Fungal Populations Research Articles

Bioremediation alternatives for total petroleum hydrocarbon removal in agricultural soil

Objective: The purpose of the present study is to highlight the importance of assessing bioremediation and total petroleum hydrocarbon removal by bioaugmentation and biostimulation on the rhizosphere. Design/methodology/approach: An 89-day experiment was established with treatments considering plant (corn) establishment–crude petroleum (25,000 mg kg-1)–bacteria and hydrocarbonoclastic fungi–adding nitrogen and phosphorus to agricultural soil. At the end of the experiment, hydrocarbonoclastic fungal and bacterial populations and total petroleum hydrocarbon removal were assessed. Results: Both microbial groups increased in number and time. The treatment with 120 kg nitrogen ha-1 and 12.5 kg phosphorus ha-1 allowed the highest population (227 x 103 g-1 of colony forming units (CFU) of hydrocarbonoclastic bacteria). A total of 83% petroleum hydrocarbon removal was obtained as established in 89 days. Limitations on study/implications: The effectiveness of bioremediation can vary significantly in real environments due to factors, such as soil variability, climate. Findings/conclusions: The previous results highlight the importance of using these bioremediation techniques to eliminate hydrocarbons in contaminated agricultural soils.

Multifunctional particle additives for simultaneous enhancement of toughness and biodegradation of poly(lactic acid)

A multifunctional biodegradable additive powder has been created for simultaneous enhancement of toughness and compostability of the biopolymer poly(lactic acid) (PLA). PLA has promising strength and stiffness compared to commodity plastics, but the neat polymer is not a direct replacement for petroleum-based plastics in consumer products due to its brittle fracture and low ductility. Although officially certified as biodegradable, PLA suffers from a slow composting rate and is not considered compostable outside of specialized environments such as those found in industrial composters (where temperatures approaching 60 °C are used). A powder-based additive has been developed that increases both the elongation at break and the composting rate of PLA to enhance the attractiveness of PLA over current commodity plastics. In this study, various amounts of the additive are compounded into PLA using a single screw extruder. Test specimens are prepared using the additive manufacturing method of fused filament fabrication. The PLA-based composites show a minimal loss of strength and stiffness as compared to plasticized PLA resins, and the additives provide tunable properties to the material in the ability to control elongation versus strength and stiffness. Direct tensile testing of 3.75 mm filament for additive manufacturing to compare material properties is also investigated. The composting behavior is investigated using specimens made by extrusion as part of an additive manufacturing model system. Composting studies show an increase in composting rate under elevated temperature of 58 °C and 50 % relative humidity under modified ASTM D5338 soil contact testing. Microbial analysis indicates that the additive particles support the growth of specific degraders and shifts the composition of the microbial population of bacteria and fungi and has potential for enhancing the compostability in home compost.

Plants interfere with non-self recognition of a phytopathogenic fungus via proline accumulation to facilitate mycovirus transmission

Non-self recognition is a fundamental aspect of life, serving as a crucial mechanism for mitigating proliferation of molecular parasites within fungal populations. However, studies investigating the potential interference of plants with fungal non-self recognition mechanisms are limited. Here, we demonstrate a pronounced increase in the efficiency of horizontal mycovirus transmission between vegetatively incompatible Sclerotinia sclerotiorum strains in planta as compared to in vitro. This increased efficiency is associated with elevated proline concentration in plants following S. sclerotiorum infection. This surge in proline levels attenuates the non-self recognition reaction among fungi by inhibition of cell death, thereby facilitating mycovirus transmission. Furthermore, our field experiments reveal that the combined deployment of hypovirulent S. sclerotiorum strains harboring hypovirulence-associated mycoviruses (HAVs) together with exogenous proline confers substantial protection to oilseed rape plants against virulent S. sclerotiorum. This unprecedented discovery illuminates a novel pathway by which plants can counteract S. sclerotiorum infection, leveraging the weakening of fungal non-self recognition and promotion of HAVs spread. These promising insights provide an avenue to explore for developing innovative biological control strategies aimed at mitigating fungal diseases in plants by enhancing the efficacy of horizontal HAV transmission.

Speleomycological and chemical assessment of sediments in Demänovská Slobody Cave (Slovakia)

Our study unveils the complex interplay between fungal diversity and geochemical environments within the Demänovská Slobody Cave, marking the first comprehensive speleomycological and chemical investigation of its kind. Through meticulous analysis using both microscopic techniques and ITS region gene barcoding, we recorded 17 fungal species, including four previously unrecorded in subterranean settings (Cladosporium ramotenellum, Porostereum spadiceum, Rhexocercosporidium carotae, and Trichocladium nigrospermum), with Porostereum spadiceum as the most prevalent. These findings illuminate the crucial role of fungi in subterranean biogeochemical cycles, demonstrating how nutrient levels and pH significantly influence fungal populations. Namely, the levels of mineral nutrients (N, P, K, Mg, Ca) and organic matter in sediments within the cave were lower than in soil those outside it. Conversely, the pH values of the tested samples inside the cave were higher compared to those outside. Positive correlations were observed between the average number of fungi and the content of N, P, K, CO, and organic matter (p < 0.05). Conversely, the concentration of fungi decreased with increasing levels of Mg, Ca, and pH (p < 0.05). This research not only expands our understanding of cave ecosystems but also sets a new precedent for exploring the ecological impact of fungi in extreme environments.

The effect of botanical pesticide application and mycorrhiza on colonization of mycorrhiza, soil microbial communities, growth and yield of maize on Ultisols

An experiment to study the effect of synthetic and botanical pesticide and arbuscular mycorrhizae (AMF) on mycorrhizal colonization, population of soil microbes, growth and yield of maize on Ultisols was carried out in green house of Agriculture Faculty, Universitas Padjadjaran at Jatinangor, Sumedang District, West Java Indonesia The experiment design used was Factorial Randomized Block, consisted two factors. The first factor was pesticide consisted five levels i.e. without pesticide; neem (Azadirachta indica A. Juss) pesticide; Annona muricata pesticide ; furadan and regent. The second factor was mycorrhiza consisted two levels i.e. without AMF inoculation and AMF inoculation. The experiment consisted two units with three replications; the first unit was harvested in the end of vegetative period to observe percentage of mycorrhizal infection, population of soil bacteria and fungi, fosfor uptake and dry weight of shoot, and the second unit was harvested in the end of generative period to find out the yield of maize. The results of this experiment showed that there was no interaction effect between pesticide and AMF on percentage of mycorrhizal infection, population of soil bacteria and fungi, fosfor uptake, dry weight of shoot and yield of maize. Pesticide decreased percentage of mycorrhizal infection and population of soil bacteria and increased yield of maize. Furthermore, AMF increased fosfor uptake and yield of maize.

Case study: Mangrove phyllosphere fungal populations in agro-waste management

Case study: Mangrove phyllosphere fungal populations in agro-waste management

Fungal Diseases in Yerba Mate: Status and Management Strategies.

Yerba mate (Ilex paraguariensis St. Hil.), with its health benefits and socioeconomic significance, plays a crucial role in Argentina and other South American countries like Brazil and Paraguay. Its cultivation in the Province of Misiones (Argentina) supports various sectors, contributes to regional development, and provides employment opportunities. However, the transition from extractive practices to monoculture, accompanied with increased demand, has led to phytosanitary challenges. Imbalanced native microbiota, disease development, and pathogen dispersion have become prevalent issues. Understanding the known pathogens associated with yerba mate plants is crucial for developing effective agricultural strategies. The primary objective of this study is to synthesise current knowledge on prevalent fungal diseases in yerba mate cultivation, as well as to provide agricultural management recommendations for effective disease control. Fungal diseases can cause significant damage to different parts of the plant, resulting in economic losses. The proximity of neighbouring plantations to yerba mate crops may contribute to the cross-contamination of pathogens, emphasizing the need for comprehensive epidemiology and accurate diagnosis. Multiple fungal genera have been reported to cause pathologies in yerba mate. Among the fungi causing foliar diseases are Ceratobasidium niltonsouzanum, Cylindrocladium spathulatum, Pseudocercospora mate, Asterina sphaerelloides, Colletotrichum gloeosporioides aff var. yerbae, and Phyllosticta sp. Caulinary diseases are caused by Alternaria sp., Phoma sp., Colletotrichum sp., and Ceratocystis fimbriata. Regarding root rot, the genera Rhizoctonia sp., Pythium sp., Fusarium sp., and Rosellinia sp. have been reported. Proper crop management practices and monitoring are essential for effective disease control. To reduce reliance on chemical compounds, the use of biocontrol agents like Trichoderma sp. has shown promise in regulating phytopathogenic fungi populations. Continued research is vital to preserve the yerba mate industry and ensure its long-term viability while minimizing environmental impact.

Insights on soil biological properties and crop yields under natural farming in western Himalaya

Sustainability of agricultural production systems is a major concern in context to present environmental conditions. Natural farming (NF) is being promoted as low-cost environment friendly option. A study was carried out to investigate the effects of NF vis-a-vis organic farming (OF) and conventional farming (CF) systems on soil microbial population, enzymatic activity, and microarthropod population under tomato crop in the mid-hill zone of Himachal Pradesh, India. The results showed that bacterial population under NF increased by 42.8% and 24% in comparison to CF and OF, respectively. Similarly, the population of soil fungi and actinomycetes under NF increased by 80.5 and 67.7% over CF, and by 47.9 and 39.6% over OF, respectively. The soil dehydrogenase activity under NF (22.5µg TPF/g soil/h) was 150.6% higher than CF and 85.2% higher than OF. Similar trend was found for phosphatase and urease activity. Soil micro arthropod population after two years of experiment was also highest under NF followed by OF and CF. The system yield was statistically at par to each other, among different farming systems. All the soil biological parameters were significantly correlated with each other (P&lt;0.001, N=42). However, the correlation of these parameters was not significant for crop yield.

Characterization of ectomycorrhizal fungal community of Abies Pindrow using sporocarp sampling, morphotyping, and metabarcoding through next-generation sequencing.

Abies pindrow, commonly known as the West-Himalayan Fir, holds great ecological importance as a native tree species in the Himalayas. Beyond its value as a fuel and timber source, it serves as a keystone species within the ecosystem. However, over recent years, extensive degradation and deforestation have afflicted A. pindrow forests. Utilizing ectomycorrhizal fungal symbionts of A. pindrow could prove pivotal in restoring these deteriorated forests. This study aimed to evaluate the diversity and composition of the ectomycorrhizal fungal community associated with A. pindrow. We employed ectomycorrhizal root tip morphotyping, sporocarp sampling, and Illumina MiSeq metabarcoding of the ITS region of fungal nrDNA. The ectomycorrhizal root tips were categorized into 10 morphotypes based on their morphological characteristics, exhibiting an average colonization rate of 74%. Sporocarp sampling revealed 22 species across 10 genera, with Russula being the most prevalent. The metabarcoding yielded 285,148 raw sequences, identifying 326 operational taxonomic units (OTUs) belonging to 193 genera, 114 families, 45 orders, 22 classes, and 6 divisions. Of these, 36 OTUs across 20 genera were ectomycorrhizal, constituting 63.1% of the fungal community. Notably, Tuber was the most abundant, representing 37.42% of the fungal population, followed by Russula at 21.06%. This study provides a comprehensive understanding of mycorrhizal symbionts of A. pindrow. The findings hold significant implications for utilizing dominant ectomycorrhizal fungi in reforestation endeavors aimed at restoring this important Himalayan conifer.

Viruses shuttle between fungi and plants

The intimate relationships between plants and fungi provide an opportunity for the shuttling of viruses. Dai et al. recently discovered that a virus undergoes cross-kingdom transmission, and naturally spreads to both plant and fungal populations. This finding expands our understanding of viral host range, evolution, transmission, and disease management.

Microbial population and yield of rice–wheat system under variable irrigation and nutrient management

A field experiment was conducted during rainy (kharif) season of 2018–19 and winter (rabi) season of 2019–20 at the Water Management Research Farm of CSK Himachal Pradesh Agricultural University, Palampur, Kangra, Himachal Pradesh to study the effect of moisture and nutrient management practices on different soil microbial entities and crop yields in rice (Oryza sativa L.)–wheat (Triticum aestivum L.) system. Experiment was laid out in a split-plot design with 3 replications. Treatments comprised of 3 irrigation levels, viz. Recommended critical stages regimes; Irrigation at 0.8 CPE (cumulative pan evaporation) (rice) and 0.6 CPE (wheat); Irrigation at 1.0 CPE (rice) and 1.0 CPE (wheat) assigned to main-plots and 4 nutrient management practices, viz. Inorganic; Organic; Natural farming; and Integrated management allotted to sub-plots. Irrigation at critical stages resulted in significantly higher rice yield, bacterial, azotobacter, phosphate solubilizing bacteria (PSB), actinomycetes population. However, fungi population increased under higher moisture regimes. In case of wheat crop, irrigation at 1.0 CPE resulted in a significantly higher yield (7.5% higher over irrigation at critical stages) in both the years of study. Organic and integrated nutrient management practices being statistically at par with each other recorded significantly higher microbial population. A significantly higher fungi population was, however, recorded with natural farming. The highest crop yields were obtained with integrated nutrient management (3.4 t/ha rice and 3.6 t/ha wheat in second year). The best combination for rice was irrigation at critical stages along with integrated nutrient management. Whereas, for wheat irrigation at 1.0 CPE with same nutrient management proved to be the best. Hence it is recommended to follow integrated nutrient management and irrigation at critical stages in rice and at 1.0 CPE in wheat for higher productivity as well as for improved biological properties of soil.

Unveiling the Ecological Ramifications of Aerial Pesticide Application by Drones on Soil Microbiota in Rice

The ecological consequences of aerial pesticide application by drones on soil microbiota in rice fields were investigated in this study. The quantitative and qualitative effects of different pesticide treatments, both applied via drones and power sprayer, were examined on soil bacteria, actinomycetes, and fungi. The average population of total bacteria and pseudomonas in the rhizosphere soil tended to be slightly higher in the drone-sprayed treatments compared to the power sprayer treatments. It is evident that the drone spraying treatments resulted in higher average populations of actinomycetes and fungi (124.75 CFU × 105 g-1 soil and 21.12 CFU × 104 g-1 soil, respectively) compared to the power sprayer treatments with average populations of 127.75 CFU × 105 g-1 soil for actinomycetes and 22.5 CFU ×104 g-1 soil for fungi. Qualitative assessment of microbial groups revealed that, the abundance of G -ve bacterial groups are higher when compared to G +ve bacterial groups in rhizospheric soil before harvest of the crop. The distribution of fungal genera varied due to pesticide applications. The mean per cent occurrence of Curvularia spp., Penicillium spp., and Trichoderma spp. was slightly higher in the drone-sprayed treatments (9.85%, 8.51%, and 8.33%) compared to the power-sprayed treatments (2.48%, 2.24%, and 2.00%). However, the mean per cent occurrence of Aspergillus species (A. ochraceous, A. niger, and A. flavus) was relatively higher in the power sprayer treatments (9.14%, 12.81%, and 4.09%) when compared to the drone-sprayed treatments (3.75%, 2.31%, and 0.83%). Overall, this study underscores the need for further research to comprehensively understand the implications of different pesticide application methods on soil microbial communities and their potential impact on soil fertility and ecosystem functioning over time.

Erythromycin mediates co-flocculation between cyanobacterium Synechocystis sp. PCC 6803 and filamentous fungi in liquid cultivation without organic compounds

Photoautotrophic cyanobacteria assimilate the greenhouse gas carbon dioxide as their sole carbon source for producing useful bioproducts. However, harvesting the cells from their liquid media is a major bottleneck in the process. Thus, an easy-to-harvest method, such as auto-flocculation, is desirable. Here, we found that cyanobacterium Synechocystis sp. PCC 6803 co-flocculated with a natural fungal contamination in the presence of the antibiotic erythromycin (EM) but not without EM. The fungi in the co-flocculated biomass were isolated and found to consist of five species with the filamentous Purpureocillium lilacinum and Aspergillus protuberus making up 71% of the overall fungal population. The optimal co-cultivation for flocculation was an initial 5 mg (fresh weight) of fungi, an initial cell density of Synechocystis of 0.2 OD730, 10 µM EM, and 14 days of cultivation in 100 mL of BG11 medium with no organic compound. This yielded 248 ± 28 mg/L of the Synechocystis-fungi flocculated biomass from 560 ± 35 mg/L of total biomass, a 44 ± 2% biomass flocculation efficiency. Furthermore, the EM treated Synechocystis cells in the Synechocystis-fungi flocculate had a normal cell color and morphology, while those in the axenic suspension exhibited strong chlorosis. Thus, the occurrence of the Synechocystis-fungi flocculation was mediated by EM, and the co-flocculation with the fungi protected Synechocystis against the development of chlorosis. Transcriptomic analysis suggested that the EM-mediated co-flocculation was a result of down-regulation of the minor pilin genes and up-regulation of several genes including the chaperone gene for pilin regulation, the S-layer protein genes, the exopolysaccharide-polymerization gene, and the genes for signaling proteins involved in cell attachment and abiotic-stress responses. The CuSO4 stress can also mediate Synechocystis-fungi flocculation but at a lower flocculation efficiency than that caused by EM. The EM treatment may be applied in the co-culture between other cyanobacteria and fungi to mediate cell bio-flocculation.

Succession of tissue microbial community during oat developmental

Investigating oat tissue microflora during its different developmental stages is necessary for understanding its growth and anti-disease mechanism. In this study, 16S rDNA and ITS (Internally Transcribed Spacer) high-throughput sequencing technology were used to explore the microflora diversity of oat tissue. Twenty-seven samples of leaves, stems, and roots from three developmental stages, namely the seedling stage (SS), jointing stage (JS), and maturity stage (MS), underwent sequencing analysis. The analysis showed that 6480 operational taxonomic units (OTUs) were identified in the examined samples, of which 1698 were fungal and 4782 were bacterial. Furthermore, 126 OTUs were shared by fungi, mainly Ascomycota, Basidiomycota, and Mucoromycota at the phylum level, and 39 OTUs were shared by bacteria, mainly Actinobacteriota and Proteobacteria at the phylum level. The microbial diversity of oat tissue in the three developmental stages showed differences, and the α-diversity of the bacteria and β-diversity of the bacteria and fungi in the roots were higher than those of the stems and leaves. Among the bacteria species, Thiiopseudomonas, Rikenellaceae RC9 gut group, and Brevibacterium were predominant in the leaves, MND1 was predominant in the roots, and Lactobacillus was predominant in the stems. Moreover, Brevibacterium maintained a stable state at all growth stages. In the fungal species, Phomatospora was dominant in the leaves, Kondoa was dominant in the roots, and Pyrenophora was dominant in the stems. All species with a high abundance were related to the growth process of oats and antagonistic bacteria. Furthermore, connection modules were denser in bacterial than in fungal populations. The samples were treated with superoxide dismutase and peroxidase. There were 42 strains associated with SOD (Superoxide dismutase), 60 strains associated with POD (Peroxidase), and 38 strains in total, which much higher than fungi. The network analysis showed that bacteria might have more dense connection modules than fungi, The number of bacterial connections to enzymes were much higher than that of fungi. Furthermore, these results provide a basis for further mechanistic research.

Association between sleep pattern, salivary cariogenic bacteria and fungi populations, pH and buffering capacity in children: A comparative study.

Sleep quality has a significant impact on a child's health and is linked to oral and systemic diseases. It affects the circadian rhythm, which plays a crucial role in regulating the balance of the endocrine and hormonal systems. Current research has focused on exploring its role in the development of caries, which is influenced by inherent oral factors such as the composition of the oral microbiome and pH levels. This study aimed to investigate the relationship between bacterial population, pH, and buffering properties of saliva and sleep patterns in 8- to 12-year-old children. This cross-sectional study was conducted on 85 elementary school children aged 8-12 years. After obtaining written consent, non-stimulating saliva samples were collected using the spitting method. The participants' sleep pattern information was obtained with the use of the Persian version of the Children's Sleep Habits Questionnaire (CSHQ). Based on the results of the CSHQ, the participants were divided into 2 groups: those with appropriate sleep patterns; and those with inappropriate sleep patterns. The study compared the bacterial population of Streptococcus mutans, Lactobacillus spp. and Candida albicans, as well as the buffering capacity and pH of the saliva between the 2 groups. The statistical analysis employed the χ2 test, the independent samples t-test and Spearman's correlation. The group with inappropriate sleep patterns had significantly lower pH and buffering capacity (p < 0.001) and significantly higher colony counts of Lactobacillus and S. mutans (p < 0.001 and p = 0.012, respectively). There was no association between C. albicans and sleep patterns (p = 0.121). Inappropriate sleep patterns increase the population of caries-causing bacteria and reduce salivary pH and buffering capacity. This can be a significant factor in the development of dental caries in children aged 8-12 years.

The characteristics of fungal responses to uranium mining activities and analysis of their tolerance to uranium

The influence of uranium (U) mining on the fungal diversity (FD) and communities (FC) structure was investigated in this work. Our results revealed that soil FC richness and FD indicators obviously decreased due to U, such as Chao1, observed OTUs and Shannon index (P<0.05). Moreover, the abundances of Mortierella, Gibberella, and Tetracladium were notably reduced in soil samples owing to U mining activities (P<0.05). In contrast, the abundances of Cadophora, Pseudogymnoascus, Mucor, and Sporormiella increased in all soil samples after U mining (P<0.05). Furthermore, U mining not only dramatically influenced the Plant_Pathogen guild and Saprotroph and Pathotroph modes (P<0.05), but also induced the differentiation of soil FC and the enrichment of the Animal_Pathogen-Soil_Saprotroph and Endophyte guilds and Symbiotroph and Pathotroph Saprotroph trophic modes. In addition, various fungal populations and guilds were enriched to deal with the external stresses caused by U mining in different U mining areas and soil depths (P<0.05). Finally, nine U-tolerant fungi were isolated and identified with a minimum inhibitory concentration range of 400–600 mg/L, and their adsorption efficiency for U ranged from 11.6% to 37.9%. This study provides insights into the impact of U mining on soil fungal stability and the response of fungi to U mining activities, as well as aids in the screening of fungal strains that can be used to promote remediation of U mining sites on plateaus.

Effects of Different Conditioners on Soil Microbial Community and Labile Organic Carbon Fractions under the Combined Application of Swine Manure and Straw in Black Soil

The return of straw and manure to agricultural fields can impact soil organic carbon (SOC) and biological properties. However, there is a lack of research on how to use swine manure, maize straw, and various conditioners together affects soil bacterial and fungal populations. This study aimed to investigate six treatments, namely, only maize straw (S00), maize straw combined with swine manure (S0Z), maize straw combined with biochar and swine manure (SCZ), maize straw combined with boron slag and swine manure (SBZ), maize straw combined with biological agent and swine manure (SJZ), and maize straw combined with bio-organic fertilizer and swine manure (SFZ). The results showed that after the two-year return, all treatments increased the SOC content in 2023, which was 12.55–26.89% higher than S00. And the SCZ treatment significantly increased the soil organic carbon (SOC), dissolved organic carbon (DOC), easily oxidizable carbon (EOC), particulate organic carbon (POC), and microbial biomass carbon (MBC) content by 26.89%, 25.44%, 56.88%, 16.08%, and 43.54%, compared to S00. A redundancy analysis (RDA) showed that the continuous application of manure, maize straw, and conditioners has a positive impact on the diversity and abundance of soil microbial communities, enhancing the accumulation of soil carbon. Furthermore, our research revealed that soil fungi exhibited higher sensitivity in soil carbon composition following the addition of manure, straw, and conditioners to agricultural fields than bacteria. In conclusion, the addition of different conditioners to the fields is beneficial to biodiversity conservation from the perspective of achieving soil carbon storage and soil protection. Our findings suggested that the combination of maize straw, biochar, and swine manure was been proven to be the most effective treatment for increasing labile organic carbon fractions and enhancing the microbial community.

Importance of Soil Health for Coffea spp. Cultivation from a Cooperative Society in Puebla, Mexico

The cultivation systems of Coffea spp. in a cooperative society in Puebla, Mexico, include Rustic, Traditional Polyculture, Commercial Polyculture, Unshaded Monoculture and Shaded Monoculture. In this work, the properties of the soil were analyzed through physical, chemical and biological analyses to determine its nutritional status. Composite sample analyses were conducted to determine physical, chemical and microbiological parameters (fungi, actinomycetes, mesophilic bacteria, nitrifying and denitrifying bacteria). Leaf nutrients were determined. Rustic was the cropping system with the highest amount of K in the soil and nutrient assimilation in the leaf (N, P, K and Fe) (p = 0.001); in addition, it had high populations of mesophilic bacteria, fungi and actinomycetes and very low nitrification and denitrification rates. The principal component analyses (PCA) (&gt;3.25%) indicated that actinomycetes and K in soil favor the assimilation of Fe, K and P. This Coffea spp. cultivation system generated a lower impact on soil health than the rest of the systems and favored forest ecosystem conservation.

Assessment of Quality, Fungal Population and Diversity, of Irrigation Water in Selected Areas of Minna, Niger State, Nigeria

Water samples were collected at 3 slope positions (upper, middle and lower) from four locations practising irrigation agriculture in Minna as follows; Fadikwe, Mechanic village in keterin-gwari, Soje-A in kpakungu and Bali in Chanchaga and fitted to a Completely Randomized Design (CRD) having slope positions as replicates for each treatment. Water sampling, Physical and chemical properties and Fungi population and diversity were determined using standard methods. Data generated were subjected to Analysis of Variance (ANOVA) and means were separated using Least Significance Differences (LSD) and Duncan Multiple Range Test. Result obtained revealed that Chanchaga irrigation water recorded the highest fungi population of 1.6 x 107 CFU/ml why fungi diversity was the least at Chanchaga. The presence of _Geotrichum species_ (2.33 x 106CFU/ml), _Candida tropicalis_ (4.33 x 106CFU/ml) and _Torulopsis glabrata_ (1.67 x 106CFU/ml) in water obtained from Mechanic village may be due to the presence of hydrocarbons in the oil polluting the water. They are potential degraders of crude oil hydrocarbons. They may therefore be responsible for the value of Biochemical Oxygen Demand of 261 mg/l recorded at Mechanic village. The Biochemical Oxygen Demand values of 342 mg/l and 360.00mg/l recorded at Fadikwe and Soje A respectively may be due to the presence of _Aspergillus niger.Aspergillus niger_ is a utility biological indicator of level of degradation of pollutant. These values were however higher than the Food and Agriculture organisation (FAO) standards for irrigation water. Further studies should however be carried out to investigate the bioremediating potentials of the fungi species identified in irrigation water obtained from Chanchaga.

Plant and soil responses to tillage practices change arbuscular mycorrhizal fungi populations during crop growth.

Tillage practices can substantially affect soil properties depending on crop stage. The interaction between tillage and crop growth on arbuscular mycorrhizal fungi (AMF) communities remains unclear. We investigated the interactions between four tillage treatments (CT: conventional tillage, RT: reduced tillage, NT: no tillage with mulch, and SS: subsoiling with mulch), maintained for 25 years, and two wheat growth stages (elongation stage and grain filling stage) on AMF diversity and community composition. The AMF community composition strongly changed during wheat growth, mainly because of changes in the relative abundance of dominant genera Claroideoglomus, Funneliformi, Rhizophagu, Entrophospora, and Glomus. Co-occurrence network analysis revealed that the grain filling stage had a more complex network than the elongation stage. Redundancy analysis results showed that keystone genera respond mainly to changes in soil organic carbon during elongation stage, whereas the total nitrogen content affected the keystone genera during grain filling. Compared with CT, the treatments with mulch, i.e., NT and SS, significantly changed the AMF community composition. The change of AMF communities under different tillage practices depended on wheat biomass and soil nutrients. NT significantly increased the relative abundances of Glomus and Septoglomus, while RT significantly increased the relative abundance of Claroideoglomus. Our findings indicate that the relative abundance of dominant genera changed during wheat growth stages. Proper tillage practices (e.g., NT and SS) benefit the long-term sustainable development of the Loess Plateau cropping systems.