Activity Of Soil Microorganisms Research Articles

Paraná basin basalt powder: A multinutrient soil amendment for enhancing soil chemistry and microbiology

This study evaluated the effects of Paraná Basin basalt powder, a mining byproduct from southern Brazil, on the macro- and micronutrient content of two soil types, Oxisol (OX) and Typic Quartzipsamment (TQ), as well as the metabolic activity of soil microorganisms. Basalt powder doses were determined based on CaO levels required to correct Ca2+ levels in each soil, ranging from 0 to 4 times the recommended amount. Soil samples were collected for analysis after 60 and 170 days of incubation to assess soil attributes. Additionally, a laboratory study examined soil basal respiration (SBR) after 168 days of greenhouse incubation. The results revealed that higher doses of basalt powder application led to increased pH, P, K+, Ca2+, Mg2+, Cu, B, and Si levels in OX, while decreasing Al3+ levels in the same soil. In TQ soils, the effects were more limited, showing specific increases in pH, P, S–SO42-, and Si levels. Moreover, there was a 21% increase in SBR in OX with higher basalt rates. These findings suggest that basalt powder has the potential to serve as an environmentally friendly solution for soil fertilization, positively impacting its chemical and biological properties.

Understanding and exploring the diversity of soil microorganisms in tea (Camellia sinensis) gardens: toward sustainable tea production.

Leaves of Camellia sinensis plants are used to produce tea, one of the most consumed beverages worldwide, containing a wide variety of bioactive compounds that help to promote human health. Tea cultivation is economically important, and its sustainable production can have significant consequences in providing agricultural opportunities and lowering extreme poverty. Soil parameters are well known to affect the quality of the resultant leaves and consequently, the understanding of the diversity and functions of soil microorganisms in tea gardens will provide insight to harnessing soil microbial communities to improve tea yield and quality. Current analyses indicate that tea garden soils possess a rich composition of diverse microorganisms (bacteria and fungi) of which the bacterial Proteobacteria, Actinobacteria, Acidobacteria, Firmicutes and Chloroflexi and fungal Ascomycota, Basidiomycota, Glomeromycota are the prominent groups. When optimized, these microbes' function in keeping garden soil ecosystems balanced by acting on nutrient cycling processes, biofertilizers, biocontrol of pests and pathogens, and bioremediation of persistent organic chemicals. Here, we summarize research on the activities of (tea garden) soil microorganisms as biofertilizers, biological control agents and as bioremediators to improve soil health and consequently, tea yield and quality, focusing mainly on bacterial and fungal members. Recent advances in molecular techniques that characterize the diverse microorganisms in tea gardens are examined. In terms of viruses there is a paucity of information regarding any beneficial functions of soil viruses in tea gardens, although in some instances insect pathogenic viruses have been used to control tea pests. The potential of soil microorganisms is reported here, as well as recent techniques used to study microbial diversity and their genetic manipulation, aimed at improving the yield and quality of tea plants for sustainable production.

Soil microbial functional diversity is primarily affected by soil nitrogen, salinity and alkalinity in wetland ecosystem

Wetland ecosystems, recognized as important carbon sinks, face challenges due to climate change. Although wetland soil microorganisms play a major role in the wetland carbon cycle, the mechanisms influencing their spatial distribution remain elusive. Here, we investigate the impact of soil properties on the spatial distribution of soil microorganisms across five saline-alkali wetlands (Xianghai [XH], Niuxintaobao [NX], Momoge [MMG], Zhalong [ZL], and Halahai [HLH]) within the Songnen Plain, China. We utilized the Biolog-ECO method to assess the carbon metabolic activity, microbial diversity, and carbon source utilization preference of soil microorganisms. Using the structural equation model, we analyzed factors influencing microbial carbon metabolic activity and microbial diversity. Results indicate that southern wetlands harbor soil microbial communities exhibiting higher carbon metabolic activity, Shannon index, and substrate richness, compared to their northern counterparts. Specifically, soil microorganisms in NX and XH wetlands demonstrate a preference for labile organic carbon, whereas those in HLH and ZL wetlands preferred to use recalcitrant carbon. Furthermore, soil microbial carbon metabolic activity is primarily regulated by soil total nitrogen content, whereas soil microbial diversity is primarily regulated by soil salinity and alkalinity. Our findings revealed the distribution characteristics and influencing factors of soil microorganisms in the Songnen Plain wetland, contributing to understanding the maintenance mechanism of wetland carbon sink function.

Differential response patterns of soil fungal and bacterial communities to typical vegetation types in the Yellow River floodplain ecosystem

Soil microorganisms are one of the primary driving factors of biogeochemical cycles in floodplain ecosystems. Vegetation type has an impact on the activities of soil microorganisms. However, it is currently unclear whether the composition and structure of soil bacterial and fungal communities in floodplain ecosystems have a consistent response pattern to vegetation communities. In this research, Illumina Mi-Seq sequencing technology was employed to study the soil fungal and bacterial communities covered by three typical vegetation communities in the Yellow River floodplain ecosystem. Our results showed that the underground biomass, total carbon (TC) and nitrogen (TN) were significantly different between the three vegetation communities. In the surface soil of summer, the Shannon index of fungi community was the highest in Tamarix chinensis (T. chinensis) and the lowest in Phragmites australis (P.australis). In autumn, the Shannon and Simpson indices of bacterial communities in surface soil were the highest in the P.australis and the lowest in the Sonchus arvensis (S.arvensis), but there was no significant difference in the β-diversity of bacterial community among the three vegetation communities. In autumn, the Chao1 index of fungal community in subsoil was the highest in P.australis and the lowest in S.arvensis, while there was no significant difference in the α-diversity of bacterial community among the three vegetation communities. In addition, there were considerable disparities in the fungal and bacteria community structure in various vegetation soils. Redundancy analysis (RDA analysis) showed that TN, TC, AP, pH, NO3 -, NH4 + and moisture content were key factors driving bacterial community structure, while TP, NH4 +, pH and moisture content were essential factors driving fungal community composition. These outcomes help to improve our understanding of the ecological model of soil fungal and bacterial community in floodplain ecosystems and give assistance in improving the role of an ecological barrier and floodplain service possibilities.

Metagenomic analysis of soil forest microbiota on Mount Ungaran, Central Java, Indonesia

The ecological functions of forest soils are largely determined by the activities of soil microorganisms. This study aims to analyze the diversity and abundance of microbes in forest soil on Mount Ungaran, Ngesrepbalong Village, Kendal Regency, Central Java, Indonesia. This study used an exploratory observation method. Five hundred grams of forest soil was collected aseptically for chemical and metagenomic analysis. Metagenomic analysis was carried out based on 16S rRNA gene markers V3-V4 region. The result showing that the forest soil was dominated by bacteria of the order Rhizobiales (13.17%), Thermincolales (9.29%), and Vicinamibacterales (6.95%), as well as archaea of the order Nitrososphaerales (62.89%), Nitrosotaleales (4.61%), and Nitrosopumilales (1.67%). At the genera level, forest soil was dominated by Thermincola (8.42%) and Bacillus (7.39%), and one genera of archaea, namely Nitrososphaeraceae (23.17%). The bacteria that dominate forest soil are a group of Plant Growth Promoting Bacterial Agents (PGPB) in the nitrification process. Meanwhile, archaea that dominate forest soil act as ammonia oxidizing agents (AOA).

Impacts of biostimulants on crop yield and biological activity under drought conditions

AbstractIntroductionBiostimulants are proposed to have a role in sustainable food production and are being increasingly used strategies to limit the negative effects of drought stress on crop yield and soil health. However, how different biostimulants used alone, or in combination with conventional management approaches affect soil health and crop yield under drought in different soils is not well understood. Here we conducted a glasshouse experiment to investigate this.Materials and MethodsTwo soil types from fields maintained under intensive (IM) and extensive (EM) management practices were used with two commercial biostimulants [Universal Natural Plant food (UNP) and Converte Seed Primer (CSP)] on soil microbial populations and crop yield (lettuce) under well‐watered and drought stressed conditions. We examined the activity and biomass of soil microorganisms as well as seed germination and root and shoot biomass to examine the effect of application of biostimulants on parameters of soil health and crop yield.ResultsBiostimulants generally increased crop yield, basal soil respiration and microbial biomass, with effects stronger in EM soils than in IM soils, but effects on soil enzyme activities were variable. The combined use of biostimulant and inorganic fertiliser negated the benefits of the biostimulant on soil biological properties in some cases. Nevertheless, effects of biostimulants had a positive impact on crop yield with the combined use of soil‐applied and seed applied biostimulants have the greatest impact on plant biomass and also conferring some resistance in both soil microbial communities and plant growth to drought.ConclusionsWhile biomass and activity of the microbial community and plant growth responses to biostimulant additions are both soil and biostimulant dependent, their combined use has potential to aid both plants and maintain promote microbial activity under of drought, compared to conventional fertiliser treatments in extensively managed soils.

Populasi Bakteri Penambat N2 Atmosfer pada Tanah Sawah yang Diberikan Herbisida dengan Berbagai Kandungan Bahan Aktif

Supporting the increase in agricultural production today cannot be separated from the use of herbicides in land preparation activities. Most of the herbicides applied to plants will eventually fall to the ground, then undergo changes and in a certain time will be absorbed by the clay fraction and organic matter in the soil, which is generally known as herbicide residue. Toxic herbicide residues in the soil can kill soil microbes, which are not actually the target (non-target microorganisms) so that they interfere with the activity of soil microorganisms which in turn can affect the nutrient cycle in the soil.This research was conducted with the aim of knowing the effect of giving herbicides with various types of active ingredients in paddy fields on the viability of N-fixing bacteria and their relationship to soil chemical properties.The research and analysis was carried out from November 2021 to January 2022. The method used in this study was the Completely Randomized Design (CRD) environmental design method with a single factor treatment design, namely the type of herbicide active ingredient. Based on the results of research that has been carried out, it is known that the herbicide Glyphosate can increase the population of atmospheric N2-fixing bacteria in the soil, while the herbicide Paraquat and Methyl Metsulfuron can suppress the population growth of atmospheric N2-fixing bacteria

Functional diversity of microbial communities in herbaceous vegetation patches in coal mine heaps

AbstractCoal mine heaps represent unique novel environments, suitable for studying plant succession and its influence on the activity of microbes inhabiting the rhizosphere. Our aim was to verify if the functional diversity and catabolic activity of soil microorganisms would increase along with the plant succession from non‐vegetated and forbs‐dominated to grass‐dominated communities. The study was conducted on coal mine heaps located in Upper Silesia (Southern Poland), focusing on non‐vegetated patches, patches dominated by forbs–Tussilago farfara and Daucus carota (in the early stages of succession), and by grasses–Poa compressa and Calamagrostis epigejos (in later stages of primary succession). The catabolic activity and functional diversity of soil microbial communities were analyzed based on community‐level physiological profiles using BIOLOG EcoPlatesTM and the activity of dehydrogenase, alkaline phosphatase, acid phosphatase, and urease. Our results showed that spontaneous vegetation on coal mine heaps strongly affects the physicochemistry of the substrate and the functional diversity of soil microbial communities. Grasses' rhizosphere was hosting more active and functional diversified microbial communities, while non‐vegetated and T. farfara‐vegetated patches were accompanied by a reduced development of soil microbiota. Furthermore, grasses were mainly associated with a substantial delivery of plant litter to the substrate, providing a source of carbon for microorganisms.

Spatial relationship of landform surface features and biocrusts, and their effect on soil microbial biomass on an alluvial fan

AbstractThe spatial cover of biocrusts represents a suitable habitat for the activity of soil microorganisms in semi‐arid and arid regions. Microorganisms are one of the essential components of soil quality. Therefore, it is necessary to understand the processes of biocrust habitat formation in landforms and their mutual relationship with soil properties. We studied the spatial distribution of biocrusts and their effect on soil microbial biomass and carbon activity in a semi‐arid alluvial fan in NE Iran. A total of 72 soil samples (using plots 0.25 m2) from the topsoil layers (0–5 cm) were collected along the alluvial fan in September 2020. Soil surface properties and microbial biomass in two categories of biocrust and non‐biocrust were investigated in three classes of biocrusts coverage obtained by geostatistics. Our results revealed that biocrusts had a negative correlation with gravel coverage and elevation; in contrast, the suitable spaces for biocrusts growth were created by cobble clasts. The biocrusts have provided favourable conditions for soil microorganisms by altering the properties of the soil (such as increasing organic carbon, nitrogen and available phosphorus and decreasing pH), and thus they increased basal soil respiration and microbial biomass. Different microbial activities were led by the predominant type of biocrusts, as the chlorolichen crusts had the most significant effect on increasing the microbial biomass phosphorus while cyanolichen crusts increased the microbial biomass carbon. Moss and cyanolichen crusts increased microbial activity and respiration more than cyanobacteria crusts. Therefore, the soil quality has improved by biocrusts in semi‐arid ecosystems.

THE DETERMINATION OF THE MOST OPTIMAL METHODS FOR THE IRRIGATION OF CROPS ON DIFFERENT SOIL TYPES

Climate change due to multiple pollution problems (forest clearing, overgrazing, motor vehicle emissions, construction expansion, etc.), has led to increased global average temperature and reduced rainfall. Under these conditions, the mineralization of organic matter is intensified, the activity of soil microorganisms is reduced and implicitly decreases soil trophicity. These aspects further show the need to apply irrigation in the agricultural sector, rationalysing water, managing it and recommending the best methods of water distribution, on soils with different textural classes. In this regard, research was carried out on water permeability, on soils formed in different pedo-climatic conditions. Thus, three soil profiles were opened, in the Tecuci Plain, on a typical arenosoil, in the Dobrogea Plateau, on a calcaric chernozem and in the Gavanu-Burdea Plain on a chromic luvisol. Soil profiles were characterized morphologically and physico-chemically, soil samples were collected both in natural and modified settlement (metal cylinders). The physico-chemical analyses for the three soil types were determined within INCDPA laboratories Bucharest. Based on soil samples collected in metal cylinders, water permeability was determined using the ratio between the thickness of the soil horizon and the time of water infiltration. Depending on the permeability of the soil on the three different soil types, the most suitable and economical watering methods for the current climatic conditions have been established and recommended.

Long-Term Monitoring Studies of the Mycorrhizal Colonization of Aesculus hippocastanum L. Roots and the Vitality of Soil Microorganisms in Urban and Non-Urban Environments

Stress factors typical in urban environments adversely affect the productivity and vigor of trees and may limit the development of tree roots with associated soil fungi and bacteria. Studies on mycorrhizal symbiosis and the activity of soil microorganisms are important in monitoring the adaptation of trees to urban conditions. We compared the symbiotic activity of arbuscular mycorrhizal fungi (AMF) living in the rhizosphere of mature white chestnut trees (Aesculus hippocastanum L.) in an urban ecosystem at sites with varying degrees of anthropopressure and in a rural area. We used two methods: (1) direct analysis of the root samples, (2) assessment of the colonization of trap plants grown in the soil taken from under selected white horse chestnut trees. The seasonality of mycorrhizal colonization and soil microbial respiration based on the enzyme activity of nonspecific dehydrogenase (DHA) was studied over several growing seasons. The concentrations of macronutrients in the soil from all study sites were in the ranges accepted as normal for the upper soil layer. However, the C/N ratio indicated carbon limitation in the soil at urban and rural study sites. The results showed that arbuscular mycorrhizal fungi indigenous in the rhizosphere of A. hippocastanum developed a functioning mycorrhizal symbiosis at all research sites, including at highly disturbed urban locations, and that the mycorrhizal colonization varied between the study sites and the research term. The trap culture method confirmed the high biological potential of the soil microbial community, including AMF in urban ecosystems, which was comparable to that at the reference site in the rural environment. Soil moisture strongly affected the overall soil microbial vitality. This research showed that the mycorrhizal status of A. hippocastanum is more strongly influenced by climatic conditions and seasonal rhythms of trees than by urban/non-urban locations.

Rock Powder Enhances Soil Nutrition and Coffee Quality in Agroforestry Systems

The use of rock powders is an agricultural practice that facilitates the agroecological transition and autonomy of many farmers. These inputs should be used in conjunction with management systems that enhance the weathering of the minerals contained in the rocks. This study aimed to assess the impact of incorporating gneiss powder on soil quality and coffee cultivation within agroecological and organic frameworks, encompassing agroforestry systems (AFSs) as well as areas fully exposed to sunlight (FS). Comprehensive analyses, including chemical, microbiological, and physical assessments, were carried out on the soil. The study involved evaluating various parameters such as electrical conductivity, grain density, total titratable acidity, and pH of the exudates to gauge the coffee quality. Following a 24-month application of rock powder, noteworthy observations included increased soil moisture in agroforestry systems (AFSs), presumably attributable to enhanced nutrient availability (potassium, calcium, magnesium, copper, and zinc) derived from the gneiss powder. In addition, a higher level of CO2 was derived from microbial respiration than from soil production. Similarly, coffee beans presented lower electrical conductivity, higher density, and fewer defects in AFSs than fully exposed sun systems (FS). The total titratable acidity values remain consistent with the limits indicated in the literature for quality coffees; the pH values, however, were lower. The results suggest that the use of gneiss powder enhances soil microorganism activity and accelerates the biological weathering of minerals for coffee plantations in AFSs.

Long-term effects of oil contamination on soil quality and metabolic function.

Widespread soil contamination with oil and the toxicity of petroleum hydrocarbons to soil biota make it extremely important to study microbial responses to oil stress. Soil metabolites reflect the main metabolic pathways in the soil microbial community. The examination of changes in the soil metabolic profile and metabolic function is essential for a better understanding of the nature of the pollution and restoration of the disturbed soils. The present study aimed to assess the long-term effect of oil on the ecological state of the soil, evaluate quantitative and qualitative differences in metabolite composition between soil contaminated with oil and non-contaminated soil, and reveal biologically active metabolites that are related to oil contamination and can be used for contamination assessment. A long-term field experiment was conducted to examine the effects of various oil concentrations on the biochemical properties and metabolic profile of the soil. Podzolic soil contaminated with oil demonstrated the long-term inhibition of soil biological activity and vegetation. Oil affected the metabolic activity of soil fungi increasing the production of toxic metabolites. A metabolomic approach was employed to determine soil metabolites. The metabolite profile was found to vary greatly between oil-contaminated and non-contaminated soils. Carbohydrates had the largest number of metabolites negatively affected by oil, while the content of organic acids, phenolic compounds, and terpenoids was mainly increased in oil-contaminated soil. The evaluation of the long-term impact of oil on microbial metabolism can make a valuable contribution to the assessment of soil quality and the activity of soil microorganisms being under stress from oil pollution. The results contribute to a further understanding of the role of microorganisms in the ecological functions of contaminated soil, which can be useful in the development of rehabilitation strategies for disturbed sites.

Effects of Organic and Inorganic Fertilizer on the Population Dynamics of Soil Microorganisms in Tea Rhizosphere at Kericho, Kenya

Aim: The long-term cultivation of tea (Camellia sinensis L.) alters microorganism communities in the rhizosphere; it can increase saprotrophs, pathogenic microorganisms and reduce symbiotrophs. Fertilizers are sources of plant essential nutrients and can influence the activity and population of soil microorganisms. This study aimed to determine the effect of fertilization regimes on the population dynamics of soil microorganisms in the tea rhizosphere for its management.
 Place and Duration: The study was carried out at the Tea Research Institute, Kericho, Kenya during the dry (February-March) and wet season (June-July).
 Methodology: Two main fertilizer types; organic (Phymix) and inorganic (Nitrogen, Phosphorus and Potassium- NPK) and foliar fertilizer (Tecamin Max, Tecnokel Amino Mix) as sub treatments application at the rate of 0, 75 and 150 kg N ha-1), were applied in four replications. Sampling of soil was done before treatment application, during the dry season (February-March) and the wet season (June-July). The fungal and bacterial populations for both seasons were characterized. The data collected was analyzed using SAS (version 9) Statistical Software.
 Results: The study showed that the fungal colony units varied significantly (P≤0.05) between the types of fertilizer both during dry and rainy season. The interactions of fertilizer type and rate also varied significantly (P≤0.05) for fungal populations during both seasons. No significant variation was noted for the bacterial population (cfu) for both seasons regardless of fertilizer type and rates. The fungi identified included; Cylindrocarpon spp., Trichoderma spp., Penicillium spp., Aspergillus spp. Colletotrichum spp., Pestalotiopsis spp., and Fusarium spp. The bacteria included; Pseudomonas spp., Bacillus spp., Rhizobium spp., and Xanthomonas spp.
 Conclusion: Organic fertilizer increased fungal populations significantly, an indication of enhanced soil health and may be recommended for use.

Effects of repeated afidopyropen treatment on the structure and function of the soil microbial community

Chemical insecticides are the most effective pest control agents. Afidopyropen is a novel insecticide used against sap-sucking insects, such as aphids. However, the effects of repeated afidopyropen application on the structure and function of soil microorganisms remain unknown. In this study, the changes in the enzyme activities, community structure and function, and relative abundance of antibiotic resistance ontology (ARO) of soil microorganisms were investigated during three repeated afidopyropen applications under laboratory conditions at the maximum recommended dosage (M1) and 10 times the M1 (M10). The neutral phosphatase (NPA) and catalase (CAT) activities in the soil were significantly suppressed after afidopyropen treatment. The Simpson diversity index (1/D) and Shannon–Wiener diversity index (H) also decreased in both the M1 and M10 afidopyropen-treated soils, indicating a remarkable decrease in soil microorganism diversity. The average well color development (AWCD) first increased and subsequently recovered to normal levels after the third application of the insecticide, suggesting that afidopyropen application could increase the metabolic activity of soil microorganisms. Metagenomic analysis showed that repeated afidopyropen application in both the M1 and M10 treatment groups altered the community structure of soil microorganisms, albeit in different ways. Furthermore, repeated afidopyropen application significantly increased the relative ARO abundance, especially in the M10 treatment, with the most dominant AROs being adeF, baeS, and IND-6. These findings reveal the effects of excessive afidopyropen application on soil microorganisms and lay an important foundation for the comprehensive evaluation of the impact of this insecticide on the environment.

Siliceous Rocks in the Fertilizer System of Agricultural Crops

Over the past 25 years, the influence of siliceous rocks (diatomite, zeolite, flask) on soil properties (typical chernozem, leached chernozem), yield and quality of agricultural crops (cereals, potatoes and vegetables, technical) when used both in pure form and together with mineral fertilizers and bird droppings has been studied. The possibility of creating new types of more effective fertilizers based on siliceous rocks by enriching them with elements or compounds (in particular amino acids) that most fully meet the requirements of crops has been studied. Studies have shown that the yield of grain crops when using diatomite as a fertilizer is little inferior to mineral fertilizers. Thus, the increase in grain yield of winter wheat on average over all the years of research reached 0.60–1.30, spring wheat – 0.15–0.67, barley – 0.50–0.93 t/ha. The increase in corn grain yield, depending on the dose of zeolite application, ranged from 0.93 (dose of 500 kg/ha) to 1.36 (dose of 2000 kg/ha) t/ha. Potatoes and vegetables (cucumbers, tomatoes, carrots, table beets), as well as industrial crops (sugar beet, sunflower) are highly responsive to the use of siliceous products as fertilizers. In particular, the yield of sugar beet root crops increased by 6.5 t/ha on average when diatomite was applied at a dose of 3 t/ha, and in some years – up to 8.6 t/ha. The increase in crop yield increased very significantly when combined with nitrogen fertilizers from N30 to N60 – by 11.3 and 12.5 t/ha. The high efficiency of silicon-containing rocks as fertilizers of agricultural crops is due to their complex influence on the fundamental properties of the soil: physical (structural condition, soil density, structure of the arable layer), biological (activity of soil microorganisms), chemical (nutritional regime, environmental safety), as well as on the protective properties of plants.

Bentonite Impact on Soil Properties and Biological Activity in the Face of Drought : A Review

The clay mineral bentonite has received a lot of attention for its potential to reduce the harmful effects of drought on soil health and biological activity. Reduced enzymatic activity and microbial diversity are two negative outcomes of the drought’s impact on soil quality. Bentonite, however, has been shown to aid in the restoration of biological functions in drought-affected soils. Bentonite’s function as a soil moisture retainer is an important consideration. Bentonite acts as a reservoir, trapping water within its layers due to its high water-holding capacity and ability to form a gel-like structure. This capacity for water retention can reduce the negative impact of drought on soil organisms, making conditions better for enzyme activity and microbial life. Bentonite has also been shown to increase soil enzyme production and activity. Soil fertility and healthy ecosystems rely on the work of enzymes in nutrient cycling and organic matter decomposition. Reduced enzymatic activity is a common consequence of drought stress, which in turn reduces nutrient availability and worsens soil health. The application of bentonite, however, has been shown to increase enzyme production and activity even in drought conditions. This has the potential to improve soil health and productivity by preserving vital soil processes and encouraging nutrient cycling. In addition, bentonite can increase soil microorganism activity in dry areas. Soil microorganisms play a crucial role in the cycling of nutrients, the control of disease, and the health of the soil ecosystem as a whole. Reduced microbial diversity and activity have been linked to drought stress. However, research shows that applying bentonite to drought-affected soils increases both microbial growth and diversity. Increased nutrient availability, enhanced soil structure, and enhanced water infiltration and retention are all possible results of microbial stimulation. In conclusion, areas that have experienced drought can benefit from bentonite’s ability to improve soil enzymes and biological activity. Bentonite helps restore and maintain soil health even when water supplies are low. It does this by increasing water retention, encouraging enzyme production, and boosting microbial activity. To fully realize bentonite’s potential for fostering sustainable agriculture and sustaining healthy ecosystems, more study is required to determine the optimum application rates and methods.

Improving mango production using partial root drying technique and organic fertilisation: Field and modeling study

ABSTRACT The decreasing in water availability due to climate change can affect agricultural production. The water shortage problem led to the development of several water saving techniques. One of the waters saving techniques in irrigation is the partial root-zone drying (PRD) method. Tow field experiments accompanied by a modeling study were carried out during seasons 2020/2021 and 2021/2022, respectively, using four deficit irrigation strategies [FI (100% of full irrigation), DI1 (0.75FI), DI2 (0.5FI) where water was supplied to both sides of the mango trees and DI3 (Partial Root-zone Drying, PRD = 0.5FI) where water was supplied to a single side of each tree in an alternating manner)]. The four irrigation methods were designated as the study’s major plots. Then, for the purpose of adding compost, each main plot was divided into four smaller plots [NC (No-Compost), C12 (12 ton ha−1), C18 (18 ton ha−1) and C24 (24 ton ha−1)] to investigate the effects of such treatments on increasing water productivity, yield, and the quality of mango fruits. The results indicated that adding compost with PRD irrigation method decreased water stress throughout the root zone and increased the yield, water productivity and fruit quality. Compost addition C24 (24 ton ha−1) with PRD irrigation increased the amount of soil organic matter and microorganism activity when compared to other treatments. Additionally, C24 treatment improved mango quality under both FI and PRD treatments, the PRD technique enhanced fruit yields by 3.8% and 7.3% and water productivity by 51.6% and 53.8% for 2021 and 2022 seasons, respectively, compared to FI, while reducing the applied irrigation water by 50% for each season. In comparison to other irrigation strategies, the PRD strategy had shown superior outcomes in enhancing the yield, water productivity, and quality of mango yield. With the use of compost “C24” as organic matter fertilizer, PRD proved to be an effective dual technique to save water and increase productivity. Under both current and future water scarcity caused by climate change, it could be a successful adaptation technique. The SALTMED model produced accurate simulations of the soil moisture content, mango production, and water productivity during the two seasons.

ORGANIC FERTILIZER'S ROLE IN THE IMPROVEMENT OF SOIL MICROFLORA AND BIOMETRIC VALUES IN FRUIT CROPS

Intensive farming has adversely affected soil fertility and ecosystems due to excessive chemicalization in the Kazakhstan Republic. The soil lacks organic matter, leading to declining fertility. Biologization has emerged to address this issue as a solution to improve soil fertility and enhance the growth and development of crop plants. This study aimed to determine the impact of organic fertilizers on the composition of soil microflora and biometric values in cultivating stone and pome fruits. The use of microbiological methods analyzed soil microflora and physiological bacterial groups. The research’s novelty lies in developing a technology that utilizes organic fertilizers and biological products to improve the activities of soil microorganisms and plant roots’ nutrition. Organic fertilizers ‘Bio juice Energy Plus’ and ‘Agroflorin’ positively influenced beneficial bacteria and fungi and significantly contributed to soil enrichment. Organic fertilizers and biological products support soil biological processes and replenish the nutrients, promoting sustainable agricultural productivity and reducing chemical dependency. The current study emphasizes the potential of organic fertilizers and natural products in enhancing soil fertility and supporting plant growth in Kazakhstan. Biologization also offers an eco-friendly approach to agricultural practices, ensuring agronomic productivity and the long-term good health of soils.

Potential Secretory Transporters and Biosynthetic Precursors of Biological Nitrification Inhibitor 1,9-Decanediol in Rice as Revealed by Transcriptome and Metabolome Analyses

Biological nitrification inhibitors (BNIs) are released from plant roots and inhibit the nitrification activity of microorganisms in soils, reducing NO3‒ leaching and N2O emissions, and increasing nitrogen- use efficiency (NUE). Several recent studies have focused on the identification of new BNIs, yet little is known about the genetic loci that govern their biosynthesis and secretion. We applied a combined transcriptomic and metabolomic analysis to investigate possible biosynthetic pathways and transporters involved in the biosynthesis and release of BNI 1,9-decanediol (1,9-D), which was previously identified in rice root exudates. Our results linked four fatty acids, icosapentaenoic acid, linoleate, norlinolenic acid, and polyhydroxy-α,ω-divarboxylic acid, with 1,9-D biosynthesis and three transporter families, namely the ATP-binding cassette protein family, the multidrug and toxic compound extrusion family, and the major facilitator superfamily, with 1,9-D release from roots into the soil medium. Our finding provided candidates for further work on the genes implicated in the biosynthesis and secretion of 1,9-D and pinpoint genetic loci for crop breeding to improve NUE by enhancing 1,9-D secretion, with the potential to reduce NO3‒ leaching and N2O emissions from agricultural soils.