ABSTRACT Traditional agroecosystems (TA) are considered more resilient to climatic extremes due to higher crop diversity and agroecological approach. The TA of Tének were studied to evaluate their drought tolerance. Open-ended questionnaire surveys, field visits, and botanical collections, with the participation of local farmers, were considered. Cultivated plant diversity was analyzed using the Shannon-Wiener diversity index (H’), and the Morisita-Horn index (CMH) in ten different agroecosystems in April and August. Remote sensing methods included the triangular greenness index (TGI). Additionally, normalized difference vegetation index (NDVI) and standardized precipitation index (SPI) were determined, covering the period from 2013 to 2022. The cultivated plant richness (P > 0.5382) and their abundance (P > 0.3622) did not change from April to August considering the total analyzed parcels. However, differences between types of agroecosystems were observed because higher diversity corresponded to managed jungle (teʼlom) (Hʼ = 1.5-1.7), and some parcels cultivated with maize (milpa) (Hʼ = 1.02-1.54). Nevertheless, in August, lower similarity was observed in milpa (CMH = 0.23-0.87) due to the absence of maize (Zea mays L.) and other herbaceous annual crops. Landscape interconnection can be affirmed with TGI correlations obtained by comparison of different TA. The negative SPI values were associated with a decrease of NDVI, but Tének polyculture agroecosystems maintained higher NDVI values compared to rainfed monocropping during the analyzed period. Tének polyculture agroecosystems exhibited higher drought tolerance, although maize and other herbaceous plants are susceptible to disappearing during prolonged drought events, thereby increasing food insecurity.

Abstract Rural roads serve as pivotal conduits for the transportation of harvested crops to distribution hubs in Guarapuava-PR, a national agricultural focal point. This study evaluated the impact of incorporating brick kilns ashes(BKA) into the lateritic soil of an unpaved roadway. Mixtures of soil and BKA with three distinct granulometries were formulated, featuring substitution rates of 25%, 50%, and 75% ash relative to the total mixture mass,characterized in terms of: particle size distribution, liquid limit (LL), plastic limit (PL), and the optimum point on the compaction curve under modified energy conditions (optimal moisture content and maximum dry bulk density). Results revealed that BKA inclusion led to increases in LL, PL, OMC, CBR, alongside a reduction of MDD and expansion for the majority of mixtures, particularly within granulometry C1 at a 25% content. Finer ashes exhibited prominence in ISC and expansion outcomes. Substitutions of 75% BKA detrimentally affected geotechnical properties; however, granulometric stabilization with BKA proved feasible, particularly in soil-C2 mixtures designated for use as a sub-base. These mixtures met recommended LL and PL parameters, providing effective waste mitigation and presenting an alternative for soil improvement in pavement applications. GuarapuavaPR, GuarapuavaPR Guarapuava PR, PR Guarapuava-PR ashesBKA ashes(BKA roadway formulated 25 50 50% 75 masscharacterized mass characterized , (LL) (PL) optimal density. density . density) OMC CBR C outcomes properties however feasible soilC2 soilC C2 soil-C subbase. subbase sub base. base sub-base parameters applications 2 5 7 (LL (PL

Resumo Estradas vicinais são muito utilizadas para o escoamento da safra da área da colheita até os centros de distribuição na cidade de Guarapuava-PR, referência nacional no setor agrícola. Esta pesquisa avaliou o efeito da adição de cinzas de fornos de olarias (CFO) ao solo laterítico de uma estrada não pavimentada. Foram produzidas misturas de solo e CFO de três diferentes granulometrias, nos teores de substituição de 25%, 50% e 75%, de cinza em relação à massa total da mistura, caracterizadas quanto à:granulometria, limite de liquidez (LL), limite de plasticidade (LP) e ponto ótimo da curva de compactação sob energia modificada (umidade ótima (wot) e peso específico aparente seco máximo (ρdmáx)). Os resultados obtidos mostraram que a adição da CFO foi responsável por aumentos nos parâmetros LL, LP, wot, ISC, bem como pela redução do ρdmáx e da expansão da maioria das misturas, principalmente para a granulometria C1, no teor de 25%. Cinzas mais finas destacaram-se nos resultados de ISC e expansão. Substituições de 75% de CFO prejudicaram as propriedades geotécnicas, mas a estabilização granulométrica com CFO revelou-se viável, especialmente em misturas solo-C2 para utilização como sub-base, atendendo aos parâmetros recomendados de LL e LP, proporcionando mitigação de resíduos e uma alternativa para melhoramento de solos para pavimentação. GuarapuavaPR, GuarapuavaPR Guarapuava PR, PR Guarapuava-PR agrícola (CFO pavimentada granulometrias 25 25% 50 75 mistura àgranulometria, àgranulometria granulometria, à:granulometria , (LL) LP (LP umidade wot (wot ρdmáx. . (ρdmáx)) C1 C destacaramse destacaram se geotécnicas revelouse revelou viável soloC2 soloC C2 solo-C subbase, subbase sub base, base sub-base pavimentação 2 5 7 (LL (ρdmáx) (ρdmáx

Abstract Introduction. Weeds are one of the main problems in agricultural productivity due to their interactions with crops, such as alelopatic effects on germination. Objective. To evaluate the allelopathy of kikuyo grass (Cenchrus clandestinus) on the germination of beans (Phaseolus vulgaris L.) variety ICA Cerinza. Materials and methods. The study was conducted at the Quality Control Laboratory of the Universidad de Pamplona, Central Campus, Pamplona, Norte de Santander, Colombia, from May to August 2022. To each experimental unit (Petri dishe) with 12 been seeds, 6 mL of kikuyo aqueous extract (leaf, stem, and root) at three concentrations (1, 2.5, and 5 %), plus a control (0 %), were added, totaling 12 treatments. From day 0 to 12, the number of germinated seeds (NGS) was recorded, and the germination rate index (GRI) and germination index (IG) were calculated. The biomolecular profile of the aqueous extract was determined using the Fourier-transform spectroscopy. A completely randomized experimental design with a factorial arrangement (3x4), with repeated measures in each experimental unit, was employed. The intersuject factors were the organ type and concentration, while the intrasubject factor was the evaluation time (12 days). Results. Significant differences (p<0.001) were observed for NSG among treatments due to the concentration of the aqueous extract, as well as for IG, while GRI depended on the organ (p<0.05) and concentration (p<0.001), both negatively affected as the concentration increased. The infrared spectrum of the extract determined the presence of polyphenols, nitriles, and siloxanes. Conclusión. C. clandestinus affected NGS, GRI, and GI of P. vulgaris, with an allelopathic effect of the leaf aqueous extract at higher concentrations. Polyphenols, nitriles, and siloxanes associated with allelopathic effects were identified in the aqueous extracts.

Resumen Introducción. Las arvenses son uno de los principales problemas en la productividad agrícola, debido a interacciones con el cultivo, como efectos alelopáticos sobre la germinación. Objetivo. Evaluar la alelopatía del pasto kikuyo (Cenchrus clandestinus) en la germinación de frijol (Phaseolus vulgaris L.) variedad ICA Cerinza. Materiales y métodos. El estudio se realizó en el laboratorio de Control de Calidad de la Universidad de Pamplona, Campus Central, Pamplona, Norte de Santander, Colombia, en mayo-agosto 2022. A cada unidad experimental (caja de Petri) con doce semillas de frijol se le agregó 6 mL de extracto acuoso de kikuyo (hoja, tallo y raíz) en tres concentraciones (1, 2,5 y 5 %), más un testigo (0 %), para un total de doce tratamientos. En el lapso de 0 a 12 días, se registró el número de semillas germinadas (NSG), se calculó el índice de tasa de germinación (ITG) y el índice de germinación (IG), y se determinó el perfil biomolecular del extracto acuoso mediante la técnica de espectroscopia transformada de Fourier. Se utilizó un diseño experimental completamente al azar con arreglo factorial (3x4), con medidas repetidas en cada unidad experimental. Los factores intersujetos fueron el tipo de órgano y concentración, y el factor intrasujeto fue el tiempo (12 días) de evaluación. Resultados. Se observaron diferencias significativas (p<0,001) para NSG entre tratamientos por efecto de la concentración del extracto acuoso al igual que para IG, mientras que ITG dependió del órgano (p<0,05) y la concentración (p<0,001); ambos fueron afectados de forma negativa conforme aumentó la concentración. En el espectro infrarrojo del extracto se determinaron polifenoles, nitrilos y siloxanos. Conclusión. C. clandestinus afectó NSG, el ITG e IG de P. vulgaris, con efecto alelopático del extracto acuoso de hoja en mayor concentración. En los extractos acuosos se determinaron polifenoles, nitrilos y siloxanos, asociados a efecto alelopático.

Abstract Introduction. Pesticides are used to control pests and diseases in agricultural activities. Improper management of these products poses a potential risk to human health and the environment. Objective. To evaluate the (eco)toxicological pressure exerted by synthetic pesticides on tobacco crops (Nicotiana tabacum) in the province of Sancti Spíritus, Cuba. Materials and methods. A database from the Provincial Directorate of Plant Health for the period 2016-2019 was used, where the pesticides assigned to the province for this crop were compared with those reported by interviewed farmers. The dual indicator POCER was used to obtain the results, determining the pressure exerted by different pesticides and their harmful reference on humans and the environment. Results. The trend in pesticide consumption (summarized in tables and graphs) showed 50 % decrease, corresponding to the country’s crop protection policy. Farmers mentioned the use of authorized and unauthorized active ingredients in the conducted surveys, and sixteen high-risk active ingredients were detected in the analyzed samples. Evaluating the POCER results and analyzed samples, a significant (eco)toxicological pressure was observed on both the environment and human health, exerted by a group of high-toxicity active ingredients used in tobacco cultivation in the province. Conclusion. Using the dual indicator POCER provides an evaluation of the (eco)toxicological pressure exerted by synthetic pesticides used in the tobacco cultivation (Nicotiana tabacum) in the province of Sancti Spíritus, Cuba, for the study period.

Resumen Introducción. Los plaguicidas son utilizados para controlar las plagas y enfermedades en las actividades agrícolas. El manejo inadecuado de estos productos constituye un riesgo potencial para la salud humana y el medio ambiente. Objetivo. Evaluar la presión toxicológica (eco) ejercida por los plaguicidas sintéticos en los cultivos de tabaco (Nicotiana tabacum) en la provincia de Sancti Spíritus, Cuba. Materiales y métodos. Se utilizó una base de datos de la Dirección Provincial de Sanidad Vegetal para el período 2016-2019, donde se tomaron los plaguicidas asignados a la provincia para este cultivo y se compararon con los declarados por los agricultores entrevistados. Para la obtención de los resultados se utilizó el indicador dual POCER, que determinó la presión ejercida por los diferentes plaguicidas y su referencia nociva sobre el ser humano y el medio ambiente. Resultados. La tendencia del consumo de plaguicidas (resumida en tablas y gráficos) mostró una disminución del 50 %, que corresponde a la política de protección de los cultivos del país. Los agricultores mencionaron el uso de ingredientes activos autorizados y no autorizados en las encuestas realizadas, y en las muestras analizadas se detectaron dieciséis ingredientes activos de alto riesgo. Al evaluar los resultados de POCER y muestras analizadas se observó que existe una gran presión (eco)toxicológica tanto para el medio ambiente como para la salud humana ejercida por un grupo de ingredientes activos de alta toxicidad utilizados en el cultivo de tabaco de la provincia. Conclusión. Con la utilización del indicador dual POCER, se obtiene una evaluación de la presión (eco)toxicológica ejercida por los plaguicidas sintéticos utilizados en el cultivo del tabaco (Nicotiana tabacum) en la provincia de Sancti Spíritus, Cuba para el período de estudio.

Abstract Introduction. The soil and climatic conditions of Ecuador are ideal for rice cultivation, yields are higher than the world average, but agronomic management leads to an increase of cadmium in the soil, which can reach the grain by translocation, which affects its safety. Objetive. To evaluate the absorption of cadmium through the omission of macronutrients technique in six soils of Ecuador and its effect on the vegetative development of rice crops. Materials and methods. The trial was carried out at the Pichilingue Tropical Experimental Station of the National Institute of Agricultural Research, Ecuador, during 2018. Nine treatments were studied: 1) Without fertilization and without Cd (control 1), 2) without fertilization and with Cd (Control 2), 3) Complete fertilization and six omission treatments of one nutrient at a time, a completely randomized block design of experiments, divided plots and three repetitions was used. The variables evaluated were those related to the production of dry matter in the root and aerial part. For the comparison between means, the Tukey test was used (p<0.05). Results. Nutrients omissions (N and P) led to reduced Cd absorption, which decreased dry matter production, particularly in very acidic or alkaline soils such as in Sucumbíos (pH 4) and Guayas (pH 7, 9), respectively. Conclusions. The absorption of cadmium in rice plants was reduced to a greater extent with the omission of the macronutrients N and P, mainly in the soils of Sucumbíos, Los Ríos, El Oro and Manabí, the nutrient omission technique also affecting the production of dry matter and yields, also observing that a pH below 5 or higher than 7.9 affects the absorption of cadmium in the soils studied.

Resumen Introducción. Las condiciones edafoclimáticas del Ecuador son ideales para el cultivo del arroz, los rendimientos son mayores al promedio mundial, pero su manejo agronómico conlleva a un aumento de cadmio en el suelo, que puede llegar al grano por translocación, lo cual afectan su inocuidad. Objetivo. Evaluar la absorción de cadmio mediante la técnica de omisión de macronutrientes en seis suelos del Ecuador y su efecto sobre el desarrollo vegetativo del cultivo de arroz. Materiales y métodos. El ensayo se realizó en la Estación Experimental Tropical Pichilingue del Instituto Nacional de Investigaciones Agropecuarias, Ecuador, durante el año 2018. Se estudiaron nueve tratamientos 1) Sin fertilización y sin Cd (testigo 1), 2) sin fertilización y con Cd (Testigo 2), 3) Fertilización completa y seis tratamientos de omisión de un nutriente a la vez, se usó un diseño de experimentos de bloques completamente al azar, parcelas divididas y tres repeticiones. Las variables evaluadas fueron las relacionadas a la producción de materia seca en raíz y parte aérea. Para la comparación entre medias, se utilizó la prueba de Tukey (p<0,05). Resultados. Las omisiones de los nutrientes (N y P) llevaron a la reducción de la absorción del Cd, que disminuyó la producción de materia seca, en particular en los suelos muy ácidos o alcalinos como en Sucumbíos (pH 4) y Guayas (pH 7,9), respectivamente. Conclusiones. La absorción de cadmio en plantas de arroz se redujo en mayor medida con la omisión de los macronutrientes N y P, principalmente en los suelos de Sucumbíos, Los Ríos, El Oro y Manabí, afectando también la omisión de nutrientes a la producción de materia seca y los rendimientos, observándose además que un pH por debajo de 5 o superior a 7,9 afecta la absorción de cadmio en los suelos estudiados

ABSTRACT The use of bioactive compounds from macroalgae in agricultural formulations is an emerging technology with great potential to reduce dependence on synthetic agrochemicals. Currently, seaweed extracts are considered a sustainable resource due to their biodegradable nature. This review discusses their potential to replace or reduce a variety of synthetic molecules in economically important crops, such as synthetic nitrogen and phosphate fertilisers, synthetic hormone growth regulators, and organochlorine and organophosphate pesticides. Due to the presence of a wide range of bioactive substances already reported in certain algae, they are foreseen as good candidates for the production of plant bioformulations. In this sense, the commercial and biotechnological exploitation of macroalgae could benefit the local economy. However, despite the potential of algae, there is very little information on their total metabolomic or chemical content. This literature review summarises information proposing the use of the macroalgae Kappaphycus alvarezii, Acanthophora spicifera and Hypnea spinella in the Ecuadorian agricultural sector as an alternative for pesticide reduction.

RESUMEN El empleo de compuestos bioactivos extraídos de macroalgas en forma de formulaciones agrícolas representa una tecnología emergente con gran potencial para reducir la dependencia de agroquímicos sintéticos. Al presente, los extractos de algas marinas se consideran un recurso sostenible debido a su carácter biodegradable. En esta revisión se discute su potencial para reemplazar o reducir a una variedad de moléculas sintéticas en cultivos económicamente importantes, tales como fertilizantes sintéticos nitrogenados y fosfatados, reguladores del crecimiento hormonales sintéticos y plaguicidas organoclorados y organofosforados. Por la presencia de una extensa gama de sustancias bioactivas ya registradas en ciertas algas se prevén como buenos candidatos para la producción de bioformulaciones vegetales. En este sentido, el aprovechamiento comercial y biotecnológico de las macroalgas podría beneficiar la economía local. Sin embargo, pese a todo el potencial de las algas existe muy poca información de su contenido metabolómico o químico total. Esta revisión bibliográfica resume información que propone el uso de las macroalgas Kappaphycus. alvarezii, Acanthophora spicifera e Hypnea spinella dentro del sector agrícola ecuatoriano como alternativa para la reducción de pesticidas.

Summary: In different trials have shown that the use of both vermicompost (VC) and plastic mulch has favored the yield and productivity of a large number of crops. The purpose of our study was to compare synthetic fertilization vs the incorporation of VC on the development of triploid watermelon with plastic mulch in the spring-summer 2019 agricultural cycle at the experimental field of the Universidad Autónoma Agraria Antonio Narro. The treatments evaluated, each with three repetitions, were: exploratory application of VC, at a rate of 30 and 60 Mg ha-1, and as a control, the regional recommendation 240-120-00 ha-1 (N-P-K). The sowing was carried out in planting beds of 2 × 8 m (width and length, respectively) covered with black plastic. The sowing of the triploid watermelon seeds of the Crunchy Red variety, was carried out in Styrofoam trays with 200 cavities filled with Peat Moss. When the seedlings had two to three true leaves, they were transplanted 1.0 m apart on planting beds of 2 × 8 m (width and length, respectively) covered with black plastic. For the supply of water, drip irrigation was used. To evaluate the effect of the treatments, a completely randomized experimental design was used, the DMS0.05 test was applied for comparisons of the means. Due to the effect of the treatments evaluated, five of the variables studied: equatorial and polar diameters, pulp thickness, soluble solids and fruit weight presented highly significant differences, while yield registered a significant difference. The highest yield of 29 932 Mg ha-1 was recorded with the incorporation of 60 Mg ha-1 of VC confirming that this natural fertilizer was able to satisfy the nutritional needs of triploid watermelon without synthetic fertilization.

Resumen: En diferentes ensayos se ha evidenciado que el empleo, tanto del vermicompost (VC) como del acolchado plástico ha favorecido el rendimiento y la productividad de una gran cantidad de cultivos. El propósito del estudio fue equiparar la fertilización sintética vs la incorporación del VC sobre el desarrollo de la sandía triploide con acolchado plástico en el ciclo agrícola primavera-verano 2019, en el campo experimental de la Universidad Autónoma Agraria Antonio Narro. Los tratamientos evaluados, cada uno con tres repeticiones, fueron: aplicación exploratoria de VC, a razón de 30 y 60 Mg ha-1, y como testigo, la recomendación regional 240-120-00 ha-1 (N-P-K). La siembra de semillas de sandía triploide, variedad Crunchy Red, se realizó en bandejas de unicel de 200 cavidades, rellenas con Peat Moss, cuando las plántulas tuvieron de dos a tres hojas verdaderas se realizó el trasplante, colocándolas a 1.0 m, entre éstas, sobre camas de siembra, de 2 × 8 m (ancho y largo, respectivamente) cubiertas con plástico negro. Para el suministro de agua se utilizó riego por cintilla. Para evaluar el efecto de los tratamientos se utilizó un diseño experimental completamente al azar, mientras que para las comparaciones de las medias se aplicó la prueba DMS0.05. Debido al efecto de los tratamientos evaluados cinco de las variables estudiadas: diámetros polar y ecuatorial, espesor de pulpa, sólidos solubles y peso del fruto registraron diferencias altamente significativas, mientras que el rendimiento presentó diferencia significativa. El mayor rendimiento de 29 932 Mg ha-1 se registró con la aplicación de 60 Mg ha-1 de VC, confirmándose que este producto logró cubrir la demanda nutritiva de la sandía triploide sin fertilización sintética.

ABSTRACT Soil salinization, a rising issue globally, is a negative effect of the ever-changing climate, which has drawn attention to, and exacerbated problems related to soil degradation and the decline in wetland rice (Oryza sativa L.) production, leading to an unstable national economy. The use of rhizosphere inhabiting microorganisms (plant growth-promoting rhizobacteria, PGPR) is a viable method for boosting agricultural production on saline soils and reduce salt stress in rice crops. The objective of this study was to support the development of rice under salt stress by using a consortium of bacterial strains. ‘Pokkali’ rice plants inoculated with single Bacillus tequilensis and B. aryabhattai isolates were compared with consortium and non-inoculated plants while salinity was increased and by irrigation with tap water (control), 30 mM (5 dS m-1) and 60 mM (10 dS m-1) NaCl. The present study exhibited that inoculation of a mixed inoculum at 5 dS m-1 resulted in significantly higher dry weight of the shoots and roots of seedlings (9.29 and 1.24 g, respectively) which was due to the increased SPAD value, proline content (7.55 µmol g-1 FW), and antioxidant enzyme activity in the inoculated plants. The higher accumulation of osmoprotectants such as proline supported Na+ ion reduction and antioxidant enzymes such as ascorbate peroxidase and reduced polyphenol oxidase content protect against higher cellular damage, eventually leading to increase plant growth performance in saline soil. This study demonstrates some positive effects of the locally isolated salt tolerant consortium PGPR strains on the growth of rice plants under salt stress conditions.

ABSTRACT Fossil fuels, particularly oil, face sustainability challenges due to depletion and their role in increasing atmospheric CO2 levels, contributing to climate change and impacting global agriculture. Renewable energy sources like solar power offer a viable alternative. This study explores the feasibility of agro-photovoltaic (APV) systems, which integrate solar panels with agricultural land to generate electricity while cultivating crops. Specifically, the impact of APV systems on rice production and quality was investigated. Solar modules with a total capacity of 99.84 kW were installed on a 2580 m2 site, with two module configurations tested. Two rice (Oryza sativa L.) cultivars, Woonkwang and Saenuri, were transplanted and monitored for growth characteristics, chlorophyll content, and fluorescence, as well as yield and quality. Growth analysis of rice under APV systems showed minimal impact on plant height and tiller numbers, though chlorophyll content analysis indicated delayed leaf aging and extended maturation time. Rice yield decreased due to altered panicle and spikelet numbers. Quality analysis revealed changes in head rice rate and broken rice, stressing optimal harvest timing in APV systems. Shading conditions also affected physicochemical properties and taste profiles. Yields dropped by about 20% under APV systems, but the financial returns from electricity generation significantly outweighed the crop revenue loss. Despite the high initial installation costs and regulatory challenges, APV systems present a promising dual-use approach for enhancing farm income and promoting renewable energy. Continued research and investment are essential for optimizing APV systems and expanding their adoption.

Resumen Antecedentes: Los sistemas agrícolas tradicionales en Mesoamérica son adaptaciones ancestrales a los diversos y complejos ambientes. La tezcalera representa uno de ellos. Preguntas: ¿En qué contexto ambiental se desarrolla la tezcalera? ¿Cuáles son las prácticas de manejo que se llevan a cabo en la tezcalera?¿Cómo afectan a la riqueza, composición y abundancia de las arvenses? ¿Cómo influyen en la resiliencia del sistema agrícola, de los bosques tropicales secos y al mantenimiento de los recursos para la subsitencia? Especies de estudio: Arvenses en tezcaleras con diferente manejo. Sitio y años de estudio: Zumpahuacán, Estado de México, 2020-2021 Métodos: Entrevistas sobre prácticas de manejo de la tezcalera. Registro de la riqueza, composición y abundancia de malezas en parcelas con diferente historia de manejo. Resultados: Las tezcaleras se originan de la roza-tumba-quema y siguen diferentes rutas: el tlacolol-milsol-regeneración o potrero, y recientemente, cultivo de Agave. Registramos 161 morfoespecies y 45 familias botánicas; 95 % nativas de la selva baja caducifolia. Veinticinco son endémicas de la región del Balsas y 34 están en alguna categoría de riesgo. La riqueza y abundancia de las arvenses varió entre tezcaleras. La composición florística fue similar; 65 % tuvieron valor tangible o intangible. Conclusiones: La tezcalera es una unidad biocultural y un agroecosistema resiliente. Las prácticas tradicionales favorecen la riqueza y composición de las especies nativas. Los herbicidas y la introducción del cultivo de Agave desplazan a los cultivos tradicionales, poniendo en riesgo la agrobiodiversidad local.

Abstract Background: Traditional agricultural systems in Mesoamerica are adaptations of ancient farmers to the complex and varied environments. Tezcalera represents one of them. Questions: How is the environmental context under which the tezcalera develop? Which management practices are followed in tezcalera? How do these management practices affect weeds' richness, composition, and abundance? How do these management practices contribute to the resilience of the agricultural system, the tropical dry forests, and to the maintenance of subsistence resources? Studied species: Weeds growing in tezcaleras with different management. Study site and dates: Zumpahuacán, Estado de México, 2020-2021. Methods: Twenty-four collaborators were interviewed about the environmental, technological, and cultural aspects of tezcalera. We recorded weeds' richness, composition, and abundance in seven plots with different management histories. Results: Tezcaleras originate from the slash-burn process and follow different paths: tlacolol-milsol-shallow plot, potrero, and recently, Agave crop. We recorded 161 morphospecies from 45 botanical families; 95 % were native to tropical dry forests. Twenty-five species are endemic to the Balsas region, and thirty-four are at risk. Richness and abundance varied between tezcaleras, where tlacolol plots exhibited the highest values. Plant composition was similar; 65 % had intangible or tangible values. Conclusions: Tezcalera is a biocultural unit and a resilient agroecosystem. Traditional practices remain and positively impact the richness and composition of native weeds. The uncontrolled use of herbicides and the introduction of Agave crop are displacing traditional crops and modifying traditional practices, risking local agrobiodiversity.

ABSTRACT The software CIRS (Crop Irrigation Requirement and Scheduling) was developed to calculate the irrigation management of some crops produced in Guyana. The programming language used was Visual Basic within the Visual Studio platform. The interface was designed so that the user interacts with the software in a simple way. The program code was based on the classic irrigation management calculation procedure, but using single crop coefficients adjusted to the agro-meteorological conditions of Guyana, and estimating the physical properties of the soil according to texture, by mean a mathematical model recommended for use in the country. As a result, irrigation management parameters are obtained with greater precision to supply the water requirements of Guyana's agricultural crops.

RESUMEN Se elaboró el software CIRS (Crop Irrigation Requirement and Scheduling) para el cálculo del manejo de riego de algunos cultivos producidos en Guyana. El lenguaje de programación que se utilizó fue Visual Basic dentro de la plataforma Visual Studio. La interfaz fue diseñada para que el usuario interactúe con el software de manera sencilla. El código del programa se basó en el procedimiento clásico de cálculo del manejo del riego, pero utilizando coeficientes únicos de cultivo ajustados a las condiciones agro-meteorológicas de Guyana, y estimando las propiedades físicas del suelo según la textura, mediante un modelo matemático recomendado para usarlo en el país. Como resultado, se obtienen parámetros de manejo de riego con mayor precisión para satisfacer las demandas de agua de los cultivos agrícolas de Guyana.

Resumen La intervenciones institucionales que tuvieron lugar en las regiones andinas del noroeste argentino durante las últimas décadas han estado ancladas principalmente en estimular la producción de cultivos andinos mediante Procesos de Transición Agroecológica. A pesar de estos esfuerzos, la producción de cultivos andinos sigue resultando marginal en comparación a la horticultura comercial mediante agricultura convencional. En este artículo propongo aportar datos etnográficos que permitan poner en debate el diagnóstico apresurado según el cual ambos modelos productivos compiten entre sí en perjuicio de las prácticas más sustentables, para sostener que, en ocasiones, ambas formas de producción pueden constituir estrategias desplegadas por las mismas familias extensas con el fin de lograr dos objetivos complementarios, a saber: generar ingresos económicos suficientes para la reproducción doméstica, pero a la vez mantener vigente la producción de cultivos de valor afectivo y cultural, así como las parcelas agrícolas donde éstos son producidos, de mayor importancia ancestral pero menor rentabilidad, y que mediante este tipo de soluciones creativas son amparados de la excesiva agresividad de la agricultura convencional. Agroecológica esfuerzos convencional sustentables ocasiones complementarios saber doméstica cultural producidos rentabilidad

Abstract Over the last decades, institutional interventions in the Andean regions of northwest Argentina have been mainly focused on stimulating the production of Andean crops through Agroecological Transition Processes. Despite these efforts, Andean crop production remains marginal compared to conventional commercial horticulture. In this paper I intend to provide ethnographic data to challenge the premature diagnosis according to which both production models compete with each other to the disadvantage of more sustainable practices, in order to argue that, at times, both forms of production may constitute strategies deployed by the same extended families in order to achieve two complementary goals, namely: to generate sufficient economic income for domestic reproduction, but at the same time to maintain the production of crops of affective and cultural value, as well as the plots where they are produced, which are of greater ancestral importance but less profitable, and which through this type of creative solutions are protected from the excessive aggressiveness of conventional agriculture. decades Processes efforts horticulture practices that times goals namely reproduction value produced profitable agriculture

ABSTRACT The objective of this research was to evaluate the effect of inoculation and co-inoculation of rhizobia and Azospirillum brasilense combined with humic substances (HS) in growth promotion of Phaseolus lunatus (lima bean) and Leucaena leucocephala (leucaena). For this, experiments in a greenhouse with the cultivation of each plant species were carried out. A randomized complete block experimental design with five repetitions was followed. Plant seeds were sown and then inoculated with rhizobia and co-inoculated with A. brasilense. Subsequently, HS were added at the dose recommended by the manufacturer. In the experiments with both plants, control treatments with the addition of nitrogen (N) with or without HS were used. After 45 days, the shoot dry mass (SDM), root dry mass (RDM), shoot-accumulated N (Nac) and relative efficiency index (REI) were determined. In addition, the mass of dry nodules (MDN) in the lima bean plants and the number of nodules (NN) in leucaena plants were determined. The results showed that in the lima bean and leucaena plants there was a greater increase in SDM, RDM and Nac in treatments that received HS and co-inoculation with rhizobia and A. brasilense than in treatments that were inoculated only with rhizobia and HS and in treatments that received N and HS compared to addition of N and isolated inoculation of rhizobia. The combined application of HS and rhizobia in co-inoculation with A. brasilense had a greater effect on the increase of MDN in lima bean and NN in leucaena, than in treatments where only rhizobia with HS were added. These results indicate the existence of potential interaction of the use of HS with the co-inoculation of rhizobia and A. brasilense, showing promise for the production of sustainable agricultural crops.

RESUMEN El objetivo de esta investigación fue evaluar el efecto de la inoculación y co-inoculación de rizobios y Azospirillum brasilense combinados con sustancias húmicas (SH) en la promoción del crecimiento de Phaseolus lunatus (frijol lima) y Leucaena leucocephala (leucaena). Para ello se realizaron experimentos en invernadero con el cultivo de cada especie vegetal. Se siguió un diseño experimental de bloques completos al azar con cinco repeticiones. Se sembraron las semillas de plantas y luego se inocularon con rizobios y se coinocularon con A. brasilense. Posteriormente se agregaron SH con la dosis recomendada por el fabricante. En los experimentos con ambas plantas se utilizaron tratamientos control con adición de nitrógeno (N) con o sin SH. Después de 45 días, se determinó la masa seca de la parte aérea (MSPA), la masa seca de la raíz (MSR), el N acumulado en la parte aérea (Nac) y el índice de eficiencia relativa (IER). Además, se determinó la masa de nódulos secos (MNS) y en las plantas de leucaena el número de nódulos (NN). Los resultados mostraron que en las plantas de frijol lima y leucaena hubo un mayor aumento de MSPA, MSR y Nac en los tratamientos que recibieron SH y co-inoculación con rizobios y A. brasilense que en los tratamientos que fueron inoculados solo con rizobios y SH, y en tratamientos que recibieron N y SH en comparación con la adición de N y la inoculación aislada de rizobios. La aplicación combinada de SH y rizobios en co-inoculación con A. brasilense tuvo un mayor efecto en el aumento de MNS en frijol lima y NN en leucaena, seguido de los tratamientos donde solo se agregaron rizobios con SH. Estos resultados indican la existencia de una interacción potencial del uso de SH con la co-inoculación de rizobios y A. brasilense, lo que resulta prometedor para la producción de cultivos agrícolas sostenibles.

Abstract Endophytic fungi are plant symbiont microorganisms, diverse and abundant in tropical regions, with great potential as biocontrol agents of agricultural fungal diseases. The objective of the present work was to evaluate in vitro antifunfal activity of endophytic fungi associated with creole cultivars of Cucumis sativus and Lagenaria siceraria from Yucatán. The endophytic strains were isolated and identified from different organs, to be subjected to dual confrontations and antibiotic tests. Twenty species with antifungal effects against Corynespora cassiicola, Colletotrichum truncatum and Fusarium equiseti were identified, obtaining inhibition ranges of 17.72-100%, 16.51-91.55% and 4.64-91.89%, respectively. Aspergillus flavus, Lasiodiplodia pseudotheobromae and Trichoderma longibrachiatum exhibited the highest percentages of inhibition against the three phytopathogens. Likewise, these three species of endophytes demonstrated an antibiotic effect in their extracts, mainly inhibiting the growth of F. equiseti by up to 46.46%. The L. pseudotheobromae strain has characteristics that give it potential as an antifungal agent, so its applications and growth conditions should continue to be explored. This work represents a first effort to understand the diversity of endophytic fungi in native crops in the region.

Resumen Los hongos endófitos son microorganismos simbiontes de plantas, diversos y abundantes en regiones tropicales, con gran potencial como agentes biocontroladores de enfermedades fúngicas agrícolas. El objetivo del presente trabajo fue evaluar la actividad antifúngica in vitro de los hongos endófitos asociados con cultivares criollos de Cucumis sativus y Lagenaria siceraria de Yucatán. Las cepas endófitas fueron aisladas e identificadas de diferentes órganos de las plantas, para posteriormente ser sometidas a enfrentamientos duales y pruebas de antibiosis. Se identificaron 20 especies de hongos endófitos con efectos antifúngicos contra Corynespora cassiicola, Colletotrichum truncatum y Fusarium equiseti, obteniendo rangos de inhibición de 17.72-100%, 16.51-91.55% y 4.64-91.89%, respectivamente. Aspergillus flavus, Lasiodiplodia pseudotheobromae y Trichoderma longibrachiatum exhibieron los mayores porcentajes de inhibición contra los tres fitopatógenos. Así mismo, estas tres especies de endófitos demostraron un efecto antibiótico en sus extractos, al inhibir principalmente el crecimiento de F. equiseti hasta en un 46.46%. La cepa de L. pseudotheobromae tiene características que le confieren un potencial como agente antifúngico, por lo que se deberán seguir explorando sus aplicaciones y condiciones de crecimiento. Este trabajo representa un primer esfuerzo por conocer la diversidad de hogos endófitos en los cultivos criollos de la región.

Abstract In many agricultural crops, arbuscular mycorrhizal fungi co-exist and interact with saprophytic fungi. This study aimed to analyze the effects of two free-living phosphofungi on the growth of potatoes co-inoculated with Claroideoglomus claroideum. Micropropagated native potato plantlets were transferred to a sterile Andisol previously inoculated with C. claroideum and subsequently two saprophytic fungi. The treatments were: C. claroideum (T0), C. claroideum + Talaromyces pinophilus (T1), C. claroideum + Penicillium albidum (T2), and C. claroideum + T. pinophilus + P. albidum (T3). At harvest, the most relevant results show that in T3 the height, shoot dry weight, root length and P acquisition of the potato plants were increased. Therefore, dry weight and P absorbed by minitubers were enhanced two and three-fold, respectively, compared with T0, along with an increase in the length of the thinnest roots. It is concluded that co-inoculation of this fungal consortium could be an advantageous alternative to be used as a bioinoculant by potato tuber seed producers in sustainable agriculture.

Resumen En muchos cultivos agrícolas, los hongos micorrícicos arbusculares coexisten e interactúan con hongos saprófitos. El objetivo de este estudio fue analizar los efectos de dos fosfohongos de vida silvestre sobre el crecimiento de papas co-inoculadas con Claroideoglomus claroideum. Se trasfirieron plántulas de papa nativa micropropagadas a suelo Andisol estéril previamente inoculado con C. claroideum, y subsecuentemente con dos hongos saprófitos. Los tratamientos fueron: C. claroideum (T0), C. claroideum + Talaromyces pinophilus (T1), C. claroideum + Penicillium albidum (T2) y C. claroideum + T. pinophilus + P. albidum (T3). En la cosecha, los resultados más relevantes mostraron que el T3 incrementó la altura, el peso seco de los brotes, la longitud de las raíces y la absorción de P en las plántulas de papa. El peso seco y el P absorbido por los minitubérculos incrementaron al doble y triple, respectivamente, en comparación con el T0; además, aumentó la longitud de las raíces más delgadas. Se concluye que la co-inoculación de dicha asociación de hongos podría ser una alternativa favorable para su uso como bioinoculante por productores de semillas de tubérculos de papa en la agricultura sustentable.