Southeastern Bulgaria Research Articles

Yield and Yield-related Traits of Advanced Lines of Winter Barley

A field experiment was conducted at the Institute of Agriculture – Karnobat, Southeastern Bulgaria in three growing seasons. Ten advanced lines developed by experimental mutagenesis along with parent line and standard varieties Obsor and Emon were laid out in a complete block design with 4 replications. Variability and heritability for yield-related traits and grain yield were studied. There were significant differences among advanced lines for all studied traits. Heritability in broad sense ranged from 48.51 % for grain weight per spike to 79.36 % for spike length. The grain yield of advanced lines was significantly higher compared to the parent and varied from 5.34 t/ha in M5/14 to 6.28 t/ha in M5/14. Moreover, lines M5/1, M5/3, M5/10, and M5/19 had higher grain yield than the high-yielding standard variety Emon. Hence, using these lines in the breeding program of winter barley could lead to the improvement of grain yield.

Preservation and Promotion of the Cultural-Historical Heritage and the Settlement Culture (Following the Example of the Town of Kableshkovo, Burgas District, Bulgaria)

The town of Kableshkovo, Burgas district is located in southeastern Bulgaria, within the municipality of Pomorie and near the town of Nessebar. Many migrants from Aegean Macedonia and Thrace, as well as from Erkech (today's Kozichino) live in Kableshkovo. Nearby is the prehistoric settlement and necropolis "Kozareva Mogila", and as the birthplace of the partisan poet Atanas Manchev, Kableshkovo is known for its anti-fascist activities and privileged attitude of the rulers during the socialist period. The report examines the practices established in the town of Kableshkovo, Burgas region for the preservation of cultural and historical heritage and settlement culture.

Formation and characterization of acid mine drainage in the Madzharovo ore field, Southeastern Bulgaria

The formation of acid mine drainage (AMD) is a serious environmental problem in areas with mining and processing industries worldwide. Their generation is associated with chemical and biological processes of oxidation of sulfide minerals, mainly pyrite. Sources of AMD can be deposits of sulfide minerals and coal with a high content of pyrite sulfur, mining waste and some tailings. The impact of AMD on surface and groundwater in mining areas continues for decades after the cessation of extraction. An example of the negative impact of generated acid mine drainage on the state of surface waters is in the region of Madzharovo. Years after the cessation of mining, the waters at the discharge points "Momina Skala", "Harman Kaya" and "Pandak Dere" are characterized by low pH values and high concentrations of iron, copper, zinc, cadmium, lead and manganese.

The Language of the Border, the Minority of the Border -A study on the linguistic identity and alienation of minority in the Balkan Peninsula (POMAK)

The Balkan and Bulgarian rule of Ottoman Turkey (1396-1878) left a historical mark in several respects. The Pomak minority ethnic groups living in southeastern Bulgaria, western Turkey and northern Greece are the representative historical products of Ottoman Turkish rule over 500 years in this area. In particular, minority who believes in Islam, not Orthodox (Greek Orthodox or Bulgarian Orthodox), the main local religion, and who speaks their own non-bulgarian language, are at the center of alienation and discrimination. It is established and has suffered a lot in terms of language and culture. Currently, around 100,000 Pomak (mostly living in the area around Rodophe mountains in southeastern Bulgaria) are at the forefront of alienation of these languages and religions. Those who have not been incorporated into the mainstream society but are striving to continue their own religious and linguistic traditions can be regarded as an anthropological precedent that shows the most distinctive aspect of isolation at the boundaries of language and culture. The primary purpose of this study is to study the linguistic identity of Pomak and their alienation. In addition, it aims to study and preserve traces of these disappearing languages, and to study the sociolinguistic status of Pomak living in multicultural and multinational border areas within the borders of the European Union pursuing pluralism. The main facts revealed in this paper are as follows. 1. From a linguistic point of view, the Pomak language is most closely related to the Bulgarian language. However, from the viewpoint of the phonetic-phonology and morphology, it shows a linguistic characteristic that is closer to the ancient Bulgarian language, which shows a conservative language pattern, rather than the modern Bulgarian language, where the change to analytic language is already strong. 2. The use of three-element post-position definite articles based on s-, t-, and n- stems is a linguistic phenomenon observed today in the Bulgarian dialect. It can be regarded as a transitional phenomenon that appears as grammaticalization has not yet been completed amid the synchronic change of post position definite articles characteristic of Bulgarian, but these three elements of post-position definite articles are not only the concept of space but also the concept of time (especially connected with the present and the future, habitual action) in Pomak language. 3. <Assimilation-Bulgaria / Absorption-Turkey / Exclusion-Greece> is the position and attitude of the governments of the three main countries where the Pomak people live in.

Post-release settlement and survival of endangered European ground squirrel after conservation reinforcement

The spatial behaviour of 47 European ground squirrels (Spermophilus citellus) was investigated through radio-collars in the frame of a conservation project for population reinforcement in south-eastern Bulgaria. For the first time both translocated and resident individuals were collared. After the release, each individual’s movement was followed hourly through triangulation during the day and the sleep sites were localised by radio-tracking in the evening. The results showed that the translocated individuals had much larger territories in comparison with the residents. The males and the adults were significantly more mobile than the females and juveniles. Considerable relocation was observed in more than one third of the translocated individuals between the 5th and the 10th day after the release. The main reason for death was predation. The survival of the translocated individuals at the end of the first active season after the translocation was 79%. Recommendations for future Spermophilus citellus conservation translocations were drawn.

Variability, Correlation, and Path Coefficient Analysis of Grain Yield and Yield-Related Traits of Facultative Barley Accessions Grown Under Rainfed Conditions

A study was conducted during the period of three concessive years from 2016/2017 to 2018/2019 in the experimental field of the Institute of Agriculture - Karnobat, Southeastern Bulgaria with the aim to investigate the variability, heritability, and correlation between grain yield and yield-related traits of breeding lines of facultative barley under rainfed conditions and to select lines with desirable agronomic traits for including in further breeding work for the development of facultative barley varieties for Bulgarian environments. The traits: number of days to heading, plant height, spike length, spikelet number per spike, grain number per spike, grain weight per spike, and grain yield were recorded. The analysis of variance indicated significant differences between 6-rowed facultative barley genotypes in the studied traits. Most of the traits under the study showed the relatively low phenotypic and genotypic coefficient of variation. The estimates for heritability in broad-sense were high for the number of days to heading, grain weight per spike, and 1000-grain weight and very high for plant height and spike length suggesting a possibility for improvement of those traits through selection based on phenotype. Whereas low heritability of grain yield was found indicating that the phenotypic selection could be ineffective under these specific conditions. Grain yield of facultative barley accessions showed a significant positive correlation with spike length, spikelet number per spike, grain number per spike and grain weight per spike. The traits with the highest positive direct effect on grain yield were grain number per spike and 1000-grain weight while days to heading had a highly negative direct effect on grain yield. A combination of high heritability and high direct on grain yield in 1000-grain weight and days to heading shows that those traits may be used in early-generation selection in breeding of high-yielding facultative lines. The accession TX01D236 had a significantly higher grain yield compared to check varieties and could be included in future breeding work.

Five ixodid tick species including two morphotypes of Rhipicephalus turanicus on nestlings of Eurasian eagle owl (Bubo bubo) from south-eastern Bulgaria

BackgroundBirds are major hosts for many tick species (Acari: Ixodidae, Argasidae), and their role is especially important in transporting ticks over large distances along their seasonal migratory routes. Accordingly, most studies across Europe focus on the importance of avian hosts in tick dispersal, and less emphasis is laid on resident birds and their role in supporting tick life cycles. Eurasian eagle owls (Bubo bubo) exemplify the latter, but all the few studies on their tick infestation were carried out in Western Europe and even those did not involve a large sample size and did not assess infestation prevalence in natural habitats.MethodsIn this study, 320 ixodid ticks were collected from nestlings of Eurasian eagle owls during the period 2018–2020 in Bulgaria in south-eastern Europe. These ticks were analysed morphologically, and selected specimens molecularly based on cytochrome c oxidase subunit I (cox1) gene. The effects of environmental and habitat-related conditions and of the species of prey eaten by eagle owls on tick infestation were also evaluated.ResultsThe majority of ticks were identified as adults of Rhipicephalus turanicus (n = 296). In addition, 15 Hyalomma marginatum (three males, 11 nymphs and a larva), one female of Haemaphysalis erinacei and of Ha. punctata, and a nymph of Ixodes ricinus were found. Among R. turanicus, two distinct morphotypes were observed, but they do not form a monophyletic clade in the phylogenetic tree based on the mitochondrial gene cox1. We found a positive correlation between the total number of ticks on nestlings from a particular nest and the number of medium-sized to large prey mammals brought to the nestling owls. Also, the most important predictor for tick abundance was the effect of the extent of arable land (negative), while forests and grasslands contributed less, with no effect observed in case of urbanized areas and watercourses.ConclusionsThe intensity of tick infestation can be high on nestling Eurasian eagle owls (mean intensity 16.59 ticks/nestling). In this study, five different tick species were recorded, among which R. turanicus dominated. Two male morphotypes of this tick species were found, but their morphological differences were not reflected by genetic diversity or phylogenetic clustering. The most important factor determining tick abundance was the land-use structure.Graphical

Емпирично изследване на управлението на услугите на агроекосистемите в България (An Empirical Study of the Management of Agro-Ecosystem Services in Bulgaria)

Емпирично изследване на управлението на услугите на агроекосистемите в България (An Empirical Study of the Management of Agro-Ecosystem Services in Bulgaria)

New Byzantine Lead Seal from the Area of the Medieval Fortress of Rusokastro (South-Eastern Bulgaria)

This paper analyses a Byzantine lead seal discovered in 2019 and now residing in the Regional Historical Museum in Burgas (Bulgaria). According to the legend, it belonged to a Byzantine official Michael by name, who held the position of (imperial) protonotarios and judge. This seal originates from the area of the medieval fortress of Rusokastro located in south-eastern Bulgaria. The obverse depicts facing bust of St. Archangel Michael, nimbate, wearing mail armour, which is encircled with the border of dots. The image is framed with a partially preserved continuous circle. Archangel Michael holds a spear in his right hand, with its top part partially worn off by mechanical damage. To the right of the spear is well legible letter M, and to the left of the image, at the worn off flattened area of the field, there is a relatively well-preserved letter X, i. e. abbreviations of the name of St. Archangel Michael. On the reverse is an inscription in four lines reading: “+ Lord help Michael, (imperial?) protonotarios and judge.” The seal dates from the tenth to the early eleventh century.

On the “otter-fish producers conflict” in South-Eastern Bulgaria

Predatory mammals compete with humans for game, livestock and fish. The otter (Lutra lutra L.) inhabits the whole river system in Bulgaria, including fish ponds, coming into conflict with fish producers causing damage due to its feeding habits. To clarify the manifestations of the conflict, an anonymous questionnaire among fish farmers and workers was provided. According to the survey, the market-sized fish was affected the most (93.75% of the respondents) by otter’s attacks, to a lesser extent the juveniles - 63.75% and the broodstocks - 62.5%, respectively. In the current study, 43.75% of respondents claimed that weed fish also suffers damage. A total of 77.5% of the respondents have tried to overcome the problem. In the present study, there was no report for using a non-lethal method. It can be concluded that the "Otter-fish producers conflict" in Bulgaria will be mitigated if compensations are provided for the economic losses.

EUROPEAN BADGER (MELES MELES LINNAEUS, 1758) PREFERENCES TO THE TERRAIN EXPOSURE FOR DIGGING DENS IN SOUTHEASTERN BULGARIA

A total of 47 active badger burrows in the Southeastern Bulgaria were described in order to find whether there are preferences to terrain exposure for its digging activity. The most of the dens were found on terrain with south exposure - 23.4%, followed by these on the east and west side -19.15% each. The dens faced to these three directions, together with these to intercardinal directions connected with south, represented 80.85% of the active badger dens found. A tendency in the preference of the European badger to the southern exposure of the terrain for its digging activity in the region of South-eastern Bulgaria was established.

Population genetic structure and diversity of the East Balkan Swine (Sus scrofa) in Bulgaria, revealed by mitochondrial DNA and microsatellite analyses.

The East Balkan Swine (EBS) is the only indigenous pig breed in Bulgaria. We analyzed the mitochondrial DNA (mtDNA) control region and 21 microsatellite loci for 198 individuals from 11 farms in Bulgaria. Obtained 11 mtDNA haplotypes including three novel ones were grouped to two major clades, European clade E1 (146/198 individuals, 73.7%) and Asian clade A (52/198, 26.3%). The mixture of the two clades may have resulted from historical crossbreeding between the European and Asian pig breeds. Clade A was frequent in southeastern Bulgaria (Burgas Province), but less frequent or absent in northeastern Bulgaria (Varna and Shumen Provinces). The distribution of Europe- and Asia-specific haplotypes relative to EBS farm locations could be attributed to regional differences of breeding systems (e.g., crossbreeding with imported commercial pigs). A microsatellite analysis showed high heterozygosities for all the EBS farms, and negative inbreeding coefficients presumably due to crossing with commercial pigs or wild boars and/or efforts to reduce inbreeding by farmers. Bayesian clustering analyses showed that all farm populations are genetically well distinguishable from one another. Although diversity has been maintained by the efforts of farmers and a breeding association, the effective population size remains small, and conservation efforts should be continued.

Influence of Heat Stress and Physiological Indicators Related to It on Health Lipid Indices in Milk of Holstein-Friesian Cows.

The aim of the survey was to study the effect of heat stress (HS) on health lipid indices in milk of Holstein-Friesian cows. The study was conducted in a cattle farm with Holstein-Friesian cows in the region of Karnobat (Southeastern Bulgaria) in 2018. Cows were housed in semi-open free stall dairy barn, fed year-round ad libitum with a total mixed ration. The study included 22 cows on different parities studied in two periods - at thermo-neutral environment conditions and at heat stress, respectively, May and August. Extraction of milk fat was performed by the Rose-Gottlieb method. Conditions of HS lead to changes in the values of health lipid indices associated with a decrease in the values of Atherogenic index (AI), Thrombogenic index (TI), Lipid Preventive Score (LPS) and Desaturase (18) index (DI 18) and an increase in Health promoting Index (HPI), polyunsaturated fatty acids/saturated fatty acids (PUFA/SFA), unsaturated fatty acids/saturated fatty acids (UFA/SFA), mono unsaturated fatty acids (MUFA), Desaturase (16) index (DI 16) and hypocholesterolaemic/hypercholesterolaemic ratio (h/H). Increasing the Temperature-humidity index (THI) above 72, results in a decrease in the AI values and an increase in those of the PUFA/SFA. The values of health lipid indices showed a moderate positive correlation with those of THI (PUFA/SFA - 0.36) with rectal temperature (h/H, MUFA/SFA, UFA/SFA) rp from 0.36 to 0.37, and with respiratory rate (h/H, PUFA/SFA), rp of 0.33 and 0.31, respectively. Under the influence of heat stress, changes in the metabolic processes occur in the body of dairy cows leading to changes in the fatty acid content of milk related to the improvement of health lipid indices in terms of human health due to an increase in UFA and reduction in SFA.

Orthopterans (Insecta: Orthoptera) of conservation value in the Eurasian Eagle Owl Bubo bubo food in Bulgaria

Three species of Bush-crickets (Orthoptera) of conservation value or poorly known were found in the Eurasian Eagle Owl food in southeastern Bulgaria. Their localities are new country records and two of them cover Natura 2000 SCI zones. The repeated predation on Bradyporus macrogaster in UTM square MG99 confirms the potential of this area for a new Natura 2000 site.

AN ANALYSIS OF THE ECONOMIC DETERMINANTS AND THE QUALITY OF THE INSTITUTIONAL FRAMEWORK AS FACTORS TO ATTRACT FOREIGN DIRECT INVESTMENT IN SOUTHEASTERN EUROPE: THE CASE OF GREECE

Foreign Direct Investment (FDI) is considered by researchers as a critical factor for economic growth and development since they have shown a positive relationship between FDI and economic growth. The recent economic crisis in the European Union (EU) has brought up again the discussion of the key drivers specific to the attraction of FDI. In addition to strict economic factors the literature emphasizes the role of institutions in a country as determinants in attracting FDI inflows. An analysis of the role that the quality of institutions in attracting FDI has in Greece is attempted using an econometric model on institutional, regulatory, country specific and firm level data. For the purpose of giving a regional dimension in the analysis, and for attempting a comparison of the findings, the analysis focuses besides Greece, in two other Southeastern European countries (SEE), Bulgaria and Romania, being two new member states of the EU.

Resident European ground squirrels exhibit higher stress levels than translocated individuals after conservation reinforcement

The European ground squirrel (Spermophilus citellus) is a rodent inhabiting the open grasslands of central and southeastern Europe. The species is endangered, and various conservation activities are being conducted to preserve and improve the populations’ status, especially during the recent years including translocations of individuals. The success of these measures has varied and is potentially strongly influenced by the chronic and acute stress associated with the translocation process itself. This stress load, however, has rarely been investigated in the framework of such conservation projects, neither in translocated nor in resident individuals. To fill this gap, we investigated glucocorticoid metabolite concentrations in translocated ground squirrels and compared these with concentrations in resident animals of a reinforced colony in southeastern Bulgaria. Between 2017 and 2019, we sampled a total of 252 individuals for faecal cortisol metabolite concentrations (FCM). The results showed that FCM decreased after the release in translocated individuals and that the time span after the translocation event was the key variable explaining the decrease. Surprisingly, the FCM levels were higher in the resident ground squirrels than in the translocated individuals throughout the active season and in the following spring. Furthermore, we found no effect of FCM concentrations on dispersal distances or body mass gain in translocated individuals.

The natural history of the fallow deer, Dama dama (Linnaeus, 1758) in Bulgaria in prehistory and new evidence for the existence of an autochthonous Holocene population in the Balkans

AbstractThe fallow deer (Dama dama Linnaeus, 1758) has a long history of interaction with prehistoric humans. Beginning in the Neolithic, humans introduced fallow deer to several areas of the eastern Mediterranean and mainland Europe, with later additional importing happening in the Bronze and Iron Ages. However, in some parts of southeastern Europe, autochthonous populations of extant fallow deer may have survived through the end of the Pleistocene and into the early Holocene, making them available for exploitation by Neolithic and Chalcolithic communities. Climatic and vegetational regimes favourable to fallow deer covered nearly all of Bulgaria during this period; yet, the heavy use of the species by human communities was restricted to a very small area around southeastern Bulgaria. Eventually, climate deterioration, habitat change and overhunting led to the decline of fallow deer in later prehistory in Bulgaria. This paper offers a discussion of the environmental and cultural background of human‐fallow deer interactions from the sixth to fourth millennium BCE in Bulgaria. Using bivariate scatterplots and log ratio techniques, we demonstrate that Neolithic and Chalcolithic communities exploited a large extant fallow‐deer population, appearing to target both males and females equally. Our results are the first step in a larger archaeological investigation of human‐fallow deer relations that unfolded over several millennia, touching upon issues of settlement, migration and perhaps even taming or domestication.

ROSEN, BULGARIA: A NEWLY RECOGNIZED IRON OXIDE-COPPER-GOLD DISTRICT

AbstractThe Rosen copper veins in southeastern Bulgaria are recognized for the first time as an iron oxide-copper-gold (IOCG) district. The veins are located in the East Srednogorie segment of the Carpathian-Balkan calc-alkaline volcano-plutonic arc and were formed during an end-stage interval of extreme slab rollback and intra-arc rifting, which gave rise farther east to seafloor spreading in the Western Black Sea basin. The resulting submarine volcano-sedimentary rift basin is dominated by intermediate to mafic shoshonitic to ultrapotassic volcanism and subsidiary gabbro to syenite intrusion. The E- to NE-striking veins define a NW-striking alignment along the western contact of the syenite-dominated Rosen pluton, inferred to be part of a large ring dike. More than 40 veins, the most important formerly mined to depths as great as 1,000 m, contain an early, pegmatoidal, calcic-potassic assemblage followed by predominant magnetite (including the mushketovite variety), chlorite, and carbonates but also quartz, chalcopyrite, pyrite, and numerous other metallic minerals, which combine to give an unusual Fe-Cu-Au-Mo-Co-Ni-U-light rare earth element (LREE)-W-Bi-Zn-Pb geochemical signature. The close correlation between Fe, Cu, U, and LREEs is evident even in the flotation tailings. Vein molybdenite was dated during this study at 80.6 ± 0.4 Ma, which is similar to a U-Pb zircon age for monzosyenite from the Rosen pluton. The mineralogic and compositional features of the Rosen district are comparable to those of well-known IOCG deposits worldwide and geometrically similar to the vertically extensive IOCG veins in the Coastal Cordillera province of northern Chile. The subsidiary granitophile signature that accompanies the characteristic siderophile IOCG suite was also recognized recently at the giant Olympic Dam deposit in South Australia and elsewhere. Although no exposed intrusion is definitively implicated in the genesis of the Rosen veins, coexisting gabbro and syenite fluid sources may be hypothesized at depth in or beneath the coeval ring dike.

Two-Stage Late Jurassic to Early Cretaceous Hydrothermal Activity in the Sakar Unit of Southeastern Bulgaria

Southeastern Bulgaria is composed of a variety of rocks from pre-Variscan (ca. 0.3 Ga) to pre-Alpine sensu lato (ca. 0.15 Ga) time. The Sakar Unit in this region comprises a series of granitoids and gneisses formed or metamorphosed during these events. It is cut by a series of post-Variscan hydrothermal veins, yet lacks pervasive Alpine deformation. It thus represents a key unit for detecting potential tectonism associated with the enigmatic Cimmerian Orogenic episode, but limited geochronology has been undertaken on this unit. Here we report age constraints on hydrothermal activity in the Sakar Pluton. The investigated veins contain mainly albite–actinolite–chlorite–apatite–titanite–quartz–tourmaline–epidote and accessory minerals. The most common accessory minerals are rutile and molybdenite. Apatite and titanite from the same vein were dated by U–Pb LA–ICP-MS geochronology. These dates are interpreted as crystallization ages and are 149 ± 7 Ma on apatite and 114 ± 1 Ma on titanite, respectively. These crystallization ages are the first to document two stages of hydrothermal activity during the late Jurassic to early Cretaceous, using U–Pb geochronology, and its association with the Cimmerian orogenesis. The Cimmerian tectono-thermal episode is well-documented further to the east in the Eastern Strandja Massif granitoids. However, these are the first documented ages from the western parts of the Strandja Massif, in the Sakar Unit. These ages also temporally overlap with previously published Ar–Ar and K–Ar cooling ages, and firmly establish that the Cimmerian orogeny in the studied area included both tectonic and hydrothermal activity. Such hydrothermal activity likely accounted for the intense albitization found in the Sakar Unit.

Variability, heritability, and correlations among grain yield and related traits in hulless barley accessions

The aim of the present study was to investigate the variability, heritability and correlation between grain yield and yield-related traits of hulless accessions of spring barley under Southeast Bulgarian conditions. The research work was conducted in the experimental field of the Institute of Agriculture - Karnobat, South-eastern Bulgaria during the 2016 and 2017 growing seasons. The trail consisted of 20 six-rowed hulless barley accessions from ICARDA. A significant variation of grain yield and yield-related traits among the studied hulless barley accessions was found. The values of broad-sense heritability were from 1.81% for grain yield to 81.84% for the number of spikelets per spike. The number of spikes per plant had a direct positive effect on grain yield of hulless spring barley in both growing seasons. In a condition of water stress (the second year of study), the weight of grains per spike shows the highest direct effect on grain yield. Since the number of spikes per plant and weight of grains per spike had low heritability, these traits can be used as additional traits for selection for improving grain yield in the hulless barley breeding program of hulless barley only if the selection be practiced in later generations in replicated trials.