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In order to study the effect of mineral and organic fertilizers and humic acid on the percentage of total and active carbonates in and outside the rhizosphere and planted with two plants (Maize and Mung bean) and for the flowering and full maturity stages. The experiment was carried out according to a randomized complete block design (R.C.B.D), where the number of experiment treatments was (4), including the comparison treatment, and with three replications for each treatment, and these treatments were randomly distributed to the experimental units, so the number of units became (12) experimental units for each plant (maize and Mung bean), meaning that the total units became (24) experimental units, the experiment's treatments included the mineral fertilizer consisting of fertilizer (Urea+DAP) at one level and according to the fertilizer recommendation for each plant and symbolized by the symbol (M) and the organic fertilization was the addition of (poultry waste) at one level (10) tons ha-1 and symbolized by the symbol (O), and liquid humic acid was added at one level and according to the fertilizer recommendation and symbolized by the symbol (H) and the results of the study were as follows: The treatment of adding humic acid in soil planted with maize in the rhizosphere and outside the rhizosphere at the flowering stage recorded the lowest percentage of total carbonate in the soil amounted to (28.67 and 30.62%), respectively, compared to the comparison treatment, which recorded the highest percentage of total carbonate amounted to (32.17 and 33.62%) respectively, as for the stage of full maturity, the treatment of adding organic fertilizer was the one that recorded the lowest percentage of total carbons, which amounted to (29.61 and 32.00%) respectively, compared to the comparison treatment, which recorded (32.62 and 35.17%) respectively. The treatment of adding humic when added to soil planted with maize achieved a significant decrease in the percentage of active carbonates in and outside layers of the rhizosphere in the flowering stage, as it recorded (4.75 and 5.37%) respectively compared to the comparison treatment, which recorded the lowest value of (7.25 and 7.87%) respectively, while in the stage of full maturity, the treatment of adding humic acid achieved a significant decrease, as it recorded (2.08 and 2.67%) respectively, compared to the comparison treatment, which recorded (6.12 and 6.50%) respectively. The treatment of adding humic acid to a soil planted with Mung bean in both in and outside layers of the rhizosphere at the flowering stage achieved a significant decrease in the percentage of total carbonate in the soil, as it was recorded (28.50 and 31.00%) respectively, compared to the comparison treatment, which recorded (30.87 and 32.87%) respectively, in the fully mature stage, the addition of mineral fertilizer (Dap+urea) outperformed, as it scored (25.33 and 28.50%) respectively, compared to the comparison treatment, which recorded (31.00 and 33.67%) respectively. The treatment of adding humic acid when it was added to the soil planted with Mung bean at the two layers of the rhizosphere and outside in the flowering stage gave the lowest percentage of active carbonates amounting to (4.17 and 5.17%) compared to the comparison treatment which recorded (6.17 and 7.00%) respectively, in the stage of full maturity, the humic addition treatment recorded the lowest percentage of active carbonates in the rhizosphere layer, reaching to 3.15% compared to the comparison treatment, which recorded 4.48%. [ABSTRACT FROM AUTHOR]

A field experiment was carried out in order to study the effect of mineral and organic fertilizers and humic acid on the total and active carbonates minerals percentage in the rhizosphere soil and outside it at the flowering and full maturity stages of Sorghum and Sunflower crops. The experiment was carried out according to a randomized complete blocks design (RCBD) at three replications. Each experiment included four treatments: the adding of mineral fertilizer (urea+DAP) according to the fertilizer recommendation for each plant, the adding of organic fertilizer (poultry waste) at a 10 ton ha−1, the adding of liquid humic acid according to the fertilizer recommendation (5 L ha−1) as well as the control treatment (without adding the fertilizers). The Results showed that the adding of mineral fertilizer to the soil planted with Sorghum achieved a lowest percentage of total carbonate minerals (27.25%) in the rhizosphere soil at the full maturity stage and percentage of active carbonates in the soil (2.58 and 3.08%) in the rhizosphere soil and outside it respectively at the full maturity stage, while the adding of liquid humic acid gave a lowest percentage of active carbonates (5.42%) in the outside of rhizosphere soil at the flowering stage. Also, the adding of organic fertilizer to the soil planted with Sunflower gave a lowest percentage of total carbonate (28.33 and 30.58%) respectively in the rhizosphere soil and outside it at the full maturity stage, whereas the adding of humic acid gave a lowest percentage of active carbonates (6.25%) in the outside of rhizosphere soil at the flowering stage, while the adding of mineral fertilizer gave a lowest percentage of active carbonates (2.96 and 3.42%) respectively in the rhizosphere soil and outside it at the full maturity stage. [ABSTRACT FROM AUTHOR]

This paper aims to test the effect of add a vermicompost, seaweed extracts, and Urea to the soil on the total number of fungi during flowering and complete maturity. Throughout the 2019-2020 fall season, an experiment was conducted on one of the farms in the Nouriya area of Iraq's Al-Diwaniyah governorate. The experiment, which followed a global trend, used three replications and a fully randomized sector design. The initial factor was the addition of vermicompost fertilizer in three stages (0, 2 and 4 tons h-1), the second factor was the addition of seaweed extract in two levels (0 and 40 kg h−1) denoted by S0 and S1, and the third factor was the addition of urea in three stages (0, 120 and 240 kg N h−1) denoted by U0, U1 and U2, respectively. In maturity of the analyzed descriptions, the tages of vermicompost varied considerably, with level V2 getting the greatest results for the quantity of fungi in the blossoming and complete maturation levels (32.61 103 and 27.40 103 CFU gm−1 dry soil, respectively). The addition of seaweed extracts S1 had a substantial effect on total fungus populations in the blossoming stage (30.66 103 CFU gm−1 dry soil), but not in the complete maturation levels. When U1 Urea was added, the amount of fungus in the blooming stage (26.62 103 CFU gm-1 dry soil) increased dramatically. [ABSTRACT FROM AUTHOR]

The extensive use of synthetic fungicides in controlling plant disease generates detrimental impacts on the environment and human health. In response to this problem, an alternative method was developed, known as biological control using antagonistic microorganisms. The plant rhizosphere is rich in microbes, one of which is a group of fungi. The aim of the present work was to evaluate the biocontrol potential of rhizosphere fungi against Fusarium oxysporum, a phytopathogen that causes anthracnose disease. A total of twenty-seven rhizosphere fungi were isolated from different tissue parts of grape (Vitis vinifera). Results demonstrated that most rhizosphere fungal isolates showed some inhibitory action over the growth of F. oxysporum during dual culture growth. Rhizosphere isolate G11 showed the highest antagonistic activity against F. oxysporum with 86.59% percentage inhibition radial growth (PIRG). In conclusion, rhizosphere fungi isolated from V. vinifera indicate the potential as biocontrol agents. It is hoped that the finding of isolated rhizosphere fungi in this study with antagonistic activity against F. oxysporum pathogen may be used in biocontrol programs for plant disease in the region. [ABSTRACT FROM AUTHOR]

Pepper is one of the plantation products with high economic value. Cultivation businesses are generally carried out independently by the community using conventional methods. The limited availability of subsidized fertilizers is one of the obstacles faced by farmers, while the price of non-subsidized fertilizers is quite high. This is certainly a burden for farmers considering pepper is a type of plant that requires large amounts of nutrients. The utilization of soil microorganism services as biofertilizers is an alternative to replace the use of inorganic fertilizers. The purpose of this study was to identify the types of beneficial soil microbes in the roots of pepper plants, especially non-symbiotic nitrogen fixing bacteria and phosphate solubilizing bacteria, as well as phosphate solubilizing fungi. The isolation of bacteria was carried out by the spread method on agar media, while the isolation of fungi was carried out by the pour method. The density of microorganisms was calculated by the Total Plate Count (TPC) method. Total soil microorganisms were quite low, i.e., 8.8 × 105 - 3.1 × 107 colonies/gram of soil. Bacterial characterization was carried out by observing the macroscopic morphology of the colonies, Gram staining and endospores, and catalase and motility tests. Fungal characterization was carried out by observing macroscopic and microscopic morphology, which included hyphae, spore-producing, and spore-forming. Exploration of potential soil microorganisms carried out on pepper rhizosphere resulted in 3 groups of potential microorganisms, namely nitrogen-fixing bacteria, phosphate solubilizing bacteria and phosphate solubilizing fungi. The types of nitrogen-fixing bacteria obtained were from the genera Rhizobium, Bradyrhizobium, Acetobacter, Azotobacter, Azospirillum, and Clostridium. Phosphate solubilizing bacteria obtained were Azotobacter, Bacillus, Pseudomonas, and Thiobacillus. In contrast, the types of phosphate solubilizing fungi that have been isolated are Penicillum, Aspergillus, and Trichoderma. All isolates have the potential to be used as biofertilizers, but further tests are needed to determine which isolates have the best ability to provide optimal effects on plants. [ABSTRACT FROM AUTHOR]

During routine nematological surveys conducted in 2016-2021 in the Crimean Peninsula, Xiphinema pachtaicum and Xiphinema simile were the most frequently encountered dagger nematodes in the rhizosphere of grapevines. This paper includes morphological, morphometric, and molecular data of these species from this territory. [ABSTRACT FROM AUTHOR]

The emergence of resistant pathogenic bacteria to antimicrobial drugs has serious concern worldwide because it can pose a great threat to public health. Several pathogenic bacteria have been identified to develop resistance to more than one type of antimicrobial drugs, such as Staphylococcus aureus, Streptococcus pyogenes, Mycobacterium tuberculosis, Haemophilus influenzae, Neisseria gonorrhoeae, Klebsiella pneumoniae, and Escherichia coli. To overcome this problem, innovation is needed to find a novel antimicrobial agent from natural resources with a different mechanism of action different from antimicrobial drugs derived from synthetic materials in fighting bacteria pathogens. This research aimed to isolate local isolates of Actinomycetes from the mangrove soil of Wonorejo Surabaya and tested the ability (screening) of the local isolates of Actinomycetes to produce bioactive compounds to fight pathogenic bacteria. Soil samples were taken from a 6-10 cm depth and then stored in a sterile plastic container. It was taken immediately to the laboratory and stored at 4oC. The isolation method is carried out by processing the mangrove rhizosphere soil samples. Furthermore, Actinomycete bacteria are grown on media then purified on specific media. Actinomycete isolates obtained were then tested for antibacterial compounds using the antagonistic test against Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae. The isolation results obtained five isolates of actinomycete bacteria. The antagonistic test showed two isolates with moderate Escherichia coli and Klebsiella sp inhibition. Actinomycete bacterial isolates obtained had the potential to produce antibacterial. [ABSTRACT FROM AUTHOR]

The aim of this study is to clarify the relationship between the root secretions of some important plants in our food and the bacteria that produce the rooting hormone (IAA). The plants were (Lepidium sativum), (Eruca sativa) and (Anethum graveolens). After isolation of (IAA) from each plant rhizospheric soil, it was tested in rooting and growth of different stem cuttings, for two seasons (2018-2019), to evaluate the activity on rooting and vegetative growth. The results shown that (Eruca sativa) rhizospheric soil is characterized by giving the highest results in rooting and vegetative growth for the test plants. The results indicated the presence of P. putida and P, florescence bacteria in the (Eruca sativa) rhizospheric and P. putida in (Anethum graveolens) rhizospheric soil. [ABSTRACT FROM AUTHOR]

Simplicillium lanosoniveum strain CG888 (MT 081944.1) is one of the fungi was isolated from the results of rhizosphere soil exploration in Gondang Manis Jamaica apple (Syzygium malaccense L), Perak District, Jombang Regency, Indonesia, which is included in the Brantas watershed area. Sampling was conducted in July 2020, using a one diagonal sampling method with five sample points. Purification of fungal isolates from soil samples was carried out using the dilution method, up to a level of 10−2. The DNA extraction results were amplified using the PCR technique. ITS4 and ITS5 primers were used for the amplification of the ITS rDNA region. The sequencing results were analyzed based on GenBank data at the National Center for Biotechnology International (NCBI). using the Basic Local Alignment Tools (BLAST) program. The phylogenic structure was determined using MEGA 7.0 software. Based on macroscopic, it has white colonies on the upper surface, and the lower is yellowish. Yellowish color is found in the old colonies or the center of the colony, and sphere. The structure is like cotton with a thick mycelia arrangement. Microscopically, The hyphae has transparent and septate, branching, tapering to the tip, and at the end formed phialid. The conidia are transparent, small and in round shape. Simplicillium lanosoniveum strain CG888 (MT 081944.1) as one of the antagonist fungi among other fungi that have been found and identified, so that it can support soil in the Brantas watershed area has the potential as a suppressive soil. [ABSTRACT FROM AUTHOR]

Water saturated rhizosphere (WSR) can be caused by partial submergence of growing substrate such as in floating culture system (FCS). This WSR directly influence metabolism and development in root and leaves. This study focused to assess responses of root and leaves of nine Indonesian varieties of chili peppers exposed to two levels of WSR conditions, i.e. 1/3 WSR (W1) and fully WSR (W2). These WSR treatments were compared to untreated control plant (C0). The results showed that WSR treatments decreased leaf parameters such as number of existing leaves at end of treatments, SPAD value, total leaf area (TLA), specific leaf dry weight (SLDW), and relative turgidity (RT). Effect on root parameters included decrease of root length (RL) and ratio of root dry weight (RDW). However, 1/3 WSR treatment exhibited higher values of both root and leaf parameters than those of control plants in some varieties. There were comparable patterns of RLER in the 1/3 WSR treated plants (W1) and untreated control (C). Based on results of this study, it is recommendable to allow up to 1/3 lower part of growing substrate to be submerged in floating culture system of chili pepper [ABSTRACT FROM AUTHOR]

Microbial communities associated with the plant rhizosphere play an important role in carbon sequestration, regulation of nutrient cycling, and the efficient functioning of the ecosystem as a whole. The diversity of microorganisms inhabiting the plant rhizosphere and their complex interactions with the host plant significantly affect the morphology, physiology, growth, development, and health of plants. At the same time, it is known that the soil microbiome diversity is affected by the type of soil, the type of cultivated crop, and the method of tillage. In this study, the abundance and diversity of cultivated bacteria of the rhizosphere microbiome of wheat was assessed. Rhizospheric soil samples were taken from 5 fields with different types of soils (Greyzem, Chernozem, Podzols, Podzoluvisols, Podzoluvisols). Cultivated bacteria from the rhizosphere soil were isolated on meat-peptone and soil agars, and their number was determined. It has been established that the cultivated bacterial rhizobiome was least diverse in wheat plants grown on medium podzolic soil. The MALDI-TOF method was used to identify isolated cultivated isolate species. The genera Achromobacter, Acinetobacter, Bacillus, Microbacterium, Paenibacillus, Pseudomonas, Stenotrophomonas predominated among the isolated bacteria. [ABSTRACT FROM AUTHOR]

In order to preliminarily explore the effects of different base fertilizers on soil ecology, taking Medicago sativa as the research object, the changes of urease, sucrase and catalase activities in Medicago sativa growing soil after applying different base fertilizers (A1: adding 210g cow dung I basin, A2: adding 250g cow dung I basin, B1: adding 0.5g compound fertilizer I basin, B2: adding 1.0g compound fertilizer I basin) were discussed. The results showed that the soil invertase content of Medicago sativa Planted with compound fertilizer (B1) was the highest, up to 48.884mgIg. The statistical comparison of the average content of soil sucrase is as follows: cow manure (A2) > compound fertilizer (B2) > cow manure (A1) > compound fertilizer (B1) > no base fertilizer (CK). The soil urease content of Medicago sativa Planted with cow dung (A2) was the highest, which could reach 6.059 mg I g. The statistical comparison of the average content of soil urease is as follows: cow manure (A2) > cow manure (A1) > compound fertilizer (B2) > no base fertilizer (CK) > compound fertilizer (B1). The soil catalase content of Medicago sativa Planted with compound fertilizer (B1) was up to 0.09046mgIg. The statistical comparison of the average content of soil catalase is as follows: compound fertilizer (B1) > cow dung (A2) > no base fertilizer (CK) > cow dung (A1) > compound fertilizer (B2). The application of different base fertilizers had a very significant effect on the contents of soil urease, sucrase and catalase. The application of cow manure significantly increased the activities of soil sucrase and urease, and the effect was more significant with the increase of fertilizer application. The application of organic fertilizer (cow manure) significantly increased soil enzyme activity than inorganic fertilizer (compound fertilizer). [ABSTRACT FROM AUTHOR]

The ability to colonize on plant roots is recognized as one of the most important characteristics of the beneficial fungi. To study these properties, we have developed and created a system for cultivating fungal microorganisms under sterile conditions on the surface of cellulose cylindrical tubes, into which a nutrient solution simulating plant exudate was constantly fed. This system simulates the development of microorganisms on the surface of the root system and allows to study the interaction of microorganisms with each other during their surface growth with a constant supply of exudates to it. Trichoderma viride and Fusarium oxysporum were selected as objects for studying the interaction when they grew on nutrient medium simulating water-soluble exudates of cucumber. The concentration of the model of cucumber exudates in the supplied solution corresponded to 250 mg/l. Growth kinetics studies using this cultivation method have shown that Trichoderma viride is able to grow under such conditions, completely covering the surface of the cellulose tube. The synthesis of enzymes of the lytic series, even at exudate concentrations of about 50 mg/l, was not observed, which indicates the presence of the effect of catabolic repression in this strain, even at such low concentrations of exudates. Studies of the interaction of Trichoderma viride with Fusarium oxysporum, after adding the latter to the surface formed by the mycelium of Trichoderma viride, showed that Fusarium oxysporum cells were not detected after a day of co-cultivation. Thus, the presented model of the method of cultivation of fungal cells made it possible to elucidate the interaction of Trichoderma viride and Fusarium oxysporum during their co-cultivation on media simulating cucumber exudates. The study showed that a physical model could be used to make reasonable predictions about the behaviour of microorganisms in soil–root systems. [ABSTRACT FROM AUTHOR]

Unequal distribution of annual precipitation is negative trend of last year’s influencing primary agricultural field production. One of the natural possibility for elimination of this gesture is to increase patience to the actual conditions and functionality of root system of the plants. Among possible abilities of field crops protection to abiotic stresses during vegetation period belongs strengthening of their natural tolerance. Present situation of soil degradation does not allow to plants sufficiently deploy rooting system so they are not able naturally tolerate to these abiotic stresses, as well as it decreases the efficiency and utilization of mineral nutrients applied in mineral fertilizers. The study is aimed to analyze the advancement possibilities of biological soil systems due to biostimulation of plant root system by soil biostimulants in comparison to common fertilization by NPK type mineral fertilizer. There were prepared 5 variants in experiment: control (without fertilization), NPK fertilization and three variants with soil biostimulant - rhizosfere activator Explorer 20, which sustain microbiological activity close to root system and mineralization processes in the soil. There were observed the changes of oxidable carbon (Cox) content, soil organic matter (SOM) content, C/N ratio and nutrient content, especially N-forms. There was an increase in plant biomass production (on average more than 15% compared to control variant) and an increase in SOM content (on average more than 10% compared to control variant and NPK variant). Due to the improved rooting system increased the content of soil organic matter. Increasing content of SOM had a positive effect on Cox values and also on the release of accessible nutrients into the soil solution. This result was obtained primary due to increased soil biological activity and improved deployment of roots and their symbiotic rhizosphere function. The study confirms that there is an alternative to conventional plant nutrition that positively affects plant growth and soil quality. [ABSTRACT FROM AUTHOR]

The main purpose of our study was to understand the effects of phosphorus-solubilizing bacteria on soil enzyme activity and microbial community in soybean rhizosphere. We applied wj1 and wj3 bacterial liquids to different treated soils, and observed the changes of soil activity in Soybean Rhizosphere under the action of exogenous phosphorussolubilizing bacteria at different growth stages. According to the results of this study, when strain wj1 is in the growth stage, it can promote the activity of phosphatase in black soil. The number of microorganisms in soybean rhizosphere is affected by the amount of Phosphate solubilizing enzyme added to black soil, and the strains can promote the increase of the number of phosphorus-solubilizing bacteria and nitrogen-fixing bacteria in black soil to a certain extent. [ABSTRACT FROM AUTHOR]

The rhizosphere defined as zone surrounds the root that it physical, chemical, and biological character directly influenced by root activities. The rhizosphere is characterized by high microbiological activities compared to bulk soil and affected the plant performance. The objectives of this research were to determine soil respiration and total population of soil microbes, including fungi and bacteria, phosphate solubilizing microbes, and organic matter decomposer microbes. Soil samples were collected from rhizosphere zone (0-20 cm) of kemenyan bunga, kemenyan durame, kemenyan batak and kemenyan minyak in Pardomuan village, Sitellu Urang Julu-Pakpak Bharat, North Sumatera. Microbial population was calculated using plate count method and soil respiration measured using jar methods. The result showed that the highest fungi and bacterial population were found under kemenyan durame rhizosphere those were 13.4 x 107 and 15.7 x107 CFU mL-1. The highest phosphate solubilizing microbes population (96.8 x104 CFU mL-1) was also found in kemenyan jurame rhizosphere. The highest organic matter decomposer microbe found in kemenyan minyak rhizosphere those were 25.1 x104 (fungi) and 73.2 x 104 CFU mL-1 (bacteria). The highest respiration (3.23 mg CO2 100 g-1 day-1) was also found in kemenyan jurame rhizosphere. [ABSTRACT FROM AUTHOR]

Industrialization and ever-growing population are resulted in exploitation of natural resources and cause flushing of toxic contaminants into the environment. Present study investigates the isolation and identification of beneficial bacterial population from the rhizosphere zone of two plants – red clover (Trifolium pratense) and white sweet clover (Mililotus albus) growing in vicinity of Cr mine, near Verkhnyaya Pyshma town, Russia. Significant number of plant growth promoting rhizobacteria capable to solubilize tri-calcium phosphate and produce indole-3-acetic acid with and without Cr (0, 100 and 200 mg/L) was studied at 24 h and 120 h. For most of the bacterial isolates, the phosphate solubilization and indole-3-acetic acid production was reduced with increase in Cr concentration at 24 h however, enhanced phosphate solubilization and decreased Indole-3-acetic acid was found at 120 h. The study suggests that isolated bacterial strains are capable to tolerate 100 mg/L of Cr without showing any significant change in results and can help in bioremediation of Cr contaminated sites. [ABSTRACT FROM AUTHOR]

The paper reports the first results of vegetation experiments confirming the earlier observed in vitro sensitizing activity of extracellular elicitors of F. sambucinum FS-94 toward P. nodorum. The data of a small-plot field experiment showing a possibility of using FS-94 culture liquid containing these resistance-eliciting metabolites to reduce effective dosages of Folicure BT, EC 25% (a. i. tebuconazole and triadimefon, triazole derivatives) are also presented. [ABSTRACT FROM AUTHOR]

Indole-3-Acetic Acid (IAA) known as an important growth hormone that some microorganism can produce it. Bacteria is one of microorganism which can produce IAA such as isolate TPK5b2 were isolated from paddy rhizosphere and culture collection of Agriculture Microbiology Laboratory. The aim of this study was to determined the optimum pH for IAA production by isolate TPK5b2. IAA production by isolate TPK5b2 was measured using a colorimetric method based on absorbance in UV-Vis Spectrophotometer. The highest IAA concentration by isolate TPK5b2 showed in pH 7.00 with IAA concentration 17.491±1.70 µg/mL after 72 hours incubation instead of the other treatment. [ABSTRACT FROM AUTHOR]

Bacteria lived in Amorphaphallus konjac rhizosphere soil have the potential ability of antagonistic bacterial pathogen activity against to Erwinia carotovora subsp carotovora (Ecc). The paper was to study and analyze all strains of 18 bacteria isolated from A. konjac rhizosphere soil with strong antagonistic effect against to Ecc and to identify antagonistic bacteria with morphology, physiology and biochemistry characteristic. The antagonistic bacterial pathogen activity of different bacterial strains were significantly different. Five of 18 strains isolated from A. konjac rhizosphere soil, including AKSB03, AKSB05, AKSB08, AKSB13 and AKSB16 was screened with antagonistic wider more than 15 mm in first screening test. Strain AKSB08 and strain AKSB16 had a strong antagonism activity for Ecc with antagonistic wider more than 20 mm in second screening test. Strain AKSB08 and strain AKSB16 belonged to Bacillus with morphology, physiology and biochemistry characteristic. [ABSTRACT FROM AUTHOR]

Plants do not grow axenically in nature, but host a diverse community of microorganisms, termed as plant microbiota, colonizing different niches, both inside and outside their tissues, in the endosphere and ectosphere, respectively. These microorganisms are involved in major physiological processes, such as plant nutrition and plant resistance to biotic and abiotic stress factors. The aim of the research was to investigate the normal microbiota of rare plant species (listed with different degrees of danger in the "Red Book vascular plants in Romania", Red Lists, IUCN, Bern Convention Habitats Directive, CITES), found in natural habitats, in order to define some microbiological associate with soil composition that could be further used as parameters for measuring the plant growth. Our focus was oriented to several rare plant species from natural habitats of Romania, with localization in southern Dobrogea: Adonis vernalis, Opopanax chironium, Asphodeline lutea. Paeonia tenuifolia (Hagieni Natural Reserve, Constanta), Potentilla emilii-popii (Sipote, Constanta). In order to analyse the normal of composition associated soil microorganisms', we sampling the rhizosphere from each plant species and processed for isolation and biochemical identification of the cultivable microbial species. Also, the physical and chemical properties of the rhizosphere samples were investigated using modern technics (Inductive coupled plasma atomic emission spectrometry (ICP-AES)), in order to determinate the availability of metals in rhizosphere and the pH values. The results showed that the phylogenetic composition of these communities is composed by relatively few bacterial phyla, including Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria, with variations depending on the plant species and soil characteristics. The availability of different metals (Al, Fe, Mn, Cu, Zn) in rhizospheres was influenced by the pH change and chemical compositions of root exudates. [ABSTRACT FROM AUTHOR]

The aim of this three-year study was to determine the effect of different vineyard vegetation cover on organic matter content in the soil, the content of available nutrients and essential soil properties. Soil samples were taken from between rows of vines, where species-diverse mixtures for planting vineyards were sown. For observation, three localities of the Czech Republic with different soil and climatic conditions were chosen (Popice, Mikulov and Znojmo). Two variants of vineyard greening mixes were established: Variant 1 - Diverse/Rich mix and Variant 2 - Dry mix. The obtained results showed a significant increase in soil organic carbon (Corg) and content of available phosphorus through the monitored years. The better rooting ability of mixes increased the soil organic component which is connected with Corg as well as the release of accessible phosphorus into soil solution mainly in 0.15-0.30 m layer. This result is primarily due to increased biological activity in deeper layers of the soil and better rhizosphere function. [ABSTRACT FROM AUTHOR]

Biochar is carbonized organic matter, which is prepared by pyrolysis and it content high amount of carbon. This material is currently very often mentioned in carbon sequestration and as an additive improving physicochemical and biological soil functions, especially soil aggregation, conductivity or pH. Thus biochar could be usefully toll for decreased erosion risk. The influence of biochar on soil microorganisms is still big question. Results of scientific work differ much. Problematic component of biochar is aromatics formed during pyrolysis of organic material and can be toxic to most of microorganisms. However, some representatives of microbial community can use them as a source of nutrients and energy. Thus, their contribution, together with oxidation, can lead to degradation of aromatic compounds over time. Anyway, this process can be very long lasting. In our experiment, we tried to accelerate these natural processes by means of a simple system (biochar inoculated by native soil microflora in aquatic environment). Afterwards, we compared the effect of conventional (fresh) biochar and our biochar activated on root colonisation of experimental plants by arbuscular fungi (AMF). [ABSTRACT FROM AUTHOR]

Rhizosphere moulds have an activity to reduce the growth of Fusarium oxysporum f.sp. lycopersici. Seventeen species which have antagonistic effect against F. oxysporum f.sp. lycopersici were identified from 47 isolates. Screening of the inhibition growth on F. oxysporum f.sp.lycopersici confirmed that Aspergillus fumigatus and 1 isolate Aspergillus sp. inhibit the growth of F. oxysporum f.sp. lycopersici by producing non-HCN volatile and iturine non-volatile antifungal and protease, while Aspergillus niger and 1 isolate Aspergillus sp. inhibit the growth of the pathogen by producing non-HCN volatile and iturine non-volatile antifungal, Fusarium oxysporum and Humicola fuscoatra inhibit the growth of the pathogen by producing non-HCN volatile, non-iturine non-volatile antifungal, and protease, A. fumigatus (4 isolates), A. niger (2 isolates), Aspergillus parasiticus (1 isolate), Aspergillus sp. (2 isolates), Gongronella butler (1 isolate), Paecilomyces lilacinus (1 isolate), Penicillium sp.1 (1 isolate), Penicillium sp.2 (1 isolate), Penicillium sp.3(1 isolate) inhibit the growth of the pathogen by producing non-HCN volatile and non-iturinenon-volatile antifungal, Mucor sp. and Trichoderma sp. inhibit the growth of the pathogen through the competition and production of non-HCN volatile and non-iturine non-volatile antifungal, and the other isolates inhibit the pathogen by producing non-HCN volatile antifungal. [ABSTRACT FROM AUTHOR]

Today, the chitinous wastes are used by several companies to produce chitin and chitosan, which are used in various biotechnological applications, particularly in the agricultural sector which is a Key sector for sustainable development. Improving the quality of the plant production requires an improvement in its rhizospheric microbial composition , which called Plant Growth Promoting Rhizobacteria (PGPR), the role of these microorganisms not only the improving the quality of nutrients present in the rhizosphere, but also assure the plant protection against phytopathogenic agents. The objective of this work is to study the effect of chitinous waste on Triticum durum (wheat) rhizospheric microflora, by mixing (W/W) the wheat soil with chitinous waste at different concentration. Twentieth days of Monitoring, showed a significant effects on the soil microflora and pH. The results of the first ten days of treatment revealed in elevation in bacterial number with Bacillus genus dominance and absolute absence of fungi even saprophytic or phytopathogenic, whereas the results of the last ten days were characterized by the diversity of wheat rhizospheric microflora with appearance of Plant Growth Promoting Rhizobacteria such as N2 fixing bacteria and those involved in plant protection. [ABSTRACT FROM AUTHOR]

With urbanization and rapid industrial progress, water bodies around the world are getting highly polluted with metals. Bacteria have evolved several mechanisms to adapt to heavy metal contaminants thus representing a potential source for bioremediation process. The present study deals with isolation, identification and characterization of metal tolerant bacteria (MTB) from the rhizosphere of Eichhornia crassipes (water hyacinth) collected from the backwaters of Cochin (South India, 9°58' N, 76°17' E). Depending on the metals they tolerated (Pb, Cu, Fe, Zn, & Co), the metal tolerant bacteria (MTB) were labeled as Pb-1 to Pb-3, Cu-1 to Cu-4, Fe-1 to Fe-4, Zn-1 to Zn-4, and Co-1 to Co-2. No cultures tolerated and grew in the presence of Hg and Cd. Cultures were identified on the basis of 16S rRNA gene sequence analysis. Morphological and compositional studies were conducted using computer-assisted Scanning Electron Microscopy equipped with Energy Dispersive Spectroscopy (SEM/EDS). The maximum tolerable concentration (MTC) which is the highest concentration having minimum effect on the growth of the isolates were determined and found to be <2mM for CuSO4, <3mM for ZnSO4, <3.5mM for CoCl2, <12mM for PbNO3 and 25mM for FeCl3. They were further screened for antibiotic sensitivity and biological activity according to Kirby-Bauer disc diffusion method. The MTB under metal stress condition showed significant biological activity against clinical pathogens, fouling bacteria and selective plant and fish pathogens indicating their biotechnological application in medicine, agriculture and aquaculture. [ABSTRACT FROM AUTHOR]

The article discusses a study which aimed to determine the immunostimulant and antimicrobial properties of selected Streptomyces ssp. in the rhizosphere soil of a medicinal plant named Acalyphaindica. Results show different colours of aerialand substrate mycelia which is due to nutrient which triggers certain genes resulting in the expression of different metabolic products. It was also found that aside from its immunostimulant property, the Streptomyces sp is an effective cell protein.

Measurements along the length of an optical fibre sensitised to pH and moisture will enable monitoring of spatial differences around the root systems of developing plants. Mapping of spatial variations and temporal changes in moisture and pH provides a methodical approach for imaging soil behaviour and potentially the effect of plant roots and associated soil micro-organisms, enabling optimisation of crop yield. [ABSTRACT FROM AUTHOR]

Nematodes were studied at sites with low, medium and high level of soil metal contamination in the area of a non-ferrous metal plant. Soil total metal concentrations ranged from values below their maximum permissible concentrations (MPC) in soil to 48, 44, 16 and 4 times higher than the MPC for Cd, Pb, Zn and Cu, respectively. Nematodes were isolated from uncultivated, monoculture stands of the metal accumulating mustard weed (Lepidium draba L., Brassicaceae) in April, May and June 2015. Overall, 55 nematode genera were identified during the investigation: 50 genera at low, 39 at medium, 37 at high levels of soil metal pollution. Several nematode diversity measures and the specific responses of some nematode genera differentiated the three investigated sites. Both nematode richness (S) and diversity (H') of genera correlated negatively with the soil metal concentrations in the following order: Cd>Pb>Zn>Cu. Several genera (Alaimus, Cylindrolaimus, Paramphidelus, Scutylenchus, Steinernema) were common at the least contaminated site and were either rare or not found at the rest of the sites. Some genera (Clarkus, Filenchus) were most abundant at the medium level of contamination. The abundance of eleven genera correlated negatively with the metal concentrations in the samples. Most of the negative correlations (Acrobeles, Coslenchus, Geomonhystera, Plectus) were in the following order: Cd>Zn>Pb>Cu. The abundance of nine genera correlated positively with the metal concentrations and most of their correlations were in the order: Cu>Pb>Zn>Cd. Faunal profile analyses of the free living nematode assemblages revealed higher values of Structure index (SI) at low (75-91%) and medium (77-87%) levels of contamination in comparison with the most polluted site (35-46%). Nematode structure metabolic footprints (SFP) at low and medium levels of contamination were much higher than at the high pollution level. Both SI and SFP at the medium level of metal contamination indicated low bioavailability and low toxicity of Pb (1290 mg kg soil), Cd (34 mg kg soil), Zn (1779 mg kg soil) and Cu (190 mg kg soil) for the free-living nematodes, isolated from the rhizosphere of the mustard weed at this site. The rhizosphere of the metal accumulating plant might be protective for these nematodes, providing conditions of reduced bioavailable metals in contaminated soil during the vegetation period of the plants. [ABSTRACT FROM AUTHOR]