Shtereva L.,Bulgarian Academy of Science |
Stoimenova E.,Bulgarian Academy of Science |
Drumeva-Yoncheva M.,Tobacco and Tobacco Products Institute |
Michailova B.,Bulgarian Academy of Science |
And 2 more authors.
Archives of Biological Sciences | Year: 2017
The effect of prolonged water deficit on four Virginia (flue-cured) tobacco genotypes, Line 842, Oxford 207, RG11 and Virgin D, was analyzed in whole plants. Drought stress was induced by withholding irrigation and subjecting plants to low, moderate and severe regimes. Some growth indices such as fresh weight, plant growth rate, number, color and area of new developed leaves, as well as proline, hydrogen peroxide (H2O2) and malondialdehyde (MDA) content as a measure of oxidative stress were investigated to examine the role of genotype in water-deficit tolerance. Under stress, the weight of the aboveground parts of plants, plant growth height, number of new developed leaves and leaf area index decreased with the severity of treatment. The stressed plants accumulated more proline, malonildialdehide and hydrogen peroxide than control non-stressed plants under water-deficit conditions. The results showed that among the genotypes, Virgin D (VD) was the most sensitive to drought, while L 842 and Oxford 207 were moderately tolerant; RG11 was drought-tolerant. This suggests that the correlation between the physiological traits and level of antioxidative response exists and therefore it could be used as a rapid screening test to evaluate the drought tolerance of tobacco. © 2017 by the Serbian Biological Society.
Dimanov D.,Tobacco and Tobacco Products Institute |
Masheva V.,Tobacco and Tobacco Products Institute |
Dimitrova D.,Plant Genetic Resources Institute K Malkov
Bulgarian Journal of Agricultural Science | Year: 2013
It has been researched the possibility for in vitro N. tabacum sp., S. tuberosum sp., S. lycopersicum sp. Cultivars at a different nutritive mediums. A positive effect of liquid nutrient media on micropropagation in vitro in three Solanaceae species, compared to solid agar medium was established. The best for micropropagation in vitro in the varieties of three species - N. tabacum, S. tuberosum and S. lycopersicum is nutritive medium B. The importance of genotypein the reproduction in vitro has been demonstrated. The unified systeme for micropropagation in vitro - based on nutritive medium B of varieties of three family Solanaceae species was created.
Hristeva T.,Tobacco and Tobacco Products Institute |
Yanev M.,Agricultural University of Plovdiv |
Bozukov H.,Tobacco and Tobacco Products Institute |
Kalinova S.,Agricultural University of Plovdiv
Bulgarian Journal of Agricultural Science | Year: 2015
In the process of tobacco growing, during field tests, scientists studied the impact of chloroacetamide herbicides Butizan S (a.s. metazachlore) and Dual Gold 960 EK (a.s. S-metolachlor) on soil microbial communities. They determined dynamically the population density of trophic groups of microorganisms, which are indicators for the general sanitary condition of the soil. A suppression in the numerical development of ammonifying and immobilizing mineral nitrogen microorganisms was found. This was achieved without disturbing the mineral nutrition of tobacco plants. An increase was recorded in the spores and in the relative proportion of spore-like microorganisms, which indicates degraded life conditions in the soil. Metolachlor has a negative impact with a longer duration. The likely period of adaptation in microbial communities after treatment is about 15 days for Butizan S (a.s. metazachlore) and 35 days for Dual Gold 960 EK (a.s. S-metolachlor). The stimulation effect on the group of Actinomycetes and the changes in their dynamics defines them as the first biodegrading agents in both herbicides, followed by the ammonifying microorganisms. © 2015, National Centre for Agrarian Sciences. All Rights Reserved.
Nikolov N.,Agricultural University of Plovdiv |
Bozhinova R.,Tobacco and Tobacco Products Institute |
Hristeva T.S.,Tobacco and Tobacco Products Institute
Journal of Environmental Protection and Ecology | Year: 2016
The influence of Black Sea organic-mineral sediments (sapropels) was studied on the soil properties and accumulation of Pb, Cd, Zn and Cu in tobacco plants cv. Krumovgrad 988 (oriental) and cv. Burley 1000 in pot experiment set on a Cinnamonic pseudopodzolic forest soil (Planosol). Mature leaves from different stalk position - lower, middle and upper were analysed. Introduced at an amount 30 g/kg sapropels neutralise the soil acidity from 4.9 to 7.53 units, increase the humus content from 1.97 to 2.38% and decreased the accumulation of Pb in tobacco leaves from 34.8 to 100%; Cd - from 64.3 to 90.9%; Zn - from 15.5 to 63.7%, and Cu - from 42.7 to 81.2%.
Hristov Hr.,Plovdiv University |
Balabanov N.,Plovdiv University |
Marinova S.,Plovdiv University |
Zaprianova P.,Tobacco and Tobacco Products Institute |
And 5 more authors.
AIP Conference Proceedings | Year: 2010
The report presents the results from research of contents of U and Th in soil samples from the region of the Belene Nuclear Power Plant (NPP). The report presents the investigations for sorption of U in the system soil-water from region. The report presents similarly the results for the natural radiation background - about 0,14 μSv/h, for the investigated region. © 2009 American Institute of Physics.
Bozhinova R.,Tobacco and Tobacco Products Institute
Bulgarian Journal of Agricultural Science | Year: 2016
The effects of the different phosphorus rates (0; 75 and 225 kg ha-1) on heavy metal concentrations in soil and tobacco plants have been studied in a stationary field trial. A long-term fertilizer experiment with continuous tobacco cropping system was established on rendzina soil (Rendzic Leptosols) in 1966. Although P fertilizers are considered a source of anthropogenic contamination of soil, the application of increasing P rates did not increase the total Cd, Pb and Cu content in the soil. Slightly higher Ni concentration was observed in plots receiving supplemental P fertilizer as compared to 0 kg P2O5 ha-1 treatment. The changes in the available Cd and Pb content as a result from the long-term P fertilization are insignificant. There was significant increase of available Ni and Cu in the plots treated with 225 kg P2O5 ha-1 compared to the 0 kg P2O5 ha-1 treatment. Increasing levels of P fertilization had no pronounced effect on Cd, Pb and Ni concentrations in leaves. Copper content in leaves decreased with the increase of P fertilizing levels. Therefore, the impact of phosphate fertilizer application on Cd, Pb, Ni and Cu content in soils and tobacco plants was proved to be limited. Under our experimental conditions, the risk of heavy metals’ accumulation in soil and tobacco associated with long-term P fertilization was low. © 2016, National Centre for Agrarian Sciences. All rights reserved.
Dagnon S.,Plovdiv University |
Stoilova A.,Tobacco and Tobacco Products Institute |
Ivanov I.,Plovdiv University |
Nikolova S.,Plovdiv University
Beitrage zur Tabakforschung International/ Contributions to Tobacco Research | Year: 2010
The influence of cigarette design on the content of phenols in mainstream tobacco smoke was studied. The most abundant phenols - catechol, hydroquinone, phenol, o-, m- and p-cresol, and resorcinol - were determined by HPLC with fluorescence detection. Hydroquinone and catechol made the most significant contribution to the total content of phenols with maximum values of 135.0 μg/cig and 95.7 μg/cig, respectively. The highest total content of phenols (330.9 μg/cig) was measured in the smoke of a Virginia tobacco cigarette. The total content of phenols (μg/cig) in cigarette mainstream smoke decreased linearly with increased filter ventilation, R2 = 0.9536. The results obtained indicate that filtration and ventilation can strongly influence the mainstream tobacco smoke content of phenol and its less polar derivatives, o-, m- and p-cresol, which were reduced by up to 85%. Hydroquinone and catechol are less affected and only cigarettes with the special "recessed charcoal filter system" and cigarettes with filter ventilation over 50% showed significant reductions. On a per mg 'tar' basis the largest contributor to phenols in cigarette mainstream smoke was the selection of the tobacco type. The use of any standard commercial filter on an unfiltered cigarette can substantially reduce the yield of phenols in cigarette mainstream smoke. The use of special filters (e.g., the "recessed charcoal filter system") or high levels of cigarette ventilation does not reduce the amount of phenols in tobacco smoke considerably when normalized on a per mg 'tar' basis.
Hristeva T.,Tobacco and Tobacco Products Institute |
Dekalska T.,Tobacco and Tobacco Products Institute |
Denev I.,Plovdiv University
Biotechnology and Biotechnological Equipment | Year: 2013
Broomrapes are obligate root parasites from the family Orobanchaceae. Several of them parasitize important crops and have major economical impact. Important features of broomrapes are their great adaptability and flexibility, which hampers the understanding of the factors affecting the host-parasite system. The role of the soil microorganisms as a biotic factor in this system is not well understood yet. A number of recent studies demonstrated that parasitic weeds use a signaling mechanism between host plants and symbiotic arbuscular microbes to establish parasitic associations. Formation of arbuscular mycorrhizal (AM) associations however, significantly suppresses seed germination of parasitic weeds. The aim of this study was to determine whether the established host-parasite associations can also influence the major trophic groups of soil microorganisms in the rhizosphere. The study was conducted on 11 host plant-parasite systems with nine broomrape species. For comparison, similar non-infected host plants were used. The quantities of the autochthonous and oligotrophic microorganisms, streptomycetes, soil fungi, ammonifying microorganisms, assimilating mineral (NH4 +) nitrogen and aerobic nitrogen-fixing bacteria of the genus Azotobacter were determined. Microbiological indexes, characterizing the structure of microbial communities were determined. The population density of all microbial communities formed in the presence of broomrapes was considerably decreased, threeto five-fold. Regardless of the exact numbers, in all involved host-parasite systems the trend remained the same. These findings demonstrated that not only can arbuscular flora suppress parasitic weeds, but also, when host-parasitic associations have already been established, parasitic weeds can suppress and influence the level of biodiversity in major trophic groups of soil microorganisms in the rhizosphere. The statistical analysis demonstrated that the observed changes are an adaptive response of the microbial communities precisely to the presence of broomrape. The research in this area should at a next step further characterize the specifics of the host-parasite-AM interactions at different stages of the broomrape life cycle. © Biotechnol. & Biotechnol. Eq.
Docheva M.,Tobacco and Tobacco Products Institute |
Dagnon S.,Plovdiv University |
Statkova-Abeghe S.,Plovdiv University
Natural Product Research | Year: 2014
The flavonoid-rich natural products exert a wide range of pharmacological properties. This investigation aimed at obtaining extracts from tobacco cultivars and waste enriched with flavonoids and purified from nicotine and phenolic acids, and evaluating their radical scavenging potential. Extraction with a mixture of ethyl acetate-methanol (1:1, v/v) was employed resulting in 100% yield for flavonoids and 36% yield for phenolic acids. The crude extracts were purified using preparative column chromatography on silica gel. The content of flavonoids in the purified extracts varied from 8.8 ± 1.1% to 14.3 ± 1.8%. Nicotine was not detected in amounts higher than 0.3 g mL-1. The content of phenolic acids was lower than 1.0%. The radical scavenging potential of extracts from tobacco cultivars exhibited values from IC50 = 35.0 ± 3.1 to 64.6 ± 7.5 g mL-1. The extracts obtained by the proposed procedure are enriched with flavonoids with high radical scavenging potential and are purified from nicotine and phenolic acids. They can be regarded as potential biopharmaceuticals. © 2014 Taylor & Francis.
Ivanov K.,Plovdiv University |
Zaprjanova P.,Tobacco and Tobacco Products Institute |
Petkova M.,Plovdiv University |
Stefanova V.,Plovdiv University |
And 3 more authors.
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2012
The most widely used method for determination of total phosphorus in soils is perchloric acid digestion, followed by a colorimetric assay to measure the concentration of P in solution. The first part of this study compares an alternative digestion method, using aqua regia (ISO 11466 and EPA Method 3052), with perchloric acid digestion procedure, and also compares inductively coupled plasma mass spectroscopy (ICP-MS) with colorimetry for the measurement of P on the basis of five internationally certified standard soils and 20 real-life soils with widely different extractability of phosphorus. The phosphorus concentration was determined by means of the reduced phosphomolybdenum blue and ICP-MS. The relationship between methods has been examined statistically. Good agreement of the results from colorimetry and ICP-MS was established for all certified soils. The microwave-assisted digestion with aqua regia was comparable, both in precision and accuracy, with the hot plate aqua regia method. The phosphorus concentration found with the HF + HClO 4 digestion method was in good agreement with the certified mean values, while the superiority in extracting phosphorus, when compared to other methods, was obvious. Soil testing for plant-available phosphorus in Bulgaria and many European countries is most commonly conducted using acid Ca-lactate extraction (Egner-Riehm test) and alkaline sodium bicarbonate extraction (BDS ISO 11263:2002), based on Olsen test, followed by a colorimetric assay to measure the concentration of P in solution. The second part of this study reports the differences between Egner-Riehm test and BDS ISO 11263:2002 measured colorimetrically and by ICP-MS. Fifty soils were selected from South Bulgaria to represent a wide range of soil properties. It was established that ICP-MS consistently yielded significantly higher P concentrations than the colorimetric method in both extraction tests, and the relative differences were greatest in soils with lower P concentrations. © 2012 Elsevier B.V.