Browsing by discipline "Kasvintuotannon biologia"
Now showing items 41-44 of 44
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(2015)The great web-spinning pine-sawfly is a common species in Finland. Few mass outbreaks have occurred in Europe, but they have last a long time. Yet first outbreak in Finland was observed at Yyteri region near Pori in 2006. Larvae use pine needles as nutrient. It is estimated that 100–200 larvae/m2 is a level for severe forest damage. There have been many locations containing 200–500 larvae/m2 at the Yyteri region. There is tourism and nature value in Yyteri and so chemical control was not the first option. That is why biological control was used and the most promising seem to be Steinernema feltiae. It was commercially available and spraying it was simple. The purpose of the research was to find out how S. feltiae could be used to reduce the great web-spinning pine-sawfly on a large scale. Spraying was done by using agricultural spraying equipment attached to tractors. Photoelecton traps were used and soil samples of larvae were collected. Control traps gathered 65.0 % of adults in 2011 while treatment traps gathered 35.0 %. In 2012 traps collected 48.6 % and 51.4 %, respectively. Traps gathered 120 adults in 2011. Main swarming was 2012 and 469 adults were caught. Some unreliability is involved in results because of the high spatial distribution of larvae in soil. Differences between years might be explained by earlier metamorphosis of the great web-spinning pine-sawfly to adult, increased deviation of trap results and grassier field conditions. Chilly weather might also have prevented nematodes performing at maximum capacity in 2012. In soil samples 88.6 % of the great web-spinning pine-sawflies were alive. It seems that most of them would be overwinter for fourth year. Most of the dead great web-spinning pine-sawflies (90.3 %) were found in organic soil layers. However, the clear-cut area has stayed at 200 ha for now.
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(2016)Ubiquitin is an important modifier in eukaryotic cells through many effects on the targeted protein. Ubiquitination is a reaction cascade, catalyzed by E1 – E2 and finally E3 enzyme which completes the ubiquitination. In this study preselected 61 RING type ubiquitin E3 proteins of Arabidopsis thaliana were classified, grouped and analysed to characterize what kind of domains and groups were included. Proteins which contain a RING domain, can either ubiquitinate substrates independently or function as part of a multi-subunit complex. RING E3s are known to act as a molecular adaptors for the E2s and the substrates. It is the E3 ligase that is responsible for selecting the target protein for ubiquitination and later for degradation in proteasome in to peptides. The same preselected 61 genes were also researched from the Betula pendula Roth genome. Web Apollo database was used to annotate genes from the recently sequenced silver birch genome. As a result 32 gene homologs that included RING domain were identified in silver birch.
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(2016)Viikin arboretum on tärkeä luonto- ja virkistyskohde monille helsinkiläisille. Arboretumin hoito- ja kehittämissuunnitelmaa laadittaessa vuonna 2014 tuli esiin tarve selvittää arboretumin eri käyttäjäryhmiä. Tämän tutkimuksen tavoitteena oli kartoittaa Viikin arboretumin kävijärakennetta ja mitä arboretumissa harrastetaan sekä käyntimotiiveja ja millaisia motiiveihin perustuvia kävijäsegmenttejä arboretumissa on. Tutkimuksessa selvitettiin myös eri segmenttien tyytyväisyyttä Viikin arboretumin palveluihin, rakenteisiin ja ympäristöön. Tutkimusaineisto kerättiin kyselytutkimuksella, joka toteutettiin jakamalla paperisia kyselylomakkeita Viikin arboretumissa 4.–30.7.2014 välisenä aikana sekä sähköisellä lomakkeella 20.8.–16.9.2014. Vastauksia saatiin yhteensä 260 kappaletta. Kävijäsegmenttien muodostamiseen käytettiin pääkomponenttianalyysia ja k-keskiarvon ryhmittelyanalyysia. Kävijät ottivat osaa monenlaisiin aktiviteetteihin käydessään Viikin arboretumissa.Tavallisimpia arboretumin käyttömuotoja olivat pyöräily ja kävely sekä kaikenlainen luonnon tarkkailu. Maisemat, luontoelämykset ja hyvät ulkoilureitit olivat tärkeimmät syyt käydä arboretumissa. Viikin arboretumin pääasiallisia käyttäjäryhmiä olivat ulkoilu- ja virkistyskäyttäjät, opetus- ja tutkimuskäytön merkitys oli vähäinen. Kävijät olivat yleisesti ottaen tyytyväisiä Viikin arboretumiin. Aineistosta tunnistettiin yhteensä kolme motiivipohjaista toisistaan eroavaa kävijäsegmenttiä: luontokeskeinen ulkoilija (38,8 % kävijöistä), liikunnan harrastaja (44,7 %) ja kasviharrastaja (16,5 %). Luontokeskeiset ulkoilijat ja liikunnan harrastajat käyttivät arboretumia jokapäiväiseen virkistäytymiseen. Kasviharrastajat tulivat tutustumaan arboretumin ainutlaatuiseen kasvillisuuteen kauempaakin. Kävijäsegmenttien tunteminen auttaa alueen suunnittelijoita ja hoitajia kehittämään Viikin arboretumia ja kohdentamaan palveluita ja viestintää tehokkaammin.
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(2015)Crop rotation is an important farming practice in organic agriculture. In the research it has been shown that diverse crop rotations enhance productivity as well as agrobiodiversity, and thus the organic regulations of EU obliges the farmers to have diverse rotations on their farms. However, it is unclear what kinds of crop rotations have been implemented on Finnish farms. In this master’s thesis the aim was to find out what kinds of crop rotations plans there were used on 21 organic arable farms on Uusimaa and Satakunta regions in the Southern Finland and how the plans were put into practice during 2008–2012. The aim was also to study, if there were differences between the regions. The study material consisted of the crop rotation plans which are required from the farmers in the beginning of 5-year organic subsidy period and of the information from EU’s IACS-database about the crops grown on farms. The typical crop rotation on the organic farms was the alternation between cereals and ley, in different pace on different field plots. Also the winter rye – oat – two- or three-year ley was a typical crop rotation. Crop rotation plans and realized crop rotations were compared with each other by “realization index”, which was developed by this study. The realization index showed that the plans were followed every year less and less on the average, but on the same time it was also typical to come back to the plans. However, as a consequence of the changes made into the plans, the field area of the farm was usually not an entity, bound together by crop rotation, but the crop rotation was planned for the each field plot separately. There were statistically significant differences in crop rotations plans between regions. In Uusimaa region the crop rotations were based on crop types whereas in Satakunta region the crops to be grown were identified more precisely. Several future research topics emerged, such as the significance of crop rotations in organic agriculture, farmer’s strategies in crop rotation design and the sustainability as well as productivity of those strategies.
Now showing items 41-44 of 44