Browsing by study line "Kasvintuotantotieteet"

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.

Aluminum (Al3+) toxicity is a major limiting factor in acidic soils when pH<5.5 and faba bean experiences yield decreases in these conditions. The multidrug and toxic compound extrusion (MATE) family plays a vital role in Al3+ tolerance across species. This study searched for an ortholog of MtMATE66, a gene involved in Al3+ resistance in barrel medic, in faba bean and quantified the ortholog’s relative expression in 4 faba bean genotypes (GPID_0022, GPID_0153, GPID_0178 and GPID_0191). pBLAST of MtMATE66 in the faba bean unpublished genome identified the ortholog jg20333.t1, with 88.6 % identity, e-value 0.0 and bit score 880. InterPro Scan and NCBI CDD conserved domain queries classified jg20333.t1 as a MATE in the DinF subfamily. MEME Suite identified the 50-amino acid citrate exuding motif characteristic to MATEs exuding citrate in Al3+ tolerance while a multiple sequence alignment and phylogenetic analysis clustered jg20333.t1 with Al3+ -tolerant citrate exuding MATEs. The SWISS Model 3D structure and DeepTMHMM predicted an α-helical, twelve-transmembrane protein topology. The plasma membrane was predicted as the subcellular localisation of jg20333.t1 by ProtComp, WoLFSPORT and YLoc, however SignalP identified no signal peptides. The molecular weight 54.57kDa, theoretical isoelectric point 8.60 and grand average of hydropathicity 0.67 of jg20333.t1 were calculated by ProtParam. EMBOSS Needle and GSDS aligned 13 exons. Four biological replicates of faba bean plants were set up for 3 different treatments: acidic of pH 3.81 (Ac), acidic of pH 3.81 plus Al3+ (Al) and neutral of pH 6.01 (N) in a greenhouse and root tip samples were collected 45 days after transplanting in peat media for RNA extraction. The relative expression of jg20333.t1 was determined by RT-qPCR of jg20333.t1 as target gene, Vfactin as reference gene and N as internal calibrator. The Cq values generated were analysed using the 2-ΔΔCq method and showed high relative fold change in both Ac and Al. The upregulation in Al confirmed the implication of jg20333.t1 in faba bean tolerance to Al3+. The upregulation in Ac suggests upstream regulation by STOP transcription factor. The four genotypes had no significant difference in fold change. Based on these results, it is concluded that jg20333.t1 is a faba bean MATE gene, VfMATE, implicated in Al3+ tolerance by citrate exudation.

Lipoxygenase enzymes, which contribute significantly to storage protein in legume seeds have been reported to cause the emission of volatile compounds associated with the generation of off-flavours. This is an are important factor limiting the acceptance of faba bean (Vicia faba) I foods. This study aimed at using bioinformatic tools to identify seed-borne lipoxygenase (LOX) genes and to design a biological tool using molecular techniques to find changes in sequence in faba bean lines. LOX gene mining by Exonerate sequence comparison on the whole genome sequence of faba bean was used to identify six LOX genes containing Polycystin-1, Lipoxygenase, Alpha-Toxin (PLAT) and/or LH2 LOX domains. Their sequence properties, evolutionary relationships, important conserved LOX motifs and subcellular location were analysed. The LOX gene proteins identified contained 272 – 853 amino acids (aa). The molecular weight ranged from 23.67 kDa in Gene 6 to 96.45 kDA in Gene 1. All the proteins had isoelectric points in the acidic range except Genes 6 and 7 which were alkaline. Only one gene had both LOX conserved domains with aa sequence length similar with that found in soybean and pea LOX genes and isoelectric properties with soybean LOX3. Phylogenetic analysis indicated that the genes were clustered into 9S LOX and 13S LOX types alongside other seed LOX genes in some legumes. Five motifs were found, and sequence analysis showed that three genes (Gene 1, 2 and 3) contained the 38-aa residue motif that includes five histidine residues [His-(X)4-His-(X)4-His-(X)17-His-(X)8-His]. The subcellular localization of the lipoxygenase proteins was predicted to be primarily the cytoplasm and chloroplast. Primers covering ~1.2 kb were designed, based on the conserved region of Genes 1, 2 and 3 nucleotide sequences. Gel electrophoresis showed the PCR amplification of the seed LOX gene at the expected region for twelve faba bean lines. Phylogenetic analysis showed evolutionary divergence among faba bean lines for sequenced and amplified region of their respective seed LOX alleles.

Turnip mosaic virus (TuMV) is an economically important plant RNA virus causing huge damage to wide range of arable and vegetable crops. A study was conducted in Nicotiana benthamiana to know if a TuMV mutant carrying a mutation in a thoroughly conserved WD-domain interacting motif and WG motif in HCPro protein can be mechanically transmitted to a healthy plant or not. HCPRoWD is a mutation in “AELPR” motif where glutamic acid and arginine are replaced by alanine. This mutated virus is here referred as TuMVWD. Similarly, in TuMVAG the tryptophan residue in the WG pair is changed to alanine and this mutated HCPro is called as TuMVAG. Four treatments, TuMVWT (positive control), Mock (negative control), TuMVWD and TuMVAG were made. Three plants per treatment were agroinfiltrated and five plants per treatment were used for mechanical inoculation experiment. Green fluorescent protein (GFP), a quantitative reporter of gene expression, was measured followed by qPCR for quantification of vRNA (viral RNA) accumulation. In agroinfiltrated plants, newly emerged leaves showed strong fluorescence in TuMVWT and TuMVAG by 14 dpi (days post inoculation), but TuMVWD showed poor GFP as compared to TuMVWT. During mechanical inoculation experiment, none of the treatments developed GFP in systemic leaves by six dpi but by 14 dpi GFP accumulation in the upper leaves of TuMVWT and TuMVAG was increased. TuMVWD was not used for 2nd mechanical experiment as it did not cause systemic infection during 1st mechanical inoculation experiment even by 14 dpi. Results from vRNA accumulation showed that mechanical transmission of virus was reduced with TuMVAG and not possible with TuMVWD. However, mutations had negative effect on vRNA accumulation.

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.

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.

Recognizing and evaluating the benefits of trees is important for creating sustainable, safe and recreational urban spaces. i-Tree Eco software is developed by USDA for evaluation and valuation of ecosystem services of urban trees and forests. The objective of this research was to find out how does the quality of collected data affect i-Tree Eco modelling. Two different types of data and modelling results were compared in this research. All trees of the park Kupittaanpuisto in Turku were measured and evaluated according to the i-Tree guidance in late summer 2018 (later inventory). The contrasting data was selected from the tree register maintained by the city of Turku (later tree register). i-Tree Eco models several ecosystem services, of which carbon storage, carbon sequestration, avoided surface water runoff and pollution removal were analyzed in this research. The software estimates the structural value of the trees considering the land use and tree condition as well. The results show that the quality of data affects modelling results. Based on the total inventory data, the amounts of carbon sequestration, avoided surface water runoff and pollution removal were higher than the amounts modelled according to the tree register data. On the other hand, the structural value and carbon storage were bigger based on the register data than on the total inventory measurements. Lack of canopy dimensions and estimates of canopy condition had an impact on the modelling results. According to the total inventory, there were 1315 trees in the Kupittaanpuisto (ca. 34 ha), the structural value was approx. 2 430 000 €, carbon storage was 563 t, annual carbon sequestration 12 t, annual avoided surface water runoff 811 m3 and annual pollution removal 307 kg. On grounds of this research it can be stated that canopy measurements and canopy condition estimates are needed to make more accurate estimates of ecosystem services when using i-Tree Eco. This research showed that trees in the Kupittaanpuisto produce many ecosystem services and the trees are valuable. In the future, the results can be used as a reference for other research projects on ecosystem services of urban trees in the Nordic countries.