--- title: "Cropland type determines arbuscular mycorrhizal fungi (AMF) density and diversity in Northwest Eth" id: "plos-one-23-cropland-type-shapes-arbuscular-mycorrhizal-fungi-amf-population-density-and" canonical_url: "https://medichelpline.com/clinical-feed/plos-one-23-cropland-type-shapes-arbuscular-mycorrhizal-fungi-amf-population-density-and" content_type: "clinical_feed_article" specialty: "General" source_name: "PLOS ONE (Medicine)" source_url: "https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0356876" published_at: "2026-08-28T14:00:00.000Z" evidence_level: "Journal Feed" license: "CC-BY-NC-4.0 / Informational Use" --- # Cropland type determines arbuscular mycorrhizal fungi (AMF) density and diversity in Northwest Eth ## Provenance & Clinical Metadata - **Canonical URL:** https://medichelpline.com/clinical-feed/plos-one-23-cropland-type-shapes-arbuscular-mycorrhizal-fungi-amf-population-density-and - **Specialty:** [General](https://medichelpline.com/clinical-feed/general.md) - **Primary Source:** PLOS ONE (Medicine) - **Source URL:** [Original Journal Publication](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0356876) - **Published At:** 2026-08-28T14:00:00.000Z - **Evidence Rating:** Journal Feed ## Executive GIST (TL;DR) - This study assessed how farm and soil fertility management affect **arbuscular mycorrhizal fungi (AMF)** population density, species diversity and richness in teff (Eragrostis tef) and maize (Zea mays) croplands in three districts of East Gojjam Zone, Northwest Ethiopia. - Field sampling covered three districts (Aneded, Awabel, Gozamin) at 2350–2500 m elevation with average annual rainfall ~1380 mm; samples were collected during the 2023 dry season (October–December). - A total of 14 croplands were sampled (7 teff, 7 maize). At each farmland five subsamples (N, S, E, W, Center) were combined to produce a composite sample; nearby uncultivated plots served as controls. - Soil handling: 1 kg composite samples were split into two 500 g subsamples for AMF spore extraction and soil parameter analysis; analyses were performed at Debre Markos University and Addis Ababa University laboratories. - AMF spores were extracted, quantified and morphologically identified. Results showed significant variation (p < 0.05) in average spore counts by district, by sampling location and by crop type. - Controls had higher average spore density (63.33 spores per 100 g dry soil) than croplands (47.59 spores per 100 g dry soil), supporting the hypothesis that cultivation and soil management reduce AMF abundance. - Maize croplands had higher AMF spore densities (up to 112.67 spores per 100 g dry soil) and a higher average AMF density (66 spores per 100 g dry soil) than teff croplands (30 spores per 100 g dry soil). - Fourteen AMF morphotypes were identified, representing three genera; **Acaulospora** and **Pacispora** were dominant. Dominant species included Acaulospora myricarpa and Pacispora franciscana. - The authors conclude that farm and soil fertility management practices decreased AMF population density and species diversity and recommend maintaining AMF diversity to support soil health and sustainable crop productivity in the context of climate change. - Study metadata: open access PLoS ONE research article; data are included in the manuscript; no specific funding declared; ethical approval and informed consent were obtained. ## Clinical Analysis & Structured Key Points Cropland type shapes arbuscular mycorrhizal fungi (AMF) population density and species diversity in Northwest Ethiopia | PLOS One Browse Subject Areas ? Click through the PLOS taxonomy to find articles in your field. For more information about PLOS Subject Areas, click here . Article Authors Metrics Comments Media Coverage Peer Review Reader Comments Figures Figures Abstract AMF play critical function in soil fertility and plant nutrition, especially in absorption and translocation of immobile nutrients. Farm and soil fertility management activities enhance crop yield; however, they either positively or negatively impact the AMF population and diversity. This study was aimed at assessing effects of farm and soil fertility management activities on AMF population density, species diversity and richness in North West Ethiopia. Soil samples were obtained from teff ( Eragrostis tef ) and maize ( Zea mays ) croplands. AMF spores were extracted, quantified, and identified. Average AMF spore population was varied significantly (p < 0.05) across districts, among specific sampling locations, and between crop types. Controls exhibited a higher average AMF population density (63.33 spores per 100 g dry soil) as compared to the average AMF population density of croplands (47.59 spores per 100 g dry soil). Maize croplands exhibited the highest average spore densities, up to 112.67 spores per 100 g dry soil and harboring a higher average AMF population density (66 spores per 100 g dry soil) as compared to the teff croplands (30 spores per 100 g dry soil). A total of 14 AMF morphotypes belonging into three genera were identified. Acaulospora and Pacispora were found dominant, while Acaulospora myricarpa and Pacispora franciscana were dominant species. Farm and soil fertility management practices decreased AMF population density and species diversity. Maintaining AMF population density and species diversity is needed to enhance soil health and crop productivity in the era of climate change to promote sustainable agriculture. Citation: Kassew D, Yimer J, Pagano MC, Assefa F, Tawfeeq Al-Ani LK, Ayele K, et al. (2026) Cropland type shapes arbuscular mycorrhizal fungi (AMF) population density and species diversity in Northwest Ethiopia. PLoS One 21(8): e0356876. https://doi.org/10.1371/journal.pone.0356876 Editor: Ying Ma, Universidade de Coimbra, PORTUGAL Received: March 25, 2026; Accepted: August 9, 2026; Published: August 28, 2026 Copyright: © 2026 Kassew et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability: All data are included in the manuscript. Funding: The author(s) received no specific funding for this work. Competing interests: The authors have declared that no competing interests exist. 1. Introduction Arbuscular mycorrhizal fungi (AMF) establish a mutual association with the roots of terrestrial plants. They play a critical role in enhancing health and productivity of agricultural ecosystems. These fungi also establish symbiotic associations with important cereal crops including economically vital crops such as teff ( Eragrostis tef ) and maize ( Zea mays ) [ 1 ]. The AMF-plant partnerships significantly enhance plant nutrient acquisition, particularly weakly mobile soil nutrients like phosphorus, nitrogen, potassium, and magnesium in agricultural ecosystems [ 2 – 5 ]. In addition to improving nutrient uptake, AMF enhance soil water retention capacity, improve plant health, and enhance resilience to numerous environmental stressors including drought, acidity and salinity stresses, and the presence of harmful soil compounds [ 1 , 2 , 6 – 8 ]. Moreover, the AMF contribution to the formation of stable soil structures, via glomalin synthesis is well established [ 1 , 6 ]. AMF often lead to healthier and more vigorous plant growth, increased biomass and yields even on nutrient-poor soils [ 9 ]. The AMF hyphae extend far beyond the plant’s root system, providing extensive surface area for nutrition absorption and translocation. AMF are more efficient in absorption and translocation of phosphorus (P), especially when it exists in less available forms in the soil. This is done by secreting enzymes and acidifying the plant rhizosphere [ 1 , 5 ]. More importantly, AMF form a common mycorrhizal network among nearby plant species which may be the same or different species and thereby share limiting nutrients among the nearby plants [ 10 ]. Several reports revealed that soil fertility management practices like tillage, intensive soil fertilization and pest management activities lead to reduced soil biodiversity including microbial diversity [ 4 , 11 , 12 ]. To mitigate and reduce the negative impacts of soil fertility and pest management practices, an alternative soil fertility management practices like organic farming practices were recommended [ 12 ]. The organic farming practices are well known for their high crop yield, favoring sustainable soil biodiversity [ 13 , 14 ]. Organic farming improves soil fertility, soil organic carbon content, and soil microbial diversity [ 15 – 17 ]. However, chemical fertilizer and pesticide application is still a common practice in agricultural ecosystems across the globe. In the last ten years, there have been intensive chemical fertilizer and pesticide application practices in the croplands in East Gojam Zone, Amhara National Regional State. However, the impacts of these soil fertility and pest management approaches on AMF population density and species diversity in teff and maize croplands has been insufficiently studied in Ethiopia in general and East Gojam zone, north west Ethiopia in particular. Therefore, there is scarcity of detailed scientific information and study concerning the effects of farm and soil fertility management practices on AMF population density and species diversity in the study areas. Here we forward these two hypotheses: (1) frequent soil disturbance disrupts AMF hyphal networks and reduces their population density as compared to non-cultivated controls; (2) maize croplands support a higher AMF population density and species diversity compared to the teff croplands. Therefore, this study was aimed at evaluating effects of the farm and soil fertility management practices on AMF population density, species diversity, community composition and species richness in teff and maize croplands in the East Gojjam Zone, Northern Ethiopia. 2. Materials and methods 2.1. Area of study This research was done in three districts: Aneded, Awabel and Gozamin in the East Gojjam Zone Amhara national regional state, North West, Ethiopia. These districts are located approximately 265 kilometers southeast of Bahir Dar, the capital of the Amhara National Regional State and 300 kilometers from the Ethiopia’s capital, Addis Ababa. The geographical coordinates of the sampling districts range between 37 0 42’00” to 37 0 45’30” east longitude and 1 00 17’00” to 1 00 21’30” north latitude. The elevation of the sampling locations range between 2350–2500 m.a.s.l. Sampling districts receive an average annual rainfall of 1380 mm, with the average lowest and highest temperature of 12 °C and 25 0 C, respectively. The agro-ecology of the sampling districts range from kola to wurch. The major crops cultivated in the sampling districts include: teff, wheat, barley, maize, engido, beans, peas, lupins, etc. 2.2. Preliminary survey and soil sampling A preliminary survey was conducted on the farm and soil fertility management practices in the sampling districts. During preliminary survey, information about previous cropping history, chemical fertilizer application, pesticide application and lime amendment history (Supplementary information 1) were carried out. The soil samples were obtained from the three districts, namely Gozamen, Aneded and Awable districts of the East Gojam Zone. These districts were selected based on their well known teff and maize production. At each district, farmlands were randomly selected. A total of 14 croplands (7 teff and 7 maize) soil samples were collected. The size of the croplands range between 0.5 hectare and 2.5 hectares. During soil sampling, a farmland was divided into five sampling points: North, South, East, West, and the Center [ 1 ]. The five sampling points were cleaned and dug up 30 cm for soil sampling. The soil samples were pooled into one composite sample. Control samples were obtained from the nearby farmlands, which were left without agricultural practices during the sampling seasons. Soils were collected in sterile polythene bags. The sample collection was carried out during dry season from October to December, 2023. The samples were carried to the Debre Markos University, Department of Biology, Mycology and Microbiology laboratory and Addis Ababa University, Department of Microbial Cellular and Molecular Biology, Applied Microbiology Laboratory for further analysis. The 1 kg soil was divided into 2 subsamples (500 g each), for AMF spore extraction and for soil parameter analysis. This study was reviewed and approved by Ethical review committee of Department of Biology, Debre Markos University. An informed consent was obtained from all the farmland owners for participating in this study. 2.3. The soil parameters Soil samples were processed and analyzed at two primary locations: the Engineering Corporation of Oromia (ECO) Soil, Water, and Plant Laboratory in Addis Ababa, and the Mycology and Microbiology Laboratory at Debre Markos University, Ethiopia. Prior to soil chemical analysis, soil sub-samples were homogenized through grinding and passed through a 2 mm mesh sieve. The following parameters were then determined: Soil pH was measured in a 1:2.5 (w/v) soil-to-water suspension, following the protocol by Carter and Gregorich [ 18 ]. Soil organic carbon (SOC) was quantified using the chromic acid titration method described by Walkley and Black [ 19 ]. Total nitrogen (TN) was determined via the Kjeldahl digestion method, as outlined by Hinds and Lowe [ 20 ](1980) and Available phosphorus (P) was extracted and measured according to the Olsen method [ 21 ]. 2.4. Arbuscular mycorrhizal fungi spore extraction Arbuscular mycorrhizal fungal (AMF) spores were isolated from the soil using a modified wet sieving and decanting technique, as detailed by Gerdemann and Nicolson [ 22 ]. A 100 g of air-dried soil samples were processed in triplicate. Each sample was submerged in 500 mL water for approximately 1–2 hours. After manually breaking down larger soil aggregates and allowing the heavy particles to settle, the resulting liquid was poured through a stacked series of sieves with mesh sizes of 500 µm, 212 µm, 106 µm, and 45 µm. The sieving process continued with tap water until the runoff was transparent. Materials caught in the 500 µm sieve were examined for the presence of spore clusters or sporo-carps; spores found were moved to the 45 µm sieve. Similarly, residues from 212 µm and 106 µm sieves were rinsed and consolidated into the 45 µm sieve. The collected materials were then moved to 15 mL Falcon tubes and subjected to centrifugation at 2000 rpm for 5 minutes. After discarding the supernatant, the pellets were re-suspended in a 50% (w/v) sucrose solution and centrifuged again for 3 minutes at 2000 rpm. The resulting supernatant was captured on a 45 µm sieve, washed thoroughly to eliminate residual sugar, and transferred to a 90 mm gridded Petri dish. Spore densities were determined using a stereomicroscope (NOVEX, ISO 1006) at 40X magnification, following the identification and counting guidelines provided by INVAM. This entire procedure was performed three times, utilizing a total of 300 g of soil. 2.5. AMF identification and characterization Individual AMF spores were isolated under a dissecting microscope using a micropipette. For permanent preservation, spores were mounted on glass slides using either Polyvinyl-Lactic acid-glycerol (PVLG) or a 1:1 (w/v) mixture of PVLG and Melzer’s reagent, following the protocols established by the Glomeromycota database ( https://maarjam.ut.ee/ ). Initial observations and digital imaging were performed using a compound microscope (Olympus-BX51) at magnifications of 20x, 40x, and 100x. Subsequently, the spores were crushed to reveal internal wall layers and allowed to air-dry at room temperature for two weeks. These crushed specimens were then re-examined and photographed under the same magnification range (20x–100x) to document detailed morphological features. Taxonomic identification to the genus and species levels was conducted based on diagnostic physical characteristics, including: spore coloration and surface ornamentation, wall structure and thickness and the morphology of the subtending hyphae. These features were cross-referenced with official descriptions from INVAM and the Glomeromycota online repository, utilizing the classification keys proposed by Schenck [ 23 ]. This identification work was carried out through collaboration between the Applied Microbiology Laboratory at Addis Ababa University (Department of Microbial, Cellular, and Molecular Biology) and the Department of Biology at the Federal University of Minas Gerais, Brazil. 2.6. AMF population density and species richness To evaluate the AMF community structure across the various sampling districts and farmland locations, the following ecological parameters were employed: 1) abundance and richness: population density (SD) was calculated as the total number of AMF spores identified 100 g -1 dry soil. Species richness (S) was defined as the total count of distinct AMF species identified within a specific sampling location or district. 2) diversity Indices: the Shannon–Wiener Index (H’) was used to assess species diversity, calculated as: H’ = Σ (ni/n)ln(ni/n), where: ni = number of individuals of species n, and n = number of all individuals of all species. The Simpson’s dominance index (D) was calculated using the formula: where ni = the total number of individuals of a single, specific species (i), N = the total number of all individuals of all species in the sample, Σ = the sum of the calculations for each individual species. 3) Occurrence and dominance: the Frequency of occurrence (FO) represents the percentage of samples in which a specific genus or species was detected, was calculated according to Fernandes et al. [ 24 ]. That is ([the number of samples in which a given species or genus was isolated/ the total number of samples] ×100). The Isolation Frequency (IF) served as a measure of species dominance. The following the classification by Chen et al. [ 25 ] was used for a species or genera to categorize based on their IF values: Accordingly, dominant: IF, IF ≥50%, common: 10% [!CAUTION] > MedicHelpline content is structured for research, educational, and professional discovery purposes. 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