Browsing by discipline "Plant Production Science"
Now showing items 61-80 of 127
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(2017)Perinnebiotoopit ovat perinteisen laidunnuksen ja niiton muovaamia luonnontyyppejä, joiden lajisto on rikas. Karjan laidunnuksen muututtua ja keskityttyä, perinnebiotoopit ovat muuttuneet yhä harvinaisemmiksi. Laiduntaminen on yksi keinoista ylläpitämään perinnebiotooppien monimuotoisuutta ja tuottavuutta. Hevosten määrä etenkin Etelä-Suomessa on noussut huomattavasti. Hevosen laidunnuskäyttäytyminen on kuitenkin valikoivampaa, kun karjalla. Laiduntamisen tärkein tavoite on saavuttaa tyydyttävä eläintuotos, jotta saadaan hevosten omistajat kiinnostumaan riittävän laajasti luonnonlaitumien laiduntamisesta. Tässä tutkimuksessa selvitetään luonnonlaitumella laiduntavien hevosten ravintotarpeiden täyttymistä (kuten energian, sulavan raakavalkuaisen, kivennäis- ja hivenaineiden perustarpeet), luonnonlaitumen sadontuottokykyä sekä laitumien botaanista koostumusta. Luonnonlaitumen eri lohkoilta määritettiin laidunnuskauden aikana kuiva-aineen kertymistä, sadon määrää ja laatua sekä kasvuston botaanista koostumusta. Botaanisen koostumuksen avulla haluttiin selvittää kuinka suuren osan sadosta hevoset syövät. Laitumen kasvustoa suojattiin häkeillä, joita oli 4:llä eri lohkolla. Kaikilla lohkoilla otettiin rehuanalyysinäytteitä sekä laidunnukselta suojatusta, että suojaamattomasta sadosta. Otetut näytteet jaettiin silmämääräisesti syötäviin ja ei syötäviin lajeihin aiempien tutkimusten pohjalta ja punnittiin satomäärien määritystä varten. Näytteet kerättiin yhteensä 9 kertaa kasvukauden aikana. Lisäksi alkukesästä tehtiin botaaninen kasvilajimääritys. Näytteet analysoitiin Valion laboratoriossa NIRS-analyysin avulla. Hevoset saivat energiaa ja valkuaista riittävästi koko laidun kauden ajan. Kivennäisaineiden osalta fosforin päivä saanti jäi suositusarvoja pienemmiksi ja vääristi hevosten Ca:P suhteen liian suureksi. Hivenaineista kuparin ja sinkin saanti ei ollut riittävää. Luonnonlaidun on kivennäislisän kanssa hyvää rehua tyydyttämään hevosen perustarpeet. Luonnonlaitumen ravitsemuksellinen koostumus on viljeltyjä laitumia köyhempi energian ja valkuaisen osalta mikä, vähentää herkästi lihomaan taipuvaisilla hevosilla ylipainosta johtuvia terveysongelmia ja mahdollistaa niiden laiduntamisen.
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(2020)Energiantuotanto perustuu edelleen suurimmaksi osaksi fossiilisten polttoaineiden käyttämiseen. Ilmastonmuutoksen hillitsemiseksi on tarpeellista kehittää uusia, kestäviä energiamuotoja, joita voidaan ottaa tulevaisuudessa laajasti käyttöön. Eräs hyvä vaihtoehto, jota tutkitaan parhaillaan aktiivisesti, on uusiutuvien biomassojen käyttö energiantuotannon raaka-aineena. Maa-artisokka (Helianthus tuberosus L.) on asterikasvien heimoon kuuluva mukulakasvi, jota voidaan viljellä yksivuotisena tai monivuotisena. Maa-artisokan etuja energiakasvina ovat hyvä kylmän ja kuivuuden kestävyys, vähäinen tarve kasvinravinteille, resistenssi useille kasvitaudeille ja -tuholaisille, vähäiset kasvupaikkavaatimukset, nopea kasvu ja hyvä sadontuottokyky. Tutkimuksen tarkoituksena oli selvittää, soveltuvatko maa-artisokan mukulat bioenergian tuotannon mädätteeksi Suomessa, soveltuvatko maa-artisokan versot bioenergian tuotannon kiinteäksi biopolttoaineeksi ja mädätteeksi Suomessa, tuottavatko seoskasvustot yhtä paljon satoa kuin typpilannoitettu puhdaskasvusto ja muodostavatko maa-artisokan jääntimukulat uuden kasvuston. Tutkimus toteutettiin Helsingin yliopiston Viikin opetus- ja tutkimustilalla vuosina 2009 ja 2010. Maa-artisokkaa viljeltiin typpilannoitettuna puhdaskasvustona ja neljänä seoskasvustona eri palkokasvien kanssa. Sadosta tutkittiin maa-artisokan lehtialaindeksi ja kasvuston korkeus, biomassa ja kuivapaino, energiasato, tuhkapitoisuus, hiilen ja typen suhde sekä alkuaineet. Maa-artisokan mukuloiden ja versojen kuiva-ainesatojen perusteella voitiin päätellä niiden soveltuvan bioenergian tuotannon mädätteeksi. Lisää tutkimusta tarvitaan suositeltavien alkuainepitoisuuksien määrittämiseksi bioenergian tuotannossa käytettävän maa-artisokan mukulalle ja versolle. Typpilannoitetun puhdaskasvuston ja seoskasvustojen välillä ei havaittu merkitsevää eroa kuiva-ainesadoissa. Seoskasvustot pystyvät tuottamaan yhtä paljon satoa kuin typpilannoitettu puhdaskasvusto. Maa-artisokan jääntimukulat muodostivat uuden kasvuston.
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(2018)Buckwheat yield vary greatly between years, and in some years the seed production fails completely. In general, low yield is a problem in buckwheat farming. Only 10-15 % of buckwheat flowers will develop into seeds, regardless of pollination. The reason for this is thought to be the sterilization of the pistils in the flowers, which could be caused by insufficient growth resources during flowering and seed maturing. In addition, the degree of seed filling in the nutlets can be so low that only half of the gross weight of nutlet yield is suitable for nutrition. Buckwheat has been found to be particularly susceptible to insufficient levels of magnesium during flowering, and it also contain more phosphorus than magnesium. However, buckwheat is considered an unambitious plant in terms of fertilization, and its need for micronutrient fertilization has not been studied intensively. However, magnesium fertilization has been shown to increase yield in some experiments. This study was conducted as a foliar fertilization trial in Tuusula. The goal was to determine the effects of magnesium foliar fertilization on the flowering and yield in buckwheat. The treatments included control, water spraying and two magnesium fertilizations treatments. Magnesium fertilization treatment was applied either at the first stages of flowering orat the first stages of flowering and also during full flowering. Magnesium was applied 1,2 kg per hectare. The effects of magnesium fertilization were not statistically significant to the development rate, height of stem, length of flowering, flower biomass, final nutlet yield, 1000 seed weight, number of hollow nutlets, the percentage of nutlet hull or hectolitre weight. There were indications that magnesium has potential to increase nutlet yield. Flowering lasted 12 weeks, which is a normal length for buckwheat in Finland. Nutlet yield was 878-1236 kg per hectare, which is an average yield for buckwheat in Finland. The nutlets had light weight. The amount of magnesium fertilization may have been too low to have an effect on the development and yield of the trial. The trial field suffered from excess moisture in particular during ripening, which has been found to have an adverse effect on the growth and yield of buckwheat. The study was conducted during one growth season and it is presumable that the heavy rains during the season and the excessive moisture in the trial field had an effect on the results of the study. A second year of field experiments in required to verify the effects of magnesium fertilization on the yield formation of buckwheat.
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(2015)Jotta maapallon lämpötilan nousu pysyisi tavoitearviossa, maatalouden kasvihuonekaasupäästöjen alentamistarve on vuoteen 2050 mennessä 42–49% vuoden 1990 päästöistä. Karjatalouden osuus päästöistä on huomattava. Ihmisen toiminta on voimistanut esimerkiksi maaperän luontaisia päästöjä entisestään. Päästötavoitteeseen pääsemiseksi tarvitaan antropogeenisten päästölähteiden kartoittamista, mikä on entistä laajemmin alkanut koskea myös maatalouden toimintoja. Apuna päästöjen kartoittamisessa toimivat esimerkiksi erilaiset elinkaarianalyysiin pohjautuvat kasvihuonekaasulaskurit, jollaisen tuloksiin muun muassa tämän tutkimuksen tulokset perustuvat. Tutkimuksen tavoitteena oli tarkastella lypsykarjatilojen kasvihuonekaasupäästöjä, päästölähteitä ja mahdollisia eroja maiden välillä. Päästöt laskettiin tuotettua maitotonnia kohden. Aineisto muodostui 32 maitotilasta Suomesta, Ranskasta, Alankomaista ja Iso-Britanniasta. Selvisi, että otoksen suomalaisilla ja ranskalaisilla lypsykarjatiloilla kokonaispäästöt olivat liki kaksinkertaiset Alankomaiden ja Iso-Britannian tiloihin nähden. Kaikissa tapauksissa suurin päästölähde oli nautojen pötsikäyminen, mutta suomalaisilla tiloilla pötsikäymisen rinnalla toinen merkittävä lähde oli suorat typpioksiduulipäästöt maaperästä. Suomalaisten tilojen suorat N2O - päästöjen keskiarvot olivat moninkertaiset muihin maihin verrattuna. Maaperätekijät eivät selittäneet N2O päästöjen suuruutta, vaan päästöt korreloivat käytettyjen lannoitemäärien kanssa. Suomessa lannoitteita käytettiin eniten t EKM kohden. Karkearehun osuudella ei havaittu olevan vaikutusta päästöjä vähentävästi tai suurentavasti. Mitä suurempi oli keskituotos, sitä pienemmät olivat pötsikäymisen päästöt maitotonnia kohden. Ranskalaisten tilojen vain noin 5600 kg:n keskituotos heikensi niiden tuotannon päästötehokkuutta merkittävästi. Muissa valtioissa keskituotokset olivat 8000–9000 kg EKM. Voitiin todeta, että suomalaisten tilojen päästöt olivat muihin maihin verrattuna suuremmat. Keski-eurooppalaisten tilojen päästötekijöiden ja päästömäärien välillä havaittiin eroja jotka johtuivat mahdollisesti maatalouskulttuurisista seikoista. Maiden maidontuotannon päästöprofiilia yleistäviin arvioihin tarvitaan lisätutkimusta. Tilatasolla hiililaskuri täyttää sille määritellyt tavoitteet apuvälineenä.
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(2014)The strawberry is the most widely cultivated berry in Finland. Producers in Finland grow short-day varieties of strawberry with the mid-season variety Polka being the most popular. Very little breeding is done in Finland and the characteristics of foreign varieties are not tailored to the local growing con-ditions here. Given these circumstances, it is a challenge to choose varieties for production that will flourish in Finland. The calculated and polyvalent use of different strawberry varieties could prolong the growing season and help stimulate productivity and growth in this area of horticulture. The aim of this research is to develop a rapid test for identifying strawberry varieties whose flowering phenology will suit production in Finland. In this research we aimed to develop a test based on short-day treatment to compare the earliness of different varieties. The influence of short-day treatment on flowering and growth was studied in seven short-day strawberry varieties in a greenhouse experiment. Beside the influence of the treatment on the timing of flowering we tested the relationship between earliness and changes in the vegetative growth of our varieties. The experimental conditions comprised two day-length treatments and one control. The first short-day-treatment lasted six weeks with a photoperiod of 12 h. The second short-day treatment, a so called “step” treatment, lasted nine weeks. The day-length in the step treatment was shortened every three weeks, starting at 16 h, and then dropping to 14 h and 12 h. In the long-day control the day-length was 18 h. The greenhouse temperature was a constant 18 ºC in all treatments. We tested early varieties Honeoye, Elianny, Flair and Wendy, the mid-season variety Polka and late varieties Bounty and Florence. The plants in our experiment didn’t develop as we expected. The early variety Wendy was amongst the first to flower, and the late variety Florence amongst the last in both treatments. The earliness of the other varieties we tested was not consistent with how these varieties flower in the open field. Furthermore, the relative vegetative growth couldn’t be associated with the flowering time. In both short-day treatments the growth of the runners stopped first in the early varieties Wendy, Honeoye and Flair. In the remaining varieties, the growth of the runners was unrelated to the expected earliness of the flowering. The length of the petiole was responsive to the first short-day treatment, but growth of the runners and the petioles did not correlate with early flowering. However slow growth of the late variety, Florence, suggests that the growth rate may be connected with the flower phenology in the variety. Finally, Polka was the variety to exhibit most crown branching in this experiment. According to the results of this experiment the earliness of short-day strawberry varieties cannot be determined with just an experimental short-day treatment. The other growing conditions in the green-house are also likely to affect the response of the tested varieties, potentially masking or interacting with the day-length effect. In addition to day-length, the response of the varieties to the temperature, and to the combined effect of day-length and temperature, should be taken into account. A suitable greenhouse test could comprise day-length and temperature treatments or the combination of both of them. Alternatively flower induction could be performed in the field and subsequently plants could be forced in the greenhouse.
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(2014)The diversity of nature has declined significantly over the past decades. The agricultural diversity has the same trend and the agricultural environments includes of high-value habitats and their associated biodiversity. In the EU and in the Finnish environmental schemes, therefore, efforts have been made to protect and increase biodiversity. Since 2009, voluntary nature management fields have been part of the Finnish’s agri-environmental measures in the agri-environment scheme. These nature management fields include perennial grass fields, game fields, landscape fields and meadow fields. Nature management fields are used specifically to maintain the diversity of the agricultural environment. This study examined two types of nature management fields in summer of 2013. The variety of vascular plants, butterflies and bumblebees was observed in Uusimaa, Finland. The study consists of 40 field blocks, divided into perennial grassland fields (3-4 years) and meadow fields (over 8 years). Nature management field types differed from each other by vegetation, establishment and temporal change. The aim of this study was to provide information which can help in the design and management of nature management fields. The intention is to provide insight on what kind of vegetation could be used to encourage increase in the number and diversity of pollinators, as well as, what kind of the nature management fields promote environmental diversity in farmland. This study was conducted as part of Marjaana Toivonen's dissertation project, “Enhancing biodiversity and ecosystem services through environmental Fallows”. Vegetation was clearly influenced by the time and what was sown in the field. The old perennial grassland fields can preserve and safeguard the permanence of species. Young meadow fields are sown usually with flower seed mixtures. Thus, the abundance of flowering plants is high and the plants provide pollen and nectar for the insects. It was also found that the vegetation was divided according to the type of nature management fields. With pollinators, this trend was not observed as clearly. However, bumblebees were most common in meadow fields. Clear division between the types of fields was not seen in butterflies but they appeared to prefer grassland fields. This study shows that both grassland and meadow fields are needed for protecting biodiversity. Nature management fields have an important role as the multi-species vegetation patches which allow organisms to survive, get food and travel in otherwise monocultural farming environments.
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(2019)Multiplex PCR uses several primer pairs, each specific for different DNA sequences in the same reaction, enabling viruses from different families and genera to be recognized by the same test. The new broad-based method of detecting plant viruses, siRNA analysis, is expected to improve the identification of plant viruses as it does not require a prediction of viruses that may be present in the sample. Due to the method, limiting the test to detecting only certain viruses is unnecessary. The aim of this study was to optimize two or more single-phase multiplex RT-PCR tests for the pest laboratory of the Finnish Food Safety Authority (now known as Finnish Food Authority). The tests were for nine published, degenerate primer pairs for the simultaneous identification of Potyvirus, Potexvirus, Tobravirus and Tospovirus genera, Tobamovirus subgroup 1, Nepovirus subgroups a and b, Bromoviridae family and Carmovirus, Dianthovirus, and Tombusvirus, which belong in the Tombusviridae family. Both multiplex RT-PCR tests and siRNA deep sequencing were used to detect plant viruses from infected samples or samples showing viral symptoms. By identifying the viruses in the plant samples, the goal was to estimate the suitability of multiplex RT-PCR tests for identifying multiple RNA viruses from different genera. siRNA analysis was used to ensure the correctness of the multiplex RT-PCR results. In this study, two multiplex RT-PCR tests were created to detect viruses belonging to eight different virus groups. The obtained results serve as a basis for the validation of the multiplex RT-PCR tests. The validation is required to verify the suitability of the method for its intended use and the reliability of the results of the method. The results showed that siRNA deep sequencing was able to detect almost the whole genome from some of the found viruses. Multiplex RT-PCR tests detected Lupine mosaic virus (LuMV) from lupine (Lupinus polyphyllus Lindl.), Arabic mosaic virus (ArMV) from Chinese astilbe (Astilbe chinensis (Maxim.) Franch.) and from quinoa (Chenopodium quinoa Willd.), Tobacco rattle virus (TRV) from moneywort (Lysimachia nummularia L.) and possibly a new Potyvirus species from honey clover (Melilotus albus Medik.). siRNA analysis detected the same viruses, which increases confidence in the optimized multiplex RT-PCR tests.
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(2018)Many dairy farms harvest three silage crops during summer. Extended growing season and a need to lower the costs of silage are the driving force for three harvests. In Finland the most common forage grass species in silage production are timothy (Phleum pratense L.) and meadow fescue (Festuca pratensis Huds.), cultivated as a mixture. When harvesting three times, the importance of a correct timing of defoliation is essential. The demand of high quality yield makes it even more important. In this master’s thesis, the effects of early and late defoliation rhythm for the growth, devel-opment and quality of timothy, meadow fescue and timothy-meadow fescue mixture were examined. Field trials were conducted in the experiment station of Natural Resources Insti-tute Finland (Luke) in Maaninka during the growing periods of 2015 and 2016. Timothy variety Nuutti and meadow fescue variety Valtteri were used in the experiment. Both vari-eties are suitable for cultivation throughout Finland. Weather conditions varied between the years during the experiment, which affected the dry matter production and the timing of optimal harvest. In year 2016, the beginning of summer had a low rainfall, and the drought affected dry matter yield production. It was notable that in both years the later defoliation rhythm produced greater dry matter yield. Otherwise, tim-ing of harvest had a greater impact for crop and growing parameters than harvesting rhythm. For the first and the second harvest, digestibility determined the right harvesting time. In the third harvest, digestibility was high until the later harvesting times. During the experi-ment, it was also noticed that delaying the harvest did not produce higher dry matter yield. Timothy produced the best dry matter yield, as meadow fescue had better regrowth and dry matter digestibility. Timothy-Meadow fescue mixture’s dry matter yield was as high as timothy’s, however, dry matter digestibility remained higher longer than in timothy.
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(2018)It’s urgent to increase per capita food production to meet the increasing population and its high demand while maintaining environmental stability. Aim to have higher yields as well as reduce harm to the environment, the most difficult problem is how to improve the nutrient use efficiency of plants. Thus using recycling fertilizers is more important in the agriculture practices, it can result in a long-term benefit of plants and environment. In order to explore the impacts of recycling fertilizers on grain yield and on fertilizer nitrogen use efficiency (NUE), an experiment was laid out with the randomized design with 4 replicates of 6 treatments. The objectives were: (1) to test a range of organic fertilizers in arable crop production, especially to find possible differences in nitrogen productivity (2) to find possible differences in nitrogen uptake and in uptake efficiency by rye between variable organic fertilizers and between organic and mineral fertilizers. In the experiment, biogas residual, chemical fertilization, vermicompost, meat and bone meal, sewage sludge compost and unfertilized control were compared. The rates of N application, as kg N/ha varied from one fertilizer to another. This thesis studied impacts on field rye (Secale cereale). There were significant improvements (p < 0.05) in SPAD value, N yield in biomass, total above-ground biomass, and grain yield with the application of the fertilizers, compared with non-fertilized plots. Especially biogas residual, sewage sludge compost and chemical fertilizers were effective. The highest, 33% nitrogen use efficiency was achieved with chemical fertilizer, while sewage sludge compost was the best among organic fertilizers. Recycling fertilizers can produce as high yields of rye as mineral fertilizers, with equal fertilizer nitrogen use efficiency. The critical factor for high yield is the amount of total nitrogen applied, and plant availability of the nitrogen and various organic fertilizers vary in NUE.
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(2018)The aim of this thesis was to study fungicide resistance of Net blotch (Pyrenophora teres f. teres) against SDHI-, QoI and DMI fungicides in cooperation with NORBARAG. This study included both field trials and laboratory testings. The field trial consisted of efficacy assessments and yield level and quality analysis. The main conclusion was that only Proline treatment had a statistically significant lower efficacy against Net blotch and yield levels and quality were lower compared to untreated and other treatments. In a practical point of view, the differences between Proline and other treatments were not significant. Samples that were sent to Denmark for resistance testing had no resistance against QoI fungicides. The aim was also to determine possible resistance against DMI and morfoline fungicides from two Finnish field samples. Leaf samples were collected from Siuntio and Inkoo in 2014. Resistance and efficacy testings against DMI fungicides were done in laboratory. The test was done in laboratory with three different products and three different dose rates. Tested products were Proline (prothioconazole 250 g/l, DMI), Tilt (propiconazole 259 g/l, DMI) and Zenit (propiconazole 125 g/l and fenpropidine 450g/l, DMI and morfoline). Products were compared to untreated treatments. The results was that there were differences between the two isolates, products and dose rates, but no fungicide resistance was detected.
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(2018)Food production in densely populated areas needs to adjust to the pivotal challenges of an increasing population and urbanization. Particularly, this applies for Africa, which will face the highest population growth of all continents within the next 30 years. This is why in the future peri-urban agroforestry is expected to play a more important role in this area of the world. Homegardens which are part of agroforestry systems are seen as one of the ways to improve people’s food security and nutrition security. For households fruit trees offer a variety for the daily diet. Besides the fact that fruits contain various vitamins and other nutrients which help to prevent diseases, selling fruits can additionally offer a source of income for some households. This study found out what kind of fruit tree species people are growing in their homegardens, in the peri-urban area of Dzivarasekwa (Harare), Zimbabwe. The study investigated how households use fruits whether they sell them or use them as a part of daily nutrition. The material was collected by interviewing local people in their homegardens in the fall of 2015. 34 interviews were conducted and 5 descriptive maps of homegardens were drawn. The study found in total 16 different fruit trees, from which the most common were mango, avocado, guava and peach. Also 4 different indigenous fruit tree species were grown in the homegardens. From the interviewed households all of them used fruits as a part of nutrition and eight households also sold fruits to get income. The strongest limiting factor in the cultivation of fruit trees was the small size of the homegardens. However, people would be interested to grow more fruit trees, even indigenous ones, if they had the seedlings available and enough space. People were also interested in better varieties if they would be available. The results show that fruit trees grown in the homegardens can produce fruits for the household for the daily diet all over the year. In addition, fruit sales can bring an extra income for the households.
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(2018)The potato virus Y (PVY) is a type member of the family Potyvirus which infects the nightshade family (Solanaceae) plants. Economically it is considered to be the most siqnificant problem in seed potato production worldwide. Meaningful methods to prevent economical damage caused by PVY are the production of certified seed potato and breeding of PVY-resistant cultivars. The starting point of breeding is identifying different PVY strains. Sequence information from HCPro protein (HCPro) and coat protein (CP) regions are essential to be able to identify different PVY strains and their recombinant forms. The aim of this study was to express the variation in CP and HCPro regions of PVY. This was done by sequencing PVY data from Finlands seed potato fields from year 2015 and comparing it to Yanping Tians (Doctor of Science, Agriculture and Forestry) sequence data from the same area from the years 2006 and 2007. The PVY positive samples used in this study were collected in 2015 in a virus screening test executed by Evira. The screening was done by using ELISA test. The comparison in this study was executed by aligning CP and HCPro regions from all samples and examining the regions by nucleotide and aminoacid level. Comparison was also executed by creating phylogenetic trees from aligned sequences. On the findings of this study the recombinant strain PVY-NTN was the most common strain in Finlands seed potato fields in 2015. Occurence of PVY-O strain was reduced significantly when compared to data from 2006 and 2007. The seven PVY-NTN samples that were examined in this study had a typical aminoacid region to PVY-O strain. This region covers aminoacids R269–K270 and is absent from a known recombinant PVY-NTN ”Nevski” and it is also a singular finding when compared to Yangping Tians samples. However, this change in aminoacid structure did not seem to provoke resistant genes in known potato cultivars to recognize these samples. It is plausible that PVY profits from this new mutation in its aminoacid structure, but this cannot be point out on the bases of this study.
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(2016)The potato virus Y (PVY) is a member of the family Potyvirus, which is the largest plant pathogenic virus family. PVY is one of the most important pathogens of the nightshade family (Solanaceae) plants. PVY is a particular problem in seed potato production, as well as in tomato and pepper production. Some PVY races cause necrotic symptoms (PTNRD) in potato tubers, which will make the tubers unsuitable for use. This thesis studied the ability of several recombinant strains of PVY to infect these three plant species. First objective was to find out which recombinant strains can infect the plants systemically and whether some of them will cause PTNRD symptoms in potato tubers. Secondly, we wanted to find out what parts or even specific amino acids in the HCpro of PVY affect the infection ability of the virus. This was done by comparing the genomes of the recombinant and wild type viruses and based on the experimental data. Finally, we wanted to see if the mutations would persist in the virus genomes for the duration of the infection. The test plants were infected by applying virus contaminated plant juice and grinding powder on the plant leaves. Plants were first grown in growing chambers and then transferred to a greenhouse. The plants were tested for viral infection with DAS-ELISA for three times during different stages of growth. To investigate whether the mutations had persisted in the virus genome, the viral RNA was isolated, multiplied with RT-PCR and then sequenced. Most of the recombinant viruses were not able to systemically infect either of the potato cultivars tested (cv. ‘Nicola’ and cv. ‘Annabelle’). ‘Nicola’ was more susceptible than ‘Annabelle’. The Tyr323Phe-mutation in the HCpro seemed to have a positive effect on the viruses ability to infect ‘Nicola’ in recombinant O5ON-F. PTNRD was caused by recombinants O5NNO45, N605-F and O5ON-F only in ‘Nicola’. Tyr323Phe-mutation had persisted in the N605-F during the infection. Tomato cv. ‘Moneymaker’ was more resistant towards the recombinants than cv. ‘Ildi’, though both cultivars were considerably more susceptible towards the recombinants than either of the potato cultivars or the pepper cultivars. The pepper cultivars tested were resistant towards PVYN605 and PVYOUK.
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(2016)The effects of three rootstocks, B9, MTT1 and MTT5 on yield and fruit quality in ‘Heta’ apple were studied. Observations were done (1) at harvest, (2) four weeks after harvest and (3) six weeks after harvest. Number of fruits per tree was greater on B9 than on MTT5. Fruit ripening was slower on MTT5 than on B9 and MTT1. Streif index and starch content based on iodine test were higher on MTT5 than on other rootstocks. At harvest fruit on MTT5 were firmer than on B9. Firmness decreased on all rootstocks, but after four weeks after harvest it continued to decrease only on MTT5. Fruit dry mass content four weeks after harvest was higher on MTT1 than on MTT5. Dry mass content did not change during storage. Sugar-acid ratio was higher four and six weeks after harvest in fruits on B9 than in fruits on MTT1 and MTT5. Four weeks after harvest fruit on MTT1 had higher TA (titratable acids) content than on B9. Brix was much higher on MTT1 than on MTT5 both at harvest and four weeks after harvest. There was much more boron (B) and iron (Fe) in fruit on MTT5 than on B9 and MTT1. Sulphur (S) content was smaller on MTT1 than on other rootstocks. Zinc (Zn) content was lower on MTT1 from that on other rootstocks. Rootstock had no effect on fruit calsium (Ca), magnesium (Mg), phosphorus (P), copper (Cu), manganese (Mn) and kalium (K) content. Possibly due to young age of the trees (three years after planting) rootstock had no effect on fruit coloring (L, a, b, chroma, hue). In conclusion rootstock B9 stood out positively due to greater number of fruits per tree, early ripening and sweeter fruits, but further research is needed.
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(2016)Plants interact with mutualists and antagonists both below- and aboveground. However, while we know much about the distribution of plants and their aboveground attackers, we lack a thorough understanding of the distribution of the belowground biota. Importantly, recent research shows that the below- and aboveground biota can interact, and there are numerous factors both belowground and aboveground that are involved in these interactions. It is difficult to assess these dynamic interactions that occur within complex communities and which may affect and alter community structure both belowground and aboveground. Here, I set out to investigate these ecological interactions within a plant-mycorrhiza-insect system. I concentrated exclusively on the role of mycorrhizae as the belowground player. I used the larvae of the Glanville fritillary butterfly (Melitaea cinxia) as an aboveground herbivore. I measured the performance of the herbaceous plant (Plantago lanceolata) and the insect larvae to make inference on the plant response and plant-mediated interactions. My results showed that the growth of the experimental plant, P. lanceolata, was, on average, not directly affected by mycorrhizal treatment. Instead, plant-lines responded differently to the impact of mycorrhizal inoculation. This outcome possibly suggests that plant genotypes coming from different populations are interacting differently (in terms of plant growth) to the mycorrhizal treatment. Similarly, aboveground larvae feeding on the same host plant also responded differently to the impact of mycorrhizal inoculation. Larval performance in terms of growth and days to diapause significantly differed between larval families. It may suggest that these features of larval performance might depend more on their family background compared to the type of host plants (with or without mycorrhizae) they are feeding on. Overall, my findings suggest that mycorrhizal fungi affect the performance of the plant and the insects that feed upon the plant, but that genetic variation exists among both plants and larvae in how they are affected by mycorrhizal infection.
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(2020)Tiedekunta – Fakultet – Faculty Maatalous-metsätieteellinen tiedekunta Koulutusohjelma – Utbildingsprogram – Degree Programme Maataloustieteet Tekijä – Författare – Author Heli Birgitta Horppu Työn nimi – Arbetets titel – Title Pölytystehokkuuden parantaminen mehiläisten (Apis mellifera) käyttäytymisen ohjailulla Oppiaine/Opintosuunta – Läroämne/Studieinriktning – Subject/Study track Maatalouseläintiede Työn laji – Arbetets art – Level Pro gradu Aika – Datum – Month and year 10/2020 Sivumäärä – Sidoantal – Number of pages 36 Tiivistelmä – Referat – Abstract Monet viljelykasvimme hyötyvät merkittävästi hyönteispölytyksestä, joka parantaa sadon määrää ja laatua. Hyönteispölytyksen positiivinen vaikutus ilmenee esim. marjakasveilla satomäärien kasvuna, - kauppakuntoisten marjojen osuuden noustessa. Mansikan (Fragaria ananassa) heikko houkuttelevuus mehiläisten (Apis mellifera) pölytyskohteena on herättänyt kysymyksiä, voisiko pölytystehokkuutta tämän kasvin kohdalla lisätä mehiläishoidollisin keinoin. Tässä tutkimuksessa testattiin mahdollisuutta ohjata mehiläiset haluttuun kohteeseen, kukkivalle mansikalle. Tutkimus tehtiin Mönkkösen marjatilalla Leppävirralla. Mehiläispesiä ruokittiin mansikan siitepölyä sisältävällä sokeriliuoksella. Tarkoitus oli ehdollistaa mehiläiset mansikan siitepölyn tuoksuun, ja saada ne valitsemaan mansikka pölytyskohteekseen. Mehiläisten kukkavalintoja tutkittiin keräämällä mehiläispesistä siitepölynäytteitä, ja analysoimalla niistä mansikan siitepölyjen osuutta. Kokeessa sokeriliuosruokinta ei lisännyt lainkaan mansikan siitepölyjen osuutta tutkituista siitepölyotoksista. Syitä siihen voi olla monia. Aineiston niukkuuden takia satunnaisvaikutuksen osuus saattoi vääristää kokeen vaikutusta. Myös ympäristön muu houkutteleva kasvillisuus saattoi siirtää mehiläisten huomion pois mansikalta. Mehiläisiä voimakkaasti houkuttelevan vadelman kukinta osui samaan aikaan mansikan kukinnan kanssa, ja koe-alueiden läheisyydessä oli myös runsaasti muuta kukkivaa luonnonkasvillisuutta. Mehiläisten keräämästä siitepölystä valtaosa oli peräisin ruusukasveista (Rosaceae). Ruusukasvien heimon sisällä eri kasvisukujen osuudet vaihtelivat riippuen pesien sijainnista. Mehiläisten kukkavalintoihin johtavat syyt ovat monimutkaisia, eivätkä helposti ihmisen ohjailtavissa. Vaikka koeaineisto oli liian pieni menetelmän vaikutuksen todistamiseksi, pesistä otettujen siitepölynäytteiden perusteella saatiin kuitenkin arvokasta uutta tietoa mehiläisten kukkavalinnoista ja käyttäytymisestä. Avainsanat – Nyckelord – Keywords Mehiläinen (Apis mellifera), pölytys, pölytyskäyttäytyminen, siitepöly, mansikka (Fragaria ananassa), ruusukasvit (Rosaceae) Ohjaaja tai ohjaajat – Handledare – Supervisor or supervisors Marjaana Toivonen ja Irina Herzon Säilytyspaikka – Förvaringställe – Where deposited HELDA - Helsingin yliopiston digitaalinen arkisto / HELDA - Helsingfors universitets digitala publikationsarkiv /HELDA - Digital Repository of the University of Helsinki Tiedekunta – Fakultet – Faculty Faculty of Agriculture and Forestry Koulutusohjelma – Utbildningsprogram – Degree Programme Agricultural Sciences Tekijä – Författare – Author Heli Birgitta Horppu Työn nimi – Arbetets titel – Title The efficiency of pollination, How to improve it by managing honeybee behaviour? Oppiaine/Opintosuunta – Läroämne/Studieinriktning – Subject/Study track Agricultural entomology Työn laji – Arbetets art – Level MSc thesis Aika – Datum – Month and year October 2020 Sivumäärä – Sidoantal – Number of pages 36 Tiivistelmä – Referat – Abstract Insect pollination is beneficial to many crop plants, increasing the yield and quality of the crop. E.g. with berries the insect pollination contributes to increasing crop yields when the proportion of marketable berries is growing. The weak attractiveness of strawberry (Fracaria ananassa) as a pollination object for honeybees (Apis mellifera) has raised question, whether honeybee management could increase the pollination effectiveness for strawberry. This study was testing the possibility of guiding honeybees to the object desired i.e. the blooming strawberry. The study was carried out at Mönkkönen berry farm in Leppävirta. The honeybees were fed with sugar solution containing strawberry pollen. The aim of the study was to condition the honeybees to the scent of strawberry pollen, thus making them choose strawberry as their pollination object. The flower preference of honeybees was studied by collecting pollen samples from the honeybee nests and analyzing the content of strawberry pollen in the samples. The study shows, that the increase of strawberry pollen in the analyzed pollen samples was not statistically significant. Reasons for this are various. The random effect due to the scarcity of samples may have affected the results. Also the overwhelming attraction of surrounding vegetation may have pulled away the honeybees focus from the strawberries. Raspberry (Rubus idaeus), which is a strong attraction to honeybees, was vigorously blooming at the same time and close by to the study area there were numerous strongly blooming other natural plants. Most of the pollen collected by honeybees were from family Rosaceae. Within the rose family the pollen collected from different genie varied according to the location of nests. The reasons for honeybees to choose a specific flower are complex and not easily controlled by human. Even though the samples were too scares to prove that conditioning of honeybees to strawberry pollen is effective, we have valuable new knowledge of honeybee flower preferences and behavior. Avainsanat – Nyckelord – Keywords Honeybees, pollination behaviour, pollination, pollen, strawberry, Rosaceae-family Ohjaaja tai ohjaajat – Handledare – Supervisor or supervisors Marjaana Toivonen ja Irina Herzon Säilytyspaikka – Förvaringsställe – Where deposited HELDA - Helsingin yliopiston digitaalinen arkisto / HELDA - Helsingfors universitets digitala publikationsarkiv /HELDA - Digital Repository of the University of Helsinki
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(2018)Avoimet puutarhat on Puutarhaliitto ry:n hallinnoima valtakunnallinen puutarhatapahtuma, jolloin puutarhojen portit aukeavat vierailijoille yhden päivän ajaksi. Tapahtuma on järjestetty vuodesta 2012 lähtien ja siitä on tullut suosittu puutarhaharrastajien keskuudessa. Tapahtuma on avoin kaikille ja kuka tahansa voi ilmoittautua mukaan teemapäivään puutarhansa kanssa. Teemapäivään osallistuu vuosittain lähes 500 puutarhaa ympäri Suomen ja päivän aikana tehdään kymmeniä tuhansia puutarhavierailuja. Tutkimusaineisto kerättiin vuoden 2016 teemapäivään osallistujille suunnatulla kyselyllä. Kysely lähetettiin sekä sähköisenä että paperisena lomakkeena ja siihen oli mahdollista vastata 9.8.–9.9.2016 välisenä aikana. Kyselylomakkeen avulla pyrittiin selvittämään puutarhaharrastajien motiiveja ja odotuksia teemapäivään osallistumisesta sekä sitä, mitä puutarhaharrastus heille merkitsee. Vastauksia kyselyyn saatiin yhteensä 195 kappaletta. Vastauksia analysoitiin kvantitatiivisin ja kvalitatiivisin menetelmin. Moni kyselyyn vastannut luokitteli itsensä pitkäaikaiseksi harrastajaksi ja oli osallistunut tapahtumaan useammin kuin kerran. Puutarhanhoito oli vastaajille mieluisa harrastus ja moni heistä koki puutarhan antavan hyvää oloa ja parantavan hyvinvointia. Vastaajia kiinnostivat enemmän puutarhan esteettisyys ja kukinta kuin hyötykasvienviljely. Avoimet puutarhat on osallistujille tärkeä tapahtuma, joka mahdollistaa puutarhan esittelemisen puutarhaharrastajan näkökulmasta. Teemapäivän merkitys puutarhaharrastajien omana tapahtumana korostui kyselyn vastauksissa. Tärkeinä asioina koettiin muun muassa vuorovaikutus puutarhavierailijoiden kanssa, mahdollisuus tutustua muihin samanhenkisiin ihmisiin, hyvän mielen tuottaminen muille, oman osaamisen ja tekemisen esitteleminen puutarhassa sekä tiedon välittäminen.
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(2014)Flavonoids are a group of secondary metabolites, which are not only important for plants’ survival, but also have been found to have medicinal properties for human health. Several enzymes are involved in the flavonoid biosynthesis. It is thought that these enzymes work together and may form enzymatic complexes. But the way of these enzymes interact with each other is still not clear. In arabidopsis, the number of gene family members that encode these enzymes is less than in other model plants, which makes it as a suitable model to investigate the interactions of enzymes involved in the flavonoid biosynthetic pathway. In this study, ten full-length flavonoid pathway genes were successfully amplified from cDNA of the arabidopsis flower. They are PAL1, C4H, CHS, CHI, F3H, F3’H, DFR, FLS1, ANS and GT. These genes were cloned into different prey vectors (pPR3-N and pPR3-SUC) and bait vectors (pDHB1 and pBT3-SUC). After that, the constructs were transformed separately into yeast. The protein-protein interactions were analyzed via yeast two-hybrid system.
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(2016)Fusarium species lower the germination of oat (Avena sativa) seeds and cause losses in yields. Fungicidal seed treatments prevent fungal diseases from spreading through seeds and soil. This study was conducted to determine how different fungicidal seed treatments affect the germination of oat seeds and the Fusarium species present in laboratory conditions applying official ISTA germination test methods on filter paper and sand. Aim was also to detect the damages fungi cause to oat seedlings as well as the effectiveness of different seed treatments and the resistance of oat cultivars to Fusarium. The germination percentages and damages were detected in two studies. In the first study, oat seeds were germinated on both filter paper and sand and treated with fungicidal seed treatments (Baytan Universal, Celest Trio and Zardex G). In the second study, oat seeds were inoculated with Fusarium culmorum and germinated on filter paper. Additionally, the effect of mould fungi on germination in several different geographical areas, years and cultivars was investigated based on the official germination tests conducted by Evira, who used samples analysed for certifying. Differences were detected between cultivars in their germination and damages caused by fungi in different geographical areas and years. In general, there were more damages in the seed lots with lower germination. The fungicidal seed treatments decreased damages clearly but increased germination only slightly. Only slight differences were observed between the researched seed treatments in their abilities to increase the germination of oat but there were greater differences in their abilities to decrease the amount of Fusarium and the damages they caused to oat seeds. The seed treatment with fludioxonil, difenoconazole and tebuconazole as active ingredients was the most effective against the damages caused by Fusarium in laboratory conditions. Additionally, the germination of oat was better with the sand germination method than on filter paper. However, there were more damages on oat seedlings germinated on sand than on filter paper.
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(2020)Green roofs and facades may provide multiple benefits for urban areas, such as retain storm water run-off, reducing heat-island effect, supporting biodiversity and providing places for food production and community gardening. However, without successful vege-tation it is hard to achieve the benefits that green roofs and facades may provide. Green roofs and facades are not favourable sites for vegetation so plants must be able to thrive in harsh conditions. It is important to test the suitability of plants in that kind of environmental conditions and climate prevailing at the planting site. In this study, we observed the growth and hardiness of woody plants on green roofs and facades of an apartment block of flats in southern Finland. The effects of environmen-tal factors on plant success were examined on three facades facing different directions. The observations covered the first year after planting. The number of woody species stud-ied was 32, including trees, shrubs and vines. For some species, several varieties were test-ed, so the total number of plant taxa was 52. The observation period lasted from December 2017 to September 2018. The growth and visual appearance of the plants were measured using several variables. Based on the first growing season, most of the taxa studied displayed a good survival potential in prevailing growing conditions. There were only slight differences between survival of taxa. Especially direction of the façade had impact on plant survival. Plants on green walls showed the highest mortality on the west facade, but the later planting date may have influenced the results on that facade. The results can be confirmed only after a longer follow-up period.
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