Field of Study – Biology (N 010)

More than 1,000 cases of foodborne parasitic infections are reported in the EU every year. The impact of foodborne parasitic infections on human health varies considerably depending on the species of parasite, ranging from mild illness to severe illness and possibly death. Predatory mammals are widespread in Europe and are hosts to a wide range of parasites. It is estimated that predatory mammals host approximately 43% of human infectious agents and are susceptible to a wide range of pathogenic microparasites. Ecological factors, together with environmental changes, mainly due to human activities, can increase the risk of parasite transmission between wildlife, domestic animals and humans. Control of foodborne parasites is therefore a high priority for quality assessment in slaughterhouses and food companies, and the role of predators as potential hosts of these parasites can help to understand the routes of transmission of infections and the measures to control them.

Due to their dietary habits, predators are hosts to many parasitic groups, including those dangerous to humans. As many wild predators increasingly visit human populated areas and come into contact with domestic animals, the likelihood of outbreaks of various parasites is high.  Domestic cats and wild felids are important hosts of Sarcocystis, Toxoplasma protists and Toxocara nematodes. Toxoplama gondii is a zoonotic pathogen of worldwide importance and has been extensively studied, but recently there has been almost no scientific studies on this pathogen in Lithuania, whose definitive hosts are cats. Globally, there is still a lack of studies assessing the prevalence of T. gondii in samples from wild felid predators. Toxocariasis is a well-known zoonotic disease caused by Toxocara nematodes and is mainly children are infected through dirty hands, unwashed fruit and vegetables. Cats spread Toxocara cati and Toxascaris leonina, while the infection rates of these parasites in urban environments in Lithuania have not been studied in detail.

The role of wild and domestic feline predators in the distribution of Sarcocystis, Toxoplasma and Toxocara parasites

Samples of Eurasian lynx (Lynx lynx), Spanish lynx (Lynx pardinus) and domestic cats are to be tested for these parasites. The diversity of samples planned to be tested is notable, with intestinal and faeces samples from the Eurasian lynx in Lithuania, faeces samples from domestic cats, and environmental samples collected at winter houses set up at stray cat feeding sites in Vilnius, at playgrounds and in sandboxes. DNA samples extracted from excrements of Spanish lynx will also be analysed in collaboration with Iberian scientists. Faecal samples from the Eurasian lynx will be collected in collaboration with scientists from the Nature Research Centre, Laboratory of Mammal Ecology. Intestinal samples and muscles of the Eurasian lynx will be collected in collaboration with the Tado Ivanauskas Zoological Museum, the national institution responsible for the monitoring of dead and injured wild animals. Parasites will be isolated and concentrated using traditional morphological-parasitological methods. Species richness and distribution of the parasites will be revealed using DNA analysis techniques and bioinformatic analysis. The results obtained will be useful for the assessment of the distribution of parasites of importance for humans and domestic animals in natural and urban environments. Based on investigations described, 4-5 scientific papers are planned to be published.

Climate change and the intensification of environmental conditions pose challenges to plant productivity and survival. Due to unusual temperature fluctuations (including sudden frost episodes), drought, soil salinity, and heavy metal pollution, plants experience abiotic stress, which reduces yield and threatens food security. Therefore, it is essential to deepen knowledge on plant resistance mechanisms and develop innovative plant protection strategies.

Plants adapt to unfavorable environmental conditions through physiological, biochemical, and genetic mechanisms. In recent decades, there has been a growing number of studies aimed at understanding the mechanisms of plant responses to abiotic stress (Rouphael & Colla, 2020). Significant attention is given to the functioning of the antioxidant system, signaling pathways (including phytohormones), gene expression, and metabolite analysis (Mittler, 2017; Verma et al., 2020). Alongside fundamental research on plant stress mechanisms, intensive studies are being conducted to explore genetic, physiological, biochemical, and agronomic modifications of these mechanisms. It is now crucial that these approaches are not only innovative but also sustainable (Zhao et al., 2021; Borrelli et al., 2018).The aim of this study is to analyze the physiological and biochemical responses of plants to abiotic stress and explore ways to enhance their tolerance. Molecular, cellular, and ecophysiological adaptations will be investigated during the doctoral studies, with particular attention to the activity of antioxidant systems, regulation of signaling pathways, and the search for innovative plant protection measures. It is expected that the research results will contribute to the expansion of fundamental knowledge and the development of practically applicable methods that will help ensure sustainable agriculture, higher yields, and plant adaptation to changing environmental conditions.

The planned research will be conducted under controlled laboratory conditions. The effects of model unfavorable environmental conditions and growth regulators on the functioning and productivity of economically valuable plants will be assessed using physiological-biochemical and morphometric methods.

The doctoral candidate is expected to participate in international events and training. The research findings will be disseminated at international scientific conferences and published in international scientific journals indexed in Clarivate Analytics Web of Science (CA WoS).

Plant pathogens are among the most important components of the microbiome and have a major impact on both ecological and evolutionary processes in host plants. Phytopathogenic micro-organisms (bacteria, fungi) also cause significant economic losses in many parts of the world, with plant diseases accounting for up to 30% of the world’s crop yields, resulting in billions of dollars of losses each year. This has led to a particular focus on the interaction of pathogenic microorganisms with vulnerable plants. Recent research worldwide, including in Europe, is now mainly focused on the specific virulence factors that affect plant health. A better knowledge of the characteristics of pathogenic microorganisms, and an understanding of population structure and dynamics, may lead to the development of more effective control measures and more advanced and specific diagnostic protocols.
Research on plant pathogens causing plant diseases in Lithuania has been fragmented in recent years, with too few studies being conducted. However, they are important in epidemiological terms, as research would provide new information on the distribution of pathogens in Lithuania and, more broadly, in Europe. A better understanding of the structure and dynamics of pathogenic microorganism populations could lead to the development of more effective control measures and more advanced and specific diagnostic protocols. The aim of the research to be carried out is to use molecular biology techniques to identify and genetically characterise the pathogen(s) in host plants and to assess their virulence factors.
This work would contribute to the 2022–2026 scientific research and experimental development programme of the Nature Research Centre “Dispersion of harmful substances, pathogens and other stressors in a changing environment in the context of risk assessment and remediation (POLLUTION)”.

The impact of factors caused by climate change on the functioning of Earth’s organisms and the state of ecosystems is currently a globally relevant topic. Climate change is believed to cause more frequent extreme events, including heavy rainfall, strong winds, heat waves and droughts, which can disrupt plant growth and make plants more vulnerable. Climate change studies show that many plants will be more stressed and less productive in the future. It is predicted that the yield of agricultural crops may decrease by several tens of percent during hot growing seasons. Therefore, studying the reaction of plants to changing conditions is important not only in a fundamental, but also in a practical sense.

Studies have shown that higher than normal temperatures lead to physiological and morphological changes in the plant. They accelerate the life cycle of plants, plants mature faster, so the intensity of photosynthesis changes and the yield decreases. As the competitive conditions of plants change under the influence of climate change, there is a need to strengthen the vital powers of agricultural plants. There is a lack of information on how stressful conditions will affect the physiological responses of plants and what environmentally friendly measures can be useful to reduce the harmful effects on the formation of reproductive organs.

Research will be conducted under natural field conditions and model conditions in the laboratory. Biostimulants will be used to search for means of controlling the processes that determine the productivity of agricultural plants. The effects of model climate change conditions and biostimulants on the functioning and productivity of economically useful plants will be assessed using physiological-biochemical and morphometric methods. Modeling the forecasted climate conditions will allow to study the possible impact on the sustainability of the resource and to search for measures to protect it.

Participation of the doctoral student in international scientific events, courses, and trainings is expected. The results of the work will be published at international scientific conferences and published in Clarivate Analytics Web of Science (CA WoS) referenced scientific journals.