Browsing by discipline "Plant Production Biology"

Kurtturuusun perusmuoto (Rosa rugosa L.) on ollut vuosikymmenten ajan suosittu koristekasvi pitkän kukintakautensa, kestävyytensä ja helppohoitoisuutensa takia. Kuitenkin nykyisin kurtturuusu luokitellaan Suomessa erittäin haitalliseksi vieraslajiksi. Kurtturuusua pidetään haitallisena vieraslajina myös Luoteis- ja Keski-Euroopassa sekä Pohjois-Amerikassa. Risteymätaustansa takia kurtturuusulajikkeiden ja –risteymien lisääntymiskyvyn on oletettu olevan heikompi kuin kurtturuusulla. Tämän tutkimuksen tavoitteena oli tutkia kurtturuusun puutarhamuotojen lisääntymiskykyä ja arvioida niiden leviämisalttiutta luontoon. Tutkimuksen päätavoitteena oli selvittää, mitä lajikkeita tai risteymiä voitaisiin suositella käytettäväksi kurtturuusun sijaan. Leviämisalttiutta arvioitiin vesomisen, kukinnan ja kiulukoiden tuoton runsauden, kiulukkakohtaisen siemenmäärän, siementen elinkyvyn ja siementen itävyyden avulla. Aineistoa kerättiin sekä Etelä- että Pohjois-Suomesta ja mukana oli kurtturuusun perusmuodon lisäksi 12 ruusulajiketta tai –risteymää, joiden vanhempiin kurtturuusu kuuluu. Tutkimuksessa näiden puutarhamuotojen lisääntymiskykyä verrattiin kurtturuusun perusmuodon lisääntymiskykyyn. Kukinta- ja vesomishavainnot tehtiin kesällä 2011 ja kiulukat kerättiin syyskuussa 2011. Siementen elinkyky testattiin tetrazoliumtestin avulla ja kaksivuotinen idätyskoe Helsingin yliopiston Viikin kampuksella kesti syyskuusta 2011 lokakuuhun 2013. Tutkimuksen mukaan puutarhamuotojen lisääntymiskyvyssä on paljon vaihtelua niin taksonien kuin kasvupaikkojen välillä. Osalla puutarhamuodoista oli yhtä hyvä lisääntymiskyky kuin perusmuodolla. Kurtturuusun puutarhamuodot tuottivat kiulukkakohtaisesti vähemmän siemeniä kuin perusmuoto. Niiden siemenet olivat yhtä elinkykyisiä kuin kurtturuusun perusmuodon, mutta keskimääräinen itävyys oli heikompi kuin kurtturuusun perusmuodon siementen. Puutarhamuotojen välillä oli eroja niin siemenmäärissä kuin siementen elävyydessä ja itävyydessä. Tämän tutkimuksen perusteella ei suositella käytettäväksi sellaisia puutarhamuotoja, jotka tekevät paljon siemeniä tai joiden siemenet hyvän elinkyvyn lisäksi itävät keskivertaisesti. Pitkäkestoiselle jatkotutkimukselle on tarvetta, jotta lisääntymiskykyyn liittyvien ominaisuuksien vuotuisesta vaihtelusta voitaisiin varmistua.

The aim of this thesis was to study differences between the yields and stability of grass mixtures and pure stands. In addition, the quality of forage was examined. Timothy cultivars which had different growth rhythms were selected for field experiments. The aim was also to examine how species proportions differ in mixtures between years and harvests and what causes observed variation. Moreover, the effect of the effective temperature sum on the quantity and quality of yield was evaluated. A three year field study was carried out in Jokioisinen and Sotkamo. Plots had either pure timothy stands (Phleum pratense L. cultivars Tuure, Rhonia ja Bor 0301) or mixtures that contained 75% timothy and 25% meadow fescue (Festuca pratensis Huds. cultivars Ilmari ja Klaara). Dry yield (kg ka/ha), D-value, iNDF, NDF, protein and lignin content were determined from each harvest. In addition, botanical composition was analysed in Sotkamo. Grass mixtures had higher dry yields and they were more stable than pure stands. The difference in yileds was more significant in Sotkamo than in Jokioinen. Timothy-meadow fescue growths' NDF and iNDF were closer to desired values than pure stands', but with other quality features weren't discovered advantages. In Sotkamo timothy cultivar's and type's (southern or north) dry yield, D-value, NDF, protein content and botanical composition reacted differently with the effective temperature sum. In Jokioinen the yield and quality of varieties reacted similarly with the effectice temperature sum. All timothy cultivars benefited occasionally from adding a meadow fescue to the mixture but not consistently. Year and harvest affected to the species proportions in the mixtures. Also the effective temperature sum had a correlation with yield and quality. According to the results cultivating grass mixtures instead of pure stands is a good way to achieve bigger dry yields that have high quality.

Meat and bone meal is a by-product of rendering industry. It contains significant amounts of nutrients, for example 2720 tonnes per year phosphorus in Finland. The use of meat and bone meal in agriculture ceased because of the mad cow disease in 1994. Meat and bone meal has been proved to nearly equal mineral fertilizers both economically and in fertilization effect with many crops. The use of high phosphorus content meat and bone meal as fertilizer decreases the need for non-renewable phosphorus resources and closes food system nutrient cycles. The objectives of this thesis were to consider the suitability of meat and bone meal in potato production and to estimate the recycling potential of meat and bone meal in potato production in Finland. The recycling potential was calculated as a ratio between the annual phosphorus demand in potato production and the amount of phosphorus in meat and bone meal produced in Finland. The mean yields of potato as well as the fertilization rates in agri-environment measures and the plant-available proportion of meat and bone meal were used in calculation. The annual phosphorus demand of potato production was estimated as 1100 tonnes and the amount of plant-available phosphorus in meat and bone meal was estimated as 1630 tonnes. This number includes a category 1 disease risk material which must currently be disposed of. The recycling potentials of meat and bone meal were calculated as 67 % and 74 % for all the material and excluding the category 1 material, respectively. Consequently, the amount of phosphorus in meat and bone meal can supply the demand in potato production. Meat and bone meal is a long-term phosphorus fertilizer and suitable for potato production in Finnish conditions if nitrogen and potassium are supplemented to meet the crop’s demand with other fertilizer products. It’s also an advantage that meat and bone meal is accepted in organic production. In a recycling nutrients point of view, the utilization of meat and bone meal as a fertilizer for instance in potato production is a good opportunity to return nutrients to the agroecosystem’s cycle.

Street trees are an important part of a comfortable urban environment. Their beneficial effects in the built environment have been documented in a number of ways around the world. In urban environment tree roots are often grown in limited volumes of soil and competing for space with artificial construction materials and technical structures. Low oxygen concentrations in urban soils are considered as one of the major growth limiting factors, particularly under street pavements. The terrestrial growth conditions are difficult to alter in urban environment. By improving below-ground conditions, tree well-being and sustainability can be significantly increased. Increased ensign of growing conditions and the awareness of the value of urban trees have contributed to the creation of landscaping applications such as structural soil. This study compared gas concentrations in the air of structural and conventional soils, used in roadside tree plantings in the City of Helsinki. Soil air samples were collected during growing seasons 2012 and 2013. Proportions of nitrogen, oxygen, carbon dioxide and methane in soil air were determined by a gas chromatograph. CO?-fluxes were used to evaluate the effect of the soil surfacing material to ground ventilation. Structural soil contained more oxygen in all depths compared to conventional tree soil. A strong correlation existed between oxygen and carbon dioxide concentrations. It seems that cobblestone coating with wide seams does not impair the ground ventilation compared to soil covered with cast-iron grate. Atmospheric growth conditions were more favorable in the structural soil; however the oxygen concentrations in conventional soil were also high.

Suomenlinna is a sea fortress that consists of eight islands and it is a very popular tourist attraction in Helsinki. The vegetation of Suomenlinna has been influenced by its location in the outer archipelago and by the previous military use. The primary aim of this study was to explore the composition and abundance of plant species in soil seed banks of dry meadows at Kustaanmiekka. The established vegetation of the dry meadows was studied in 2009. Soil seed samples were collected in April 2011 from ten dry meadows located around Kustaanmiekka. The samples were taken from two different soil layers: 0-4,5 cm and 4,5-9 cm. Seedling emergence method was chosen to study the seed banks. It was carried out from May to October 2011 in the Viikki campus greenhouse at the University of Helsinki. A total of 5887 seeds from 83 taxa germinated from the soil seed bank samples. The most common species were Berteroa incana (L.) DC., Festuca rubra L. and Potentilla argentea var. argentea. The seed banks contained a few polemochorous species (Berteroa incana, Epilobium hirsutum L. and Silene latifolia Poir. ssp. alba (Mill.) Greuter & Burdet which were brought in Finland with military troops. Noteworthy species found only in the seed bank were Descurainia sophia (L.) Webb ex Prantl and Matricaria recutita L.. The seed density varied from 5030 to17600 seeds/m2. Compared to the short-lived species, the amount of perennial species and their seeds was greater in the seed banks. The number of species and seeds differed between the dry meadows. A 2 luonnonalue had the highest number of species while Makeavesialtaiden luonnonalue and Kustaanmiekan sisäosan hiekkataso had the highest number of seeds. The total number of species and the average number of seeds didn´t correlate with the content of the main nutrients or humus in the soil, nor with soil pH or soil type. The soil seed banks could be utilized in the maintenance of the dry meadows in Kustaanmiekka by uncovering and breaking the soil. Rare meadow species that reproduce from seeds and that are still present in the vegetation would also benefit from this. More research is needed to determine the best method to utilize the soil seed banks when seeking to recruit as many species from the seed bank as possible.

Gray mold (Botrytis cinerea) is an important disease of strawberry. The pathogen is spread by spores to strawberry flowers, from where the disease spreads to the developing berries. It progresses fast especially in high humidity and without any control. It can destroy even half of the crop. In conventional production, the strawberries have been sprayed by fungicides several times in beginning of summer. Only approved biological fungicides in Finland are Prestop- ja Prestop mix (Verdera Oy), and those can be spread to strawberries by honey bees (Apis mellifera), witch visits in the flowers of strawberry. For this task, the special additional equipment must been installed to hives. Inquiry survey have been made for the strawberry growers, witch have used the entomovectoring control method. The survey clarifies the problems of beginning to use the method, laboured and profitability, problems relating to bees and the needs of develop. Result of the survey is, that the growers have quite committed to use entomovectoring control method, even that many growers told that it was laboured and the efficency could not been seen clearly. The main reasons for the use of method were control of gray mold, reduce of chemical control and safety for user and environment. In addition to method gave image benefit to grower and improved pollination of strawberry. Getting started and use of method were more often trouble-free. The main development points were to extent the time between the addition of pesticide to the spreader equipment and to develop the method for commercial bumble-bee (Bombus terrestris) hives.

Blackcurrant (Ribes nigrum L.) is a woody plant in cold regions and it adapts well for the Finland’s boreal zone. There were less than 600 companies farming blackcurrant and green currant in 2014 and the acreage was 1449 ha and the level of yield was over 1000 kg/ha. In year 2016, the number of companies were 544 and the acreage was 1435 ha and the level of yield less than 1000 kg/ha. There has been a pressure to reduce the high price of domestic blackcurrant, due to that the inexpensive imported berries have been taken more position in industry. The global warming can be a serious threat for the cultivation of blackcurrant in the future. There is a need for new cultivars of blackcurrant in Finland and the objective of this research was to examine the depth and reversal of on dormancy on various points of time and the resilience of winter. For the results the bud burst was monitored in quantity and temporal on forcing. The processing of release of dormancy in various temperatures and light conditions before the forcing was also included to the research. The cold hardiness was tested in temperatures, which was descending step by step in controlled sub-zero experiment. The results demonstrated that the bud burst was the lowest during the deepest dormancy in OctoberNovember and the largest in February, when the dormancy was already released. ‘Almiai’ and ‘Gagatai’ were the best cultivars, which were able to maintain the dormancy; in first forcing in October, bud burst 0 %. The bud burst was particularly substantial in February and ‘Ben Tron’ the bud burst was even 80 %. In October-November the time elapsed for bud burst was highest and least was in February with average of 10 days. The most optimal temperature in dormancy release was 0 ⁰C. On the cultivar ‘Mikael’ the bud burst was quicken in +18 ⁰C . The longer the processing time was, the shorter was the time for bud burst. The temperatures +12 ⁰C and +18⁰C were too high for dormancy release. In cold hardiness, the cultivars didn’t differ much from each other. The results demonstrate that the cultivars differ from each other in the depth of dormancy and release. ‘Almiai’ and ‘Gagatai’ maintained best their dormancy. These cultivars could be suitable options for farming in Finland. They were also winter hardiness. In the future, there should be breeding of blackcurrant cultivars, which adjust different kind of environments. Additionally, we should discover and breed cultivars, which have good resistant for winter and maintain dormancy, even though the temperatures are varying in winter.

Tutkimuksen tavoitteena on selvittää Festuca rubra subsp. oelandica -alalajin mahdollinenkäyttöarvo geenivarantona jalostettaessa ilmastonmuutokseen sopeutuvia viljelykasveja. Työssä tutkittiin lajin potentiaalia toimia geenivarantona tarkastelemalla kolmen Festuca rubra subsp. oelandica -populaation kloroplastien geneettisiä rakenteita mikrosatelliittien (cpSSR) avulla. Tutkimukseen sisällytettiin 58 alun perin kolmelta kasvupaikalta Öölannista kerättyä yksilöä.Tutkimus toimi lisäselvityksenä Luonnonvarakeskuksen ”Manipulating Grass – Fungal Endophyte Symbioses to Reduce Greenhouse Gas Emissions and Increase Soil Carbon Sequestration in Pastures of Finland, New Zealand, and the United States” -hankkeeseen liittyen. Kolmen öölanninpunanatapopulaation kloroplastien geneettisiä rakenteita tarkasteltiin alleelien muuntelua kuvaavien muuttujien, pääkoordinaattianalyysin, Bayesialaisen populaatiorakenneanalyysin sekä molekylaarisen varianssianalyysin perusteella. Pääkoordinaattianalyysin mukaan öölanninpunanatan kloroplastien geneettiset rakenteet eroavat merkittävästi muista pohjoiseurooppalaisista F. rubra-populaatioista. Analyysin mukaan öölanninpunantan kloroplastit olisivat jakautuneet viiteen geneettiseen ryhmään. Populaatioiden kloroplastien alleelien muuntelua kuvaavien muuttujien perusteella ei havaittu populaatioiden välisiä tilastollisesti merkitseviä eroja. Varianssianalyysin mukaan aineistossa havaittu muuntelu oli lähes yksinomaan yksilöiden välistä muuntelua. Populaatioden välillä ei havaittu varinassianalyysin perusteella tilastollisesti merkitseviä eroja. Populaatiorakenneanalyysin mukaan aineiston optimaalisin jaottelu saavutettiin jakamalla aineisto viiteen klusteriin. Klusterijako ei noudattanut oletettujen maantieteellisten populaatioiden jakoa. Klustereille suoritetun varianssianalyysin mukaan aineistossa havaittu muuntelu oli lähes yksinomaan yksilöiden välistä muuntelua. Klustereiden välillä ei havaittu varianssianalyysin perusteella tilastollisesti merkitseviä eroja. Käytettyjen menetelmien avulla aineistosta ei havaittu tilastollisia merkitsevää geneettistä ajautumista eikä aineistosta löydetty tilastollisesti merkitseviä osapopulaatioita. Öölanninpunanatan arvioitiin soveltuvan Festuca-sukuisten kasvien sekundääriseksi geenivarannoksi. Öölanninpunanatan mahdollinen polveutuminen eri jääkaudenaikaisesta kannasta kuin nykyiset viljellyt Festuca- ja Lolium-lajikkeet saattaa muodostaa kiinnostavan perinnöllisten ominaisuuksien varannon kasvijalostuksen kannalta. Lisätutkimusta kaivataan, jotta voidaan määrittää tarkemmin öölanninpunanatan sijainti Festuca-suvun taksonomiassa sekä lajin käyttömahdollisuudet viljelykasvien jalostuksessa. Alvarmaiden pirstaloituminen saattaa muodostaa uhan öölanninpunanatan muodostamalle hyödyntämättömälle geneettiselle varannolle.

Bacterial soft rot and blackleg are amongst the major diseases of potato (Solanum tu-berosum L.). In Finland Pectobacterium atrosepticum, Pectobacterium carotovorum subsp. carotovorum, Pectobacterium wasabiae and Dickeya-species cause rotting of the tuber and softening of stems on potato. These diseases cause major postharvest losses and weaken the quality of the crop, which is a problem in seed potato production. The aim of this study was to determine whether the antagonistic bacteria are toxic to in vitro plants, as well as to study the ability of the antagonistic bacteria to spread inside or on the in vitro plants. It was also investigated if the antagonistic bacteria can prevent soft rot of potato in in vitro plants, as well as the ability of the antagonistic bacteria to prevent the spreading of soft rot bacteria from soil to the plants. This study was carried out in laboratory and in greenhouse conditions in the University of Helsinki at the Department of Agricultural Sciences. As potato material cultivar Melody was used and as antagonistic bacteria 10 different bacteria were chosen: Serratia plymuthica A30 (NR), Flavobacterium sp. strain B17 (A3), Agrobacterium sp. (A6), unsequensed bacteria isolated from potato root (A4), Serratia j5h9 (S1), Alcaligenes faecalis (R8), Bacillus M1ju27 (BC1), Bacillus S3H53 (BC2), Burkholderia M1423 (BK3) and Pseudomonas S2h50 (PS3). Dickeya solani and Pectobacterium carotovorum were used as pathogens. Although BC1, BC2, S1 and BK3 antagonists did not influence negatively the potato in vitro seedling growth they did not, however, properly prevent soft rot of in vitro plants. Further studies on preventing soft rot of in vitro plants is needed.

The common lilac is one of the oldest cultivated ornamentals in Finland. The basic form of common lilac spread here in the beginning of the 18th century and lilac cultivars came in the mid-19th century. The aim of this study was to create DNA fingerprints for selected un-named common lilac individuals found in parks of Helsinki. The second objective was to find out the spread and cultivation history of common lilac in Finland. The hypothesis was that the common lilac was introduced and dispersed via Turku and Viapori. This was tested by comparing the DNA fingerprints of old lilac shrubs growing in historical sites with each other. DNA fingerprints were created for 88 samples using nine microsatellite markers The diversity of the microsatellite markers and the lilacs were evaluated by the effective number of alleles, expected heterozygosity and PIC values and AMOVA, respectively. Cluster analysis and a UPGMA dendrogram allowed the detection of identical samples. A total of 35 alleles were found and each of the nine loci was polymorphic. The effective number of alleles ranged from 1.17 to 4.83. The expected heterozygosity ranged from 0.14 to 0.79. The markers SV2, SV4 and SV1 had the highest PIC-values, more than 0.5. The analysis of molecular variance (AMOVA) showed significant level of differentiation between the clustered groups. The variation is explained by differences between and among the groups. The common lilac material studied was diverse. Microsatellite markers proved to be suitable for the study of Syringa vulgaris –species. Cultivar identification was complicated by missing amplification products. One local shrub was identified as the old French cultivar 'Congo'. The samples from historical sites connected to Turku and Viapori did not show any consistent differences, so the data do not support the hypothesis of two old lilac populations.