ABSTRACT The search for more sustainable systems of rice cultivation, especially in relation to water use, has included the evaluation of more-efficient irrigation systems in addition to alternative water sources. The aim of this study was to conduct a phytosociological survey of weeds in rice crops irrigated by subsurface drip with different concentrations of treated dairy effluent, maintaining the soil moisture at saturation or field capacity. A pilot scale experiment was carried out in a protected environment using a randomised block design in a 5 x 2 factorial scheme, with four replications. The IAC 301 cultivar (Arborio rice) was chosen. The phytosociological surveys were carried out on four different dates, and considered the composition as well as the distribution of plant species in each of the applied treatments, using the importance value index (IVI) to evaluate the influence of each treatment. The results showed that cultivating irrigated rice, giving priority to water management, altered the ecology of invasive plants. Fourteen weed species were identified, distributed over 10 families. The effluent dose did not alter the incidence of invasive plants, and only at the final evaluation was there a reduction in the IVI value at effluent concentrations of 50% and 75%. For soil moisture, the highest IVI values occurred on the first two days of the survey under saturated conditions; this result was reversed closer to plant maturity, when the IVI values were higher at field capacity. cultivation use moreefficient efficient sources capacity scheme replications 30 Arborio chosen dates treatments (IVI treatment management plants identified 1 families 50 75 75% conditions maturity 3 7

ABSTRACT Soil water balance models can be a good option for studying crop growth and yield responses under different water supply levels. The aim of this study was to evaluate the effect of different irrigation strategies on sunflower yield and water productivity using field experiments and soil water balance simulations. Two field experiments were performed. In 2018/19, four irrigation strategies (aimed at maintaining soil available water at 80, 70, 60, and 50% of total available water) were evaluated. In 2020/21 an irrigated and a rain-fed treatment were evaluated. The SIMDualKc model was calibrated and validated to simulate soil water balance and derive the dual coefficients using plant variables from field observations. Grain yield was highest in the treatment maintained at 70% of total available water in Study I, suggesting that a water replenishment reduction strategy may be an alternative to irrigation management, especially in locations where water is scarce. The statistical indicators showed good performance of the model in simulating the water available in the soil, with the coefficient of determination > 0.90 and modeling efficiency above 0.86 for all cases. The study allowed the calibration of the single and basal crop coefficients of sunflower, which are important parameters for irrigation management. levels simulations performed 201819 2018 19 2018/19 aimed 80 70 60 50 evaluated 202021 2020 21 2020/2 rainfed rain fed observations I management scarce 090 0 90 0.9 086 86 0.8 cases 20181 201 1 2018/1 8 7 6 5 20202 202 2 2020/ 09 9 0. 08 20 2018/

RESUMO Os modelos de balanço hídrico do solo podem ser uma boa opção para estudar o crescimento das culturas e as respostas de rendimento sob diferentes níveis de fornecimento de água. O objetivo deste estudo foi avaliar os efeitos de diferentes estratégias de irrigação na produtividade do girassol e na produtividade da água usando experimentos de campo e simulações de balanço hídrico do solo. Dois experimentos de campo foram realizados. Em 2018/19, foram utilizadas quatro estratégias de irrigação (mantida a água disponível no solo em 80, 70, 60 e 50% da água total disponível). Em 2020/21 foi utilizado um tratamento irrigado e de sequeiro. O modelo SIMDualKc foi calibrado e validado para simular o balanço hídrico do solo e derivar os coeficientes duais usando variáveis da planta a partir de observações de campo. A produtividade de grãos foi maior no tratamento mantido a 70% do total de água disponível no Estudo I, sugerindo que a redução da reposição de água pode ser uma alternativa para o manejo da irrigação, principalmente em locais onde a água é escassa. Os indicadores estatísticos mostraram um bom desempenho do modelo na simulação da água disponível no solo, com coeficiente de determinação > 0,90 e eficiência de modelagem acima de 0,86 para todos os casos. O estudo permitiu a calibração do coeficiente de cultura simples e basal do girassol, que são parâmetros importantes para o manejo da irrigação. realizados 201819 2018 19 2018/19 mantida 80 70 6 50 disponível. . disponível) 202021 2020 21 2020/2 sequeiro I escassa 090 0 90 0,9 086 86 0,8 casos 20181 201 1 2018/1 8 7 5 20202 202 2 2020/ 09 9 0, 08 20 2018/

Abstract In order to widen the application fields of thermosetting composites, this research aims to identify the bioresins and biofibers more resistant to weathering, enabling their use outdoors. Data were collected from experimental research on composites made from synthetic or plant-derived matrix with plant or hybrid fibers, and using various molding processes, reinforcement geometries, alignment and treatment of fibers and fiber/matrix fractions. The investigation searched for researches that studied the composites tensile and flexural strengths; their water absorption in 24 hours of immersion and until saturation; and their retention of mechanical strength after aging. The effect of matrix and fiber types and their fractions on these properties was studied. Results indicate that composites with plant-derived matrix absorb less water in 24h, and that composites with flax, sisal or hemp have the lowest water absorption at saturation and the greater retention of tensile strength after aging. In other words, apparently these composites are less prone to weathering and thus have potential for outdoor use. However, regardless of the fiber type, as its content increases, the retention of flexural strength of composites decreases, limiting their usage in some applications. outdoors plantderived derived processes geometries fibermatrix strengths 2 aging 24h h flax words However type increases decreases applications

Resumo Buscando ampliar a aplicação dos compósitos termorrígidos, esta pesquisa objetiva identificar as bioresinas e biofibras mais resistentes às intempéries, contribuindopara seu uso externo. Foram levantadas pesquisas experimentais sobre compósitos com matriz sintética ou vegetal e fibras vegetais ou híbridas, com diferentes processos de moldagem, geometrias de reforço, alinhamento e tratamento das fibras e frações fibras/matriz. Buscou-se trabalhos que estudaram as resistências à tração e à flexão; a absorção de água dos compósitos em 24h de imersão e até a saturação; e sua retenção da resistência mecânica após envelhecimento. Investigou-se a influência do tipo de matriz e de fibra e de suas frações nessas propriedades. Resultados indicam que compósitos de matriz vegetal absorvem menos água em 24h, e que compósitos com linho, sisal ou cânhamo possuem a menor absorção de água na saturação e maior retenção da resistência à tração após o envelhecimento. Isto é, aparentemente esses compósitos sofrem menos danos devido às intempéries, possuindo maior potencial para uso externo. Mas, independentemente da fibra, conforme sua quantidade aumenta, diminui a retenção da resistência à flexão dos compósitos, limitando sua aplicação. termorrígidos intempéries externo híbridas moldagem reforço fibrasmatriz fibras/matriz Buscouse Buscou se h envelhecimento Investigouse Investigou propriedades linho é Mas aumenta

Abstract Introduction. Heavy metal pollution is a growing problem due to human activities. Plants can remove, destroy, or transform contaminants from soil, water, and air. By using plant growth regulators and chelating agents, heavy metal toxicity can be reduced. Objective. To evaluate the effect of applying a mixture of oligogalacturonides on peroxidase activity and the contents of malondialdehyde, total protein, and chlorophylls in tomato plants (Solanum lycopersicum L.) var. Amalia subjected to high levels of heavy metals. Materials and methods. Soil contaminated with Cu, Cd, and Fe was collected from the Adalberto Vidal White Ceramic Company in Mayabeque, Cuba, in 2020. The experiment was conducted in 7 kg capacity bags using tomato plants, under semi-controlled conditions at the Instituto Nacional de Ciencias Agrícolas (INCA), with a completely randomized experimental design with each treatment having ten replicates. The treatments with the oligogalacturonides (Ogal) were soil application (30 mg kg-1); foliar spray (20 mg L-1), the combination of these application forms, and a control. Peroxidase activity and the contents of malondialdehyde, total protein, and chlorophylls were determined at 35 and 56 days after the plant’s emergence. Results. The effect of Cu, Cd, and Fe on the seedlings was attenuated by all the use of the Ogal mixture variants use, indicating that they have developed adaptation mechanisms to high metal concentrations which allows to withstand abiotic stress. Conclusions. The Ogal mixture attenuated the effect of heavy metals on peroxidase activity, malondialdehyde content, total proteins, and chlorophylls in Amalia tomato plants.

Resumen Introducción. La contaminación por metales pesados es un problema que ha ido en aumento, debido a las actividades antrópicas. Las plantas pueden eliminar, destruir o transformar contaminantes del suelo, agua y aire. Con el empleo de reguladores del crecimiento vegetal y agentes quelantes se puede reducir la toxicidad por metales pesados. Objetivo. Evaluar el efecto de la aplicación de una mezcla de oligogalacturónidos sobre la actividad peroxidasa y los contenidos de malondialdehido, proteinas totales y clorofilas, en plantas de tomate (Solanum lycopersicum L.) var. Amalia sometidas a altos niveles de metales pesados. Materiales y métodos. Se colectó suelo contaminado con Cu, Cd y el Fe, en la Empresa cerámica blanca Adalberto Vidal de Mayabeque, Cuba en el año 2020. El experimento se desarrolló en bolsas de 7 kg de capacidad y se utilizaron plantas de tomate, en condiciones semi controladas en áreas del Instituto Nacional de Ciencias Agrícolas (INCA), con un diseño experimental completamente aleatorizado con siete tratamientos y diez réplicas. Los tratamientos del producto a base de oligogalacturónidos (Ogal) fueron: aplicación al suelo (30 mg kg-1); aspersión foliar (20 mg L-1), la combinación de estas formas de aplicación y un testigo. A los 35 y 56 días de emergidas las plantas, se determinó la actividad peroxidasa y los contenidos de malondialdehido, proteinas totales y clorofilas. Resultados. El efecto que provocan el Cu, Cd y el Fe en las plántulas, fue atenuado por todas las variantes de uso de la mezcla Ogal, por lo que las mismas han desarrollado mecanismos de adaptación ante las altas concentraciones metálicas que le permiten subsistir al estrés abiótico. Conclusiones. La mezcla de Ogal atenuó el efecto que provocan los metales pesados en la actividad peroxidasa, el contenido malondialdehido, proteínas totales y clorofilas en plantas de tomate var. Amalia.

Abstract Introduction. Corn is one of the oldest known food grains. With climate change and frequent and severe droughts, the water available in the soil will be considerably reduced. Water deficit affects maize crop development to varying degrees, and sensitivity to this stress varies at different development stages. Objective. To identify the phenological stages most sensitive to water deficit in maize. Materials and methods. The experiment was conducted during two growing seasons in 2020 and 2021 in El Ejido, Los Santos province, Panama, under semi-controlled conditions in the greenhouse facilities of the Instituto Coronel Segundo de Villarreal. The commercial corn hybrid ADV-9293 was used and agronomic management was carried out according to the recommendations of the Institute for Agricultural Innovation of Panamá (IDIAP). Plant height, leaf length and width, stem diameter, biomass and yield components, such as number of rows per ear, number of grains per row and 100-grain mass, were determined throughout the crop cycle. Soil moisture was also determined by the gravimetric method. Water deficit at different stages was generated by drought simulation. Results. The grain yields of the control were higher than the different treatments evaluated with 12.83 t ha-1, followed by the treatment with grain filling stress with 10.31 t ha-1. Two periods were determined to be more sensitive to water deficit; these were the stages from 20 to 35 and 40 to 55 days after planting. Water deficit in the different phenological stages of the crop had a negative impact on the relative chlorophyll content. Conclusion. The pre-flowering and flowering stages were more sensitive to water deficiency in maize.

Resumen Introducción. El maíz es uno de los granos alimenticios más antiguos conocido. Con el cambio climático y las sequías severas y frecuentes, se reducirá en gran medida el agua disponible en el suelo. El déficit hídrico afecta en diversos grados el desarrollo del cultivo de maíz y la sensibilidad a este estrés varía en las diferentes etapas de desarrollo. Objetivo. Identificar las etapas fenológicas más sensibles al déficit hídrico en el cultivo de maíz. Materiales y métodos. El experimento se realizó durante dos ciclos en los años 2020 y 2021 en El Ejido, Provincia de Los Santos, Panamá. Se desarrolló bajo condiciones semicontroladas en la casa de cultivo del Instituto Coronel Segundo de Villarreal. Se utilizó el híbrido de maíz comercial ADV-9293. El manejo agronómico se realizó según las recomendaciones del Instituto de Innovación Agropecuaria de Panamá (IDIAP). Durante todo el ciclo del cultivo, se determinaron las variables altura de planta, largo y ancho de hojas, diámetro del tallo, biomasa y los componentes del rendimiento como número de hileras por mazorca, número de granos por hilera y peso de cien granos. También, se determinó la humedad del suelo por el método gravimétrico. El déficit hídrico en distintas etapas se generó a través de la simulación de sequía. Resultados. El rendimiento de grano del testigo superó los diferentes tratamientos evaluados con 12,83 t ha-1, seguido por el tratamiento con estrés en el llenado de grano con 10,31 t ha-1. Se determinaron dos períodos más sensibles al déficit hídrico; los cuales son las etapas comprendidas desde los 20 a 35 y 40 a 55 dds. El déficit hídrico, durante las diferentes etapas fenológicas del cultivo, tuvo un impacto negativo en el contenido relativo de clorofilas. Conclusión. Las etapas de prefloración y floración resultaron más sensibles a la deficiencia hídrica en el cultivo del maíz.

ABSTRACT Potassium is a nutrient with the potential to increase plant tolerance to salt stress. The aim of this study was to evaluate the production and quality of kale subjected to salt stress and potassium concentrations in a protected environment. The experimental design was in split plots, with plots composed of five nutrient solutions (control treatment, S1 - standard nutrient solution prepared in low-salinity water, 0.5 dS m-1 (500 mg L-1 of KNO3), and four nutrient solutions prepared in brackish waters (3.5 dS m-1) containing four concentrations of KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1,000 mg L-1), and subplots represented by two leaf kale cultivars (Manteiga and Manteiga da Geórgia). Leaf production variables and post-harvest physical and chemical qualities were evaluated. The saline nutrient solution with the addition of NaCl (S2) reduced production but did not reduce the post-harvest quality of kale. The extra addition of KNO3 at 25% (S3) was efficient in reducing the deleterious effects of salt stress on the variables leaf length, leaf area, leaf production, and number of bunches. The cv. Manteiga da Geórgia was more tolerant to salt stress than the cv. Manteiga. environment control treatment S lowsalinity low salinity water 05 0 5 0. m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3.5 35 3 (3. S2 (S 50 L1, 1, 62 75 1000 000 1,00 L-1) Geórgia. . Geórgia) postharvest post harvest evaluated 25 (S3 length area bunches cv (5 3. (3 6 7 100 00 1,0 2 ( 10

RESUMO O potássio é um nutriente com potencial para aumentar a tolerância das plantas ao estresse salino. O objetivo deste estudo foi avaliar a produção e a qualidade da couve submetida ao estresse salino e às concentrações de potássio em ambiente protegido. O delineamento experimental adotado foi em parcela subdivididas, sendo as parcelas compostas por cinco soluções nutritivas (tratamento controle, S1 - solução nutritiva padrão usando água de baixa salinidade, 0,5 dS m-1 (500 mg L-1 de KNO3), e quatro soluções nutritivas preparadas em águas salobras (3,5 dS m-1) contendo quatro concentrações de KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1.000 mg L-1). As subparcelas foram representadas por duas cultivares de couve folha (Manteiga e Manteiga da Geórgia). Foram avaliadas as variáveis de produção de folhas e qualidades físicas e químicas pós-colheita. A solução nutritiva salinizada com adição de NaCl (S2) reduziu a produção, mas não reduziu a qualidade pós-colheita da couve folha. A adição extra de KNO3 em 25% (S3) foi eficiente para reduzir o efeito deletério do estresse salino sobre as variáveis comprimento de folha, área foliar, produção e número de maços. A cv. Manteiga da Geórgia se mostrou mais tolerante ao estresse salino que a cv. Manteiga. protegido subdivididas tratamento controle S salinidade 05 0 5 0, m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3,5 35 3 (3, S2 (S 50 L1, 1, 62 75 1000 000 1.00 L1. . L-1) Geórgia. Geórgia) póscolheita. póscolheita pós colheita. colheita 25 (S3 foliar maços cv (5 3, (3 6 7 100 00 1.0 2 ( 10 1.

ABSTRACT Maize (Zea mays L.) is highly sensitive to salt stress, which poses a threat to its production, especially with predicted increases in salinity due to climate change. Enhancing salt tolerance in maize is critical to mitigating these adverse effects, sustaining its production, and ensuring global food security. This study aimed to evaluate the effects of exogenously applied lipoic acid or Si, alone or in integration with soil application of vermicompost-tea on physio-biochemical components, antioxidant defense systems, growth, and yield of maize plants exposed to salt stress. The application of vermicompost-tea was carried out as a soil treatment incorporated into irrigation water at a concentration of 200 L ha-1, and administered in three equal doses in irrigation water within the last 10 min of drip irrigation. Silicon was applied at a rate of 6 mM using potassium silicate and lipoic acid was applied at 0.1 mM. Silicon and lipoic acid were applied three times at 25, 40, and 55 d after planting. The results indicated that the integrative application of soil-based vermicompost-tea with exogenously applied Si or lipoic acid significantly enhanced all studied parameters. Specifically, the combination of Si with vermicompost-tea exhibited the highest improvement percentage compared to untreated control in chlorophyll a (60.3%), chlorophyll b (72.7%), carotenoids (69.9%), net photosynthetic rate (111%), transpiration rate (134%), stomatal conductance (129.5%), relative water content (28.4%), membrane stability index (44.3%), N (33.4%), P (71.9%), K (39.7%), Ca (89.9%), K/Na (81.2%), total soluble sugars (63.7%), proline (60.1%), ascorbate (44.4%), glutathione (83.5%), and α-tocopherol (72.1%). These positive effects were reflected in enhancing yield traits under salt-affected soil conditions by enhancing plant height (25.1%), number of grains per row (43.3%), number of rows per ear (26.7%), 1000‐grain weight (25.9%), grain yield (45.4%), and biological yield (42.8%) compared to untreated control.

ABSTRACT Red chili pepper Capsicum annuum L. var. annuum plants are one of the fruity vegetable types that are often cultivated in riparian tropical wetlands but are constrained by water stress such as waterlogging during rainy season and drought in dry season. The aim of this research was to evaluate the growth and morpho-physiological responses of red chili pepper cultivars subjected to waterlogging and drought stress conditions. The experiment was carried out in a strip-plot design with two factors. The first factor was three water stress treatments, namely control (field capacity), waterlogging, and drought. The second factor was six cultivars of Indonesian red chili pepper. The findings indicated that both waterlogging and drought stress had a detrimental impact on the reduction of the growth parameters of red chili pepper such as root, shoot and total dry weight. Chili pepper defended its root weights in response to drought stress (0.653 g plant-1) whereas it preserved shoot weight in response to waterlogging (0.913 g plant-1). In the morphological characters, chili pepper exhibited an increase in specific leaf area expansion in response to both waterlogging (150.82 cm2) and drought (188.82 cm2) compared to control (140.91 cm2), but decreased specific leaf weight during stresses and recovered after 7 d in waterlogging. Leaf chlorophyll content (SPAD) and leaf relative water content (LRWC), as physiological characteristics, also experienced a decline during exposure to both waterlogging and drought during 8 d; yet, SPAD and LRWC able to recover completely at 7 d after waterlogging and drought treatment were terminated.

Abstract The use of alternative tree and shrub species such as Hibiscus rosa sinensis L, for feeding ruminants, can provide high amounts of feed biomass and high protein content. The most commonly used propagation methods for the production of seedlings of this species are by grafting, layering and cuttings, with the latter method standing out, because it allows obtaining a greater number of seedlings per branch in less time. The objective of the research was to evaluate the effect of alternative rooting agents on wasp flower (H. rosa-sinensis L.) cuttings, under nursery conditions. Five rooting agents were evaluated consisting of Aloe vera, cinnamon, Aloe + molasses + egg (A+M+E), Moringa oleífera and the antagonistic fungus Trichoderma sp, plus a control consisting of the addition of water. The variables evaluated were number of roots per plant, root length, number of regrowths, fresh root weight per plant, dry root weight per plant, root biomass and survival percentage. The data were organized in a Microsoft Excel 2013 spreadsheet, then analyzed in the statistical program InfoStat 2020. The treatment with Trichoderma sp favors the vegetative growth of H. rosa-sinensis, followed by the A+M+E, Moringa and cinnamon treatments. The treatments with the highest percentage of survival were Moringa, cinnamon, Aloe, and Trichoderma sp, considered as excellent, while the A+M+H and control treatments were considered good.

Resumen El uso de las especies alternativas de árboles y arbustos como son Hibiscus rosa sinensis L, para la alimentación de rumiantes, puede proporcionar altas cantidades de biomasa alimenticia y alto contenido de proteína. Los métodos de propagación más utilizados para la producción de plántulas de esta especie son por injerto, acodo y esquejes, destacándose este último método, porque permite obtener un mayor número de plántulas por rama en menor tiempo. El objetivo de la investigación fue evaluar el efecto de enraizadores alternativos sobre esquejes de flor de avispa (H. rosa-sinensis L.), bajo condiciones de vivero. Se evaluaron cinco enraizadores que consistieron en aloe vera, canela, aloe + melaza + huevo (A+M+H), Moringa oleifera y el hongo antagonista Trichoderma sp, además de un testigo que consistió en la adición de agua. Las variables evaluadas fueron número de raíces por planta, longitud de raíces, número de rebrotes, peso fresco de raíz por planta, peso seco de raíz por planta, biomasa de raíces y porcentaje de sobrevivencia. Los datos fueron organizados en una hoja de cálculo de Microsoft Excel 2013, posteriormente fueron analizados en el programa estadístico InfoStat 2020. El tratamiento con Trichoderma sp favorece el crecimiento vegetativo de H. rosa-sinensis, seguido de los tratamientos A+M+H, Moringa y canela. Los tratamientos con mayor porcentaje de sobrevivencia fueron Moringa, canela, aloe y Trichoderma sp, considerados como excelentes, mientras que los tratamientos A+M+H y testigo fueron considerados buenos.

Abstract The excessive use of petroleum-based plastics creates a serious problem of environmental pollution, for this reason, this work proposes the production of bioplastic films based on cellulose extracted from leaves and stems of Ricinus communis L. (castor oil plant). The project was carried out in 2022 in the state of Michoacán, Mexico. The bioplastic was obtained in two stages, first the extraction of cellulose is carried out by an alkaline treatment at 80 °C, then, the cellulose obtained is mixed with water, glycerin, and acetic acid for the formation of the bioplastic film by the casting method. With the above procedure, uniform films with a thickness of 0.12 mm were obtained. Regarding the tensile strength, a maximum value of 7.1 MPa was found, as the amount of glycerin increases, the tensile strength increases. Through scanning electron microscopy analysis, it was observed that bioplastic films with 5% glycerin exhibit more uniform and homogeneous textures. The castor oil plant can be used not only to obtain oil but also to obtain plastics from sources alternative to petroleum, which would favor its cultivation in Michoacán.

Resumen El uso excesivo de plásticos elaborados con base de petróleo crea un grave problema de contaminación ambiental, por tal motivo, en el presente trabajo se propone la elaboración de películas de bioplástico a base de celulosa extraída de hojas y tallos de Ricinus communis L. (higuerilla). El proyecto se llevó a cabo en el año 2022 en el estado de Michoacán, México. El bioplástico se obtuvo en dos etapas, primero se lleva a cabo la extracción de celulosa mediante un tratamiento alcalino a 80 °C, posteriormente, la celulosa obtenida se mezcla con agua, glicerina y ácido acético para la formación de la película de bioplástico mediante el método de casting. Con el procedimiento anterior se obtuvieron películas uniformes con un espesor de 0.12 mm. En cuanto a la resistencia a la tracción se encontró un valor máximo de 7.1 MPa, al incrementar la cantidad de glicerina, aumenta la resistencia a la tensión. Mediante el análisis de microscopia electrónica de barrido, se observó que las películas del bioplástico con un 5% de glicerina exhiben texturas más uniformes y homogéneas. La higuerilla se puede aprovechar no solo para la obtención de aceite sino también para obtener plásticos de fuentes alternas al petróleo, lo que se favorecería su cultivo en Michoacán.

ABSTRACT The paper analyzes the quality of the water supplied by the potable water treatment plant Altos of Quintero to the city of Santiago de Cuba through the study of five consumers. The quality of the parameters analyzed was determined for pH, color, turbidity, residual free chlorine and determination of total and fecal coliforms, resulting in La Colonia, La Cervecería Hatuey and the Combined Milk, which residual free chlorine and turbidity are outside the norm in some occasions. The effects of the quality of drinking water coming from the potabilizer were mainly the deterioration of the infrastructure of the supply networks and poor storage conditions of the liquid in the above mentioned institutions. Options are presented to ensure that water quality is maintained in the different consumption centers and a predictable model is proposed that allows the maximum time that guarantees the minimum level of allowable residual chlorine that a consumer source should have.

RESUMEN El trabajo analiza la calidad del agua que suministra la potabilizadora Altos de Quintero a la ciudad de Santiago de Cuba mediante el estudio de cinco consumidores. Al agua de los seis centros analizados se les determinó su calidad por la medición de los parámetros: pH, color, turbidez, cloro libre residual y determinación de coliformes totales y fecales, resultando La Colonia, La Cervecería Hatuey y el Combinado Lácteo las entidades en las cuales el cloro libre residual y la turbidez se encuentran fuera de norma en algunas ocasiones. Las afectaciones de la calidad del agua potable procedente de la potabilizadora se deben fundamentalmente al deterioro de la infraestructura de las redes de abastecimiento y a las malas condiciones de almacenamiento del líquido en las instituciones antes mencionadas. Se presentan opciones para garantizar que se mantenga la calidad del agua en los diferentes centros de consumo y se propone un modelo predictivo que posibilita determinar el tiempo máximo que garantiza el mínimo nivel de cloro residual libre permisible que debe disponer una fuente consumidora.

ABSTRACT Peanut (Arachis hypogaea) is an important agricultural crop in Brazil, considered one of the most important oilseed crops cultivated. The use of fertilizer-solubilizing bacteria can mitigate salt stress. The objective of this study was to evaluate the gas exchange, growth, and water use efficiency of the peanut crop irrigated with brackish water under phosphate fertilization and inoculated with bacteria of the genus Bacillus sp. The experimental design used in this study was completely randomized, in a 4 × 2 × 2 factorial scheme, with 5 replicates, referring to the forms of fertilization (F1 - 0% phosphorus, F2 - 50% phosphorus, F3 - 100% phosphorus, and F4 - bovine biofertilizer), presence and absence of the inoculant and two levels of electrical conductivity of the irrigation water (ECw - 0.3 and 4.0 dS m-1). Fertilization with organic fertilizer (100% biofertilizer) and mineral fertilizer (50 and 100% phosphorus) associated with Bacillus sp. mitigated the damage caused by salt stress and promoted greater water use efficiency, chlorophyll index, internal CO2 concentration and stem diameter. The control treatment (without phosphate fertilization and without salt stress) and the application of Bacillus sp. promoted greater performance in net photosynthesis, transpiration rate, stomatal conductance, and plant height in peanut plants. Arachis hypogaea Brazil cultivated fertilizersolubilizing solubilizing exchange growth sp randomized scheme replicates F1 F (F 0 phosphorus 50 100 biofertilizer, biofertilizer , ECw 03 3 0. 40 4. m1. m1 m 1 . m-1) (100 (5 index CO diameter photosynthesis rate conductance plants 10 m-1 (10 ( m- (1

RESUMO O amendoim (Arachis hypogaea) é uma importante cultura agrícola no Brasil, considerada uma das mais importantes oleaginosas cultivadas. O uso de bactérias solubilizadoras de fertilizantes pode mitigar o estresse salino. O objetivo deste estudo foi avaliar as trocas gasosas, o crescimento e a eficiência do uso da água da cultura do amendoim irrigado com água salobra sob adubação fosfatada e inoculada com bactérias do gênero Bacillus sp. O delineamento experimental utilizado neste estudo foi inteiramente casualizado, em esquema fatorial 4 × 2 × 2, com 5 repetições, referente às formas de adubação (F1 - 0% fósforo, F2 - 50% fósforo, F3 - 100% fósforo e F4 - bovino biofertilizante), presença e ausência do inoculante e dois níveis de condutividade elétrica da água de irrigação (CEa - 0.3 e 4.0 dS m-1). As adubações com fertilizante orgânico (100% de biofertilizante) e mineral (50 e 100% de fósforo) associada a Bacillus sp. mitigou os danos causados pelo estresse salino e proporcionou maior eficiência no uso da água, índice de clorofila, concentração interna de CO2 e diâmetro do caule. O tratamento controle (sem adubação fosfatada e sem estresse salino) e a aplicação de Bacillus sp., promoveu maior desempenho na fotossíntese líquida, taxa de transpiração, condutância estomática e altura das plantas em plantas de amendoim. Arachis hypogaea Brasil cultivadas gasosas sp casualizado repetições F1 F (F 0 50 100 biofertilizante, biofertilizante , CEa 03 3 0. 40 4. m1. m1 m 1 . m-1) (100 (5 clorofila CO caule líquida transpiração 10 m-1 (10 ( m- (1

Resumen Se desarrolló una metodología heurística, con el propósito de seleccionar un tratamiento pasivo caracterizado por poseer procesos químicos y/o biológicos para tratar los drenajes ácidos de mina, el cual no utiliza equipos externos y pueden cumplir su funcionamiento hasta por 20 años, lo anterior como alternativa para la remediación de un drenaje ácido de mina en la región de Soto Norte, Santander y que, de acuerdo con estudios realizados, presentó niveles de concentración de elementos, compuestos, tales como hierro, plomo, cobre, aluminio y sulfatos elevados, y pH ácido. Con el objetivo de encontrar alternativas exitosas y replicables de otras partes del mundo que presentan problemáticas similares, se realizó una búsqueda bibliográfica, que dio como resultado, 40 plantas industriales ubicadas en los siguientes países: Estados Unidos, Reino Unido, España, Nueva Zelanda y Canadá. Posteriormente, se evaluó cada una de ellas y se definieron las siguientes variables para su selección: la dilución de elementos contaminantes, flujo y el tiempo de funcionamiento, luego se procedió a graficarlas, categorizarlas y priorizarlas según su probabilidad de éxito. En este proceso, se obtuvo como resultado 3 plantas con una categorización de muy alta y 8 plantas con alta probabilidad de éxito, de las cuales, la planta denominada Cadillac Molybdenite de Canadá presentó el mejor desempeño teniendo en cuenta, el costo, número de etapas entre otros indicadores evaluados y la posibilidad que estas tecnologías puedan ser replicadas en Santander.

Abstract Aheuristic methodology was developed, with the purpose of selecting a passive treatment characterized by having chemical and/or biological processes to treat acid mine drainage, which does not use external equipment and can operate for up to 20 years, the above as an alternative to remediation of acid mine drainage in the province of Soto Norte, Santander and that, according to studies carried out, showed high concentration levels of elements, compounds such as iron, lead, copper, aluminum and sulphates, and acid pH. In order to find successful and replicable alternatives from other parts of the world that present similar problems, a bibliographic search was carried out, which resulted in 40 industrial plants located in the following countries: United States, United Kingdom, Spain, New Zealand and Canada. Subsequently, each of them was evaluated and the following variables were defined for their selection: dilution of pollutants, flow and time of operation, then they were graphed, categorized and prioritized according to their probability of success. In this process, we obtained as a result 3 plants with a very high categorization and 8 plants with high probability of success, of which, the plant called Cadillac Molybdenite of Canada presented the best performance taking into account, the cost, number of stages among other indicators evaluated and the possibility that these technologies can be replicated in Santander.

ABSTRACT Under controlled conditions, it has been shown that the application of humic substances (HS) favors the growth and development of plants. But, scientific evidence in open field conditions with and without irrigation has been poorly documented. The objective was to characterize the humic acids (HA) extracted from vermicompost of urban solid waste using chemical and spectroscopic techniques, and to evaluate the effect of its root application on the reproductive stage, with continuous irrigation and with induced water deficit, in three selections of maize (Zea mays L.) from three regions of the state of Oaxaca, Mexico, grown under field conditions. The regional corn selections used were identified as Cajete (Caj), Zapalote (Zap) and Cuilapam (Cuil). Three concentrations of HA were tested: 140, 150 and 160 mg L-1, a control treatment was included, without application. The product was applied by radical spraying, before, during and after the flowering stage of the corn plants. The HA promoted higher values in plant height, stem diameter, and production of root and shoot biomass, in the presence of irrigation and with induced water deficit. The relative content of water and proline were also stimulated, as well as the content of chlorophylls a, b, and a+b. The negative effects caused by an induced water stress were attenuated by the application of HA. HA from municipal solid waste vermicompost stimulated growth parameters in the reproductive phase and induced stress protection when irrigation use was limited.

RESUMEN En condiciones controladas, la aplicación de sustancias húmicas (SH) favorece el crecimiento y el desarrollo de las plantas. Pero la evidencia científica en condiciones de campo abierto con y sin riego, está escasamente documentada. El objetivo fue caracterizar los ácidos húmicos (AH) extraídos de vermicompost de residuos sólidos urbanos empleando técnicas químicas y espectroscópicas, y evaluar el efecto de su aplicación vía radical en la etapa reproductiva, con riego y déficit hídrico inducido, en tres selecciones de maíz (Zea mays L.) de tres regiones del estado de Oaxaca, México. Las selecciones regionales de maíz empleadas se identificaron como Cajete (Caj), Zapalote (Zap) y Cuilapam (Cuil). Se ensayaron tres concentraciones de AH: 140, 150 y 160 mg L-1, se incluyó un tratamiento control, sin aplicación. El producto se aplicó por aspersión vía radical, antes, durante y después de la etapa de floración de las plantas de maíz. Los AH promovieron mayor altura de la planta, diámetro del tallo, producción de biomasa radical y aérea, en presencia de riego y con déficit hídrico inducido. El contenido relativo de agua y de prolina también fue estimulado, así como el contenido de clorofilas a, b y a+b. Los efectos negativos causados por un estrés hídrico inducido fueron atenuados por la aplicación de los AH. Los AH procedentes de vermicompost de residuos sólidos urbanos estimularon los parámetros de crecimiento en la fase reproductiva e indujeron protección anti estrés cuando se limitó el uso del riego.

BACKGROUND: Plants are increasingly explored for their potential as antimicrobial agents. Spondias mombin plants have been used in folkloric medicine in the treatment of dental health and general health issues. AIMS AND OBJECTIVES: To compare zone of inhibition, minimum inhibitory concentration and minimum bactericidal concentration of S. mombin aqueous and ethanol stem bark, leaves and charcoal extracts on Streptococcus mutans. MATERIAL AND METHODS: Twenty grams of each plant part was soaked in 100ml of ethanol and boiled in distilled water and left to stand for 24h with intermittent shaking until evaporated. The dried filtrates were diluted to obtain concentrations of 500mg/ml, 250mg/ ml, 125mg/ml and 62.5mg/ml in duplicates. The zone of inhibition, minimum inhibition concentration and minimum bactericidal concentration tests on S mutans were carried out using a standard procedure. RESULTS: Ethanol and aqueous extracts of S. mombin displayed antimicrobial activity against Streptococcus mutans. The leaves and stem bark extracts demonstrated superior potency compared to charcoal extracts. Ethanol extracts (32.4mm) consistently exhibited stronger inhibitory effects than aqueous extracts (25mm). CONCLUSION: The salient feature of this study justifies the folkloric medicinal use of Spondias mombin plants in the treatment of toothaches and prevention of dental caries.