Investigación Agraria

Valoración económica de los servicios recreativos de los Monumentos Naturales Cerro Kõi y Chorori, Areguá, Paraguay

2025-06-23T18:01:33+00:00

The Monumentos Naturales Cerro Kõi y Chorori (MNCKC) constitute a protected wilderness area in Paraguay, notable for their outcrops of columnar sandstones, which are rare geological formations found in few places around the world. Despite their ecological value, they face economic challenges in ensuring their long-term protection and conservation. The expansion of urbanization in nearby towns has driven a considerable increase in the demand for ecosystem services provided by this site. To secure the necessary resources that allow for enhancing visitor experience at the MNCKC through the implementation of a management plan, it is essential to consider their ecotourism potential. The general objective of the research was to economically value the recreational services offered by the MNCKC through the contingent valuation method. Data collection was carried out through the application of previously validated surveys in the study area, following the recommendations of Amarilla Rodríguez et al. (2023). A non-parametric analysis of the data was conducted using Kriström’s model (1990). The main reasons for visiting were nature tourism, relaxation, and the observation of geological formations—examples of cultural ecosystem services. The findings highlight the need to implement environmental access fees that consider not only visitors’ ability to pay, but also principles of equity and institutional trust.

Scientific article Sugar industry waste transformed into organic fertilizer

2025-05-27T17:55:12+00:00

Carrot is a food source rich in bioactive compounds essential for human nutrition. Being a short-cycle crop, it has high nutritional demands that are commonly satisfied through intensive use of chemical fertilizers, which increase production costs and deteriorate soil health. As a sustainable alternative, the valorization of organic waste for fertilizer production emerges. The objective of this work was to evaluate the effect of different doses of composted organic fertilizer, derived from sugar byproducts, on carrot crop growth and yield. The experiment was conducted at the experimental field of the Paraguayan Institute of Agricultural Technology (IPTA) in Caacupé, Paraguay, using the Shin Kuroda variety under a randomized complete block design with three replications per treatment. Treatments consisted of four increasing doses of organic fertilizer (2, 4, 6, and 8 t ha⁻¹) and a control treatment without fertilization. Plant height, root length and diameter, root weight, and total yield were evaluated. Data were analyzed using analysis of variance (p < 0.05). Results showed that plant height, root weight, and yield were not significantly influenced by the applied organic fertilizer doses. However, significant differences were observed in root diameter and length. It is concluded that the evaluated organic fertilizer doses were not sufficient to completely satisfy the nutritional demands of the carrot crop.

Influence of maturity stage on nutritional quality and production cost of corn silage in San Pedro de Ycuamandyyú, Paraguay

2025-05-27T17:40:41+00:00

The objective of this study was to evaluate the bromatological composition and production cost of corn silage (Zea mays L.) harvested at different maturity stages. The research was conducted in the district of San Pedro de Ycuamandyyú between January and July 2023. A completely randomized design was used with three treatments corresponding to different maturity stages of the crop at harvest and ensiling (T1 = ¼ milk line (ML), T2 = ½ ML, T3 = ¾ ML), with five replications each. Each replication consisted of a polyethylene microsilo with a capacity of 70 kg. Data were subjected to ANOVA using Fisher's test (α = 0,05), and means with significant differences were compared using Tukey's test (α = 0,05). The ¾ ML treatment showed superior values for DM (31,10%), TDN (70,55%), NFC (37,63%), and IVDMD (69,33%), and excellent CP content (7,67%). Likewise, this treatment recorded lower levels of NDF (44,92%), ADF (25,12%), LIG (1,69%), and ADIN (6,16% CP), in addition to the lowest production cost per kilogram of FM (329 Gs) and DM (1.059 Gs). Based on these results, it is recommended to harvest and ensile when the corn crop reaches the ¾ ML stage to optimize nutritional value and production cost.

Evaluation of the effectiveness and environmental impact of pre-emergent herbicides for weed control in sugarcane (Saccharum spp.)

2025-06-12T18:21:15+00:00

To evaluate the effectiveness and environmental impact of different pre-emergent herbicide treatments for weed control in sugarcane, two field experiments were conducted at different locations from April 2020 to June 2021. A floristic survey of weed species was performed to determine taxonomic composition and frequency of occurrence. Seven herbicide treatments were evaluated: Unipix GD70 (Imazapic), Merlín Total SC60 (Isoxafluotole + Indaziflan), Mayoral LS35 (Imazapic + Imazapyr), Palmero GD75 (Isoxafluotole), Palmero GD75 + Mayoral LS35, Merlín GD75 + Mayoral LS35, and Merlín GD75 (Isoxafluotole) as the standard treatment, along with an untreated control. Environmental impact coefficients and total costs per hectare were calculated for each treatment. The floristic survey revealed that weed species share close phylogenetic relationships, facilitating management through similar control practices. All herbicide treatments provided excellent weed control. Regarding environmental impact, 50% of treatments posed low risk while the remaining 50% posed very low risk. Unipix GD70 demonstrated the best cost-benefit ratio with the lowest cost per hectare per weed-free day, maintaining weed-free conditions for 90 days post-application. These results expand integrated weed management strategies as alternatives to the conventional Merlín GD75 treatment (0.200 kg ha⁻¹), providing more efficient and environmentally sustainable options for sugarcane weed control.

Foraging behavior of social wasps on jaboticaba (Plinia cauliflora) in urban area of Southeast Brazil

2025-06-17T17:32:49+00:00

Although frequently observed, the use of fruit as a food source by social wasps in fruit crops requires further study, as some of these insects can act as pests by damaging fruit. To investigate this interaction, we monitored the foraging behavior of social wasps on a jaboticaba tree (Plinia cauliflora (Mart.)) throughout a complete reproductive cycle. We recorded 13 wasp species feeding on the fruit; however, despite the potential for damage, we recommend deterring wasps only during fruit ripening. Further studies should assess whether jaboticaba fruit consumption by wasps causes significant economic damage.

Advancing toward climate-smart agriculture

2025-04-02T19:43:21+00:00

Current challenges, such as climate change and increasing pressure on primary food production, demand a transition toward more resilient and environmentally responsible agricultural models. In this context, preserving soil organic carbon (SOC) emerges as a key strategy to enhance soil functions, sustain essential ecosystem services, and strengthen agroecosystem resilience. This review article aims to analyze and synthesize the role of SOC in soil functions, its contribution to ecosystem service provision, its importance for achieving Sustainable Development Goals, and to identify the most promising management strategies for its increase and stabilization in soil. The research was based on an exhaustive bibliographic review with a descriptive approach, drawing from 43 review articles published between 2019 and 2024 in the Scopus database. The results demonstrate that SOC maintenance and enhancement are determinant factors for preserving soil functional integrity, supporting key ecosystem services, protecting food security, and mitigating climate change effects. Collectively, the findings highlight the need to promote management strategies oriented toward SOC regeneration as a central axis in building more resilient agroecosystems and advancing toward climate-smart agriculture.

Proposal for Payment for Environmental Services in the San Rafael Tekoha Guasu Reserve, Paraguay

2024-12-06T16:38:37+00:00

In 1992, the Paraguayan State declared a territory in the southeastern part of the country as a protected area, identified at the time as a site of high conservation value. The 78,000 hectares declared, today known as the San Rafael Tekoha Guasu Reserve, included extensive ancestral territories and private properties. San Rafael Tekoha Guasu is considered one of the most important conservation challenges in the country, where processes of degradation have been recorded, characterized by different illicit activities and conflicting objectives. As an alternative solution to the problem, Payment for Environmental Services (PES) mechanisms are proposed, in order to generate economic incentives for those owners who have opted for conservation, this being the general objective of the research. The qualitative research used as data collection techniques interviews with seven qualified informants, two focus groups, and analysis and mapping with the Geographic Information System (GIS). The results show more than 67 properties under public, private and community regimes. Three models of Payment for Environmental Services (PES) were designed according to Law No. 3001/06 and one for the voluntary market mechanism. This research is one of the first contributions that includes benefits of carbon markets (regulated and voluntary) in nature conservation contexts.

Incidencia del tipo de sustrato y aplicación de hormona en la multiplicación del algarrobo aceitero (Pongamia pinnata L. Pierre) por esquejes de raíz en diferentes épocas del año

2024-12-03T14:40:40+00:00

Pongamia pinnata L. Pierre is a multipurpose oil tree species, a source of renewable biofuel, in addition to being a recuperator of degraded soils due to its capacity to fix nitrogen. The most common form of propagation is through seeds, but there is little information available on its vegetative propagation, with asexual propagation being essential to maintain the characteristics of the mother plant and avoid variability. The objective of this work was to evaluate the incidence of substrate type, rooting hormone application and time of year on the vegetative propagation capacity of P. pinnata by means of root cuttings. The experiment was carried out in the Forest Nursery of the Faculty of Agricultural Sciences, National University of Asunción. A completely randomized design with factorial arrangement (3×2×2) was used, composed of 3 types of substrates, 2 times of the year, with and without application of IBA hormone. The variables evaluated were: percentage of survival and rooting, number of rootlets, rootlet length and rooting index. The data were subjected to analysis of variance (ANOVA) and in cases where significant differences were found, means were compared using Tukey’s test at 5% probability. The results indicate that Pongamia cuttings are not significantly influenced by the application of the IBA hormone and the type of substrate. However, they are significantly influenced by the time of year, with spring-summer being the best time for propagation by root cuttings, as demonstrated in this study.

Agronomic performance of five carrot varieties under protected environment and open field conditions in summer

2024-11-07T18:58:05+00:00

This experiment was conducted from January to April 2023, with the objective of evaluating the agronomic performance of five carrot varieties under both field and protected environment conditions. Variables assessed included: ambient temperature, plant stand, leaf count, leaf length and fresh weight, root fresh weight, length and diameter, as well as total, commercial, and non-commercial yields. Data underwent analysis of variance, and when significant differences were detected, means were compared using the Scott-Knott test at 5% probability error. Statistical analyses revealed no interaction among the evaluated variables, except for total yield. Significant differences between growing environments were found for all variables except total root yield. In open field conditions, superior means were observed for fresh weight and root length. The Nativa and Brasilia Irecê varieties achieved greater root mass and length, with means of 116.13 g and 98.37 g; 12.53 cm and 12.32 cm, respectively. Overall, the Nativa variety demonstrated superior performance in agronomic characteristics during summer conditions.

Características agronómicas y contenido de aceite de variedades de sésamo en el este de Paraguay

2024-09-17T18:40:35+00:00

In Paraguay, sesame holds an important social role in rural areas, as it is primarily cultivated by small-scale farmers. However, limited information is available on varieties with high yield potential. This study aimed to evaluate the agronomic traits and oil content of five varieties of Sesamum indicum L. Field trials were conducted in Saltos del Guairá and Ybyrarobana during the 2022/23 growing season. The experimental design was a randomized block design with five replications and five treatments corresponding to five sesame varieties (Inia, Negro, KO7, SH1, and Escoba) in each experiment. The evaluated characteristics were plant height, number of capsules, thousand-grain weight, grain yield, and oil percentage in
grains. The Escoba variety had the highest plant height (174.50 cm), and the Inia and Negro varieties had the highest thousand-kernel weight values of 3.20 and
3.02 g, respectively. No significant differences were observed in the number of capsules, productivity, or oil content among the varieties.

Productive performance, carcass and meat quality, and profitability of growing and finishing intact and castrated male cattle in feedlot

2025-03-04T17:38:43+00:00

With the objective of comparing the productive performance, carcass quality, meat quality, and profitability of growing and finishing intact male (IM) and castrated male (CM) cattle in feedlot, a study was conducted where, from a total of 242 recently weaned calves from the same production system, two groups were randomly formed: 128 castrated animals (T1) and 114 intact animals (T2). Both groups were housed in different pens for growing and finishing, treated under the same environmental conditions, health management, and nutrition. The productive variables evaluated were: weaning weight, weight at 138 days, and weight at the end of confinement, weight gain (WG), and average daily gain (ADG). Carcass and meat quality variables included: hot carcass weight (HCW), classification according to dentition and sex, grading according to fat coverage, conformation and bruising, compactness index (CI), ribeye area (REA), backfat thickness (BFT), and marbling score (MS). Finally, an economic analysis of the treatments was performed. The results show that IM cattle presented higher ADG (difference of 130 g/d), higher HCW (4.47 kg), and higher CI (0.07 points). Economically, the IM generated a net income of 31.4 USD higher. However, CM was superior in BFT (22.11%) and commercial quality, being mostly graded (88.89%) with the Premium grade, a category in which IM were not included.

Recognition of important weeds in juvenile stages in crops of Northeastern Argentina

2024-09-17T16:57:43+00:00

Agroecosystems in northeastern Argentina form important plant communities. Climbing weeds can become invasive. Monitoring and early detection of detrimental species can contribute to preventing infestations and are useful tools to achieve sustainable agriculture. The aim of the present study was to recognize, describe, and differentiate 12 weed species in juvenile stages. This was performed to facilitate monitoring and prevent weed invasion in yerba mate, tea, cassava, sweet potato, peanut, rice, and sunflower crops in 8 different locations in the provinces of Misiones, Corrientes, and Chaco. Vegetation surveys were carried out in different crops in 8 localities. Propagules were harvested from the most important weeds and stored in the refrigerator at 6°C. Subsequently, seeds and cuttings were placed in inert substrate with controlled humidity and at room temperature in plastic containers. A digital caliper and a standard flexometer were used. Likewise, photographs were taken with a smartphone and digital camera. Seedlings of 12 species were obtained, observed, morphologically described, illustrated, their parts were measured, their initial phenological stages were recorded, and they were taxonomically identified. A comparative table of the species studied, a dichotomous key for field recognition, and illustrations of the different taxa are presented. The morphological differences in seedling and young plant stages are important and sufficient to recognize these 12 species in the field and thus be able to choose IWM strategies aimed at the sustainability of agroecosystems in the northeastern region of Argentina.

Exploring the state of the art of tillage and its impact on soil quality and agricultural productivity: A critical review of the last 20 years

2024-11-07T17:22:19+00:00

Tillage has been a fundamental pillar in the establishment and evolution of agriculture over time. However, its impact on soil quality and agricultural productivity has received significant attention due to environmental challenges and the need for sustainable agriculture. This study assessed the state of the art on tillage practices and their influence on soil quality and agricultural productivity over the last 20 years, through an analysis of 92 articles from the Web of Science database. The results reveal a growing interest in the topic in the last decade, with notable contributions from the United States, China, Brazil, Canada, and India, focusing on conservation systems and their relationship with soil quality, organic matter, and agricultural productivity. The most frequently evaluated indicators include physical parameters (bulk density, penetration resistance, aggregates, porosity), chemical parameters (nitrogen, phosphorus, potassium, pH), and biological parameters (organic carbon, microbial biomass, enzymatic activities). The review suggests that conservation tillage systems tend to improve soil quality and crop productivity. However, some studies present contradictory results regarding soil physical quality and productivity, attributable to intrinsic factors. To better understand the impacts of tillage practices, it is crucial to conduct national-level research that considers the edaphoclimatic requirements of different crops, in order to identify the conditions under which conservation systems are most efficient for more sustainable and resilient agriculture.

Soybean (Glycine max L.) Performance and Physicochemical Properties of a Cambisol Under Two Crop Succession Systems

2024-08-08T19:28:42+00:00

The objective of this study was to evaluate the effect of two crop succession systems under no-till (NT) on the physical and chemical properties of the soil, as well as soybean yield, in a Cambisol. The experiment was conducted on a farm located in the Paratodo village, Pdte. Hayes, Paraguay, using a strip plot design with two Cover Crops (CC) as treatments: Megathyrsus maximus cv. Gatton Panic (Gatton) and a soybean/wheat/soybean succession (Wheat). The variables evaluated were aboveground biomass (BIOM), gravimetric moisture (GM), nitrogen concentration (NO3-N and NH4-N), bulk density (BD), penetration resistance (PR), infiltration rate (IR), soybean plant height, and soybean yield (Glycine max L.). Data were analyzed using analysis of variance with the Scott y Knott test at 5% significance, a t-test for two samples with equal variances, and trends were described through linear and polynomial regressions. The Gatton treatment demonstrated a greater capacity for retaining GM during the fallow and crop development stages, with average values throughout the trial of 19,2% for Gatton and 15,4% for Wheat. Additionally, Gatton recorded 2,09 times more BIOM at the start (11.311 vs. 5.390 kg ha⁻¹) and decomposed 1,88 times more crop residue, showing a higher daily decomposition rate compared to Wheat, with values of 12,7 kg ha⁻¹ day⁻¹ and 9,5 kg ha⁻¹ day⁻¹, respectively. BD was 3% lower in Gatton (1,32 g cm⁻³) compared to Wheat (1,36 g cm⁻³), and it increased with soil depth (25–50 cm). Wheat recorded critical PR values exceeding 3 MPa at sowing at depths of 5–15 cm and at the end of the trial at depths of 5–20 cm. Soybean plant height was 11.2% higher with Gatton (99,6 cm vs. 89,6 cm), which also achieved greater grain yield (3.336 kg ha⁻¹) compared to Wheat (2.929 kg ha⁻¹), with a difference of 13,9%. The production system based on a CC with Megathyrsus maximus cv. Gatton Panic improves the soil’s physicochemical properties and increases soybean yield.

Exploring the economic, environmental and social benefits of adopting Good Agricultural Practices

2024-10-04T20:08:19+00:00

Good Agricultural Practices (GAP) encompass three fundamental pillars: safety, environment, and quality. The main objective of this study was to analyze the economic, environmental, and social benefits of implementing GAP in soybean (Glycine max (L.) Merr.) production in the Naranjal district, located in Alto Paraná, Paraguay. Special attention was paid to analyzing the implementation of technologies, the challenges faced by producers, and the benefits they obtain from adopting these practices. A descriptive methodology with a quali-quantitative approach was employed, using surveys and semi-structured interviews. The benefits reported by producers after adopting GAP included: expense control, increased productivity, lower occupational risk, soil management and conservation, efficient pest management, reduced water pollution, and greater biodiversity and safety. The investment is considered profitable, being mainly directed towards improving structures. Six out of ten interviewed producers financed GAP with their own resources. The study delved into the economic, environmental, and social effects of applying GAP in soybean production, highlighting the need to address current challenges such as accessibility and incentives to promote its adoption and long-term benefits. It can be concluded that the adoption of GAP constitutes a beneficial strategy in economic, environmental, and social terms.

Funcionalidad de bancos comunitarios de semillas. Estudio de caso

2024-10-10T20:43:48+00:00

The agricultural, ecological, and social importance of seeds as genetic material allows them to be preserved in seed banks (SB), which must have adequate infrastructure, techniques, and methodologies to prevent the loss of seed viability. However, different communities play an important role in maintaining local seeds in community seed banks (CSB). This case study was conducted at the CSB of the Association of Agroecological Producers (APA) Azuay, located in the city of Cuenca, Ecuador, and aimed to determine the functionality of the APA Azuay CSB based on the current state of biodiversity and its influence on its members. A database was generated through information collected from the CSB and surveys conducted with CSB member-participants. The results showed that in the CSB, richness and Alpha biodiversity are limited, as both the Shannon-Weaver and Simpson indices showed medium-low range values; furthermore, APA Azuay members were already conserving seeds before becoming part of the CSB; however, the increased demand for popular crops such as corn and beans has led to genetic erosion. This study concludes that the CSB does not fully fulfill the functions for which it was created, either due to the low biodiversity of seeds or the little relevance it has had for its members; likewise, it is necessary to improve the infrastructure and appropriate techniques for the maintenance and conservation of genetic material.

Morphological Diversity of Common Bean (Phaseolus vulgaris L.) Germplasm Available at the Research Center for Family Agriculture of Choré, San Pedro, Paraguay

2024-06-26T16:59:07+00:00

Common bean (Phaseolus vulgaris L.) is one of the most consumed legumes in Paraguay, where both its green pods and dry grains can be utilized, thus benefiting the families that produce it through its added value. This work was carried out with the objective of evaluating the genetic diversity among common bean accessions from the germplasm bank of the Research Center for Family Agriculture (CIAF) of the Paraguayan Institute of Agricultural Technology (IPTA) based on morpho-agronomic data. Twenty common bean accessions were characterized; the variables considered were: plant height (cm), root length (cm), pod length (cm), pod diameter (cm), seed length (cm), seed width (cm), number of pods per plant, number of grains per pod, weight of 100 grains (g), pod yield (kg ha⁻¹), grain yield (kg ha⁻¹). Genetic diversity was obtained by dissimilarity measures based on the mean Euclidean distance; for group delimitation, the Unweighted Pair Group Method with Arithmetic mean (UPGMA) dendrogram method and Tocher’s optimization clustering were used. The study of the relative importance of characters in predicting genetic divergence was carried out based on the method proposed by Singh (1981). Groups with greater and lesser distances were formed. Grain yield was the characteristic that contributed most to the genetic distance between accessions. Genetic distances were observed among the accessions that can be explored for a genetic improvement program aimed at obtaining new cultivars with higher production, among other characteristics or selection criteria to address future threats and challenges of the crop.

Silage and corn grain productivity in succession to winter cover crops

2024-04-04T10:03:56+00:00

Corn is a crop of great importance and with a growing demand, but it requires a large amount of inputs. Therefore, cover crops preceding the corn crop are being evaluated in order to reduce the need for the use of chemical fertilizers. The objective of the present study was to evaluate the effect of different combinations and proportions of cover crop seeds on the productivity of silage and corn grains. The treatments implemented were: T1 - fallow; T2- Black oats-100%; T3- Vetch-100%; T4- 90% vetch + 10% black oats; T5- 75% Vetch + 25% Black oats and T6- 50% Vetch + 50% Black oats, in a randomized block experimental design with three replications. In all treatments, the green and dry mass of the cover crops were evaluated, in addition to the silage and grain productivity of the corn cultivated in the sequence. As a result, it was observed that T2 (100% oat) presented the highest amount of green and dry mass with values of 31,366 kg ha-11 and 5,420 kg ha-1, respectively. Regarding corn silage productivity, the predecessor treatments with vetch (T3 - 100%) and the combination of 90% vetch + 10% black oat (T4) and 75% vetch + 25% black oat (T5), presented the best results, with productivity of 62,775 kg ha-1; 62,451 kg ha-1; and 61,751 kg ha-1, respectively. These treatments also resulted in higher corn grain productivity, with values of 13,860 kg ha-1; 13,720 kg ha-1; and 13,650 kg ha-1, respectively. Therefore, single oats as a cover crop showed the best production of green and dry mass, but did not increase the productivity of silage and corn grains. However, the cultivation of single vetch (100%) or in intercropping (90% and 75%) with black oats resulted in greater productivity of silage and corn grains.

Production and profitability of mint (Mentha x piperita L.) with organic and inorganic soil covers

2024-02-06T17:39:49+00:00

Peppermint is a medicinal plant, being an interesting income item, however it is susceptible to water deficit, this being the main cause of the low yields of this item in plots without an irrigation system. With the objective of evaluating productive and economic parameters of peppermint with organic and inorganic soil covers, this research was carried out in a completely randomized design, composed of five treatments (soil without cover, black mulching, white mulching, rice husk and patcholí grass) and four repetitions, totaling 20 experimental units. The variables evaluated were: length of basal shoots, number of basal shoots and lateral shoots, yield of fresh and dry mass, cost/benefit profitability of each type of coverage. All means were subjected to the analysis of variance (ANAVA) and the means were compared by the Tukey Test at 5%. Regarding the length of basal shoots, the best results were with black mulching, followed by white mulching and patchouli grass; the greatest number of lateral shoots with 16.45 with the white mulching, on the other hand, in the number of basal shoots, the control had the highest number with 4.15. The white mulching presented a higher yield than the control for the fresh mass with 1,544 kg ha^-1 and dry mass of 628 kg ha^-1. When analyzing the profitability in the fresh mass of peppermint, the use of white mulching was more feasible and in dry mass they showed negative profitability for white mulching.

Endophytic colonization of local Trichoderma asperelloides strains in quinoa plants, Jujuy-Argentina

2024-02-05T19:34:22+00:00

The quinoa crop is affected by various diseases, with mildew (Peronospora variabilis Gaum) being the most important due to prevalence, severity and economic impact. Antagonistic endophytic fungi represent a sustainable option for the sanitary management of crops. The objective of the work was to determine the endophytic behavior of local strains of Trichoderma asperelloides in quinoa seedlings. The culture technique was used to re-isolate the fungus from root, stem and leaf sections at 15 and 30 daa and microscopic observation of histological sections to characterize the colonization of the fungus at 30 daa. The design defined the fixed effects: quinoa genotype (AMMA-18, RQ-252-18 and RQ-SAC-18), T. asperelloides strain: (T1, T15, T16); organ: root, stem, leaf, and evaluation time 15 and 30 daa. The highest occurrence of re-isolations was at 15 daa in RQ-252-18 from the three sections, followed by AMMA-2018 and RQ-SAC-18. Significant differences were recorded in the RQ-252-18/T16 interaction levels, with re-isolations from root and leaf being higher. At 30 daa, there were no differences between genotypes, but between type of organ, always superior in root. Re-isolation was dependent on the time since application and the genotype/strain combination. Intercellular colonization of fungal hyphae was observed in the epidermal tissue and stem and root cortex. The work expands the records of T. asperelloides as a quinoa endophyte for future multiple interaction studies with P. variabilis or other biotic and/or abiotic stress factors.