Browsing by study line "Växtproduktionsvetenskap"

Grain legumes are grown on less than 2% of the arable area of Europe, while large quantities of soybean and soymeal are imported for feed for pigs and poultry. Crop rotations need diversifying by adding grain legumes for soil health and for the break-crop effect, lowering pest, disease and weed pressures in the subsequent crop. The economic effects are of interest from adding legumes to crop rotations and can be evaluated by modelling crop rotations and comparing the means of the gross margins (GM) from the rotations. In Finland, cereal-based crop rotations dominate the important crop growing areas of Southwestern Finland. The most common rotation during a five-year-period can consist of a cereal monoculture with two or more cereal species. The largest potential for diversification in crop rotations can be found on pig, poultry, and cereal farms. Modelling of grain legumes in crop rotations has previously been done for Västra Götaland in Sweden, Brandenburg in Germany, Calabria Italy, eastern Scotland in the United Kingdom, and Sud-Muntenia i Romania. The aim of this work was to create modelled crop rotations for Southwestern Finland to evaluate the gross margin, NO3-N-leaching, and N2O-emissions of the crop rotations. Yields were modelled for a ten-year period following actual yield fluctuations. They were analysed and there were no significant differences in gross margin detected in the crop rotations, whether they were a legume or an all-cereal rotation. Significant differences were found in N2O-emissions between the crop rotations

Perunalla on viime vuosien aikana havaittu tummia nekroottisia oireita mukulan kuoressa ja oireiden ulkonäön perusteella oireita on alettu kutsua kuoppataudiksi. Kuoppatauti voi näyttäytyä hyvinkin eri asteisena ja sitä voivat aiheuttaa monet erilaiset mikrobit. Tässä työssä tutkin Boeremia ja Fusarium -sienten tunnistamista perunanäytteistä PCR-menetelmällä sienilaji- tai sukuspesifisten PCR-alukkeiden ja geelielektroforeesin avulla. Tutkimusmateriaalina oli kuoppaoireisista perunaeristä keväällä 2021 saatuja mukulanäytteitä. PCR-tuotteet lähetettiin sekvensoitavaksi. Saatuja DNA-sekvenssejä verrattiin geenipankissa oleviin sekvensseihin BLASTn-menetelmällä ja tuloksista pääteltiin, mitä lajia kukin näyte-DNA edusti. Sen toteamiseksi, ovatko mukuloista eristetyt sienet todella kuoppataudin (ainoita) aiheuttajia, tehtiin taudinymppäyskokeita viljelymaljoilla kasvatetuilla sienillä. Terveiden mukuloiden pintaan tehtiin kolhuja, joihin ympättiin sienikasvustoa ja mahdollisten oireiden kehitystä seurattiin usean viikon ajan. Saatuja oireita verrattiin alkuperäisissä näytteissä havaittuihin oireisiin. Tutkimuksen tavoitteena oli selvittää mitkä patogeenit voivat aiheuttaa siemenperunoille nekroottisia ja väriltään tummia kuoppia. Inokulointikokeen tuloksia analysoitaessa todettiin tilastollista merkitsevyyttä (p< 0.01) ensimmäisen aikapisteen mittauksissa kontrollin ja Boeremian S- ja K-isolaattien välillä sekä kontrollin ja Juxtiphoman välillä. Toisen aikapisteen mittauksissa tilastollista merkitsevyyttä (p< 0.01) todettiin myös kontrollin ja Fusariumin välillä. Tulokset viittaavat siihen, että nämä kuoppaoireisista perunoista eristetyt sienet voivat aiheuttaa tautioireita perunan mukuloissa

Potato (Solanum tuberosum L.) is the world's third most important food crop, and its biggest threat is late blight caused by the fungus Phytophthora infestans (Mont.) de Bary. Although plant breeding has been aimed at developing resistant varieties, the use of fungicides is still the main control method. Breeding has the potential to produce functional and sustainable varieties, but its slowness and the adaptive nature of the pathogen make development challenging. Along with breeding and fungicides, different management practices, and prediction and monitoring models based on understanding the epidemiology of the pathogen and the combined effects of weather conditions, are means to develop more sustainable potato cultivation. In Finland, the Potato Research Institute conducts variety testing of potatoes. In the variety trials carried out in 2019 and 2020, the susceptibility of different potato varieties to late blight and the progression of foliar blight during the growing season were monitored. In addition to late blight resistance, an important criterion for the usefulness of the varieties tested is the yield level, which is examined in the trials. Differences were observed between the varieties in terms of foliar blight and the speed of its progression between the years. In both years, the foliar blight epidemic appeared later than expected in the trial area. The main reason for the delayed appearance of foliar blight was the weather conditions during the growing season. Late starch potato varieties proved to be the most resistant to foliar blight in the trials, and the weakest foliar blight resistance was observed in food potato varieties. Differences were also observed between the varieties in terms of 1000 tuber weights and tuber blight. Variety selection and weather conditions during the growing season have a significant impact on late blight pressure and the amount of damage caused. The most important characteristic of a variety is the yield, which was not measured in the experiments. Variety research conducted in Finland is important because the late blight resistance and agronomic characteristics of varieties coming from mainland Europe may not necessarily correspond to the information provided by the breeder in Finnish conditions. In the future, the development of integrated plant protection will play an increasingly important role in controlling P. infestans epidemics, as single actions will not provide sustainable solutions.

The biological control of carrot psyllid (Trioza apicalis Förster (Hemiptera: Triozidae)) was the focus of this study. The carrot psyllid is an important pest that causes significant yield loss. There is a lack of knowledge of the biological control of carrot psyllid with predators. In a recent study, larvae of Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) and adult Anthocoris nemoralis Fabricius (Heteroptera: Anthocoridae) were used as biological agents. The field research was carried out in Western Finland in the year 2021. The flight peak was monitored with yellow sticky traps, and predators were applied at the beginning of the flight peak. The number of carrot psyllids’ nymphs and eggs was calculated in the biocontrol treatments as well as untreated controls and chemical control treatments and results were compared. Due to severe drought during the field experiment, biocontrol treatments were studied also in semi-field conditions in the pallet collar cultivation experiment. The number of predators per square meter in the semi-field experiment was the same as in the field experiment and the effect on the controlled amount of carrot psyllids was observed. Both results were analysed with SPSS-program. According to the results, the combined treatment with C. carnea and A. nemoralis (Anthocoridae), where C. carnea were released one week later than A. nemoralis, decreased statistically significantly the number of carrot psyllids’ eggs. The C. carnea treatment or A. nemoralis (Anthocoridae) treatment alone did not reduce the number of eggs or larvae. There is no previous research on the biological control of carrot psyllid, so there is no background literature on the subject. The research aimed to get information on the biological control of carrot psyllid and that goal was achieved. It is essential to do further research on this subject. The following aims might be to find out more information on predator density, the timing of the predator release, and the effects of different predators’ combinations in the biological control of carrot psyllids.

Strawberries and raspberries have high demand in Europe and mostly consumed as fresh. Berries are highly perishable and so, their postharvest physiology and shelf life are important. Packaging is needed to keep the berries in good quality during the time in storage. Plastic clamshells are the commonly used type of packages for the berries but there are environmental concerns due to the heavy disposal of plastics. To overcome this problem, a fiber package is going to be introduced. It is biodegradable, biobased, made with renewable raw material and the final product is recyclable. This research focused on the mentioned fiber package and its functionality as a berry package and as possible replacement for plastic (RPET) clamshells. Homogenous batches of raspberries (Rubus idaeus) and strawberries (Fragaria × ananassa) were stored in plastic packages and fiber packages at two different temperatures (+3 °C and +17 °C/+16 °C). Decay incidence, weight loss, surface area of the berry, color, firmness, total soluble solid concentration, acidity, and package staining were measured over the storage period. Results showed that berries stored in fiber packages at +3 °C had higher soluble solid concentrations than the berries stored in plastic packages at the same temperature. Berries stored in fiber packages at both temperatures showed higher weight losses. Fiber packages absorbed more moisture from raspberries and strawberries than plastic packages. However, raspberries can be kept upto 8 days and strawberries can be kept upto 5 days under the marketable condition in fiber packages at +3 °C.

Abstract Nuclear bodies (NB) have been studied for their importance of being one of the sites for gene regulation activities. RADICAL INDUCED CELL DEATH1 (RCD1) has proven to be a potential nuclear protein in A.thaliana that localizes to NB. It can interact with different transcription regulators responsible for many physiological functions. One of which is light signaling. Hence, it shares mutual functions with some phytochrome photoreceptors (PHYs), e.g., PHYB. It also contains intrinsically disordered regions (IDRs) that stabilize RCD1 protein upon phosphorylation. This study aims to examine the colocalization events of RCD1 that coexpressed with PHYB in full-length RCD1 complementation line and domain deletion lines, given the fact that both RCD1 and PHYB have previously shown mutual interaction with some of PHYTOCHROME INTERACTING FACTORS (PIFs). To achieve this aim, the colocalization of Venus-tagged RCD1 and Green fluorescent protein (GFP)-tagged PHYB using confocal Microscopy was performed. Another objective is to study the phosphorylation effect of one of the IDRs between WWE and PARP-like domain -IDR2- on RCD1 NB localization. Two phosphomutants -non-phosphorylatable and phosphomimetic- constructs were transiently and stably expressed in the rcd1-4 background. Furthermore, they were screened using Confocal Microscopy. We were able to see the colocalization events in 2 domain deletion lines, RCD1-∆WWE-3xVenus and RCD1 ∆PARP 3xVenus. On the other hand, we could not see any colocalization in the RCD1 ∆RST 3xVenus, which indicates the importance of the RST domain in the colocalization. In addition, phosphorylation was found to affect the abundance of RCD1 protein in both transiently and stably expressed lines. Our study showed non-phosphorylatable forms of IDR2 having a higher abundance of RCD1 NB than the control line RCD1-3xVenus, whereas phosphomimetic IDR2 showed no signal. Collectively, Our experiments showed the effect of phosphorylation on RCD1 NB localization and the importance of the RST domain in the colocalization of RCD1 with PHYB.

Faba bean (Vicia faba L.) is a grain legume crop, its seeds are a generous source of plant protein for both food and feed. In addition to having a high nutritional value, faba beans are an essential part of a sustainable cropping system. Faba bean increases the biodiversity of crop rotation, and due to its' superior symbiotic nitrogen fixation, it reduces the need for chemical nitrogen fertilizers. Due to climate change, drought is predicted to increase during the growing season, especially in middle and high latitudes. Drought limits the growth of crops and reduces both grain and straw yields. Faba bean is a cool-season crop, and it has adapted to cool and moist conditions and has a low tolerance to water deficit. The main aim of this study is to determine whether Rhizobium leguminosarum inoculation improves adaptation of faba bean to water deficit. In addition, the study analyzes the effect of chemical nitrogen fertilizer on adaptation to water deficit and compares these results. The research was conducted under controlled greenhouse conditions and field experiment. In the greenhouse experiment, the effect of three different moisture treatments with field capacities of 100%, 45%, and 20% was compared on the growth between three different faba bean varieties. The genotypes used in the greenhouse experiment were Aurora, which is sensitive to water deficit; Mélodie, which has an efficient water absorption capacity; and Vire. Plants received three different nitrogen treatments: rhizobial inoculation, synthetic nitrogen fertilizer, and control that was not given nitrogen treatment. In the field experiment, a Finnish genotype, Sampo, was used, and the effects of four different nitrogen treatments on its growth were compared. The nitrogen treatments were inoculation, synthetic nitrogen fertilizer, a combination of these, and an untreated control. In the greenhouse experiment, water deficit and synthetic nitrogen fertilizer significantly reduced the number of active root nodules of the faba bean, while rhizobial inoculation increased the number of root nodules even under dry conditions. At 20% field capacity, inoculation increased shoot dry weight by 38%, while synthetic nitrogen fertilizer increased shoot dry weight by 26%. Synthetic nitrogen fertilizer, on the other hand, increased leaf area and SPAD results more than rhizobial inoculation. Leaf temperature raised as the stomatal conductance decreased under water deficit. Increasing the amount of nitrogen either by inoculating with rhizobia or synthetic nitrogen fertilizer promotes the growth of faba bean under water deficit conditions. Synthetic nitrogen fertilizer increases the adaptation of faba bean to water deficit slightly more than inoculation. Inoculation can ensure the formation of root nodules and efficient nitrogen fixation under water deficit.

Tiivistelmä  Referat  Abstract Lettuce (Lactuca sativa L.) may accumulate high amounts of nitrate in the hydroponic NFT-cultivation system. Accumulation is known to increase under low light conditions, and thus high nitrate content causes problems in year-round lettuce production in Finland. Nitrate is classified as a harmful food additive, and the regulation (194/97) of the European Commission requires the Member States to monitor the nitrate content of commercial lettuce. Hence, to control the nitrate content, farmers have requested an efficient method that does not shorten the shelf-life or negatively affect the quality of lettuce. In the earlier studies, root-applied glycinebetaine (GB) was shown to reduce lettuce nitrate content and increase the contents of amino acids and minerals. The present study aimed to investigate, whether glycinebetaine can serve as a precise method to control lettuce nitrate content in commercial-scale greenhouse production. Glycinebetaine 10 mM was applied into the nutrient solution twice at three days intervals, and lettuce was exposed to treatment during the last six growing days before the harvest. Plant samples were collected every second day for 14 days after the first GB application, and samples from nutrient solution were collected simultaneously. The reduction of GB from the nutrient solution was monitored. The fresh weight of the plants was weighed during the harvest, and contents of nitrate, dry matter, minerals, amino acids, and GB in the plant samples were analyzed. Root-applied GB reduced lettuce nitrate content by over 29 % in comparison to control plants. The total contents of hydrolyzed- and free amino acids were increased. The total content of essential amino acids was increased up to 14 % following the GB treatment. Also, the contents of minerals in the lettuce leaves were altered. The potassium (K+) content in lettuce was reduced by over 40 % after GB application. Lettuce accumulated the applied GB and leaf GB content was 7 mg kg-1 fresh lettuce at the highest. Root-applied GB reduced the fresh weight of the harvested lettuce, but all plants reached the commercial size (>100 g) during the typical commercial growing period of 41–43 days. The result of the present study proved that GB is a practical method to control nitrate content and the quality of lettuce on commercial-scale lettuce production. Glycinebetaine was detectable in the nutrient solution for three days after application and thus, continuously maintained lower nitrate content in plants requires continuous GB application in the commercial lettuce production. The reduction of the nitrate content was significant six days after the first GB application, which indicates that a six-day treatment period is required.

Many noble hardwood species of boreal and temperate climate zones will experience increased selection pressure for adaptive traits as climate change proceeds. This will cause shifts in the timing of phenological events such as budburst in spring. Shifts in phenology may disrupt interaction between species and their environment as well as interaction within and between species. Changes in the timing of annual life cycle traits may threaten species’ current fitness and potential to adapt to future climates. The rate and magnitude of phenological shifts will increase along with increasing temperatures. To adapt to changing environmental conditions, species need to possess adaptive variation in life cycle traits. In small and isolated populations at northern margins of species distribution, variation in adaptive traits is threatened by low genetic variation, low gene flow and genetic drift. To preserve the adaptive potential of noble hardwood populations in Finland, ex situ gene conservation collections are established where genetic resources are conserved as living trees. To characterize the adaptive potential currently present in Finnish gene conservation collections of European maple (A. platanoides L.), small-leaved linden (T. cordata Mill.) and European white elm (U. laevis Pall.), the amount of current phenological diversity should be evaluated. For this purpose, budburst progress in the collections was tracked by phenotypic observations on budburst phenological phases in relation to accumulating temperature. The data did not allow for analysis of variance between origin populations; therefore, a more conservative approach was chosen where conserved genetic resources were assessed by examining budburst differentiation between groups of origin populations. The level of differentiation in budburst temperatures is used as an indicator of spring phenological diversity to determine if the conserved origins are adapted to the same spring temperature range. No significant differentiation was found in the timing of budburst between groups of origins. Therefore, the conserved origins are presumed to be adapted to the same spring temperature range within their respective species distribution in Finland. However, low phenological diversity may magnify the threats imposed to these species by climate change. Genetic studies are recommended for deeper understanding of underlying genetic diversity and adaptive potential of the stored genetic resources.

Abstract Background. Faba bean (Vicia faba L.,) is a protein-rich grain crop and a good source of many nutrients. However, the productivity and composition of this crop can be limited by several biotic and abiotic stresses. Acid soil leads to a reduction in water uptake, and influences on major biological and chemical processes. However, some plants can manage stress. Mostly, low pH reduces plant vegetative organs and a has a negative effect on physiological processes such as gas exchange, photosynthesis, chlorophyll concentration, and transpiration. The aim of this study was to find homolog genes in close spp. and o test selected gene response as a factor in resilience to rootzone acidity in Vicia faba L. Methods. Four faba bean genotypes were selected for our experiment based on germplasm screening in aquaponic conditions from a previous study. According to obtained results of morpho-physiological measures from a previous experiment, IG11204 and Bourdon showed tolerance to acid only. DULUC is tolerant to acid and Al treatments. In contrast, Nora38 demonstrated susceptibility to both stresses. Selected genotypes were grown under the same experimental conditions in order to proceed with samples for further analysis (total RNA extraction, cDNA synthesis, RT-PCR, gel-electrophoresis, validation of selected gene by RT-qPCR). Results. Selected genes have been identified as hub genes in A. thaliana (alternative oxidase 1A, glutamate dehydrogenase 1, zinc fingers superfamily protein), which demonstrated an increase in expression levels under acidic pH stress. We have found homolog genes in the Hedin cultivar. Selected homolog gene were used to check its expression in four genotypes under Al3+ and acidic stresses using RT-qPCR. Finally, up-regulation of the GDH1 was detected by acid and also occurred by Al3+ treatments. Discussion. Our analysis of gene expression revealed that GDH1 was expressed differently between control and treated groups. However, its activity was detected for both stresses. The expression of GDH1 transcripts in this study, also concurs with findings where GDH1 in A. thaliana were expressed under Al3+ stress. Furthermore, it was confirmed that they are novel Al3+ resistance genes, which are regulated by the transcription factor STOP1 (sensitive-to-proton-rhizotoxicity1). GDHs are involved in stress tolerance, and pH-regulated metabolic pathways – GABA shunt. It participates in the regulation of cytosolic pH, carbon fluxes into the TCA cycle, nitrogen metabolism, deterrence of insects, protection against oxidative stress, osmoregulation and signaling in plant cells under different stress conditions. The GABA shunt is enhanced by stresses, which cause cytosol acidification. Genes expressed in conditions of low pH partly overlap with those expressed in plants exposed to Al3+ stress. Generally, acidic soil is associated with the co-occurrence of Al3+ and H+ rhizotoxicities.