En el año 1990 inicié mi Actividad como docente y becaria de Investigación. Actualmente desempeño el cargo de profesora Asociada Regular e Investigadora de la Universidad Nacional del Comahue. Soy Magister en Ciencias Agrarias, egresada de la Universidad Nacional del Sur. La temática de mi Maestría fue el Reciclado de Residuos Orgánicos. Soy Directora de un Proyecto de Investigación de la Universidad Nacional del Comahue. Estoy trabajando hacen más de 10 años en investigación y aplicación de diferentes biotecnologías como el Compostaje, Lombricompostaje y Biogás, para la degradación de residuos agropecuarios y domiciliarios RSU, generados en el Valle Inferior del Rio negro. Soy Consultora Provincial y Nacional de estudios de Impacto Ambiental.
EDUCATION
Licenciada en gestión de Empresas Agropecuarias
Magister en Ciencias Agrarias
Inscripta en Doctorado en Agronomia.
RESEARCH INTERESTS
Soy profesora Asociada Regular e Investigadora de la Universidad Nacional del Comahue. Soy Directora de un Proyecto de Investigación en la temática de degradación de residuos orgánicos a través de procesos de Compostaje, Lombricompostaje y Biogás.
The effects of compost application on soil properties: Agricultural and environmental benefits Iraji, Farida, Jiménez-Ballesta, Raimundo, Mongil-Manso, Jorge, Pellejero, Graciela, Miguélez, David, et al. International Journal of Recycling of Organic Waste in Agriculture, 2025 Purpose: Human activities generate substantial waste, often relegated to landfills or incineration. Composting offers a valuable alternative, transforming waste into organic fertilizers that can improve soil health. This review examines the multifaceted influences of compost application on soil properties, the associated agricultural and environmental benefits. Methods: A comprehensive literature review was conducted, analyzing numerous research articles focused on compost application in agricultural soils. The review prioritized studies investigating the direct and indirect effects of varying compost application rates on a range of soil properties. The search encompassed databases and scientific journals related to soil science, environmental science, and agriculture. Results: The reviewed literature consistently demonstrated that compost incorporation positively influences several key soil properties. Compost application generally led to a reduction in bulk density, indicating improved soil structure. Furthermore, it enhanced water infiltration and hydraulic conductivity, promoting better water management. Compost also increased soil water content and the availability of plant-available water, benefiting plant growth. The review highlighted that compost application generally has positive effects on agricultural and environmental soils. Conclusion: Composting offers a sustainable waste management strategy with significant potential for soil improvement. The reviewed evidence supports the widespread use of compost as a soil amendment to enhance soil physical properties, water relations, and potentially other soil chemical and biological properties. These improvements contribute to enhanced soil health, sustainable agriculture, and environmental protection, particularly in the context of degraded soil remediation. Further research is encouraged to optimize compost application rates for different soil types and cropping systems. Research Highlights · Soil Structure Improvement: Compost reduces bulk density, enhances porosity, and improves water retention, particularly in degraded soils. · Nutrient Enrichment: Provides slow-release macronutrients (N, P, K) and increases cation exchange capacity (CEC), improving long-term soil fertility. · Microbial Enhancement: Boosts microbial activity and diversity, aiding nutrient cycling and suppressing soil-borne pathogens. · Sustainable Waste Management: Diverts organic waste from landfills, reducing methane emissions and supporting circular agriculture. · Optimization Needed: Benefits depend on compost type, soil conditions, and application rates (20–30 Mg/ha every 2–3 years), requiring site-specific strategies.
Biological control of soil-borne phytopathogenic fungi through onion waste composting: implications for circular economy perspective A. Chorolque, G. Pellejero, M. C. Sosa, J. Palacios, G. Aschkar, C. García-Delgado, R. Jiménez-Ballesta International Journal of Environmental Science and Technology, 2022 The production of onion waste derived mainly from bulbs affected by fungal diseases, during onion classification and storage presents an important agro-environmental issue in onion production regions. Composting is an environmentally friendly strategy to recycle agricultural waste and produce organic fertilizers. Modifications of the microbial community in soil can affect the ability of pathogen propagules to survive, germinate and infect plant roots. Hence, the main objective of this work was to exploring the mechanisms involved on the presence of three soil-borne phytopathogenic fungi during the composting process of onion waste under the hypothesis if that the resulting compost effectively prevents or minimizes the dispersion of phytopathogenic fungi. To this end, three composting piles of 60 tonnes each were built by layering onion waste affected by phytopathogenic fungi and cow dung at 1:1 ratio. Temperature, moisture, pH, electrical conductivity (EC) and Aspergillus niger, Penicillium sp. and Fusarium sp. growth were monitored for 100 days. During the first 28 days of composting, the presence of phytopathogenic fungi increased significantly showing thereafter a downward trend. Final estimations of fungal populations densities indicated a predominance of A. niger and an effective reduction in the abundance of Fusarium sp. This pilot-scale work demonstrates the feasibility of composting onion waste contaminated with phytopathogenic fungi and highlights the positive environmental impact associated with this practice. Therefore, the composting of onion waste and cow dung is a feasible and sustainable procedure to recycle onion waste and to promote circular economy in onion production regions.
Agronomic application effects of organic wastes on a squash crop production Graciela Pellejero, Jonathan Menéndez, Julieta R. Palacios, G. Aschkar, Francisco Jesús García Navarro, et al. International Journal of Recycling of Organic Waste in Agriculture, 2022 Purpose The objective of the study was to evaluate the application effects of different doses of onion residue mixed with bovine manure compost as an organic fertilizer on a hybrid Tetsukabuto squash crop cultivated in a field.Method The experimental design required randomly dividing blocks with three replicates. The experiments were designed with different dose combinations in experimental units (4 m wide x 8 m long deep). There were three treatments: organic fertilization (two compost doses 6 and 8 kg m-2); mineral fertilization (45 kg N ha-1 urea), unfertilized control. The number of leaves, main guide length per plant and dry matter were determined.Results The results obtained during the first 15-day sampling showed significant differences (p <0.05) in both number of leaves and main guide length per plant between the treatments with compost doses and the control without fertilization. The treatment with the compost dose of 6 kgm-2 produced the highest effect. . Furthermore, there were no significant differences (p <0.05) among the three treatments in both the number of leaves and main guide length per plant during the second post-sowing 60-day sampling, as well as in the dry matter during the first sampling. During the second sampling, the percentage of dry matter in the control differed significantly from the two fertilized treatments.Conclusion Compost of onion residue mixed with bovine manure can be applied as an organic fertilizer with similar positive effects to mineral fertilization in the first squash crop implantation stage.
Effect of the application of compost as an organic fertilizer on a tomato crop (Solanum lycopersicum l.) produced in the field in the lower valley of the río negro (argentina) Graciela Pellejero, Julieta R. Palacios, Emanuel Vela, Omar Ariel Gajardo, Luis Albrecht, et al. International Journal of Recycling of Organic Waste in Agriculture, 2021 Purpose The main objective of the study was to evaluate the application of different doses of onion residue compost as mixtures with bovine manure as organic fertilizers for a round tomato crop planted in the field. Method The data were obtained experimentally in pilot fields. The experimental design was completely random-ized, with 4 m2 plots with ten plants each as an experimental unit and with three replications per treatment (2 years). Five treatments were tested, namely one unfertilized control, three with organic fertilization and one min-eral treatment. The variables measured were plant height (cm), stem base diameter (cm), fresh plant weight (g) and total dry matter (%). The parameters measured for the fruit were fresh fruit weight (g), fruit length (mm), fruit width (mm) and total soluble solids. Results The application of compost from the degradation of onion residues as mixtures with cow manure had posi-tive effects on the growth of the plant and on the development of tomato fruit. Compost doses of 60 Mg ha?1 and 80 Mg ha?1 gave similar values to chemical treatment and the control without fertilization was significantly lower than those with doses of organic and chemical fertilizer. These results indicate that this compost contains the nutrients required by the tomato crop for growth and development. Conclusion It was concluded that the agricultural use of quality compost is an effective strategy to obtain high quality products in an economically viable and environmentally sustainable way.
Onion waste recycling by vermicomposting: nutrients recovery and agronomical assessment G. Pellejero, K. Rodriguez, G. Ashchkar, E. Vela, C. García-Delgado, R. Jiménez-Ballesta International Journal of Environmental Science and Technology, 2020 Vermicomposting is an efficient technology to treat organic wastes and recover nutrients for agricultural purposes. The aim of this work was to assess the feasibility of vermicomposting to treat onion waste and the resulting vermicompost as an agricultural input. Onion waste from the food industry was mixed with cow dump and vermicomposted for 154 days at the pilot scale. The evolution of temperature, moisture, pH, electrical conductivity and total nitrogen was monitored during the vermicomposting process. Finally, the vermicompost was characterized to assess its potential use in agriculture. The vermicomposting process was carried out at moisture around 85% and maximum temperature of 33 °C. The pH decreased throughout the process, while the electrical conductivity increased. Total nitrogen concentration decreased during the first days but then was constant. The final vermicompost was a mature material (C/N = 13), with considerable carbon content (15.7%), lightly basic and with low electrical conductivity. Nutrient equilibria were 1:8:3 with appreciable content of other nutrients such as Ca, Mg and S. Toxic elements were in low concentration and below the legal threshold. The vermicomposting of onion waste with cow dump is a feasible technology to treat this waste and produce a valuable agricultural input to close the nutrient circle.
Effects of the onion residue compost as an organic fertilizer in a vegetable culture in the Lower Valley of the Rio Negro G. Pellejero, A. Miglierina, G. Aschkar, M. Turcato, R. Jiménez-Ballesta International Journal of Recycling of Organic Waste in Agriculture, 2017 PurposeFarming production in the lower part of Río Negro Valley (Argentina) has increased considerably during recent years, causing soil degradation and, specifically, decreasing the organic matter contents. This fact requires recovery measures, as organic amendments for soils, to improve its quality. The marked objectives for the present research is to evaluate compost as organic fertilizer, based on a mix of onion waste and bovine manure.MethodsThe experiment was carried out in a completely randomized design, involving five treatments and one control, with ten copies of each one. Tests were performed in a greenhouse, using flowerpots and experimental plots, in a typical soil of the region (Aridisol), pH 8.3 and 2.2% of organic matter, mixed with different compost dosages (20, 40, 60 and 80 Mg ha−1) and the chemical treatment, Urea (0.26 Mg ha−1). A horticultural farming of 1 lettuce was sowed (Lactuca sativa). A conventional handling was carried out for the whole cultivation period, and at the end was harvested. Ten plants per plot were taken and were determined total fresh weight, aerial part fresh weight, root part fresh eight. In the dry controls total dry weight, aerial dry weight and root dry weight was determined.ResultsResults show, with an error (p < 0.05), significant differences in the fresh weight per plant calculated, between treatments and control; a noticeably greater effect can be observed in the treatments with 6 and 8 kg m−2 compost amending and urea treatment. There is no evidence of the existence of significant differences (p < 0.05) between treatments and control, according to the values obtained for root size as well as aerial dry weight and root dry matter.ConclusionsIt can be concluded that the addition of organic fertilizer to soils, has positive effect on the Fresh weight of the plant, recommending the use of doses of 6 kg m−2 while the dose of 8 kg m−2 could replace the use of chemical fertilizers such as Urea.
Effects of Aspergillus niger in onion bulbs (Allium cepa L.) stored in the post-harvest phase Cristina Pozzo Ardizzi, Graciela Pellejero, Gabriela Aschkar, Raimundo Jiménez Ballesta International Journal of Postharvest Technology and Innovation, 2012 Onion bulbs were stored in the field, in piles until its commercialisation but the bulbs may be affected by fungal diseases. The objective was to assess the effects of the temperature (T), relative humidity (RH) within the piles, the water percentage (WP) and soluble solids (SS) of the bulbs over Aspergillus niger incidence. Bulbs of Cobriza INTA, Antartica INTA, Valcatorce INTA, Valuno INTA and Grano de Oro were storage in piles and T, RH, A. niger incidence, WP and SS were determined in bulbs periodically sampled. The incidence increased in the first stage of conservation, and the decreasing temperatures induced the fungal sporulation. When temperatures dropped below 14°C, the pathogen activity diminished because the detachment of affected scales. The WP and the SS were similar in coloured cultivars so they did not explain the incidence differences. The optimal conservation period ranged between two and three and a half months.
