Browsing by department "Department of Agricultural Sciences"

DRama Queen (DRQ) is an unknown conserved gene that might be involved with sensing cytokinin signalling in the roots of Arabidopsis thaliana. It was originally found in a mutant screen when a mutated version of it – mDRQ – was found to improve the cytokinin sensitivity of plants in a desensitized genetic background. This thesis was done to define the protoxylem phenotype of mDRQ single mutant in Columbia (Col-0) background and to test the functionality of the gene by analyzing the complementation lines. The protoxylem phenotypes were scored from fuchsin stained samples by DIC microscopy. Protoxylem differentiation in the root of A. thaliana is an outcome of a mutually inhibitory signalling mechanism of auxins and cytokinins. Analysis of protoxylem status is a good tool for studying the cytokinin signalling because the differentiation is affected both by increased and reduced signalling levels. High signalling causes loss of protoxylem phenotypes whereas whereas low cytokinin signalling leads to ectopic protoxylem formation. The data of this thesis was analysed by SPSS version 22 software using cumulative logit modelling for the analysis. It was considered to be the most suitable alternative for analysis since the protoxylem phenotype data is ordinal by its nature. A protoxylem phenotype distribution was defined for mDRQ line and it was statistically different from Col-0. Most of the complementation lines were functional at a statistically significant level though the phenotype distributions of the complementation lines were not identical with original background. The difference could possibly be explained by the fact that the mDRQ gene is partially functional and may influence the phenotype distributions.

Food chains have lengthened on account of globalization during the last decades which has led to multiple sustainability concerns related to transport emissions, food security, externalization of environmental costs, consumers’ alienation from agriculture and the origin of food and the economic situation of farmers. Organic and local food, farmers’ markets and community supported agriculture are seen as some ways to enhance the sustainability of the food system. Globally, there is in abundance research about farmers’ markets and their customers. However, there is still relatively little research from Finland about farmers’ markets. In this master’s thesis, the socio-economic and demographic markers of rural event visitors were analyzed to determine their relation to purchasing and event visiting habits. The empirical data were collected through use of a survey administered at a recurrent market event. The results showed that 75.4% of the respondents were female, and that the average age among respondents was 51.8 years. In addition, 63% were living in Hyvinkää, where the event was organized. Domestic origin, price, and healthiness were the most commonly mentioned factors that affected the buying decisions. It was discovered that age had an influence on buying organic, for example, respondents in the age groups 20–29 and 30–39 were buying more organic food compared to other groups, and respondents in age group 70+ less compared to other groups (p=0.003). Income, education, or individual family composition did not affect the tendency to buy organic.

Molecular biology has created a new pathway for plant breeding in cut flower industry. It focuses on studying flower gene functions and provides a more direct and effective way of breeding new flower cultivars using genetic transformation. Besides flower color, disease resistance, quality and vase life, modification of flower architecture is an important target for flower breeding. Previous studies have showed that various transcription factors encoded by the corresponding genes are involved regulating flower development and flower architecture. The most studied are MADS domain and TCP domain transcription factors. For targeted breeding, it is crucial to study the functions of the corresponding genes in detail. For both MADS and TCP domain proteins, previous studies have indicated that protein-protein interactions are important for their function. GhCYC1, GhCYC2, GhCYC3 and GhCYC4, isolated from gerbera (Gerbera hybrida), are CYCLOIDEA –like genes affecting inflorescence development. The protein-protein interactions among these four genes have previously been studied by yeast two-hybrid system. The aim of this thesis was to verify the interactions in living plant cells, using both BiFC and split luciferase assays. Protoplast electroporation and agroinfiltration were used to introduce the genes in planta. The results from the two assays were compared in order to find an effective in planta method for detecting protein-protein interactions. The experiment also provided information about DNA transformation efficiency using protoplast electroporation and agroinfiltration. The results of the split luciferase assay showed that GhCYC1+GhCYC4, GhCYC3+GhCYC4 as well as GhCYC4+GhCYC4 interacted quite strongly in plant cells while GhCYC1+GhCYC1, GhCYC2+GhCYC2 as well as GhCYC4+GhCYC2 had almost no interactions. The interactions between GhCYC3+GhCYC4, and GhCYC4+ GhCYC4 were also shown in yeast two-hybrid, but the other results were different. According to the BiFC assay, no signals of interactions were detected from GhCYC2+GhCYC2, while strong signals were observed from GhCYC2+GhCYC3, and weak signals were seen from GhCYC2+GhCYC4. The interactions between GhCYC2+GhCYC3, GhCYC2+GhCYC4 were also observed in yeast two-hybrid, but the other results were unconfirmed. Large standard deviations were observed in the split luciferase assay and thereby reliable conclusions cannot be drawn from it. However, BiFC turned out to be a better method to detect the protein-protein interactions in planta and clear signals from interactions could be observed. Comparison of the transformation methods indicated that agroinfiltration is a better way of introducing DNA into plant cells than protoplast electroporation. For further study, BiFC assay still needs to be repeated to confirm the efficiency of this assay, and factors affecting the transformation efficiency in protoplast electroporation need to be optimized in the future studies.

Calendula officinalis is grown widely as an ornamental plant across Europe. It belongs to the large. Asteraceae family. In this study, the aim was to explore the possibilities to use Calendula officinalis as a new model organism for flower development and secondary mechanism studies in Asteraceae. Tissue culture of Calendula officinalis was established using nine different cultivars. Murashige & Skoog (MS) medium with four different combinations of plant growth regulators were tested. Of all these combinations, the medium containing 1mg/l BAP, 0.1 mg/l IAA, and 1mg/l Zeatin achieved highest frequency of adventitious shoot regeneration from hypocotyl and cotyledon explants. Virus-induced gene silencing is a recent developed genetic tool for charactering the gene functions in plants, and extends the range of host plants that are not accessible for Agrobacterium transformation. Here, tobacco rattle virus (TRV)-based VIGS technique was tested in calendula (cv. Single Orange). We used TRV carrying Gerbera hybrid phytoene desaturase (PDS) gene fragment to induce PDS silencing in calendula. Vacuum infiltration and syringe infiltration methods both resulted in photo-bleaching phenotypes in leaves, bracts and petals. Loss-of-function phenotypes occurred on calendula 13 days post-infiltration. In conclusion, the data indicates that calendula explants can be regenerated through tissue culture which is a prerequisite for development of stable transformation methods. However, further optimization is still needed to improve the frequency. In addition, VIGS was applied to silence PDS marker gene expression indicating that this method has potential for gene functional studies in future.

The EC regulations for organic farming (OF), No. 834/2007 and 889/2008, apply in all EU countries but still, different rules are being implemented. Every country in the EU has its own certification bodies and certification systems, and the interpretation of the EC regulations for organic farming is done nationally. The purpose of this research is to fill a gap in the understanding how rules of organic farming differ between three countries in Europe: Finland, Sweden and Austria. In particular, this study aims to examine the role of the national interpretations of the EC regulations for OF at different stages in the food supply chain. The main interest lies in why these differences in interpretation occur, and what interpretations are made at what stage in the system. The methods chosen for answering the research questions is a literature review, a survey with qualitative interviews for gathering relevant topics from the field and finally a comparison of the EC regulations for OF and the national legislations and guidelines in Finland, Sweden and Austria for these topics. This study shows that there are many topics in OF where the EC regulations for OF leave room for variable interpretations and hence, it is unclear to the implementing authorities in the member states how to interpret these. The most significant result is that some of the differences in interpretation lead to the organic farmers being unequal across the countries. Even for statements with clear reasoning and precise instructions there can be significant differences in interpretation between the countries. Based on the results of this research I can state that the farmers in OF would benefit from a more harmonized landscape of OF rules on EU-level, as this would lower the inequality between farmers in OF in the different countries. One mean of doing this would be to reduce the number of statements of qualitative character.

This study investigates the effects of oil palm smallholding, wealth, and ecosystem services produced by oil palm dominated agroecosystem in the villages of Tanjung Bering and Betung in Sumatra, Indonesia in 2008. The cultivation of oil palm has many environmental and socio-economic impacts. In particular, indigenous peoples are vulnerable stakeholders between the expanding oil palm plantations. Oil palm industry has sought to find sustainable models for palm oil production: the inclusion of indigenous peoples to oil palm development is an essential part of this. The purpose of the study is to chart the situation and to investigate the impact of the oil palm smallholding for the well-being of local indigenous people, and to provide information for the sustainable decision-making. The study is based on household interviews in the area of the Petalangan ethnic group. The interviews were added to a relational database, which was used to provide variables on ecosystem services, economy and well-being for statistical analysis. Statistical analysis was carried out mainly by cross-tabulating the mentioned variables with wealth and the oil palm smallholding status, significance has been defined with the Pearson’s khii-test. Interpretation and analysis of the results has been made in the framework of ecosystem services by the Millennium Ecosystem Assessment. Oil palm smallholding highly significantly increased households’ income, and wealth increased highly significantly household’s well-being. The fragmented oil palm dominated agroecosystem was still providing ecosystem services to households. The wealth reduced households’ dependency on most ecosystem services as well as substituted many of them. It is concluded based on this study that in the oil palm dominated agroecosystem, oil palm smallholding and higher income affects very favourable to the households’ well-being, and vice versa non-oil-palm-smallholding and poverty predicts ill-being.

The aim of this master’s thesis was to investigate the potential of reducing enteric methane production from dairy cows by replacing barley grain with oat grain on a grass silage-based diet. The effects of grain species on in vitro methane production, digestibility, pH and volatile fatty acid (VFA) production pattern were investigated and a regression analysis was performed to entangle possible methane mitigating mechanisms of oats. The study was conducted in the laboratory at the Department of Agricultural Research for Northern Sweden in the autumn of 2016. An in vitro gas production system was applied, consisting of 16 diets with two replicates, four blanks and three runs, each with a three-day incubation time. The feed material consisted of eight varieties of barley, eight varieties of oats and timothy silage incubated at a grain/silage ratio of 1:1 on a dry matter basis. Rumen fluid was collected from two cannulated Nordic Red dairy cows after morning feeding. Gas sampling was performed at 2, 4, 8, 12, 24, 32 and 48 hours of incubation, meanwhile VFA-sampling, pH-measurements and sampling of incubation residues were performed at 48 hours. Methane production was estimated as predicted in vivo methane production and stoichiometrically predicted methane production. The in vitro digestibility was determined as true dry matter digestibility (TDMD). Content of indigestible neutral detergent fiber (iNDF) was determined by applying a 12-day in situ incubation in two Ayrshire dairy cows. Oats had a higher content of crude protein, neutral detergent fiber (NDF), iNDF and fat compared to barley, whereas barley had a higher content of starch. Replacing barley with oats decreased predicted in vivo methane production by 9% and stoichiometrically predicted methane production by 11%. Variety within grain was not found to have any significant effect on methane production. True DM digestibility and total VFA production were lower in oat-based diets compared to barley-based diets. No significant differences were observed between the diets considering VFA molar proportions. The pH was lower in barley-based diets compared to oat-based diets. True DM digestibility was the best predictor of methane production. Among grain composition parameters, iNDF content was the best predictor of methane production, followed by NDF. Crude fat content also predicted methane production relatively well. Based on the results of this experiment, it can be concluded that replacing barley grain with oat grain in the diet of dairy cows has a potential to lower methane production predicted in vitro. Furthermore, the methane mitigating effect observed in this experiment is at least partly due to the higher fat content and lower digestibility of oats compared to barley.

The application of the split root fertigation (SRF) on strawberry cv. Elsanta (Fragaria × ananassa Duch.) was tested in a greenhouse. Responses of strawberry plants under SRF treatments were evaluated by investigating plant water use, plant vegetative growth, berry yield, and berry quality. In this experiment. Strawberry plants had their roots separated evenly into two parts and grown in containers with two compartments in peat. In the traditional fertigation (TF), the control in the experiment, irrigation water with equal electrical conductivity (EC) (1.4 mS/cm) was applied to both root compartments. Three levels of SRF treatments with low, medium, and high mean EC in irrigation water were designed for the experiment. In these SRF treatments, half of roots received the irrigation solutions with lower EC value of 0.7 mS/cm, the other half of roots received irrigation solutions with EC values of 1.4 mS/cm (SRF1), 2.8 mS/cm (SRF2), and 4.2 mS/cm (SRF3). For plant growth, leaf number, petiole length, runner number and dry weight, plant dry weight, leaf nutrient contents, and flowering date were examined. For yield and berry quality, total fresh yield, total berry number, average berry fresh and dry weight, shelf life, contents of total soluble solids (TSS), titratable acid (TA), total phenolics, and ascorbic acid were measured. For plant water use, substrate water content (?) and EC, leakage amount and EC were recorded; water use efficiency (WUE) and water uptake percentage were calculated to investigate the water use. Compared to TF, plants under SRF treatments showed differences in some parameters. Plants grown under SRF2 had highest total leaf area, although no differences in total plant dry weight were observed; leaf Mg was improved by SRF treatments, leaf N increased by SRF with high EC (SRF3), and leaf B and Mn decreased in SRF with low EC (SRF1). More lateral roots were found of plants under SRF treatment. Plant flowering was accelerated in the medium SRF treatment. For fruit quality, berry size was reduced in SRF3, which was in consistent with the response of strawberry grown under salinity stress. TSS/TA decreased in SRF3. In all SRF treatments, more water was taken up from root compartment with the lower EC value. However, the total water uptake amount had no differences. As a conclusion, SRF treatments affected the plant water uptake distribution, plant vegetative growth, yield and yield quality in some parameters, but results were not consistent in this experiment. Treatments with more EC combinations in a wider range are recommended for further studies.

Andean lupin (Lupinus mutabilis Sweet) is a potential oilseed crop, with a very high protein content (40–45%) and 15–20% oil content. It is valued as an alternative protein source for both human and animal consumption, and like several other lupin species, has a potential role in phytoremediation. Previous experience in central and southern Europe has shown the crop to have low and unstable yields with high sensitivity to heat and drought during the grain–filling stage. The species may therefore be more suitable for cool–temperate climates, as it comes from similar altitudes and latitudes as potato. Therefore, an experiment was set out to quantify the responses of Andean lupin to heat stress, using both gradually and suddenly rising temperatures during grain filling. In preliminary tests 60 accessions from 4 germplasm banks were screened for time to flowering and daylength sensitivity. For this experiment, 3 accessions were chosen, 478435, 457972, 457977, with vegetative phase durations of 44, 53, 64 days from sowing to first flower, respectively. Forty two plants of each accession were sown and reduced to 30 on the basis of uniformity. Plants were grown in a glasshouse with 22 °C, 18 h days and 18 °C, 6 h nights until about 25 days after flowering. Ten plants of each accession were subjected to one of the following treatments: control (continuing in the same glasshouse conditions), sudden heat stress (transferred to a growth chamber and subjected to 38 °C from 11:00 to 15:00) or gradual heat stress (transferred to a growth chamber and subjected to temperature increases of 4 °C day temperature and 2 °C night temperature, with the final two days at 38 °C from 11:00 to 15:00). The plants were returned to the glasshouse and when mature, the seeds were harvested and pooled into 3 replicates per accession and treatment for quality analysis. Seed protein, oil, soluble sugar, ash and moisture content were determined. Data were calculated on the basis of percentage of overall seed mass and also on a milligrams per seed basis in order to reflect the seed physiology at grain–filling stage. Sudden heat stress had greater effects on seed composition than gradual heat stress. When compared with control, sudden heat stress resulted in more loss of every component than gradual heat stress, on a per–seed basis, in all 3 accessions and the responses of the accessions to the sudden stress were not statistically different. Under sudden heat stress, mean seed weight declined by 70%, protein content by 70%, oil content by 85%, ash content by 50%, and soluble sugar content by 75%. The accessions responded differently, however, to the gradual heat stress. Accession 478435 experienced significantly greater reduction in seed weight, protein and ash content than accessions 457972 and 457977. Oil content per seed and soluble sugar content per seed were also lower in 478435 than in the other two cultivars, but the difference was not significant. On the flour basis, sudden heat stress increased ash content and decreased oil content and soluble sugar content significantly in all accessions. Accession 478435 had highest value in ash content at significant level. Under gradual stress, protein and ash content were increased while oil mass and soluble sugar mass were decreased. 478435 had significantly higher protein mass and ash mass in flour with respectively 57% and 5.1%, 457977 had significantly higher soluble sugar content with 112 mg/g. The results showed that heat stress can have a significant effect on the quantity and quality of seed yield in Andean lupin. While all tested accessions were severely susceptible to sudden heat stress, gradual stress identified differences between accessions, with one being much more susceptible than the other two. The most susceptible accession was the earliest to flower. Gradual heat stress allows better resolution than sudden heat stress when screening germplasm for heat tolerance.

Metabolic disorders are known to predispose dairy cows to periparturient diseases. Main components of metabolic disorder are insulin resistance and severe negative energy balance which are responsible for the reduced fertility in addition of increased risk of disease in dairy cows. The mobilization of adipose tissue in response to energy deficiency is associated with metabolic and endocrine changes during early lactation. Reduced insulin sensitivity in peripheral tissues could potentially change the relative rates of lipolysis and lipogenesis. This study focused on expression of lipogenesis and lipolysis associated genes around parturition. Samples and data sets for this study were obtained from the feeding experiments conducted from September 2010 to April 2011 in Viikki Experimental Farm at the University of Helsinki. Sixteen multiparous Ayrshire cows were divided into two groups based on energy level and fibre content of their feed: (1) grass silage group (control) and (2) silage-roughage mixture group (experiment). During experimental period average energy intake (MJ/day) in silage group was 35% higher than in silage-roughage mixture group. Subcutaneous adipose tissue samples were collected a week before, one day and a week after parturition from cows. Total RNA was extracted from tissue samples quality and quantity of total RNA was analysed using electrophoresis and spectrophotometer. Complementary DNA (cDNA) was prepared from the total RNA for quantitative PCR (qPCR). QPCR was conducted to quantitate expression of the following genes: adiponectin (ADIPOQ), leptin (LEP), peroksisome proliferator activated receptor gamma (PPAR-?), adiponectin receptor-1 (AR1), adiponectin receptor-2 (AR2), lipoprotein lipase (LPL), stearoyl-CoA desaturase (SCD) and hormone-sensitive lipase (HSL). Two genes, AR2 and LEP, were downregulated in group 1. Reduced expression of AR2 in group 1 may relate to an increased insulin resistance. The glucose metabolism was reduced further leading to reduced insulin sensitivity. Lower expression of LEP after parturition indicates usage of energy for milk production. The upregulation of SCD in group 1 before and after calving as well as after calving in group 2 may be a result of the uptake of fatty acids by the mammary tissues. The expression of ADIPOQ, AR1, LPL, PPAR, and HSL did not show any significant changes.