ISSN Electrónico 2395 - 8030.
Global Research Trends on Plant Growth-Promoting Rhizobacteria in Maize (Zea mays L.): A Bibliometric Analysis
Maize cultivation faces growing challenges due to adverse environmental conditions and reliance on chemical fertilizers, which compromise its sustainability. In response, plant growth-promoting rhizobacteria (PGPR) have emerged as a viable biotechnological alternative for enhancing crop yields, reducing fertilizer use, and mitigating environmental impact. This study, conducted in 2024, aimed to analyze scientific trends, emerging topics, and significant contributions regarding the use of PGPR in maize through a bibliometric analysis. A total of 882 publications (1986–2024) were collected and analyzed using VOSviewer sof tware, examining patterns of co-authorship, co-citation, and keyword co-occurrence. The contributions of countries such as Brazil, China, and Pakistan were highlighted, as well as the relevance of bacterial genera such as Azospirillum, Pseudomonas, and Bacillus for their positive ef fects on maize yield, abiotic stress tolerance, and fertilizer use ef ficiency. The results reveal a thematic evolution from rhizobacteria characterization toward applications focused on agricultural resilience. It is concluded that PGPR have strong potential to enhance agricultural sustainability, especially when integrated with local germplasm and traditional practices of Indigenous communities such as the Mixe, Nahuatl, and Totonac peoples. The discovery of nitrogen-fixing bacteria in the mucilage of native maize varieties represents a key opportunity; however, ef fective implementation requires overcoming technical, regulatory, and sociocultural barriers through multidisciplinary research and technological transfer to the field.
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Impact of a Sargassum spp. Ferment on Agronomic Attributes on Jalapeño Pepper Seedlings Subjected to Salinity
Agriculture faces challenges due to climate change, such as water scarcity, soil degradation, and salinity, the latter exacerbated by the excessive use of fertilizers. Salinity induces abiotic stress in plants, altering their metabolism and af fecting their development. In the search for alternatives to mitigate plant stress, biostimulants have emerged as a tool to improve crop yield and quality under both optimal and stressful conditions. Currently, the brown macroalga Sargassum spp. (sargazo) has experienced massive influxes in tropical and subtropical regions, the accumulation of which impacts marine ecosystems, coastal communities, and local economic activities. However, Sargassum represents a potential alternative in agriculture as a biostimulant due to its content of bioactive compounds. The objective of this study was to evaluate the ef fect of foliar and drench applications of a liquid ferment derived from Sargassum spp. on the agronomic attributes of jalapeño pepper seedlings subjected to saline stress, with 100 mM NaCl incorporated into the nutrient solution. Drench treatments, particularly at a concentration of 2.5% (FD-2.5%), significantly improved these attributes. The FD-2.5% treatment increased stem height (15%) and diameter (13%), as well as fresh shoot biomass and dry root biomass by 12% and 26%, respectively, compared with the saline control. Therefore, drench application of the liquid ferment derived from Sargassum spp. may represent an alternative to promote the growth of jalapeño pepper seedlings under saline stress.
Ef fectiveness of Starch Obtained from Potato and Banana Waste for the Treatment of Leachate
The production of landfill leachate has become a source of water pollution. The coagulation–flocculation method has been used to remove contaminants from leachate using chemical coagulants. In the search for natural coagulants, starch obtained from potato and plantain waste has been considered as an alternative for this process. The objective of this study was to evaluate the ef fectiveness of contaminant removal from landfill leachate using potato and plantain starch obtained from agro-industrial waste. Potato and plantain starch were extracted using both wet and dry methods. The optimal starch dosage and pH for maximum turbidity removal were determined. Subsequently, four treatments were evaluated: T-A (aluminum sulfate), T-AB (sulfate + plantain starch), T-AC (sulfate + potato starch), and T-BC (potato + plantain starch), using the coagulation–flocculation method. This analysis was performed according to ASTM International standard procedures using jar test equipment. Turbidity and chemical oxygen demand (COD) were determined, and their removal percentages were calculated. Analysis of variance and Tukey’s test were performed using STATISTICA 7 sof tware. The results showed that pre-acidification of the leachate to pH 2.5 yielded better turbidity removal (70.1–83.7%) and COD removal (37.8–39.6%) across all treatments, with no significant dif ferences among them. It is concluded that natural coagulants obtained from potato and plantain waste are more ef fective under acidic pH conditions and represent an alternative to reduce the use of chemical coagulants and minimize their environmental impact.
Water Quality Challenges in Central Veracruz, Mexico: A Comprehensive Review
Major rivers in Veracruz show significant levels of contamination, closely linked to agro-industrial activities—particularly sugarcane cultivation—and the intensive use of fertilizers and pesticides, with implications for human health, the environment, and productive activities. In the central region of the state of Veracruz, Mexico, water quality faces increasing pressure due to the discharge of domestic and industrial wastewater, leachates from sanitary landfills, climate change, and accelerated population growth. These factors af fect water availability and compromise its safety for human consumption and environmental balance. The purpose of this research was to identify the main sources of contamination, analyze their impacts on the environment and public health, and recognize knowledge gaps to guide future research and public policies. The PRISMA 2020 methodology was applied to conduct a rigorous and replicable systematic review of the scientific literature. The search was carried out in Google Scholar, Springer, Taylor & Francis, and ScienceDirect. From 380 initial records, 30 articles that met the inclusion criteria (related to water quality, findings from similar regions, and studies in central Veracruz) were selected for detailed analysis. Using VosViewer, a bibliometric analysis was performed, identifying two major thematic axes: one ecological-geographical (ecosystem services, land use, wetlands, and regional characteristics) and another technical, focused on the evaluation and ef ficiency of treatment systems, particularly constructed wetlands. The findings show sustained growth in scientific production since 2015, reflecting increasing interest in sustainable solutions and integrated water management strategies. This study provides an updated overview of water-related challenges in Veracruz and highlights the urgency of strengthening public policies and appropriate technologies to improve water quality and protect this essential resource for life.
Antifungal Extracts and Metabolites from Trichoderma asperellum Samuels, Lieckf. & Nirenberg with Potential Application in the Control of Agricultural Phytopathogens
Population growth demands an increased food supply. Therefore, there is a need to develop alternatives to synthetic fungicides with low environmental impact for controlling diseases in agricultural crops. The genus Trichoderma is widely reported as a beneficial microorganism in agriculture and as a biological control strategy against phytopathogenic fungi. The fungus T. asperellum biosynthesises metabolites that are utilized by plants to stimulate growth or to tolerate pathogen attacks. In accordance with the above, this study aimed to compile information on the volatile and non-volatile metabolites reported for T. asperellum with potential use to control fungal diseases on agricultural crops. A database was compiled from articles and patents published between 2014 and 2024 in four public and two commercial databases. Records for ‘Trichoderma’ and ‘ Trichoderma asperellum’ regarding extract type, metabolite, activity, and isolation site indicated a total of 702 metabolites from T. asperellum. A total of 622 volatile metabolites were produced by twelve strains, one of which, 6-pentyl-α-pyron, has been reported to promote plant growth and exhibit significant antifungal activity. In addition, 80 non-volatile metabolites of dif ferent chemical nature were detected in nine strains of T. asperellum, with activity against phytopathogenic fungi. Among the patents, seven relate to the individual use of T. asperellum for the production of metabolites for agricultural purposes. To continue with complementary studies, such as stability, mechanism of action, and toxicity, the active ingredients in the extracts should be purified and identified. The extracts and metabolites secreted by T. asperellum could provide an eco-friendly alternative to synthetic fungicides for controlling fungal diseases in crops.
Seasonal Analysis and Multivariate Forecasting of Monthly Precipitation in Jipijapa, Manabí, Using ARIMA, ETS, NNAR, and Prophet Models (2000–2024)
The present study analyzes the variability, seasonality, and trend of monthly precipitation in Jipijapa Canton (Manabí, Ecuador), a region particularly vulnerable to climate change and water scarcity. This research is justified by the lack of detailed studies on local rainfall dynamics, despite their importance for agricultural planning and water resource management. The main objective was to evaluate the historical behavior of precipitation from 2000 to 2024 and implement comparative forecasting models. Satellite data from NASA’s POWER platform were used, and the analysis was carried out entirely in RStudio using statistical and computational modeling techniques. Four time series models were applied—SARIMA, ETS, NNAR, and Prophet—and their forecasting accuracy was assessed using MAE, RMSE, and MASE metrics, as well as rolling-origin cross-validation and the Diebold-Mariano test. The results revealed strong seasonality, with peak rainfall concentrated between January and March, and years of extreme precipitation linked to El Niño events (e.g., years 2012 and 2017). The Seasonal Mann-Kendall test indicated no statistically significant trend (p = 0.866), suggesting long-term stability in rainfall volumes. Among the evaluated models, ARIMA demonstrated superior predictive performance over NNAR (p = 0.045). It is concluded that precipitation in Jipijapa follows a highly seasonal regime, strongly influenced by ocean-atmospheric phenomena. Therefore, the use of multivariate forecasting models with climate predictors is appropriate for strengthening local climate adaptation strategies and territorial planning.
Analysis Of the Hydrological Process of Paired Forest Small Catchments and Evaluation of the Effect of Dam Construction in Channels and Gullies
Instrumented paired forest small catchments provide rainfall and runof f data to assess hydrological response and determine the ef fect of dams in streams and gullies. The hydrological response of two paired forest small catchments in the Lake Pátzcuaro watershed was evaluated: the Ichupio small catchment, where dams were constructed in streams and gullies, and the Malacate small catchment, which served as a control. The small catchments were equipped with digital rain gauges to record rainfall and long-throat weirs with ultrasonic sensors to measure discharge. Using linear and multiple regression analyses, 11 precipitation and runof f variables were evaluated to identify their influence on the hydrological response of the small catchments. Thirteen paired events exhibiting simultaneous surface runof f in both small catchments were analyzed. Analysis of the hydrological processes showed that the Malacate small catchment exhibited higher runof f magnitudes (volume, depth, coef ficient, maximum, and mean), even though both small catchments received similar rainfall amounts and intensities. The determining factors for runof f in both small catchments were total event precipitation (PTE), precipitation during the previous 2 days (PP2D), precipitation intensity over 30 minutes (IP30), and runof f duration (TESC). Each small catchment exhibited distinct responses in runof f variables due to the presence of dams in streams and gullies. Associations were identified between water and soil conservation structures and hydrological responses in the Ichupio small catchment, particularly in terms of direct runof f and peak discharge. Significant dif ferences were observed in discharge rates and hydrographs, despite similar rainfall conditions in both small catchments. The results indicate that runof f magnitude depends on the interaction among rainfall, forest cover, and the construction of dams in streams and gullies.
Ef fect of Seaweed Extract (Macrocystis pyrifera / Gelidium robustum) on the Physiological Quality of Blue Corn (Zea mays L.) Seeds Stored for Two Periods
Marine algae extracts represent a sustainable alternative and an emerging trend in agriculture. The ef fect of the marine algae extract NPKelp® on the germination and seedling quality of blue maize (Zea mays L., Tuxpeño race) was evaluated using seeds stored for 6 and 18 months. Six treatments with dif ferent extract concentrations (0, 0.4, 0.8, 1.2, 1.6, and 2.0% v/v) were evaluated in germination tests. The variables assessed were germination percentage (GP), germination speed index (GSI), plumule length (PL), primary root length (PRL), number of secondary roots (NSR), total fresh weight (TFW), and total dry weight (TDW). Data were analyzed using analysis of variance and mean comparison with Tukey’s test (p < 0.05) using SPSS sof tware. Treatment 5 showed the highest GP values (98.67% and 100%), whereas Treatment 3 showed the highest GSI values (22.34 and 10.22) in both storage periods. Likewise, Treatment 2 obtained the highest values for PL (5.83 and 6.10 cm), PRL (16.63 and 15.98 cm), TFW (11.69 and 10.44 g), and TDW (1.71 and 1.69 g). Finally, Treatments 4 and 5 showed the highest NSR values (4.41 and 3.73). Concentrations of 1.6% and 2.0% reduced some variables, suggesting a possible inhibitory ef fect. The extract improved the evaluated variables and therefore represents a viable biotechnological alternative for managing genetically valuable blue maize seeds and promoting their use in sustainable agricultural practices.
Impact of Soil Characteristics on the Nutraceutical Composition of Melon Fruits
The nutraceutical quality of Cucumis melo L. fruits is influenced by edaphic conditions, particularly in arid and semiarid regions where salinity, alkalinity, and low fertility are common. This study aimed to evaluate the relationship between soil physicochemical properties and the commercial and nutraceutical quality of melon fruits in four orchards located in Matamoros, Coahuila, Mexico. Soil analyses were conducted following the NOM-021-SEMARNAT-2000 standard, and fruit quality parameters were determined, including soluble solids, firmness, rind thickness, and the content of bioactive compounds (phenolics, flavonoids, and antioxidant capacity). Results indicated that, although fruit size and weight were homogeneous among sites, nutraceutical quality showed significant variation. The “La Roca” site exhibited the highest levels of functional compounds, while “Ardillas” stood out for its sweetness. Spearman’s correlation and principal component analyses revealed significant associations between soil organic matter, texture, and nutraceutical quality. These results highlight the impact of edaphic characteristics on the functional quality of melon fruits, providing a basis for implementing soil management strategies to enhance the nutraceutical value of melon crops in arid and semiarid conditions.
Performance Evaluation of Organic Substrate and Bioferments in Sustainable Greenhouse-Grown Bell Pepper (Capsicum annuum L.)
The search for sustainable alternatives to synthetic fertilizers has intensified interest in organic production systems, especially in high-value crops such as bell pepper (Capsicum annuum L.). The objective of this research was to evaluate the ef fectiveness of an organic substrate formulated from agro-industrial waste and three biofertilizers as a sustainable alternative to conventional chemical fertilizers in bell pepper cultivation under greenhouse conditions. The experiment was established in Los Reyes, Michoacán, Mexico, under a completely randomized design with six treatments and ten replications. The organic substrate was formulated using bovine manure (30%), coconut fiber powder (25%), rice husks (22%), sugarcane filter cake (15%), fish meal (5%), phosphate rock (2%), dolomitic lime (1%), and brewer’s yeast (1%). Three bioferments (Bio.1, Bio.2, Bio.3) with dif ferent formulations were evaluated and compared with the Steiner nutrient solution and an organic control. The measured variables included plant height, stem diameter, number of fruits, and average fruit weight. The organic substrate presented optimal physical properties, with total porosity of 88%, air porosity of 23.97%, and water retention capacity of 64.15%. Its physicochemical characteristics were also appropriate (pH 7.1, EC 0.85 dS m–¹, CEC 49.14 me 100 g–¹). Bioferment Bio.3 showed the highest ef fectiveness, producing plants with an average height of 79.1 cm and fruits weighing 203 g, values statistically similar to those obtained with conventional fertilization (85.3 cm and 200–207 g). All biofertilizers complied with microbiological standards and were free of pathogens. The findings demonstrate that the organic substrate combined with Bio.3 constitutes a technically viable and environmentally sustainable alternative for greenhouse bell pepper production, providing yields and fruit quality comparable to conventional systems while promoting circular economy principles and reducing dependence on synthetic inputs.
InfiltR: a Tool to Model Soil Water Infiltration
Water infiltration into the soil is a fundamental process in the hydrological cycle, directly influencing plant water availability, aquifer recharge, and human access to water. This study aimed to develop an interactive application using Shiny to automate the simulation, computation, and prediction of infiltration dynamics based on the cylinder method. The application was developed in R, integrating multiple essential libraries to ensure robust functionality. The theoretical framework and computational procedures were based on peer-reviewed scientific literature documenting standardized infiltration estimation methodologies. The resulting application, infiltR, not only simulates and quantifies infiltration but also allows users to customize parameters, thereby optimizing and improving the understanding of soil infiltration processes. Moreover, the application enables real-time infiltration forecasting based on two mathematical models. This open-source tool is freely accessible, with its complete source code available on GitHub for modification and improvement. Furthermore, a comprehensive instructional video on its use will be published on YouTube. For advanced users, the code can also be implemented directly from R or accessed through a simple link without the need to install R. This application has significant potential for both real-time field applications and educational settings, providing deeper insight into the mechanisms governing soil water infiltration.
Why Does Clay Soil Have Low Cation Exchange Capacity? Mineral and Elemental Composition of Silts and Clays
Acidic soils in the Mexican tropics, such as those found in Tabasco, are characterized by fine texture and high organic matter content. However, they exhibit low cation exchange capacity (CEC), which limits their agricultural productivity. This study aimed to identify and characterize, for the first time, the mineralogical and elemental composition of the sand, silt, and clay fractions in an acidic alluvial-fluvial soil using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDS), and scanning and transmission electron microscopy (SEM-STEM). Results revealed that the clay fraction is predominantly composed of kaolinite, with secondary phases of gibbsite, magnetite, and iron and aluminum sesquioxides. These oxides absorb onto kaolinite surfaces, further reducing its CEC. The silt fraction was primarily composed of Al, Si, Fe, and C, with very low concentrations of Ca and Mg, indicating a limited natural nutrient reserve. Notably, small amounts of organic matter were detected in both sand and silt fractions, forming organo-mineral complexes potentially stabilized by interactions with metallic oxides, low pH, and seasonal anoxia associated with high annual rainfall (2600 mm). These findings suggest that the low CEC results not only from the mineralogical composition but also from pedoclimatic conditions that limit the soil’s chemical reactivity. Although these soils are classified as agricultural classes III and IV, their use is restricted mainly to citrus, cassava, pineapple, and forest plantations. This study provides original evidence on the structure–function relationships of fine fractions in acidic tropical soils. It highlights the importance of considering both mineralogy and geochemistry, not just texture, when designing sustainable soil management strategies in environmentally vulnerable regions.
Estimation of the Carbon Sequestration Potential of Conservation Tillage Systems in Soils of Nayarit, Mexico
Greenhouse gas emissions have unequivocally caused global warming and climate change, as documented in recent decades. The implementation of conservation tillage (CT) practices has been promoted to reduce soil degradation and as a climate change mitigation strategy through soil recarbonization. The objective of this study was to estimate the potential for soil organic carbon (SOC) sequestration under CT with 35% soil cover (2 Mg crop residues ha–¹) or 100% soil cover (4.66 or 5.64 Mg crop residues ha–¹), compared with traditional tillage (TT). In the state of Nayarit, Mexico, three study sites managed under a mixed crop–livestock system were located in soil units most suitable for agricultural production (Fluvisol, Luvisol, and Cambisol). The RothC-26.3 model was used to simulate SOC dynamics over a twenty-year period. The c factor of this model was determined through multitemporal analysis of satellite images from the Landsat platform. The results showed that, at the three sites/soils, TT would lead to an average SOC loss rate ranging from 0.119 to 0.341 Mg ha–¹ year–¹, whereas under CT, the model predicted average SOC accumulation rates ranging from 0.084 to 0.650 Mg ha–¹ year–¹, except in the Fluvisol under CT with 35% cover, where simulations indicated an average SOC loss of 0.129 Mg ha–¹ year–¹. The study concluded that SOC sequestration depended mainly on clay content and the amount of residues used as soil cover, particularly in Fluvisols, where residue cover must exceed 35% (> 2 Mg crop residues ha–¹ year–¹) to achieve positive SOC sequestration rates.
Control of Convolvulus arvensis with Alternative Herbicides to Glyphosate in Pre-Planting under Conventional Tillage in Bean-Sorghum Rotation: North of Tamaulipas
Field bindweed (Convolvulus arvensis L.) is a perennial broadleaf weed of agronomic importance in northern Tamaulipas, particularly during the early growing season of sorghum and maize. The present study aimed to evaluate the ef ficacy of synthetic herbicides as alternatives to glyphosate for controlling field bindweed prior to sorghum sowing under conventional tillage and rainfed conditions in a bean–sorghum rotation. Trials were established in Río Bravo, Tamaulipas, in plots of 20 × 300 m (6000 m²) per treatment, with applications on December 17, 2021 (O–I, 2021–2022), and March 3, 2023 (O–I, 2022–2023). The herbicides evaluated (g a.i. ha–¹) were glyphosate; glyphosate + 2,4-D; glufosinate ammonium; glufosinate ammonium + 2,4-D; paraquat; paraquat + 2,4-D; saflufenacil; picloram + 2,4-D; dicamba + 2,4-D; and an untreated control. At the end of the evaluation period, field bindweed was the dominant species, while other weeds included Amaranthus palmeri, Helianthus annuus, Parthenium hysterophorus, and the perennial Solanum elaeagnifolium. Precipitation was the climatic factor showing the greatest variation between cycles, af fecting herbicide ef ficacy. In 2021–2022, glyphosate control was moderate (76–86%), similar to that of other treatments, whereas in 2022–2023 it was poor to moderate (50–75%), surpassing only paraquat. Considering a minimum ef ficacy threshold of 87.5% and treatment cost, the hormonal herbicides picloram + 2,4-D and dicamba + 2,4-D were identified as the most ef fective alternatives to glyphosate for managing field bindweed in extensive cropping systems in northern Tamaulipas.
Effect of Microbial Biostimulants on Fruit Yield and Fruit Quality of Cherry Tomato (Solanum lycopersicum L. var. cerasiforme)
Cherry tomato (Solanum lycopersicum var. cerasiforme) is a crop of great economic importance due to its high demand for fresh consumption and the benefits of its bioactive compounds for human health. However, the excessive use of agrochemicals in its cultivation has generated negative effects on the environment and on human and animal health. Therefore, alternatives are being sought to reduce these effects, such as plant biostimulant microorganisms. The objective of this study was to evaluate the effect of Trichoderma harzianum, Bacillus subtilis, and Azospirillum brasilense as biostimulants on quality and yield parameters of greenhouse-grown cherry tomato. A completely randomized experimental design with five treatments and 44 replicates per treatment was used: T1 = 100% chemical fertilizer (CF); T2 = 50% CF + T. harzianum; T3 = 50% CF + B. subtilis; T4 = 50% CF + A. brasilense; and T5 = 50% CF + consortium (T. harzianum, B. subtilis, and A. brasilense). Morphological and physicochemical variables, as well as bioactive compounds of the fruit, were evaluated. The results were subjected to analysis of variance (ANOVA) and Tukey’s test (p < 0.05) using STATISTICA v. 12.0 for Windows. Statistical analysis showed significant differences among treatments, with plants in Treatment 4 (50% CF + A. brasilense) exhibiting the highest values for bunch weight, fruit weight, equatorial and polar diameter, total soluble solids (TSS), vitamin C, lycopene, β-carotene, color, and yield. These results suggest that inoculation with Azospirillum brasilense combined with a reduced dose of chemical fertilizer may represent an alternative strategy to increase the quality and yield of cherry tomato under greenhouse conditions.
Soil Core Bacteria and Main Edaphic Functions in Pecan Nut Trees (Carya illinoinensis) Rhizosphere in an Arid Agroecosystem
Microorganisms are fundamental for preserving plant health and productivity, thus knowledge of their composition and metabolism in a particular agroecosystem could be used as a tool to sustainably improve or maintain crop performance. Therefore, this study aimed to identify the bacterial core and its functional characteristics in the rhizosphere of Carya illinoinensis. This study was carried out in the arid north of Mexico (Viesca, Coahuila) in 2022 in an orchard of 20-25-year-old young trees, with a nut production per tree of 20-22 kg. Sampling was carried out at five points in the orchard: the four corners and the center. Metagenomic analyses of the 16S rRNA gene were performed to determine the taxonomic composition of the microbial species. In addition, functional predictions were made using Phylogenetic Community Research by Reconstruction of Unobserved States (PICRUSt) to estimate gene abundance within metabolic pathways. The ASVs of the bacterial population of the studied orchard were classified into 60 phyla, 130 classes, 392 orders, 40 families, 40 genera, and 1766 species. Proteobacteria, Acidobacteriota, and Actinobacteriota were the most abundant phyla. At the genus level, Pararheinheimera (X̅=5.5%) and two unknown genera of the Thermoanaerobaculia class (X̅=3.2% and X̅=2.7%, respectively) were the main taxa. In addition, glucose oxidation, phospholipase, and L-rhamnose production were the main metabolic pathways associated with the bacterial community, which confer plant growth-promoting properties and crop resilience under biotic and abiotic stress conditions. Thus, knowledge of the local bacteriome is a tool to propose the appropriate agronomic management to exploit the potential of key taxa to promote plant growth or isolate specific strains for the generation of biofertilizers.
Physicochemical Analysis of the Soil at Various Depths in a MIAF System in Veracruz, Mexico
The Milpa Intercropped with Fruit Trees system, implemented 22 years ago in the Los Tuxtlas region of Veracruz by scientists from INIFAP and the Colegio de Postgraduados, has determined that for every kilogram of maize produced under this system, 0.5 kg of soil is lost per year, whereas under conventional management, 35.5 kg of soil are lost per hectare per year. The objective of this study was to describe and identify the current status of soil physical and chemical properties (soil pH, electrical conductivity [EC], organic matter [OM], organic carbon [OC], texture, field capacity [FC], and carbon release [CO2]) at depths of 0–30 cm, 30–60 cm, and 60–100 cm, including a control treatment (conventional tillage + residue burning) in the MIAF-INIFAP module of Axochio, San Andrés Tuxtla, Veracruz. Twelve soil samples were collected, processed, classified into four treatments, and analysed under a completely randomized block design with three replications (T1 = 0-30 cm; T2 = 30-60 cm; T3 = 60-100 cm; T4 = control [conventional tillage + residue burning]). Statistically significant differences were found in OM, OC, and pH, whereas no significant differences were observed in EC and FC. Texture was clayey in Treatments 1, 2, and 4, and silty clay in Treatment 3. The greatest CO2 release occurred in Treatment 1, with a cumulative 28-day CO2 release of 1065.66 kg ha-1, followed by Treatments 2, 3, and 4 with 962.44, 944.11, and 926.13 kg ha-1, respectively. It is concluded that soil depth exhibits differentiated behavior; therefore, each depth should be managed differently compared with the management practices applied in annual monocultures in the region.
Biopolymers for Wastewater Treatment in the Area of Influence of the Tragadero Lagoon, Jauja Province, Junín Department, Perú – 2024
The application of biopolymers in wastewater treatment processes represents an ef fective strategy for mitigating the environmental impact of agricultural and domestic discharges. The objective of this research was to analyse the ef fectiveness of biopolymers for wastewater treatment in the area of influence of the Tragadero Lagoon, in the province of Jauja, Junín, Peru. Physicochemical parameters such as pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), faecal coliforms, and chromium were evaluated. Using the coagulation–flocculation method, doses of 1.2 mL of pectin and 1.2 g of chitosan were administered to 500 mL of wastewater, with mechanical agitation at 120 rpm for three hours, followed by one hour of sedimentation. An experimental design wasadopted to interpret the physicochemical data of the ef fluent before and af ter the application of the biopolymers. Results: The initial physicochemical analysis of wastewater from the Tragadero Lagoon showed pH 7.30, BOD 146.6 mg L–1, COD 75.0 mg L–1, TSS 51.0 mg L–1, faecal coliforms 1.3 × 10³ NMP/100 mL, and chromium 0.147 mg L–1, whereas the second physicochemical analysis showed pH 7.50, BOD 78.0 mg L–1, COD 48.5 mg L–1, TSS 42.0 mg L–1, faecal coliforms 2.4 × 10² NMP/100 mL, and chromium < 0.001 mg L–1. The use of biopolymers for wastewater treatment in the area surrounding the Tragadero Lagoon could be an ef fective solution for reducing pollution and preserving its ecosystem, since biopolymers have advantages over other wastewater treatment methods, such as their ef fectiveness in removing contaminants, their biodegradable nature, and their low cost. The information obtained in this study will be useful for environmental entities, authorities, and the local population in implementing sustainable wastewater treatment strategies.
Alternatives for Production of Agave durangensis Gentry in Nursery in Non-Conventional Substrates
Within the nursery production process, some conventional substrates present significant limitations, such as limited availability, high cost, and the environmental impact resulting from their extraction. Therefore, identifying alternative substrates can expand production possibilities by taking advantage of local inputs with lower ecological impact. The ef fect of four substrates on the germination and development of Agave durangensis Gentry plants under nursery conditions was evaluated. The trial consisted of six treatments based on mixtures of composted agave bagasse, crushed corncob, fresh pine sawdust, and enlame soil in dif ferent proportions, as well as a control treatment with a conventional mixture of peat, vermiculite, and perlite. The percentage of emergence and cumulative germination were determined, and ten months af ter planting, plant height, root ball length, root length, rosette diameter, stem diameter and root collar diameter, dry aboveground and root biomass, and the number of expanded leaves were evaluated. The results showed an emergence rate greater than 80% in most treatments, and maximum cumulative germination was reached at 42 days. A significant ef fect of substrate type on final cumulative germination was observed (p < 0.001); however, dif ferences were only detected for the substrate composed of composted agave bagasse, fresh pine sawdust, and enlame soil (S5-BAE), which showed the lowest germination (51.7%) compared with the other treatments, which reached values between 80 and 92.5%. The mixture of composted agave bagasse, fresh pine sawdust, and enlame soil (1:1:1) favored the morphological development of agave plants compared with the conventional substrate. It is concluded that non-conventional substrates allow adequate development of high-quality Agave durangensis Gentry plants at the nursery stage; therefore, they represent a viable alternative for use in both container and traditional bag production systems.
Land Use Change and Soil Comparison between 1983 and 2023 in the Municipality of Jiutepec, Morelos, Mexico
The modifications in land use and vegetation resulting from human activities are evident at both local and global scales. The primary consequences include biodiversity loss and a decline in the quality and quantity of ecosystem services. In this context, anthropogenic activities such as agriculture negatively impact ecosystems and their components, with soil being one of the most af fected resources. Therefore, a detailed study of the dynamics of these modifications constitutes a valuable tool for land management, enabling the identification of specific areas where conservation and restoration strategies can be developed. The objective of this study was to assess land use and vegetation change dynamics over a 27-year period, as well as variations in soil properties over a 40-year period in the municipality of Jiutepec, Morelos. Geographic Information Systems were used to generate vector data on land use and vegetation for the years 1995 and 2022. A simplified change matrix was constructed, and the change rate and deforestation rate were calculated. A total of 16 land use categories were identified for 1995 and 17 for 2022. The most significant changes in Jiutepec included an increase in urban areas of approximately 1136.27 ha. Regarding the deforestation rate, the most af fected categories were conserved and disturbed tropical dry forest. In the determination of soil properties, some properties currently evaluated (2023) remain within the ranges reported in the past (1983).
Assessment of Heavy Metal Contamination in Agricultural Soils with Organic and Inorganic Production Systems in Cunduacán, Tabasco, Mexico
Cocoa cultivation is the main economic source for small and large farmers in Tabasco. However, cocoa production has decreased recently due to financial, edaphic, and nutritional factors. Therefore, this study aimed to measure the concentration of heavy metals (HM) in agricultural soil. To achieve this, two polygons (P1 and P2) were selected to evaluate the environmental impact of the agricultural production system used in each polygon. The pH (hydrogen potential), OM (organic matter), apparent density (AD), real density (RD), porosity (PO), clay (C), silt (ST), sand (S), and field capacity (FC) of the examined regions were also determined. In addition, a solid waste landfill (SWLF) was included as a third sampling site (P3). This is because it is a source of contamination of the surrounding cocoa-growing areas (P1 and P2). According to Mexican standards NOM-147-SEMARNAT and NOM-021-SEMARNAT-2000, the heavy metals that exceeded the permissible limits were Cd > Ni > V for P1, Cd for P2, and Cd for P3, with significant dif ferences between polygons. The highest level of Cd was determined in P3; therefore, the concentration of Cd in P1 and P2 is associated with the use of agrochemicals and the dragging of soil particles due to the topographic position of P3.
Soil Quality and Relative land Ef ficiency in the Milpa System Intercropped with Fruit trees
The Milpa system interspersed with fruit trees (MIFT) is a multifunctional agroforestry system that seeks to increase productivity in small production units (< 5 ha). This study evaluated physical, chemical, and microbiological attributes to determine soil quality and its relationship with relative land ef ficiency (ERT) in a MIAF system. Ten sites under the MIAF system and six under monoculture were compared during two growing seasons (2018–2019). In composite soil samples, physical, chemical, and microbiological attributes were measured to calculate a soil quality index (ICS), and ERT was determined. Analysis of variance (ANOVA), Tukey’s test (α = 0.05), and principal component analysis (PCA) were performed to generate the ICS. The results showed dif ferences in bulk density, gravimetric moisture, oxidizable organic matter, total organic matter, and nutrient content, with better values in the MIAF system. The ICS was higher in the MIAF system with the maize–bean association, with bulk density, gravimetric moisture, total organic matter, and the abundance of nitrogen-fixing actinomycetes being the most important parameters identified by the PCA. The ERT showed values greater than one and did not correlate with the ICS or with any individual soil attribute. The most relevant soil quality indices showed higher values at sites under the MIAF system compared with monoculture systems. However, no correlation was observed between the ICS and the ERT.
Cocoa Production Systems: Evaluation of Fertility and MainEdaphic Limitations, South of Córdoba – Colombia
The municipalities located in the southern region of Córdoba exhibit high potential for the development of cacao cultivation (Theobroma cacao L.), whose productivity depends on specific edaphic conditions. In this context, it is essential to assess whether the soils in southern Córdoba meet the optimal conditions for the establishment and growth of the crop. This study aimed to characterise the physico-chemical properties of cacao-growing soils and to identify their main limitations. The research was conducted in 2022 across four municipalities—Tierralta, Valencia, Montelíbano, and Puerto Libertador—where 111 cacao farms of varying ages (5 to 25 years) were assessed using a quantitative approach, including field and laboratory evaluations of soil physico-chemical parameters. No signs of compaction were observed, which was consistent with low bulk density (Da) values; the predominant textural class was clay loam (F-Ar). The soil pH presented slightly acidic values that were restrictive for cacao cultivation in Montelíbano and Puerto Libertador.Phosphorus (P) content was low (<15 mg kg–¹), with high variability (CV > 100%). Organic matter showed medium to high levels, and cation exchange capacity (CEC) values were high across most of the evaluated sites. Some chemical limitations were identified, mainly in Montelíbano and Puerto Libertador. Overall, the results suggest that the study area presents suitable edaphic conditions for cacao cultivation.