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Sea buckthorn Hippophae rhamnoides and fruit flies Rhagoletis batava: Search for volatile semiochemicals involved in pest attraction /
No full textRhagoletis batava (Diptera: Tephritidae), is the most important pest of Hippophae rhamnoides fruits. For detection and monitoring of R. batava, traps supplied with nonspecific attractants are used. Thus, new, more specific attractants for environment-friendly pest control are needed. Such attractants could be fruit-related semiochemicals that are involved in the host location by flies. Behavioural Y-olfactometer tests revealed that R. batava males were attracted to ripe fruit odour, while females preferred unripe and semi-ripe fruits. Thermal desorption gas chromatography-mass spectrometry (GC-MS) analysis revealed substantial quantitative and qualitative changes in volatiles between unripe and ripe fruits. In the unripe fruit emission, 41 volatile compounds were isolated, whereas 64 compounds were sampled from the ripe fruits. The total amount of volatiles increased five times during the fruit ripening. Gas chromatography-electroantennogram detection (GC-EAD) and GC-MS analyses of the fruit headspace volatiles revealed at least 26 compounds in unripe and 27 compounds in ripe fruits eliciting antennal responses of R. batava for both sexes. The fruits of these two ripening stages differed qualitatively in the single EAD-active compound only, i.e., 3-methylbutyl 2-methylpropionate. Esters were the most abundant volatiles, composing 84% and 93% of EAD-active compounds in the emissions of unripe and ripe fruits, respectively. Based on the persistent EAG responses, 17 compounds were selected as the most promising candidates for kairomone attractants of the sea buckthorn pest R. batava
Impact of edaphic and climatic factors on Thymus pulegioides essential oil composition and potential prevalence of chemotypes /
No full textIntraspecific chemical polymorphism is characteristic of essential oil bearing Thymus pulegioides (Lamiaceae). Soil chemical composition and climatic conditions can influence not only quantitative and qualitative composition of essential oils, but also on prevalence of different chemotypes in space. The purpose of study was to determine the impact of edaphic and climatic factors on T. pulegioides essential oil composition and potential chemotypes prevalence. It were investigated 131 habitats of T. pulegioides in all ten climatic sub-districts of Lithuania. Essential oils were isolated by hydrodistillation and analysed by GC-FID and GC-MS. The content of humus was estimated by oxidation method, the content of mobile potassium (K2O) and mobile phosphorus (P2O5)-flame photometry using 0.2 M HCl solution, the soil pH-electrometrically and 15 elements of soil-by energy-dispersive X-ray fluorescence. The meteorological data (temperature, rainfall, photosynthetically active solar radiation and sunshine duration) were obtained from the meteorological bulletins. Results showed that humus in soil positively, manganese and cobalt-negatively influenced on the essential oil accumulation in T. pulegioides. Carvacrol was the most common compound in the essential oil of T. pulegioides; higher amounts of sulphur and mobile phosphorus, lower amounts of sodium in soil, higher rainfall in blooming period are favourable for this compound and for potential prevalence of carvacrol chemotype. Geraniol was frequent in the eastern and the central part of Lithuania, where the temperature in vegetation season is higher, and in soils characterised by higher and lower amounts of sodium and chlorine, respectively. Thymol, linalool and alpha-terpinyl acetate were rare. Edaphic and climatic conditions can differently influence on essential oil yield and chemical composition of species as well as on potential prevalence of different chemotypes of same species in space
C-14 and other radionuclides in the environment in the border region of Lithuania before the start of the Belarusian nuclear power plant operation /
No full textIn this paper, we analyze the background activity of anthropogenic radionuclides (C-14, H-3, Cs-137, and Pu-239,Pu-240), emphasizing C-14 content, in terrestrial and aquatic ecosystems in the Lithuanian border region before the commissioning of a new nuclear power plant in Belarus (BelNPP). In terrestrial samples, the C-14 concentration varied insignificantly-from 98.6 +/- 0.7 to 102.2 +/- 0.8 pMC, which is close to the C-14 level in atmospheric CO2. In aquatic samples, the C-14 concentration varied within wide limits from 76.9 +/- 0.7 to 99.6 +/- 0.6 pMC, depending on the ecological group of macrophytes. Various ecological groups of macrophytes have experienced the influence of a freshwater reservoir effect. This lowest C-14 content in submerged macrophyte species, within the limits of uncertainty, was very close to the specific activity of C-14 in DIC (78.6 +/- 0.6 pMC) in the water of the Neris River. The background C-14 values, together with the data on H-3, Cs-137 and 239,240Pu obtained in this study, can be used in the future to assess the contribution of the BelNPP conventional radioactive effluents to the levels of C-14 and other radionuclides in terrestrial and aquatic ecosystems of the transboundary region of Belarus and Lithuania
What can haemosporidian lineages found in Culicoides biting midges tell us about their feeding preferences? /
No full textHaemoproteus (Parahaemoproteus) parasites are transmitted by Culicoides biting midges. However, the natural vectors of only six of the almost 180 recognized Haemoproteus species have been identified. The aim of this study was to investigate wild biting midges naturally infected with Haemoproteus and to understand the interaction network between Culicoides and Haemoproteus in Europe. Culicoides were collected with UV light traps from different sites in Lithuania. Parous females were morphologically identified based on their wings and heads. PCR-based methods were used to detect the Haemoproteus DNA, and salivary gland preparations were analyzed for the presence of sporozoites. Of the 580 Culicoides analyzed, 5.9% were positive for Haemoproteus DNA, and sporozoites were found in two of 11 sampled biting midge species: Culicoides kibunensis and Culicoides segnis. The interaction network revealed that C. kibunensis and C. segnis are frequently associated with several Haemoproteus lineages. On the other hand, some Haemoproteus lineages were found to interact with only one Culicoides species. This was the first report of C. segnis being a competent vector for H. minutus TURDUS2, H. asymmetricus TUPHI01, H. majoris PHSIB1, and H. fringillae CCF3; and of C. kibunensis being a competent vector for H. belopolskyi HIICT1. Culicoides segnis and C. kibunensis are both important vectors of Haemoproteus parasites
Rediscovery of endangered species Laphangium luteoalbum (Asteraceae) in Lithuania /
No full textLaphangium luteoalbum (Asteraceae) is a widely distributed species native to Eurasia; however, it is rare or endangered in some regions of Europe and included into the lists of protected species. In Lithuania, Laphangium luteoalbum was recorded in the southern part of the country, mainly along the banks of the Nemunas River in the 20th century. In contrast, it was found only in the 19th century in the western part of the country. During the research in Curonian Spit National Park (Neringa, western Lithuania), a relatively large species population was found in the transition zone between the dune grassland and wet dune slack habitats. The total population in 2020 consisted of about 500 individuals distributed over an area of about 310 m2. We assume that the seeds of this wind-dispersed plant may have been transferred from other regions of Europe by the wind. However, it cannot be excluded that the plants found are descendants of populations previously recorded in the country. The species is most threatened by the loss of wet, open sandy habitats due to eutrophication of water bodies and subsequent changes in bank vegetation. Laphangium luteoalbum was classified as data deficient (DD) in the last assessment according to the IUCN criteria. Still, a reassessment based on the current data indicates that the species should be considered critically endangered (CR) in Lithuania
Keturios Tischeriidae rūšys Kolumbijoje, tarp jų viena nauja Astrotischeria: ar ne per mažai tokiai biologine įvairove garsiai šaliai?
No full textUntil 2019, Tischeriidae, or trumpet moths, were totally unknown in Colombia. Here we review all currently available scanty data on the Colombian Tischeriidae and describe Astrotischeria recta Diškus, Mey & Stonis, sp. nov., a new species of trumpet moths from Valle de Cauca, Colombia. The new species is illustrated with photographs of the male genitalia, adults, and their habitats. In the current paper, we also briefly discuss the number of the Tischeriidae species in other Neotropical countries and provide renewed data
Solvothermal synthesis of calcium-deficient hydroxyapatite via hydrolysis of α-tricalcium phosphate in different aqueous-organic media /
No full textIn the present work, the effects of various organic solvents (solvent nature and fraction within the solution) and solvothermal conditions on the formation of calcium-deficient hydroxyapatite (CDHA) via hydrolysis of α-tricalcium phosphate (α-TCP) are investigated. The wet precipitation method is applied for α-TCP synthesis, and the hydrolysis reaction is performed in solutions with different water-to-organic solvent ratios under solvothermal conditions at 120 °C for 3 h and at 200 °C for 5 h. Ethyl alcohol, isopropyl alcohol, and butyl alcohol did not inhibit the hydrolysis of α-TCP, while methyl alcohol and ethylene glycol have a more prominent inhibitory effect on the hydrolysis, hence the formation of single-phased CDHA. From all the solvents analysed, ethylene glycol has the highest impact on the sample morphology. Under certain water to ethylene glycol ratios and solvothermal conditions, samples containing a significant fraction of rods are obtained. However, samples prepared with ethylene glycol are characterised by a particularly low BET surface area
Fire occurrence in hemi-boreal forests: Exploring natural and cultural Scots pine fire regimes using dendrochronology in Lithuania /
No full textFire is an important natural disturbance and a driver of hemi-boreal forest successional trajectories, structural complexity, and biodiversity. Understanding the historic fire regime is an important step towards sustainable forest management. Focusing on Lithuania’s hemi-boreal forests, we first mapped the potential natural fire regimes based on the relationship between site conditions, vegetation, and fire frequency using the ASIO model. The ASIO model revealed that all the fire frequency categories (Absent, Seldom, Intermittent, Often) are found in Lithuania. Scots pine forests dominated the often fire frequency category (92%). Secondly, focusing on a fire-prone forest landscape, Dzūkija, we analyzed the fire occurrence of Scots pine forest types using dendrochronological records. We sampled and cross-dated 132 Scots pine samples with fire scars from four dry forest stands (n = 92) and four peatland forest stands (n = 40), respectively. In total, the fire history analysis revealed 455 fire scars and 213 fire events during the period of 1742–2019. The Weibull median fire intervals were 2.7 years (range 1–34) for the dry forest types and 6.3 years (range 1–27) for the peatland forest types. Analysis pre-and post-1950 showed the Weibull median fire interval increased from 2.2 to 7.2 for the dry forest types but decreased from 6.2 to 5.2. for the peatland forest types. A superposed epoch analysis revealed significant precipitation fluxes prior to the fire events after 1950. Thus, the Dzūkija landscape of Lithuania has been strongly shaped by both human and naturally induced fires. The combination of theory (the ASIO model) with the examination of biological archives can be used to help guide sustainable forest management to emulate forest disturbances related to fire. As traditional forest management focusing on wood production has eliminated fire, and effectively simplified forest ecosystems, we recommend introducing educational programs to communicate the benefits and history of forest fires as well as adaptive management trials that use low-intensity prescribed burning of Scots pine stands
Geochemical study of the Iron Age settlement occupational layer and the early Roman Time agricultural layer at Voorthuizen, The Netherlands /
No full textThe application of geochemical analysis in archaeology provides a better understanding of ancient human activities. This paper presents the results of geochemical multi-element, LOI, MS, and geochronological analyses of a cultural layer at the Voorthuizen (The Netherlands) archaeological site. The study has revealed a difference in the geochemical composition of an occupational surface in the Iron Age settlement and an early Roman Time agricultural horizon. The former is enriched in Ba, Sr, Rb, Th, Cl, and Mg, while the latter displays elevated P, Pb, Ni, Mn, and V values. The study has provided a deeper insight into the agricultural techniques applied at the Voorthuizen site and on the so-called Celtic Fields, known as ancient field systems dating from the same period and widespread throughout north-west Europe. It seems that household waste was not used as a fertilizer at Voorthuizen, while the application of manure is characteristic of Celtic Fields. However, phosphorous values in the Voorthuizen agricultural horizon are comparable to those in the Celtic Fields, suggesting similar sources of P in both cases. Elevated Si and “mobile” Fe, Mn, V, Pb, As, and Sn, along with higher MS measurements, are indicative of the use of extra mineral matter for the fertilization of the Voorthuizen ancient arable field
Adaptive response of Saccharomyces hosts to Totiviridae L-A dsRNA viruses Is achieved through intrinsically balanced action of targeted transcription factors /
No full textTotiviridae L-A virus is a widespread yeast dsRNA virus. The persistence of the L-A virus alone appears to be symptomless, but the concomitant presence of a satellite M virus provides a killer trait for the host cell. The presence of L-A dsRNA is common in laboratory, industrial, and wild yeasts, but little is known about the impact of the L-A virus on the host’s gene expression. In this work, based on high-throughput RNA sequencing data analysis, the impact of the L-A virus on whole-genome expression in three different Saccharomyces paradoxus and S. cerevisiae host strains was analyzed. In the presence of the L-A virus, moderate alterations in gene expression were detected, with the least impact on respiration-deficient cells. Remarkably, the transcriptional adaptation of essential genes was limited to genes involved in ribosome biogenesis. Transcriptional responses to L-A maintenance were, nevertheless, similar to those induced upon stress or nutrient availability. Based on these data, we further dissected yeast transcriptional regulators that, in turn, modulate the cellular L-A dsRNA levels. Our findings point to totivirus-driven fine-tuning of the transcriptional landscape in yeasts and uncover signaling pathways employed by dsRNA viruses to establish the stable, yet allegedly profitless, viral infection of fungi