Plants Root Interference Area, A Benefit To The Microbial Community

Part of byproducts synthesized by plants through photosynthesis reach the ground, where create selective microenvironments for micro-flora and associations of plant - micro-organisms, which are a benefit for plant growth Setting the interference effect of the root interference area of vines and herbaceous plants and of radicular exudates from vine rhizosphere on microbial community and estimating microbial population present on the vine leaves. The biological material was represented by leaves (Fa, Fb), and soil rhizosphere (Ra, Rb) of two varieties of vines (Tamaioasa Romanian white and black / TA, TN), and from the vine roots interference area with other herbaceous plants (Ma, Mb). The soil has never been chemically treated. The microbiological study of biological samples was performed by classical and molecular methods. Overall, bacteria had a significant presence in soil samples taken from the root interference zone (Ma, Mb). Actinomycetes quantitatively dominated the root interference area  of herbaceous plant with variety TA. The range of actinomycetes species and leaves microflora was reduced. In this study we have shown that significant growth of microorganisms occurs in the interference area of vine with other herbal plants as a result of the cumulative effect of radicular exudates

Evaluation of bacterial community and of actinomycetes composition from the Allium ursinum L. species rhizosphere

Soil s microbiota is an effective recycling instrument of organic matter, of nutritional resources providance for living organisms, an instrument of atmospheric nitrogen fixation in forests biomes. This one changes under the action of some abiotic and biotic factors. In this research, we have studied the impact of the plant of Allium ursinum L, the soil moisture and the way to prepare the soil in the laboratory condition, upon bacterial community and the composition of actinomycetes from the Streptomyces genus, from the forest soil. The soil studied belongs to a deciduous forest, located in the western part of the country. The soil s samples have been taken from the top layer of the soil (0-20 cm), from the Allium ursinum L. plants rhizosphere, plants which have been in their blossoming period. The microbian groups of interest have been isolated in specific environments resulted from soil s samples prepared beforehand by plants residue removal (SC) and sifting, as well as from original soil s samples which had no prior preparation (SN). The results show that the bacteria in the soil sample SC compared to the bacteria in the soil sample SN has dominated numerically. The bacterian species which predominated in both types of soil was Bacillus cereus var. mucoydes. The actinomycetes have been equal numerically in both soil’ samples mentioned below, but their diversity has been reduced. The highest number of species belonging to the genus of Streptomyces was isolated from soil sample SC. The species of actinomycetes, common for both soil samples were: S. albosporeus and S. albus. In the soil sample SC, S. albosporeus species dominanted, and in the soil sample SN, S.chromogenes was the most representative

Statistical evaluation of heavy metal content in some capsicum varieties available on the Romanian market

The aim of this study is to emphasis the heavy metals content in seven capsicum varieties of capsicum of the specie Capsicum annuum L., available on the Romanian market. From the analyzed Capsicum fruit samples, three Capsicum assortments were cultivated in Romania and the other four were imported from Italy and Turkey. The studied heavy metals (copper, zinc, manganese, iron, cobalt, lead, nickel, cadmium and chromium) have normal concentration values that are not of any risk to human health. Cadmium is not detectable in all studied samples. The heavy metal content associated with statistical analysis programs permits the identification of characteristics specific to the origin of products and the graphical chemical fingerprint of the studied capsicum species. The chemical fingerprinting of a plant demands the determination of a large number of elements (DJINGOVA ET AL., 2004). The study is revealing similar distribution pattern

Changes in the structure of actinomycete populations in the rhizosphere of vicia sativa species

It is a known fact that species of legumes improve the soil they are grown on, but at the same time, they produce the so-called rhizosphere effect or rhizodeposit that has a selective effect on the microorganisms which are considered "fertility effectors" for soil. From the three studied area the highest number of actinomycetes was found in edaphosphere and the lowest number in the area influenced by roots. Among the few factors under research for the purpose of this paper, humus and potassium were observed to have the strongest impact on this group. Humidity is a factor that could change the competition between soil microorganisms and plants in the soil for N and it could affect the stability of aggregates

Vegetables, fruits, honey and pollen, a natural source of zinc

This work aimed to evaluate zinc content in six common vegetables (parsley, carrot, dill, onion, cucumber and beans), three common fruits (apples, raspberry and dog rose), bees honey and pollen. Determination of zinc content in soil, raw vegetables and fruits, as well as in bees honey and pollen from local apiaries were carried out by FAAS. All experiments and analyses were performed in triplicate. Overall, the highest zinc concentration was found in the leaves (carrot 48.07 mg kg-1, parsley 46.62 mg kg-1, dog rose leaves 36.13 mg kg-1) and beans crops (41.26 mg kg-1). According to our study the highest content occurs in the plants of the Apiaceae Family and in Rosa canina leaves

The variation of actinobacteria species from a vicia sativa cultivated soil microhabitat

Actinobacteria is a fairly complex group, intermediate between bacteria and filamentous fungi involved in producing some infection, in the case of pathogenic strains and recycling of organic matter, as in the case of nonpathogenic actinobacteria. Literature data have surprised many plant-microorganism interaction, on the one hand making reference to the mineralization processes involving microorganisms by whom plants necessary nutrients are released, and on the other hand underlines the influence of plants on the quantity and quality of microbial population in root area as a result of exudates removed in the natural environment. Actinobacteria from Frankia genus are counted among bacteria being able to fix nitrogen, and those from the genus Streptomyces are major producers of antibiotics and numerous secondary metabolites. This paper presents the study of the composition of Streptomyces genus actinobacteria community from a moderately gleyed eutricambosoil, grown with vetch (Vicia sativa). The soil is located in the western part of Romania. Biological material sampling was conducted in October, the depth of 0-20 cm. Isolation and studies of this bacterial group were performed "in vitro", on Gause 1 culture media. Actinobacteria were collected from four areas (biotopes): the plot uncultivated with Vicia sativa (control variant), the far rhizospheric area, the hairy root and root areas of vetch plant. Based on effectuated observations, it was noticed that soil microhabitats contain a variety of actinobacteria and S. albosporeus, S. aureus, S. griseus, S.albus, S. nigrescens, S. lavenduleroseus, S. helvolus. Numerically dominant species in tested soil samples are: S. griseus, S. albus and S. albosporeus

Graphical chemical fingerprints of parsley, dill and lovage leaves

The aim of this study is to emphasis the use of thermo gravimetrical water content and trace metals analysis to identify the chemical graphical fingerprints of parsley, dill and lovage leaves. Copper, zinc, manganese, iron, nickel and lead have normal concentration values that are not of any risk to human health. Cobalt, chromium and cadmium were not detectable in all studied samples. The water and present trace metals contents associated with mathematical models permits the identification of characteristics specific to the studied vegetable leaves as well as the graphical chemical fingerprints. The study is revealing similar distribution pattern

Plant-soil interrelationship, factor of evolution for bacterial populations

The rhizosphere is influenced by the region, soil and plant roots. The area that is not influenced by plant roots has been named edaphosphere. Plant roots release a wide range of compounds in the rhizosphere, which create unique micro-environments for the microorganisms present in the soil. By its root exudates, species Vicia sativa contributes to an increase in the bacterial density (fact proven by comparison with the control variant), to the improvement of the fertility of the soil (moderately gleyic eutric cambisol) on which it is cultivated and to plant growth. Even there are similarities between the rhizospheric area (culture medium: soil extract), control variants, and respectively edaphosphere (culture medium: soil extract) and rhizospherical bacteria isolated on Topping medium, small differences have been noticed

The behavior of nitrifying microorganisms from a soil cultivated with Lotus corniculatus L.

The knowledge of the behavior of the nitrifying microorganisms is of real use, because the microbial activities related to the nitrogen circuit and especially the nitrification determine the results of the agronomic practices. In this paper, the influence of the Lotus corniculatus L. (IIV culture years) on the nitrifying bacteria and the correlation between the growth of these bacteria and soil moisture was studied.The soil samples were taken during the flowering period (summer season), from the rhizosphere of the pottery, but also from the uncultivated plots (control), placed in the western part of the country. Studies have shown that plants and soil moisture have influenced the evolution of nitrifying bacteria