EFFECT OF ORGANIC AMENDMENTS ON RHIZOCTONIA AND ACCOMPANYING MICROFLORA IN SOIL

1967 ◽  
Vol 13 (6) ◽  
pp. 643-650 ◽  
Author(s):  
Y. Henis ◽  
B. Sneh ◽  
J. Katan
Keyword(s):  
Soil Microorganisms ◽  
Organic Amendments ◽  
Experimental Period ◽  
Soil Microflora ◽  
Modified Method ◽  
Bean Plants ◽  
Infection Index ◽  
Cotton Plants ◽  
Oat Straw ◽  
Period Decrease

The effect of oat straw, green bean plants, and cellulose on the infection index and saprophytic activity of Rhizoctonia, and the effect of chitin, N-supplemented oat straw, and green cotton plants on the infection index, saprophytic activity, and soil microflora was tested. A modified method for counting Rhizoctonia-antagonistic bacteria, actinomycetes, and fungi was developed. A relationship between efficiency of the amendments in decreasing infection index and in suppressing the saprophytic activity of Rhizoctonia was observed at the end of the experimental period. Decrease in infection index and saprophytic activity was accompanied by increase in counts of general and antagonistic soil microorganisms. This increase was especially pronounced in chitin-amended soil. The possible mechanism of the biological control of Rhizoctonia by chitin is discussed.

Responses of soil microorganisms to volatile exudates from germinating pea seeds

1985 ◽  
Vol 63 (6) ◽  
pp. 1040-1045 ◽  
Author(s):  
J. M. Norton ◽  
G. E. Harman
Keyword(s):  
Soil Microorganisms ◽  
Sclerotium Rolfsii ◽  
Hyphal Growth ◽  
Soil Microbial Activity ◽  
Soil Microflora ◽  
Natural Soil ◽  
Soil Microbial ◽  
Aged Seed ◽  
Seed Rot ◽  
Pea Seeds

Responses of soil microorganisms to volatile exudates from germinating pea seeds of differing quality were determined. Germination of sclerotia of Rhizoctonia solani and Sclerotium rolfsii and subsequent hyphal growth were stimulated by exposure to volatiles from aged but not nonaged pea seeds. Hyphae grew preferentially toward aged seeds. In natural soil, bacterial and fungal populations showed significant increases after exposure to volatiles from aged seed. For example, Fusarium spp. and Pseudomonas spp. showed increases of 79 and 2200%, respectively, over their original population levels after a 48-h exposure to volatiles. Conversely, Pythium populations and associated seed-rotting potential of soil decreased in natural soils exposed to volatiles. In autoclaved soils infested with P. ultimum (PHP4), Pythium populations increased dramatically after exposure to volatiles from aged pea seeds. In soils infested with either soil fungi or bacteria in addition to P. ultimum, Pythium levels remained constant or decreased, respectively, with time of exposure. Exposure to the volatiles from aged pea seeds stimulated soil microbial activity. These results suggest that Pythium germlings, when unable to reach a host, are subjected to microbial antagonism in the presence of the native soil microflora. A decrease in cucumber seed rot coincided with decreases in Pythium numbers.

MINIMIZING SOIL CULTIVATION INFLUENCE FOR FERTILITY STATUS OF HEAVY LOAMY SOILS IN SPRING AND WINTER WHEAT SEEDING

2016 ◽  
Vol 1 (2) ◽  
pp. 7-11
Author(s):  
Мельникова ◽  
Natalya Melnikova ◽  
Нечаева ◽  
Elena Nechaeva ◽  
Редин ◽  
...  
Keyword(s):  
Soil Fertility ◽  
Soil Microorganisms ◽  
New Technologies ◽  
Mechanical Load ◽  
Active Surface ◽  
Soil Microflora ◽  
Point Of View ◽  
Forest Steppe ◽  
Biochemical Processes

The purpose is to justify the use of minimum and zero tillage in conditions of forest-steppe Zavolzhye region from the position of the biological activity of the soil. One of the factors forming and determining the fertility of the soil, is the activity of microorganisms that inhabit it, the active surface which reaches up to several hundred acres for 1 ha of surface topsoil. Important role in building of soil fertility is the number of major groups of microorganisms, which, being the catalysts of metabolism, objectively reflect the nature of biochemical processes. Another academician S. P. Kostychev (1937) pointed out that without the study of biodynamics the knowledge of the soil, especially from the agronomic point of view, may not be complete. Microorganisms occupy a key position in maintaining biochemical capacity of the soil, so monitoring of soil microflora is essential for the maintenance and reproduction of its fertility. This work is devoted to studying the role of soil microorganisms in the process of maintaining and reproduction of soil fertility in the development of new technologies in agriculture. The article presents data on the effect of basic tillage on the number of different groups of soil microorganisms (micromycetes, bacteria, actinomycetes), Shows the number of soil microorganisms, such as micromycetes (mold fungi) and bacteria are significantly influenced by seasonal changes in temperature and humidity than the soil treatment methods. From which it follows that the reduction of the mechanical load on the soil in the forest-steppe of Zavolzhye a significant impact on the number of major groups of microorganisms has not.

The effect of urea on the utilization of ground, pelleted roughage by penned sheep: I. Food intake, live-weight change and wool growth

1969 ◽  
Vol 72 (2) ◽  
pp. 251-259 ◽  
Author(s):  
J. B. Coombe ◽  
G. K. Preston
Keyword(s):  
Weight Loss ◽  
Food Intake ◽  
Weight Change ◽  
Live Weight ◽  
Basal Diet ◽  
Experimental Period ◽  
Mineral Supplement ◽  
Wool Growth ◽  
Crystalline Urea ◽  
Oat Straw

SUMMARYIndividually-penned adult Merino wethers were fed for 16 weeks on a basal diet of ground, pelleted oat straw or Phalaris straw. Urea was supplied either in a salt-urea block containing 30% urea, or as crystalline urea incorporated into the pellets. A commercial mineral supplement was given during the first 8 weeks, but this was replaced with a laboratory-prepared mineral mix during the second 8 weeks.Urea supplementation significantly reduced live-weight loss. Over the 16 weeks control sheep lost a mean of 14·5 kg, and supplemented sheep 8·7 kg body weight. Most of this response to urea occurred during the second half of the experimental period.Food intakes of all sheep increased over the first 2 weeks and then fell. In the unsupplemented groups, levels of intake then remained fairly low, whereas in the sheep fed urea food intakes rose over the final 6 weeks of the experiment. There was a significant linear regression of live-weight change on food intake only with the urea-fed sheep. Intakes of urea-N from the blocks were extremely variable between individual sheep and between periods within sheep; in most cases, however, they appeared to be adequate, as this type of supplementation gave results similar to those obtained by mixing urea throughout the roughage.There was no significant effect of urea on total wool growth during the experimental period, although wool growth in the supplemented shepp showed a rise towards the end of the experiment. Wool growth in any 4-weekly period was closely related to food intake and live-weight change during that period.

An evaluation of rhodamine-labeled lysozyme as a fluorescent stain for in situ soil bacteria

1972 ◽  
Vol 18 (6) ◽  
pp. 933-936 ◽  
Author(s):  
L. J. McElroy ◽  
L. E. Casida Jr.
Keyword(s):  
Fluorescence Microscopy ◽  
Soil Bacteria ◽  
Soil Microorganisms ◽  
Fluorescein Isothiocyanate ◽  
Soil Microflora ◽  
Light Diffraction ◽  
Enzyme Conjugate ◽  
Fluorescent Stain ◽  
Diffraction Microscopy

Rhodamine-labeled lysozyme, in conjunction with fluorescein isothiocyanate conjugated to gelatin as a counterstain, was evaluated as a fluorescent stain for resident soil microorganisms. Preparations were observed by light-diffraction microscopy, transmitted incandescent-light microscopy, and reflected ultraviolet-fluorescence microscopy using a modified light-diffraction microscope, and by conventional transmitted incandescent and ultraviolet-fluorescence microscopy. Laboratory-grown microbial cultures superimposed on the resident soil microflora, as well as the non-dormant resident soil microorganisms, usually fluoresced properly when the stain and counterstain were applied to soil, and the blocking test with non-conjugated lysozyme was effective. What were assumed to be semidormant cells fluoresced to a lesser degree, and the blocking test was only partially effective. In contrast, the dormant resident soil microorganisms usually did not become stained by the methods used. A possible explanation is that a peripheral structural component surrounding many of the resident dormant cells in soil may have rendered their cell-wall substrate inaccessible to the enzyme conjugate.

scholarly journals Evolution of nitrogen mineralization dynamics and bean production with three different organic amendments in the arid soil of south Tunisia

Italus Hortus ◽  
2021 ◽  
Vol 28 (1) ◽  
pp. 74
Author(s):  
Nissaf Karbout ◽  
Houda Beser ◽  
Latifa Dhaouidi ◽  
Mohamad Wahba ◽  
Mohamed Moussa
Keyword(s):  
Sewage Sludge ◽  
Organic Amendments ◽  
Soil Salinization ◽  
Physico Chemical ◽  
Bean Plants ◽  
Carbon Nitrogen Ratio ◽  
Nitrogen Ratio ◽  
One Year ◽  
Experimental Trials ◽  
The Impact

Although the importance of organic amendments on arid soils of semi-arid and arid lands in improving long-term soil fertility, the excessive use of these amendments may induce the mineralization of the soil’s native organic components. Thus, this study focused on the examination of the impact of the use of three different amendments, sewage sludge, compost, and horse manure on nitrogen soil dynamics as well on the physico-chemical characteristics (soil texture, nitrogen cycle, and carbon concentration) and plant characteristics (morphology and production). In this context, the present work discusses one of the major issues challenging sustainable agriculture development related to increasing land degradation, soil salinization, and fertility loss. The three amendments were applied on the soil collected at the Institute of Arid Regions of Gabes. The findings of these experimental trials indicated that compost seems to be the most valuable organic amendment that may be used for an adequate supply of nitrogen and optimal benefits for plant growth. The highest mineral nitrogen content was found in the treatment with sludge. The manure-based treatment had the highest carbon/nitrogen ratio (C/N=25). The effects of the amendments were well reflected in the growth and production of bean plants after one year from the amendment. An increase in biomass was observed in the amended pots. The highest increase in pods biomass was obtained in the pots amended with sewage sludge and vegetable compost followed by household manure treatment

scholarly journals Changes in Soil Microflora Following Application of Fungicides Dyrene and Maneb to Tropical Soils

1969 ◽  
Vol 58 (1) ◽  
pp. 78-86
Author(s):  
H. D. Dubey ◽  
Rita L. Rodríguez
Keyword(s):  
Chemical Treatment ◽  
Soil Microorganisms ◽  
Tropical Soils ◽  
Soil Microflora ◽  
Fungal Population ◽  
Quantitative Changes

Changes in soil microorganisms following applications of 2,4-dichloro- 6-(o-cloroaniline)-s-triazine (Dyrene) and manganese ethylene bisdithiocarbamate (Maneb) at 0, 60, 240, and 960 ppm to the acid lateritic Humatas clay and the alkaline fertile San Anton loam incubated at 23° ± 1°C were studied for 18 months in the laboratory. In general, bacterial numbers increased and actinomycetes and fungi decreased especially at higher concentrations of the chemicals. The bacterial increase disappeared at the 10-month count but persisted longer at the 960 ppm rate of Maneb. Bacteria seem to be the principal microorganisms responsible for degradation of these fungicides in the soil. Maneb caused qualitative as well as quantitative changes in the fungal population. Microorganisms in the two soils differed in their response to the chemical treatment. Inhibition of the microorganisms was offset by inoculation with fresh soil.

scholarly journals Potential of biochar after the biological activation by native soil microflora

2021 ◽  
Vol 26 (3) ◽  
pp. e2219
Author(s):  
Helena Dvorackova ◽  
Jaroslav Záhora ◽  
Lubica Pospíšilová ◽  
Vítězslav Vlček
Keyword(s):  
Dehydrogenase Activity ◽  
Soil Microorganisms ◽  
Mineral Fertilizer ◽  
Statistical Test ◽  
Soil Microflora ◽  
Mineral Fertilizers ◽  
Activated Biochar ◽  
Native Soil ◽  
Negative Effect ◽  
And Control

Objective. Dehydrogenase activity after the biological activation of biochar by the native soil microorganisms was studied. The main aim was to improve biochar properties by activation and make it more friendly for the soil microflora. Materials and methods. The activation was reached by aerating with the soil solution for two weeks. No special inoculum of microorganisms was applied. The following treatments in four replicates were prepared: conventional raw biochar (BR), activated biochar (BA), mineral fertilizer DAM 390 (NF), and control (C). A statistical test for comparing treatments means (Fisher p≤0.05; program STATISTICA 12.0; StatSoft software Inc., Tulsa, Oklahoma, USA) was used. Results. Statistically significant differences in the dehydrogenase activity between the treatments BR, BA, and C were found. Application of mineral fertilizers had a negative effect and increasing of nitrogen leaching was observed. Conclusions. Activating of biochar is suitable metods for impove soil biota conition compared with convention biochar.

scholarly journals Evaluation of Non-Conventional Biological and Molecular Parameters as Potential Indicators of Quality and Functionality of Urban Biosolids Used as Organic Amendments of Agricultural Soils

2020 ◽  
Vol 10 (2) ◽  
pp. 517 ◽  
Author(s):  
Miriam del Rocío Medina-Herrera ◽  
María de la Luz Xochilt Negrete-Rodríguez ◽  
José Luis Álvarez-Trejo ◽  
Midory Samaniego-Hernández ◽  
Leopoldo González-Cruz ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Microorganisms ◽  
Organic Amendment ◽  
Agricultural Soils ◽  
Organic Amendments ◽  
Biological Properties ◽  
Different Seasons ◽  
C And N ◽  
Two Indices ◽  
Enzymatic Machinery

Biosolids are waste from wastewater treatment and have a high content of organic matter and nutrients. In this study, not conventional physicochemical and biological properties of biosolids produced during different seasons of the year were evaluated. These properties are not considered in environmental regulations; however, they are of agronomic interest as indicators of quality and functionality in soils. Also, molecular analysis by Fourier-transform infrared (FTIR) was conducted, enzymatic analysis using the APIZYM® system was performed and two indices of functional and microbial diversity were established. The results showed that the biosolids had a high content of total organic carbon, total nitrogen, P, and K. FTIR analyses showed that chemical composition of biosolids was similar during all year. The C and N of microbial biomass demonstrated presence of active microorganisms, as well as a uniformity in its richness and abundance of species that could present a positive synergy with soil microorganisms. The enzymatic activities showed that the biosolids contained an enzymatic machinery available to promote the mineralisation of the organic matter of biosolids and could even transcend into the soil. Finally, biological properties can be used as indicators of quality and functionality of biosolids before being used as an organic amendment, especially in agricultural soils.

EFFECT OF FOLIAR TREATMENT OF VEGETATIVE PLANTS ON SOIL MICROBIAL FLORA

1970 ◽  
pp. 19-23
Author(s):  
N. V. Fomicheva ◽  
G. Yu. Rabinovich ◽  
Yu. D. Smirnova
Keyword(s):  
Soil Microorganisms ◽  
Peat Soil ◽  
Analysis Data ◽  
Soil Microflora ◽  
Small Scale ◽  
Active Principle ◽  
Nitrogenous Compounds ◽  
Soil Microbial ◽  
Foliar Treatment ◽  
Positive Effect

The article contains materials of scientific research reflecting the positive effect on the soil microflora of foliar treatment of vegetative plants with various preparations. A small-scale experiment on growing carrots on low-lying peat soil of the Yakhroma floodplain (Moscow region) was carried out. For foliar treatments were applied biological means, developed at VNIIMZ – biological product LPB (the active principle – agronomically useful microflora) and biological means BoHum (the active principle – humic substances). Spraying was carried out three times per season at a rate of flow of a working solution of 300 l / ha (dilution 1: 100, 1: 300, 1: 500). To assess the effect of biological means on soil processes in soil samples, the number of ammonifying, amylolytic and phosphate-mobilizing microorganisms was determined. The intensity of the mineralization processes in the soil was estimated from the value of the mineralization coefficient. It was established that the foliar treatment of vegetative plants carrot with biological means of LPB and BoHum increased the total number of identified soil microorganisms by 21-22%, while the mineralization of nitrogenous compounds in the soil during spraying with humic bio means occurred more intensively 3 times, and the biologic preparation of LPB 2.3 times, concerning the control. Activation of soil-microbiological processes (due to bio means entering the soil), together with the activation of physiological processes of plant growth and development (as a result of contact with bio means on the leaf plate of plants) increased carrot yield by 19.4 and 18.3%, respectively, when using LPB and BoHum in 1: 300 dilutions. The regression analysis data confirmed a statistically significant relationship between carrot yield and the total number of soil microorganisms (r = 0.67) and soil mineralization coefficient (r = 0.77). The positive effect of foliar treatments on the soil microflora was also revealed in the cultivation of spring wheat and potatoes.

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