, meat and bone meal pellets and biogas sludge were compared with commercial mineral fertilizer. The control treatments were unfertilized plots and mineral fertilization treatments with three different nitrogen levels between 44–161 kg/ha. There were no statistically significant differences between treatments in terms of grain yield, except for favorable growing season 2017 when unfertilized plots produced the lowest yield. Nor were there differences in protein, starch, fiber or ash content of grains among recycled and min-eral fertilizers over the three years. The grain yield was positively correlated with the amount of soluble and total nitrogen. Having the lowest application level, meat and bone meal produced the highest yield per nitrogen input among fertilizer treatments. The yield results show that ammonium sulfate, meat and bone meal and biogas slurry can be as effective as mineral fertilizers in oat production, if they have the same amount of soluble nitro-gen. Good fertility of the research plot and drought stress during the two following years mitigat-ed differences among treatments so that nitrogen fertilization proved itself useful only in the grow-ing season 2017. To gather enough data and determine the long-term effect of recycled fertiliz-ers, further research should be distributed into several pilot farms. Moreover, the current Finnish fertilizer recommendations should be updated towards experimental nutrient balance models. This could encourage farmers to gather information of the yield-limiting factors and prevent over fertili-zation in poorly responsive soils.

The modern food production consumes substantial amounts of fossil energy. Meanwhile, the bioenergy that is embedded in the side streams of food production – such as manure and excess grass biomass, is lost. That energy could be utilized by anaerobic digestion in biogas plants, which would also contribute to an efficient nutrient cycling since the nutrient-rich digestate can be used as a fertilizer. Agroecological symbiosis is a local model for a sustainable food system that is based on the cooperative actions of food production stakeholders around a biogas plant. The aim of this study was to discover what the application of agroecological symbiosis would mean for energy self-sufficiency, nutrient cycling, food production and the structure of agriculture on municipal level. The study subject area was the agricultural area in the municipality of Saltvik on Åland, where grassland for forage and pasture cover 40 % and grains 38 % of the agricultural land area. There are 0,56 livestock units per agricultural hectare. The current state of the food production was modelled based on local farming statistics. Based on that, three scenarios (S1-S3) with increasingly wide modifications were created. In the first scenario (S1), only the digestion of side streams in a biogas plant was added compared to the current system. On the second scenario (S2), 25 % of the agricultural land area devoted to grain production was altered to green manure leys, and in the third scenario (S3) 50 %. The reduction of grain area led to a lower degree of local self-sufficiency of grain feed, which was corrected by reducing the number of animals. The released share of grassland for forage was used for cultivating peas for direct human use. That way the scenarios represented a possible situation, where plant-based food production is increased and animal-based is decreased. The energy self-sufficiency was estimated by the relation of potential bioenergy production and fossil energy use. The rate of energy self-sufficiency rose scenario by scenario, as it was 58 % in S1, 69 % in S2 and 83 % in S3 due to the increased amount of bioenergy produced, as well as the decreased amount of fossil energy used. Simultaneously the portion of recycled nutrients used for fertilization was increased. Compared to the 46 % share of recycled nitrogen in the current system, 5, 9 and 17 percentage units more were used in the S1-S3, respectively. As for phosphorus the corresponding percentage units compared to the original 70 % were 3, 4 and 5 in S1-S3, respectively. The local self-sufficiency of feed remained unchanged and the food production nearly unchanged in each scenario compared to the current state. The study demonstrated the current potential to produce renewable energy in Saltvik based on agricultural side streams to a degree that would cover over half of the current fossil energy use of local food production. By shifting the focus of food production towards plant production, and by expanding the area of green manure furthermore increased the energy and nutrient self-sufficiency.