Summary: The castor plant (Ricinus communis L.) is a plant that has dif ferent benefits, such as the production of biodiesel and soil bioremediation. Due to the above, the castor plant’s ability to extract arsenic (As) was evaluated. For this, a randomized block experimental design with four repetitions was carried out. The evaluated treatments consisted of two types of biosolids (oxidation lagoon biosolids (BLO) and activated sludge biosolids (BLA) and four doses of As (0, 25, 50, 100 mg kg-1), under greenhouse conditions. As concentration was determined by inductively coupled plasma mass spectrometry (ICP-MS). From the quantification of As, the translocation factor (TF) and the bioaccumulation factor (FB) were estimated. The total nitrogen (N) content was quantified by the combustion method. Phosphorus (P) was analyzed by colorimetry using the metavanadate method, and the content of potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), manganese (Mn), iron (Fe) and zinc (Zn) was quantified by atomic absorption. For percentage of oil The Soxhlet method was used in the seed. The plant height and the dry weight of biomass did not vary due to the treatment ef fect (P ≤ 0.05). The Translocation Factor (TF) and the Bioconcentration Factor (BCF) registered ranges of 0.20 - 0.63 and 0.28 - 0.75, respectively. The applied doses of As did not af fect the biomass and nutrient absorption in the castor plant, which indicates that this plant species is tolerant to toxicity with productive potential in soils contaminated with this element, in concentrations up to 100 mg kg-1.

Resumen: La higuerilla (Ricinus communis L.) es una planta que tiene diferentes beneficios, como la producción de biodiesel y la biorremediación de suelo. Debido a lo anterior, se evaluó la capacidad de la higuerilla para extraer arsénico (As). Para ello, se realizó un diseño experimental de bloques al azar con cuatro repeticiones. Los tratamientos evaluados consistieron en dos tipos de biosólidos (biosólidos de lagunas de oxidación (BLO) y biosólidos de lodos activados (BLA) y cuatro dosis de As (0, 25, 50, 100 mg kg-1), bajo condiciones de invernadero. La concentración de As se determinó por espectrometría de masas por plasma acoplado inductivamente (ICP-MS). A partir de la cuantificación de As se estimó el factor de translocación (FT) y el factor de bioacumulación (FB). El contenido de nitrógeno (N) total se cuantifico por el método de combustión. El fósforo (P) se analizó por colorimetría por el método de metavanadato, y el contenido de potasio (K), calcio (Ca), magnesio (Mg), cobre (Cu), manganeso (Mn), hierro (Fe) y zinc (Zn) que se cuantificaron por absorción atómica. Para porcentaje de aceite en la semilla se utilizó el método Soxhlet. La altura de planta y el peso seco de biomasa no variaron por efecto de tratamiento (P ≤ 0.05). El Factor de translocación (FT) y el Factor de bioconcentración (FBC) registraron rangos de 0.20 - 0.63 y 0.28 - 0.75, respectivamente. Las dosis aplicadas de As no afectaron la biomasa y absorción de nutrientes en la planta de higuerilla, lo cual indica que esta especie vegetal es tolerante a la toxicidad con potencial productivo en suelos contaminados con este elemento, en concentraciones hasta de 100 mg kg-1.

Abstract Conjugated linoleic acid is considered a functional food since its consumption improves people’s health. This compound is found in the milk of ruminant animals and is synthesized in the rumen and mammary gland using linoleic and α-linolenic acids as substrates, which are widely found in forage plants. Nevertheless, there is little information regarding the content of fatty acids in forages, particularly of native species. Therefore, the study aimed to evaluate the chemical composition and fatty acid profile of native forage shrubs that are consumed by goats under extensive grazing in northern Mexico in 2019. For this, forage shrubs consumed by goats were collected. The selected forages were determined: dry matter, organic matter, crude protein, neutral detergent fiber, acid detergent fiber, total lipids, and fatty acid profile. The forage shrubs consumed by the goats in the rangeland were huizache [Vachellia farnesiana (L.) Wild.], mesquite [Prosopis laevigata (Humb & Bonpl) Wild], gobernadora [Larrea tridentata (Moç. & Seseé DC)] and chaparro prieto [Vachellia constricta (Bentham Siegler & Ebinger Waif)]. Of these, mesquite (CP 148 g kg-1 DM) and chaparro prieto (CP 147 g kg-1 DM) had the best crude protein contents; likewise, mesquite had a high concentration in linoleic (14.21 g 100 g-1 total fatty acids) and α-linolenic (36.22 g 100 g-1 total fatty acids) fatty acids, so these forage shrubs can be considered in the diet of goats that aim to increase the concentration of conjugated linoleic acid in milk or meat of grazing goats.

Resumen El ácido linoleico conjugado es considerado un alimento funcional ya que su consumo mejora la salud de las personas. Este compuesto se encuentra en leche de animales rumiantes y es sintetizado en el rumen y glándula mamaria utilizando como sustratos a los ácidos linoleico y α-linolenico, los cuales se encuentran en forma amplia en plantas forrajeras. Sin embargo, existe poca información respecto al contenido de ácidos grasos en forrajes, en particular, de especies nativas. Por lo tanto, el objetivo del estudio fue evaluar la composición química y perfil de ácidos grasos de arbustos forrajeros nativos que son consumidos por cabras bajo pastoreo extensivo en el norte de México, en 2019. Para ello, se realizó una colecta de arbustos forrajeros consumidos por cabras. A los forrajes seleccionados se le determino: materia seca, materia orgánica, proteína cruda, fibra detergente neutro, fibra detergente ácido, lípidos totales y perfil de ácidos grasos. Los arbustos forrajeros consumidos por las cabras en el agostadero fueron: huizache (Vachellia farnesiana (L.) Wild.), mezquite (Prosopis laevigata (Humb & Bonpl) Wild), gobernadora (Larrea tridentata (Moç. & Seseé DC) y chaparro prieto (Vachellia constricta (Bentham Siegler & Ebinger Waif). De estos, mezquite (PC 148 g kg-1 de MS) y chaparro prieto (PC 147 g kg-1 de MS) tuvieron los mejores contenidos de proteína cruda, asimismo, mezquite tuvo una alta concentración en los ácidos grasos linoleico (14.21 g 100 g-1 ácidos grasos totales) y α-linolenico (36.22 g 100 g-1 ácidos grasos totales), por lo que estos arbustos forrajeros pueden ser considerados en dieta de las cabras que tengan el objetivo de incrementar la concentración de ácido linoleico conjugado en leche o carne de cabras en pastoreo.

RESUMO O silício (Si) exerce múltiplos benefícios às culturas. A maioria dos estudos sobre Si foi realizada aplicando algum tipo de estresse. Sugeriu-se que a resposta positiva do Si é determinada pelo grau de estresse na planta. Há pouca informação sobre o efeito do silício na planta na ausência de fator de estresse induzido. O objetivo do estudo foi determinar o efeito do Si edáfico no crescimento, produção e concentração de antioxidantes em tomateiro em casa de vegetação sem estresse induzido. Os tratamentos foram três doses de Si (0,06, 0,12 e 0,18 g/planta) e uma testemunha (0,0 g/planta). Os tratamentos foram distribuídos em delineamento inteiramente casualizado com quatro repetições. A adição de Si nas plantas de tomate aumentou a produção de biomassa, o número de frutos e a produtividade. Além disso, nos tratamentos com maior dose de Si, a concentração de antioxidantes aumentou, assim como a capacidade antioxidante total. Sugere-se incluir Si nos programas de fertilização do tomate como uma alternativa sustentável para melhorar o crescimento e a produtividade das culturas. (Si culturas Sugeriuse Sugeriu se induzido 0,06, 006 0 06 (0,06 012 12 0,1 018 18 g/planta gplanta g 0,0 00 (0, g/planta. . repetições biomassa disso total Sugerese Sugere 0,06 01 1 0, (0 (

ABSTRACT Silicon (Si) has multiple benefits in crops. Most of the studies on Si have been carried out by applying some type of stress. It has even been suggested that the positive response of Si is determined by the degree of stress in the plant, and there is little information on Si and its effect on the plant when there is no induced stress factor. The objective of the study was to determine the effect of edaphic Si on the growth, production and concentration of antioxidants in tomato under greenhouse conditions without induced stress. The treatments were three doses of Si (0.06, 0.12 and 0.18 g/plant) and a control (0.0 g/plant). The treatments were distributed in a completely randomized design with four repetitions. The addition of Si in tomato plants increased biomass production, the number of fruits and yield. In addition, in the treatments with the highest dose of Si, the concentration of antioxidants increased, as well as the total antioxidant capacity. It is suggested to include Si in tomato fertilization programs as a sustainable alternative to improve crop growth and productivity. (Si crops factor 0.06, 006 0 06 (0.06 012 12 0.1 018 18 g/plant gplant g 0.0 00 (0. g/plant. . repetitions yield capacity productivity 0.06 01 1 0. (0 (

Abstract A criterion to estimate the application dose of biosolids in agricultural soils is the available nitrogen and the requirement of the crop. The objective of the study was to determine the nitrogen availability of two biosolids generated from different treatment systems and its effect on the oil yield from Ricinus communis L. seed. The treatments consisted of three sources of nitrogen (N) and three doses, in addition to a control without N. The sources of N were: ammonium sulfate (SA), biosolids from oxidation lagoons (BLO) and biosolids from activated sludge (BLA). The SA was considered as a commercial witness. The doses of N were 0, 3.79, 5.65 and 7.52 g pot-1, which correspond to 67%, 100% and 133% of the N requirement of the crop (RNC), respectively. The greenhouse experiment was established under a randomized block experimental design with four replications, where the experimental unit was one plant per pot. Nitrogen availability was estimated using the fertilizer equivalency method (EF). The dry matter (DM) was statistically similar between the treatments, being different from the control (p< 0.05). The DM and N extraction showed a quadratic response as a function of the applied N doses. The availability of N was 40.4 and 34.8% for the BLA and BLO, respectively.

Resumen Un criterio para estimar la dosis de aplicación de biosólidos en suelos agrícolas es el nitrógeno disponible y el requerimiento del cultivo. El objetivo del estudio fue determinar la disponibilidad de nitrógeno de dos biosólidos generados a partir de sistemas de tratamiento diferente y su efecto sobre el rendimiento de aceite a partir de semilla de Ricinus communis L. Los tratamientos consistieron en tres fuentes de nitrógeno (N) y tres dosis, además de un testigo sin N. Las fuentes de N fueron: sulfato de amonio (SA), biosólidos de lagunas de oxidación (BLO) y biosólidos de lodos activados (BLA). El SA se consideró como un testigo comercial. Las dosis de N fueron de 0, 3.79, 5.65 y 7.52 g maceta-1, que corresponden a 67%, 100% y 133% del requerimiento de N del cultivo (RNC), respectivamente. Se estableció el experimento en invernadero bajo un diseño experimental de bloques al azar con cuatro repeticiones, donde la unidad experimental fue una planta por maceta. La disponibilidad de nitrógeno se estimó mediante el método de equivalencia de fertilizante (EF). La materia seca (MS) fue estadísticamente similar entre los tratamientos, siendo diferentes del testigo (p< 0.05). La MS y la extracción de N mostraron una respuesta cuadrática en función a las dosis de N aplicado. La disponibilidad de N fue de 40.4 y 34.8% para los BLA y BLO, respectivamente.