The quick decrease of organic matter is a direct result of the sharp reduction of the biomass ent... more The quick decrease of organic matter is a direct result of the sharp reduction of the biomass entering into the soil and quick mineralization of the organic matter in consequence of soil aeration after plowing. The rate of organic matter mineralization decreases till creation of an equilibrium state between the main processes – synthesis – decomposition. The infl uence of farming production and plant output on the content of labile forms and the need for plant residues to conserve and increase soil fertility of alluvial meadow soil (Eutric sandy and loamy), calcareous (Calcic chernozems (CHcc), leached chernozem (Haplic chernozems (Chha) and pseudopodzolic soil (Planosols (PL) cropped with wheat, maize and lucerne was studied in the 2000-2004 period in the Institute of Forage Crops. The obtained results were compared with those of virgin analogues of these soils. There is a marked tendency to increase of plant residues by 50-80 % in all soils at both depths and detritus content by 4...
Soil erosion can be considered, with different level of severity, an EU–wide problem. Erosion is ... more Soil erosion can be considered, with different level of severity, an EU–wide problem. Erosion is a natural geological phenomenon resulting from the removal of soil particles by water or wind, transporting them elsewhere. However some human activities can dramatically increase erosion rates. Soil organic matter assures the binding and buffering capacity of the soil, an essential determinant of erosion resistance and soil fertility. Crops grown without tillage, use water more efficiently, the water–holding capacity of the soil increases, and water losses from runoff and evaporation are reduced. In addition, soil organic matter and populations of beneficial insects are maintained, soil and nutrients are less likely to be lost from the field and less time and labour is required to prepare the field for planting. Greater water–stability of surface soil aggregates, higher microbial activity and earthworm populations and higher total carbon can be found In eneral, the greatest advantages o...
Global Journal of Environmental Science and Management, 2015
Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertili... more Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i) for fertilization as follows: N0P0K0 (control); N60P100K80 (an accepted technology); N23P100K35 (nitrogen was applied 1/2 in first year of growing and 1/2 in third year); N23P100K35 (nitrogen was supplied pre-sowing); N35P80K50, and Аmophose - 250 kg/ha, calculated at fertilizing rates N27P120K0; ii) for soil cultivation as follows: soil loosing 10-12 cm, plough at depth 12-15 cm, 22-24 cm (an accepted technology), 18-22 cm and 30-35 cm. It was found that soil cultivation and mineral fertilization had effect on nitrogen use efficiency and life cycle of root nodules in Alfalfa. Nitrogen use efficiency was found to be highest at N23P100K35 and plough at the depth of 22-24 cm....
РЕЗЮМЕ SUMMARY В статията са отразени резулта-тите от три годишни проучвания за устойчивостта на ... more РЕЗЮМЕ SUMMARY В статията са отразени резулта-тите от три годишни проучвания за устойчивостта на ниски зимни температури при полски условия на основните за страната винени сортове лози, отглеждани в района на Северна България. С най-ниска степен на устой-чивост през годините на проучване са сортовете Мерло, Мискет врачански, Рубин и Шардоне, при които процента на загивалите главни и заместващи пъпки в зимните очи е най-висок. С по-висока степен на устойчивост са сорто-вете получени по метода на междуви-довата хибридизация-Сторгозия и Мискет кайлъшки. При тях процента на загиналите главни и заместващи пъпки е значително по-нисък. Ключови думи: лозя, винени сортове лози, устойчивост, главни пъпки, заместващи пъпки, ниски зимни температури The paper presents the results of a three-year study on the low winter temperatures resistance under field conditions of the main for the country wine grapevine varieties grown in the region of Northern Bulgaria. The lowest degree of resistance durin...
Summary: Field pea attained greater importance as a cultivated plant in Bulgaria at the beginning... more Summary: Field pea attained greater importance as a cultivated plant in Bulgaria at the beginning of the 20th century. Until 1964, only breeding for forage was in use, with developed winter varieties №5 and Pleven 2. Recently, fi eld pea achieved the greatest increase (283.3%) in the sown areas, since the variety structure was updated annually. There are 10 registered varieties in total, with 7 spring and 3 winter ones. The composition of the Bulgarian Pisum collections is highly variable, with accessions of diverse status. The greatest effi ciency is obtained in a combination of bulk method in the early generations and certain features of pedigree, single seed method, with possible modifi cations and inclusion of the mutational variability.
ILIEVA, A,. I. PACHEV and T. KERTIKOV, 2007. Influence of different soil cultivation and fertiliz... more ILIEVA, A,. I. PACHEV and T. KERTIKOV, 2007. Influence of different soil cultivation and fertilizing on the content of plastid pigments and nitrate reductase activity in lucerne for forage. Bulg. J. Agric. Sci., 13: 45-50 In a field trial carried out in the Second experimental field of the Institute of Forage Crops in Pleven the influence of mineral fertilizing (N6P10K8, N2.3P10K3.5, N3.5P8K5.0 and Amophos) and different soil cultivations (12-15 cm loosening and ploughing at 12-15 cm, 22-24 cm, 18-22 cm, 3035 cm) on the nitrate reductase activity (NR) and content of plastid pigments was studied. It was found that the NR activity in leaves exceeded 4 to 8 times the activity in stems and roots of lucerne. The different rates of mineral fertilizing and soil cultivation exerted a different influence on the NR activity and total content of plastid pigments. The application of N6P10K8 by approved technology increased the NR activity and total content of plastid pigments to the greatest de...
Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertili... more Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i) for fertilization as follows: N0P0K0 (control); N60P100K80 (an accepted technology); N23P100K35 (nitrogen was applied 1/2 in first year of growing and 1/2 in third year); N23P100K35 (nitrogen was supplied pre-sowing); N35P80K50, and Amophose - 250 kg/ha, calculated at fertilizing rates N27P120K0; ii) for soil cultivation as follows: soil loosing 10-12 cm, plough at depth 12-15 cm, 22-24 cm (an accepted technology), 18-22 cm and 30-35 cm. It was found that soil cultivation and mineral fertilization had effect on nitrogen use efficiency and life cycle of root nodules in Alfalfa. Nitrogen use efficiency was found to be highest at N23P100K35 and plough at the depth of 22-24 cm....
The study of plant - microbial associations is important for the development of modern farming an... more The study of plant - microbial associations is important for the development of modern farming and environmental ecology. In the process of the gradual reduction of import quantities of mineral fertilizers and pesticides to increase the plants productivity and yield it is necessary to activate the agrocenoses biological components, where learning about the legume bean - rizobial symbiosis nitrogen - fixation, mobilization and provision of the plants with environmentally safe biological nitrogen ant its storage in the soil are the reasons for constant researches and experiments. The purpose of this study is to determine the influence of the period of sowing on the development of the root mass, tuber -formation, the amount of post - harvest residues and soil agrochemical composition of winter fodder peas. the experiment is made in the period of 2005 to 2008 in Pleven EFC with the method of random block system. The result show that in the first sampling maximum number of tubers (26.62 g plant) and root dry weight (1.55 g/plant) were formed in a second sowing period (10-15 October), but with the greatest amount of post - harvest residues (435.5 kg/ha) are those of the a third period (25 - 30 October). After the harvest and the secondary growing of peats the indicators value are lower by 76,2, 30.2 and 61.6%. The agrochemical soil analysis shows pronounced trends in mineral nitrogen and organic carbon content under the influence of different sowing periods. The soils where the plants are harvested from later sowing time are characterized with high nitrogen and carbon content determined by the larger root volume and post - harvest residues in these terms. After the pea harvest the current and potential soil acidity values decreased by 2.7 and 5.5 percent compared with the control variant.
The quick decrease of organic matter is a direct result of the sharp reduction of the biomass ent... more The quick decrease of organic matter is a direct result of the sharp reduction of the biomass entering into the soil and quick mineralization of the organic matter in consequence of soil aeration after plowing. The rate of organic matter mineralization decreases till creation of an equilibrium state between the main processes - synthesis - decomposition. The infl uence of farming production and plant output on the content of labile forms and the need for plant residues to conserve and increase soil fertility of alluvial meadow soil (Eutric sandy and loamy), calcareous (Calcic chernozems (CHcc), leached chernozem (Haplic chernozems (Chha) and pseudopodzolic soil (Planosols (PL) cropped with wheat, maize and lucerne was studied in the 2000-2004 period in the Institute of Forage Crops. The obtained results were compared with those of virgin analogues of these soils. There is a marked tendency to increase of plant residues by 50-80% in all soils at both depths and detritus content by 40...
The quick decrease of organic matter is a direct result of the sharp reduction of the biomass ent... more The quick decrease of organic matter is a direct result of the sharp reduction of the biomass entering into the soil and quick mineralization of the organic matter in consequence of soil aeration after plowing. The rate of organic matter mineralization decreases till creation of an equilibrium state between the main processes – synthesis – decomposition. The infl uence of farming production and plant output on the content of labile forms and the need for plant residues to conserve and increase soil fertility of alluvial meadow soil (Eutric sandy and loamy), calcareous (Calcic chernozems (CHcc), leached chernozem (Haplic chernozems (Chha) and pseudopodzolic soil (Planosols (PL) cropped with wheat, maize and lucerne was studied in the 2000-2004 period in the Institute of Forage Crops. The obtained results were compared with those of virgin analogues of these soils. There is a marked tendency to increase of plant residues by 50-80 % in all soils at both depths and detritus content by 4...
Soil erosion can be considered, with different level of severity, an EU–wide problem. Erosion is ... more Soil erosion can be considered, with different level of severity, an EU–wide problem. Erosion is a natural geological phenomenon resulting from the removal of soil particles by water or wind, transporting them elsewhere. However some human activities can dramatically increase erosion rates. Soil organic matter assures the binding and buffering capacity of the soil, an essential determinant of erosion resistance and soil fertility. Crops grown without tillage, use water more efficiently, the water–holding capacity of the soil increases, and water losses from runoff and evaporation are reduced. In addition, soil organic matter and populations of beneficial insects are maintained, soil and nutrients are less likely to be lost from the field and less time and labour is required to prepare the field for planting. Greater water–stability of surface soil aggregates, higher microbial activity and earthworm populations and higher total carbon can be found In eneral, the greatest advantages o...
Global Journal of Environmental Science and Management, 2015
Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertili... more Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i) for fertilization as follows: N0P0K0 (control); N60P100K80 (an accepted technology); N23P100K35 (nitrogen was applied 1/2 in first year of growing and 1/2 in third year); N23P100K35 (nitrogen was supplied pre-sowing); N35P80K50, and Аmophose - 250 kg/ha, calculated at fertilizing rates N27P120K0; ii) for soil cultivation as follows: soil loosing 10-12 cm, plough at depth 12-15 cm, 22-24 cm (an accepted technology), 18-22 cm and 30-35 cm. It was found that soil cultivation and mineral fertilization had effect on nitrogen use efficiency and life cycle of root nodules in Alfalfa. Nitrogen use efficiency was found to be highest at N23P100K35 and plough at the depth of 22-24 cm....
РЕЗЮМЕ SUMMARY В статията са отразени резулта-тите от три годишни проучвания за устойчивостта на ... more РЕЗЮМЕ SUMMARY В статията са отразени резулта-тите от три годишни проучвания за устойчивостта на ниски зимни температури при полски условия на основните за страната винени сортове лози, отглеждани в района на Северна България. С най-ниска степен на устой-чивост през годините на проучване са сортовете Мерло, Мискет врачански, Рубин и Шардоне, при които процента на загивалите главни и заместващи пъпки в зимните очи е най-висок. С по-висока степен на устойчивост са сорто-вете получени по метода на междуви-довата хибридизация-Сторгозия и Мискет кайлъшки. При тях процента на загиналите главни и заместващи пъпки е значително по-нисък. Ключови думи: лозя, винени сортове лози, устойчивост, главни пъпки, заместващи пъпки, ниски зимни температури The paper presents the results of a three-year study on the low winter temperatures resistance under field conditions of the main for the country wine grapevine varieties grown in the region of Northern Bulgaria. The lowest degree of resistance durin...
Summary: Field pea attained greater importance as a cultivated plant in Bulgaria at the beginning... more Summary: Field pea attained greater importance as a cultivated plant in Bulgaria at the beginning of the 20th century. Until 1964, only breeding for forage was in use, with developed winter varieties №5 and Pleven 2. Recently, fi eld pea achieved the greatest increase (283.3%) in the sown areas, since the variety structure was updated annually. There are 10 registered varieties in total, with 7 spring and 3 winter ones. The composition of the Bulgarian Pisum collections is highly variable, with accessions of diverse status. The greatest effi ciency is obtained in a combination of bulk method in the early generations and certain features of pedigree, single seed method, with possible modifi cations and inclusion of the mutational variability.
ILIEVA, A,. I. PACHEV and T. KERTIKOV, 2007. Influence of different soil cultivation and fertiliz... more ILIEVA, A,. I. PACHEV and T. KERTIKOV, 2007. Influence of different soil cultivation and fertilizing on the content of plastid pigments and nitrate reductase activity in lucerne for forage. Bulg. J. Agric. Sci., 13: 45-50 In a field trial carried out in the Second experimental field of the Institute of Forage Crops in Pleven the influence of mineral fertilizing (N6P10K8, N2.3P10K3.5, N3.5P8K5.0 and Amophos) and different soil cultivations (12-15 cm loosening and ploughing at 12-15 cm, 22-24 cm, 18-22 cm, 3035 cm) on the nitrate reductase activity (NR) and content of plastid pigments was studied. It was found that the NR activity in leaves exceeded 4 to 8 times the activity in stems and roots of lucerne. The different rates of mineral fertilizing and soil cultivation exerted a different influence on the NR activity and total content of plastid pigments. The application of N6P10K8 by approved technology increased the NR activity and total content of plastid pigments to the greatest de...
Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertili... more Nitrogen use efficiency and life cycle of root nodules in alfalfa after different mineral fertilization and soil cultivation practices were studied. Field trial was conducted in the Institute of Forage Crops, Pleven, Bulgaria on leached chernozem subsoil type and no irrigation. The next treatments were tested: i) for fertilization as follows: N0P0K0 (control); N60P100K80 (an accepted technology); N23P100K35 (nitrogen was applied 1/2 in first year of growing and 1/2 in third year); N23P100K35 (nitrogen was supplied pre-sowing); N35P80K50, and Amophose - 250 kg/ha, calculated at fertilizing rates N27P120K0; ii) for soil cultivation as follows: soil loosing 10-12 cm, plough at depth 12-15 cm, 22-24 cm (an accepted technology), 18-22 cm and 30-35 cm. It was found that soil cultivation and mineral fertilization had effect on nitrogen use efficiency and life cycle of root nodules in Alfalfa. Nitrogen use efficiency was found to be highest at N23P100K35 and plough at the depth of 22-24 cm....
The study of plant - microbial associations is important for the development of modern farming an... more The study of plant - microbial associations is important for the development of modern farming and environmental ecology. In the process of the gradual reduction of import quantities of mineral fertilizers and pesticides to increase the plants productivity and yield it is necessary to activate the agrocenoses biological components, where learning about the legume bean - rizobial symbiosis nitrogen - fixation, mobilization and provision of the plants with environmentally safe biological nitrogen ant its storage in the soil are the reasons for constant researches and experiments. The purpose of this study is to determine the influence of the period of sowing on the development of the root mass, tuber -formation, the amount of post - harvest residues and soil agrochemical composition of winter fodder peas. the experiment is made in the period of 2005 to 2008 in Pleven EFC with the method of random block system. The result show that in the first sampling maximum number of tubers (26.62 g plant) and root dry weight (1.55 g/plant) were formed in a second sowing period (10-15 October), but with the greatest amount of post - harvest residues (435.5 kg/ha) are those of the a third period (25 - 30 October). After the harvest and the secondary growing of peats the indicators value are lower by 76,2, 30.2 and 61.6%. The agrochemical soil analysis shows pronounced trends in mineral nitrogen and organic carbon content under the influence of different sowing periods. The soils where the plants are harvested from later sowing time are characterized with high nitrogen and carbon content determined by the larger root volume and post - harvest residues in these terms. After the pea harvest the current and potential soil acidity values decreased by 2.7 and 5.5 percent compared with the control variant.
The quick decrease of organic matter is a direct result of the sharp reduction of the biomass ent... more The quick decrease of organic matter is a direct result of the sharp reduction of the biomass entering into the soil and quick mineralization of the organic matter in consequence of soil aeration after plowing. The rate of organic matter mineralization decreases till creation of an equilibrium state between the main processes - synthesis - decomposition. The infl uence of farming production and plant output on the content of labile forms and the need for plant residues to conserve and increase soil fertility of alluvial meadow soil (Eutric sandy and loamy), calcareous (Calcic chernozems (CHcc), leached chernozem (Haplic chernozems (Chha) and pseudopodzolic soil (Planosols (PL) cropped with wheat, maize and lucerne was studied in the 2000-2004 period in the Institute of Forage Crops. The obtained results were compared with those of virgin analogues of these soils. There is a marked tendency to increase of plant residues by 50-80% in all soils at both depths and detritus content by 40...
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