Browsing by master's degree program "Maataloustieteiden maisteriohjelma"

With growing consumer interest in the nutritional benefits of high-quality beef, livestock producers face the challenge of enhancing carcass traits, which are typically measurable post-slaughter. As a result, breeding for carcass traits often entails lengthy waiting periods for progeny testing and the need to sacrifice the bull’s progeny for carcass trait assessment. This study aims to estimate the genetic parameters of conformation traits (stature [S], withers width [WW], inner hindquarter [IHQ], hindquarter width [HQW]) and their genetic correlations with carcass traits (carcass weight [CW], carcass conformation [CC], fat class [FC]) using the records of two beef cattle breeds (Charolais: 1,620 and Limousine: 1,326) obtained from the Finnish Animal Breeding Association. A univariate model was used for heritability estimation and a bi-variate model for genetic correlations. The variance and co-variance components were estimated using the restricted maximum likelihood (REML) method in the DMU software. Heritability estimates (±standard error) varied from 0.17±0.04 (FC) to 0.33±0.04 (CC) for Charolais, and from 0.15±0.05 (CW, FC, and WW) to 0.33±0.05 (S) for Limousine. The study found CC to have the highest heritability in both Charolais (0.33±0.04) and Limousine (0.31±0.05) among the carcass traits, indicating a faster response to selection and a higher potential for improvement. Statistically significant correlations were found between conformation and carcass traits, with HQW, IHQ and WW displaying moderate to strong correlations (ranging from 0.32 to 0.79) with CC across both breeds. Additionally, S, HQW and WW exhibited genetic correlations with CW. These results suggest the potential of utilizing these conformation traits as early indicators for the respective carcass traits. These findings offer insights into the potential of using conformation traits as early indicators for selecting animals with desirable carcass traits, thereby guiding breeding decisions towards improved beef quality, as well as promoting resource efficiency.

Long-term, one-sided cultivation of crops has become more common in farming systems in recent decades, but at the same time, it has had negative impacts on soil structure, soil carbon reserves and the biodiversity of farming systems. Pea (Pisum sativum L.) is a legume that can be used to diversify crop rotations and improve protein self-sufficiency. Pea can symbiotically fix nitrogen from the atmosphere with the help of nitrogen-fixing Rhizobium bacteria living in its root nodules, and convert it into usable forms for plants, thus reducing the need to use industrial fertilizers. The following crop may also benefit from the organic nitrogen derived from the pea crop residues and pea’s ability to reduce pest pressure on cereals. The aim of this study was to study the pre-crop effects of pea on the formation of dry matter and nitrogen yields of oat (Avena sativa L.) and rapeseed (Brassica napus L.). The study was conducted as a field experiment in Haltiala with a completely randomized block design in four replicates. The study included four oat treatments (fertilized with 90 kg (N) ha-1 and either oat, pea or pea-rapeseed mixture as a pre-crop, and unfertilized oat with a pea-rapeseed mixture as a pre-crop) and two rapeseed treatments (pea as a pre-crop, unfertilized or fertilized with 90 kg (N) ha-1). In the study, the pre-crop did not affect the amount or formation of dry matter or nitrogen yield of oats and rapeseed. The effect of fertilization on the formation of dry matter and nitrogen yield was also small, but the maximum rates of dry matter accumulation and nitrogen uptake occurred earlier in fertilized than in non-fertilized treatments. Although pea as a pre-crop did not significantly affect the amount of dry matter and nitrogen yield of the crops during the growing season, it did not either affect them negatively compared to the monoculture oat because their yields were similar. Drought in June and July limited the release of nitrogen for plant use, which explains the effect of both the pre-crop and the fertilization treatment being rather small in the dry matter and nitrogen yield of oats and rapeseed. Pea very likely has a positive effect on the growth of the following crop, but further research is needed in different soil types and in more favorable weather conditions.

Karkearehuvaltaisessa ruokinnassa yli puolet lehmien syömästä kuiva-aineesta on peräisin karkearehuista. Suomessa nurmisäilörehuun ja viljaan pohjautuvaa ruokintaa on perinteisesti täydennetty rypsi- ja rapsirehuilla, jotta korkeatuottoisten lypsylehmien ravintoaineiden tarve on saatu tyydytettyä. Herneen (Pisum sativum) siemen on yksi kotimainen täydennysvalkuaisrehuvaihtoehto rypsirouheelle ja -puristeelle. Herneen siemenen valkuaisarvo on huonompi kuin rypsipuristeen tai -rouheen, koska herneen siemenen raakavalkuaispitoisuus on pienempi ja valkuaisen pötsihajoavuus suurempi kuin rypsirouheella tai -puristeella. Tämän tutkielman tarkoituksena oli selvittää, miten rypsipuristeen korvaaminen herneen siemenellä lypsylehmien karkearehuvaltaisessa ruokinnassa vaikuttaa lehmien kuiva-aineen syöntiin, maitotuotokseen ja maidon koostumukseen. Koe tehtiin Helsingin yliopiston Viikin tutkimustilalla 31.3.-25.6.2020 syklisenä jaksokokeena, jossa oli kaksi kuuden ayrshirelehmän blokkia ja kuusi koeruokintaa. Lehmät olivat useamman kerran poikineita ja viimeisimmästä poikimisesta oli kulunut kokeen alkaessa keskimäärin 133 päivää. Koejaksoja oli kolme ja jokainen koejakso kesti 17 päivää, joista päivät 14–17 muodostivat näytteiden keruujakson. Koeruokinnat olivat rypsipuriste tai jauhettu herneen siemen ilman merilevää tai merilevillä A. nodosum tai L. digitata täydennettynä. Koeruokinnasta riippuen rypsipuriste (72 g/kg seosrehun ka) tai herneen siemen (109 g/kg seosrehun ka) annettiin isonitrogeenisenä valkuaistäydennyksenä osana seosrehua. Seosrehussa oli lisäksi 2. sadon nurmi-säilörehua (D-arvo 661 g/kg ka) ja ohraa. Merilevät annettiin erikseen yhdessä kivennäisten ja melassileikkeen kanssa. Koeruokintojen karkearehu-väkirehu-suhde oli 65:35 kuiva-aineessa. Koejaksojen välissä oli 18-päiväinen washout-jakso, jolloin lehmät eivät saaneet merilevää. Koeruokintojen välillä ei havaittu eroa kuiva-aineen syönnissä (22,8 kg ka/pv), mutta rypsipuristeen korvaaminen herneen siemenellä paransi tärkkelyksen saantia sekä vähensi raakavalkuaisen, ohutsuolesta imeytyvän valkuaisen ja kokonaisrasvan saantia tilastollisesti merkittävästi. Lisäksi rypsivalkuaisen korvaaminen hernevalkuaisella vähensi suuntaa-antavasti muuntokelpoisen energian saantia. Laskennallinen pötsin valkuaistase oli kaikilla koeruokinnoilla positiivinen (yli 650 g/pv), mutta herneen siementä saaneiden lehmien pötsin valkuaistase oli tilastollisesti merkittävästi pienempi kuin rypsipuristetta saaneiden lehmien. Herneen siemen paransi suuntaa-antavasti raakavalkuaisen näennäistä kokonaissulavuutta rypsipuristeeseen verrattuna. Myös kuiva-aineen kokonaissulavuus parani, kun rypsipuriste korvattiin herneen siemenellä. Sen sijaan tärkkelyksen ja kokonaisrasvan näennäiset kokonaissulavuudet huononivat herneen siemenen korvatessa rypsipuristetta. Herneen siemen vähensi maitotuotosta tilastollisesti merkittävästi (1,5 kg/pv) sekä rasvatuotosta suuntaa-antavasti rypsipuristeeseen verrattuna. Sen sijaan valkuaistuotokseen koeruokinnalla ei ollut vaikutusta, vaikka maidon valkuaispitoisuus oli herneruokinnoilla tilastollisesti merkittävästi suurempi kuin rypsiruokinnoilla. Maidon rasva- ja laktoosipitoisuuksissa ei koeruokintojen välillä havaittu eroa. Energiakorjattua maitotuotosta tarkasteltaessa erot rypsi- ja herneryhmien välillä tasoittuivat hieman, mutta erot olivat edelleen tilastollisesti merkittäviä (31,2 vs. 30,3 kg/pv, vastaavasti). Vaikka tässä tutkimuksessa herneen siementä saaneiden lehmien maitotuotos oli selvästi pienempi kuin rypsipuristetta saaneiden lehmien, eivät tuotoserot ole selitettävissä ainoastaan täydennysvalkuaisen lähteen vaihdolla. Tutkimuksessa käytetty säilörehu oli sulavuudeltaan heikohkoa, mikä on todennäköisesti vaikuttanut negatiivisesti pötsimikrobien energian saantiin ja sitä kautta mikrobivalkuaisen synteesin tehokkuuteen.

The quantity and quality of buckwheat yield are highly dependent on insect mediated cross-pollination. While buckwheat flowers are visited by a diverse pollinator guild, honey bees are often considered to be their most important pollinators. This study describes the effect of pollination by honey bees and wild pollinators on buckwheat yield quantity and quality (1000 seed weight, harvest index and proportion of empty achenes). The composition of the pollinator guild was also monitored. The study was conducted in Southern Finland, 2017. Pollination cages with four pollination treatments were used to study insect pollination. The treatments were as follows: closed cage with honey bee colony, closed cage (excluding all pollinators), open cage and free pollination. The open cage and free pollination treatments were accessible to both honey bees and wild pollinators. The experiment was conducted as a randomized complete block design with four blocks. A honey bee colony was placed next to the research field to carry out free pollination. Pollinator composition was surveyed by transect walks, with special attention paid to the beginning of flowering, which is when the main yield is formed. The highest yields were obtained in the free pollination (822 kg/ha) and open cage (718 kg/ha) treatments. The yield of plants pollinated exclusively by honey bees was 427 kg/ha. The lowest yield was obtained from closed cages (37 kg/ha). The difference in yield was significant for all treatments except open cage and free pollination. The treatments did not affect the 1000 seed weight. The absence of insect pollination decreased the harvest index by approximately 92% and the proportion of filled seeds by approximately 30 percentage points. At the beginning of flowering, honey bees were the dominant pollinators. Insect pollination is essential for the quantity and quality of buckwheat yield. Pollination service by honey bees increases the yield, but is not solely sufficient. The highest yield was obtained when both honey bees and wild pollinators were present. This study focused on honey bees, but the role and efficiency of specific wild pollinators as pollinators of buckwheat should also be studied.

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.

Couch grass is one of the most common perennial weeds that cause significant yield losses in temperate regions. In conventional farming, glyphosate has been commonly used to control couch grass. As attitudes and regulations are tightening towards the use of herbicides, it is necessary to find effective alternatives to replace herbicides, especially glyphosate. This master’s thesis aimed to examine the efficacy of different mechanical methods to control couch grass. The second aim was to study how these methods affect the spring cereal yield and its quality. The hypothesis was that with mechanical control methods couch grass can be controlled as effectively as with glyphosate. Data was collected from two field trials located in Inkoo and Ruukki in 2020-2021. The study plan included seven treatments: direct drilling, ploughing (in two treatments), tine cultivation, a combination of tine cultivation and ploughing, Kvickfinn cultivator, and fallowing. The coverage of couch grass was visually estimated before tillage and before harvest. Field trials were photographed with drones before harvest. The density of couch grass was defined from direct drilling plots before sowing. Biomass samples of couch grass and barley were collected from every plot for one square meter in Ruukki at harvest timing. Spring barley was harvested, and grain yield and its quality were analyzed. The coverage of couch grass was lower with Kvickfinn and fallowing than with direct drilling in Inkoo. There was no difference in yield and quality between mechanical control methods and direct drilling. In Ruukki the infestation of couch grass was more abundant and more even than in Inkoo. The coverage and biomass of couch grass were highest in direct drilled plots in Ruukki. The yield and quality of spring barley were the lowest and poorest in direct drilled plots. Couch grass was almost totally controlled with fallowing. It has to be taken into account that the results base on the data of only one growing season. Therefore, the long-term effects or the effects of weather are still uncertain. Based on the data, it is possible to conclude that fallowing is the most effective method to control couch grass. It seems that with mechanical control methods, couch grass can be controlled as effectively as with glyphosate. With mechanical control methods the spring cereal yield and quality were better than with direct drilling. It is important to control couch grass because it limits crop growth and yield formation.

Tiivistelmä - Referat – Abstract Acid sulfate soils are formed from sediment deposits containing sulfides, in which sulfur is present in the form of iron sulfides. In contact with air, the sulfur layer initiates a long-chain of biochemical and chemical reactions that increase the acidity of the soil and the amount of sulfate. Excessive acidity restricts plant development and growth. In acid soil, the aluminum solubility reaches a high level of toxicity for roots and slows down the microbiological degradation of organic matters, resulting in a reduction of nitrogen mineralization. Previous research results have shown that important liming has the potential to raise the pH of sulphate soils, and thereby reduce its acidity. With a high pH, the concentrations of ammonium and nitrate in the soil increase, facilitating nitrogen uptake and thereby also improving the efficiency of nitrogen uptake by plants. It has been speculated that, by increasing the nitrogen uptake efficiency and nitrogen utilization in plants, it will improve nitrogen use efficiency and so will reduce denitrification in sulphate soils and the resulting N2O emissions. However, to date, the studies on the effect of liming on plant nitrogen uptake (UPE) and utilization efficiency (UTE) and, consequently, on plant nitrogen utilization efficiency (NUE) have been minimal. The purpose of this study is to investigate how liming affects the yield formation and nitrogen uptake efficiency for barley (Hordeum vulgare L.) in unfertilized and fertilized acid sulfate soils. The field trial was established in Viikki, Helsinki, in the spring 2018. It followed split-plot design, in which the main plots were combinations of plant and nitrogen fertilization treatments (0 or 100 kg of nitrogen per hectare of fertilized barley (Kaarle) or unfertilized fallow) and lime treatments (0; 7,7; 15,3 t/ha) in four replicates. Liming raised the soil pH as expected and also increased nitrogen mineralization during the growing season, which is reflected in the nitrogen uptake. The effect of liming and fertilization on crop formation was small for barley biomass, yield component and grain yield. On the other hand, the liming effect reduced the nitrogen absorption efficiency and the nitrogen utilization efficiency and thereby the efficiency of nitrogen use. Fertilization also increased nitrogen uptake, but also decreased nitrogen utilization efficiency and nitrogen harvest index. The combined effect of liming and fertilization increased nitrogen mineralization. Liming treatment clearly increased nitrogen mineralization more in unfertilized soils than fertilized (there was no difference between liming levels). The drought in June and the low moisture limited the mobilization of nitrogen released from fertilizer in the soil, which would explain the effect of the nitrogen fertilizer treatment remaining relatively small. The drought also limited the development of the roots and thus the uptake of nitrogen and other nutrients. Lime treatment did not change NUE, UPE and UTE, but increased nitrogen mineralization and nitrogen uptake during the growing season, suggesting that under more favorable conditions the liming treatment could improve the efficiency and therefore improve the profitability and ecology of the barley crop. Further studies are needed as the results of studies performed elsewhere may not be valid under boreal conditions.

Maissi (Zea mays L.) on yksi maailman yleisimmistä viljelykasveista. Maissia hyödynnetään maailmanlaajuisesti esimerkiksi ihmisravinnoksi, bioenergian tuotannossa sekä nautakarjan karkearehussa. Rehuna käytetään tuleentunut jyväsato tai koko kasvusto tuleentumattoman korjattuna. Tuleentumattomasta maissisadosta saadaan yhdellä korjuukerralla suurempi kuiva-ainesato kuin muista yksivuotisista rehukasveista tai säilörehunurmista. Runsas yhdellä korjuukerralla korjattava sato on lisännyt viljelijöiden kiinnostusta rehumaissinviljelyä kohtaan. Maissi voidaan kylvää muovista tai muusta katekalvomateriaalista valmistetun katteen alle. Katekalvo luo kasvulle kasvihuonemaiset olosuhteet ja nopeuttaa itämistä ja kasvuunlähtöä. Maissinviljelyä on tutkittu Suomen olosuhteissa vain vähän, joten lisää tutkimusta maissin viljelymenetelmistä tarvitaan. Tämän maisteritutkielman tavoitteena oli selvittää, miten katekalvon käyttö vaikuttaa rehumaissisadon määrään ja laatuun. Kenttäkoe tehtiin Helsingissä kasvukaudella 2018. Koe oli osaruutukoe, jossa pääruututekijä oli kolme korjuuajankohtaa ja osaruututekijänä oli katekalvo (katekalvo, ei katekalvoa). Katekalvon käyttö lisäsi tuore- ja kuiva-ainesadon määrää verrattuna katekalvottomaan käsittelyyn. Katekalvon käyttö lisäsi rehumaissista saatua tuoresatoa keskimäärin 5 tn/ha ja kuiva-ainesatoa (KA-sato) 2,2 tn/ha. Laatuominaisuuksista katekalvon käyttö vaikutti ainoastaan tärkkelyspitoisuuteen. Katekalvon käyttö lisäsi tärkkelyspitoisuutta 40 g/kg KA verrattuna katekalvottomaan. Katekalvon käyttö vaikutti odotetusti sadon määrään mutta ei laatuun. Johtopäätöksenä voidaan todeta, että katekalvon käyttö mahdollistaa runsaamman tuore- ja KA-sadon kuin ilman katekalvoa. Tämän tutkimuksen perusteella katekalvoa voidaan käyttää Suomen olosuhteissa kasvattamaan sadon määrää.

Oats is a major crop in Finland, in one of the most remarkable exporter countries of oats. Oat based value-added products have increased their favor both as healthy domestic foodstuff and as valuable export products. Fusarium head blight infections and mycotoxins accumulated to the oat crops because of the head blight infection pose a serious challenge to the oat production. The head blight infections are predicted to become more common in the future due to the climate change, which increases the need for breeding of new resistant cultivars against the head blight infection. Plant breeding needs more effective and reliable methods to face the challenge. Automatic imaging based high-throughput phenotyping methods can be considered as one possibility to intensify plant breeding. Aim of this master`s thesis was to develop methods for phenotyping oats and head blight infected oat spikelets using RGB- and chlorophyll fluorescence imaging sensors of national plant phenotyping infrastructure in Viikki greenhouses of University of Helsinki. Thesis was carried out as a part of FusNaPPI-project of University of Helsinki and Natural Resources Institute Finland (Luke). Resistant oat genotypes against head blight infection were distinguished, growth and morphology of the oats and progression of the head blight infection were monitored by the developed methods. To reach the goals seven oat genotypes different in head blight resistance were grown and imaged using RGB-sensors during their growth and development. Spikelets were collected from the plants in their flowering phase and were put onto the different in vitro –assays. Spikelets were then inoculated putting the inoculum based on conidia of the F. graminearum inside the spikelets and imaged using chlorophyll fluorescence imaging sensors to detect changes in their photosynthesis in different genotypes and in vitro –assays. Different stages of the head blight infection were seen from the fluorescence data. Decreasing of photosynthetic activity of the spikelet tissues was faster in susceptible genotypes than in resistant ones. Oat genotypes that were different in their morphology in different developmental stages were distinguished in the RGB data. In the experiments, progression of the head blight infection was successfully monitored and the known differences in the disease resistance between oat genotypes were confirmed on the basis of the disease propagation speed. Methods of automatic high-throughput phenotyping as a tools for plant breeding were developed and suitability of these methods for plant`s disease resistance screening were successfully tested.

Hiilen kierto maaperän orgaanisen hiilen (SOC) ja ilmakehän välillä vaikuttaa sekä ilmastoon että maatalouden tuottavuuteen. Orgaaninen aines, johon maaperän hiili pääosin on sitoutunut, on maaperän tuottavuuden perusta. Viljelymaiden maaperän hiilipitoisuuden laskusta on tullut maailmanlaajuinen uhka kasvintuotannon kestävyydelle. Suomalaisilla viljelymailla on raportoitu viime vuosikymmeninä jatkuvaa hiilipitoisuuden laskua. Maaperän hiilipitoisuutta voidaan lisätä erilaisilla kierrätettävistä biomassoista valmistetuilla kierrätyslannoitevalmisteilla. Tämän tutkimuksen tavoitteena oli selvittää, miten neljä erilaista kierrätyslannoitekäsittelyä (biokaasumädätteet, nestelannoite + kuituliete, lihaluujauho, maanparannuskomposti + ammoniumsulfaatti) vaikuttavat maaperän hiilipitoisuuteen ja hiilipitoisuuden muutoksiin verrattuna väkilannoitettuun ja lannoittamattomaan kontrolliin monivuotisessa kenttäkokeessa. Tutkimuksen aineisto saatiin HYKERRYS-hankkeesta (2016–2021) peltokokeesta. Maan kokonaishiilipitoisuuden määritystä varten hyödynnettiin aineistoa, mikä oli kerätty ennen kokeen aloitusta, ennen runsashiilisten maanparannusaineiden ja kompostien levitystä sekä kaksi vuotta maanparannusaineiden ja kompostien levityksen jälkeen. Maanäytteet kerättiin sadonkorjuun jälkeen pintamaasta (maakerros 0-20 cm) maanäytekairoilla. Kokonaishiilipitoisuus oli määritetty vuosina 2016–2018 Variomax CN-analysaattorilla ja vuosina 2019–2021 LECO CN-analysaattorilla. Tulosten perusteella eri kierrätyslannoitekäsittelyllä aikaan saatu maaperän hiilipitoisuuden muutos runsasmultaisella hietasavimaalla ei eroa lannoittamattomasta tai väkilannoitetusta kontrollista. Kierrätyslannoitekäsittelyiden välillä oli tilastollisesti merkitseviä eroja. Nestelannoite + kuitulieteruuduilla oli tilastollisesti merkitsevästi pienempi (8,3–10,8 %) hiilipitoisuus kuin muilla kierrätyslannoiteruuduilla lähtötilanteessa. Lihaluujauhoruutujen hiilipitoisuus oli tilastollisesti merkitsevästi pienempi (12,7–13,8 %) kuin väkilannoiteruuduilla ja nestelannoite + kuitulieteruuduilla 2021. Hiilipitoisuuden nousu viimeisenä vuotena nestelannoite + kuitulieteruuduilla (34 %:n nousu) oli tilastollisesti merkitsevästi suurempi kuin lihaluujauhoruuduilla (3 %:n nousu). Maaperän hiilipitoisuuden nousu viiden vuoden tarkastelujaksolla oli keskimäärin 17,5 % kaikissa koejäsenissä, myös lannoittamattomassa kontrollissa. Kierrätyslannoitteilla ei saatu merkitsevästi kontrolleja suurempaa pitoisuuden nousua aikaan. Tämän aineiston pohjalta ei voida selvittää maanpäällisen ja maanalaisen biomassan vaikutusta maaperän hiilipitoisuuteen, joten lisätutkimusta tarvitaan.