Abstract Introduction: Various anthropic pressures affect the aquatic ecosystems of the foothills of Colombia. The response to environmental stressors is still unknown in bioindicator organisms such as Leptohyphidae. Objective: To determine the diversity of Leptohyphidae nymphs of the Quenane-Quenanito river, in two contrasting hydrological periods and its relationship with some physicochemical variables. Methods: In December (2014) and February (2015), organisms were collected with a Surber net at six stations along the current. Alpha and beta diversity was analyzed and redundancy analysis and generalized linear model were applied to establish the relationship between taxa and environmental variables. Results: Were identified 369 organisms belonging to four genera (Amanahyphes, Traverhyphes, Tricorythopsis, and Tricorythodes), two species, and eight morphospecies. Amanahyphes saguassu is reported for the first time for the Meta department. High diversity of Leptohyphidae nymphs was recorded in the transition to drought season and greater abundance in drought. Beta diversity indicated that the configuration of the assemblage changes spatially and temporally. Conclusions: Leptohyphidae organisms prefer fast habitats, particularly in the dry period where they find food (leaf litter, detritus) and shelter to establish themselves successfully; anthropic activities such as urbanization notably affect diversity. The high diversity recorded in this small river in the foothills of the plains reflects the need to increase this type of works and collection efforts of study material in the region.

Resumen Introducción: Varias presiones antrópicas sufren los ecosistemas acuáticos del piedemonte llanero en Colombia. La respuesta a estresores ambientales aún se desconoce en organismos bioindicadores como Leptohyphidae. Objetivo: Determinar la diversidad de ninfas de Leptohyphidae del río Quenane-Quenanito, en dos periodos hidrológicos contrastantes y su relación con algunas variables fisicoquímicas. Métodos: En diciembre (2014) y febrero (2015) se recolectaron organismos con red Surber en seis estaciones a lo largo del río. Se analizó la diversidad alfa y beta y se aplicó análisis de redundancia y modelos lineales generalizados con el fin de establecer la relación entre los taxones y las variables ambientales. Resultados: Se identificaron 369 organismos pertenecientes a cuatro géneros (Amanahyphes, Traverhyphes, Tricorythopsis y Tricorythodes), dos especies y ocho morfoespecies. Se reporta por primera vez para el departamento del Meta Amanahyphes saguassu. Se registró la mayor diversidad de ninfas en la transición a la sequía y la mayor abundancia en sequía. La diversidad beta señaló que la configuración del ensamblaje cambia a nivel espacial y temporal. Conclusiones: Los organismos de Leptohyphidae prefieren hábitats de corrientes, particularmente en el periodo de sequía, donde hallan alimento (hojarasca, detritos) y refugio para establecerse exitosamente; actividades antrópicas como la urbanización afectan notablemente la diversidad. La alta diversidad registrada en este pequeño río de piedemonte llanero refleja la necesidad de incrementar este tipo de trabajos y esfuerzos de recolección de material de estudio en la región.

Abstract Introduction. There is a great human concern about antibiotics resistance due to their inappropriate use as growth promoters in animal husbandry. Objective. To evaluate the effect of a high level of zinc as a substitute to antibiotics in nursery pigs. Material and methods. The study was carried out from June to August 2022 in the province of Chiriqui, Panama. The experimental period was composed of three phases with 14 days per phase. The nursery pigs (n= 54) were distributed to one of three treatments with six replicates per treatment and three pigs per replicate. The treatments were: 1) control diet, which was formulated to meet the nutritional requirements for nursery pigs; 2) similar to treatment 1, plus 200 mg of amoxicillin/kg of feed and 40 mg of florfenicol/kg of feed during phase 1 (P1) and phase 2 (P2), respectively; and 3) similar to treatment 1, plus 2000 ppm and 1600 ppm of zinc during P1 and P2, respectively. In phase 3 (P3), all pigs were fed a common diet. Results. The supplementation of zinc improved the average daily gain in all phases. Pigs fed zinc diet had better F:G ratio in P2 compared to pigs fed antibiotic diet (p < 0.05). A higher concentration of hemoglobin and percentage of monocytes was found in pigs fed with higher level of zinc than the other treatments (p < 0.05). Furthermore, Pigs fed the antibiotic, or the control diet had a lower percentage of fecal dry matter compared to those supplemented with zinc. (p < 0.05). Conclusion. The supplementation of high levels of zinc exerted improvements, in comparison to the antibiotic, in terms of hemoglobin concentration, incidence of diarrhea and weight gain in pigs during 42 days after weaning.

Resumen Introducción. Existe una gran preocupación humana por la resistencia a los antibióticos debido a su uso inadecuado como promotores del crecimiento en la cría de animales. Objetivo. Evaluar el efecto de altos niveles de zinc como sustituto del antibiótico en lechones destetados. Material y métodos. El estudio se realizó de junio a agosto de 2022 en la provincia de Chiriquí, Panamá. El periodo experimental estuvo compuesto por tres fases con 14 días por fase. Los cerdos destetados (n= 54) fueron asignados a uno de tres tratamientos con seis repeticiones por tratamiento y tres cerdos por repetición. Los tratamientos fueron: 1) dieta control, formulada para suplir los requerimientos nutricionales para cerdos destetados; 2) similar al tratamiento 1, más 200 mg de amoxicilina/kg de alimento y 40 mg de florfenicol/kg de alimento durante la fase 1 (P1) y fase 2 (P2), respectivamente; y 3) similar al tratamiento 1, más 2000 ppm y 1600 ppm de zinc durante P1 y P2, respectivamente. En la fase 3 (P3), todos los cerdos fueron alimentados con una dieta común. Resultados. La suplementación con zinc mejoró la ganancia de peso en todas las fases. Los cerdos alimentados con zinc tuvieron mejor relación F:G en P2 en comparación a los cerdos suplementados con antibiótico (p < 0.05). Se encontró una mayor concentración de hemoglobina y porcentaje de monocitos en cerdos alimentados con zinc que en los otros tratamientos (p < 0.05). Los cerdos alimentados con antibiótico o la dieta control tuvieron un menor porcentaje de materia seca fecal en comparación a los suplementados con zinc (p < 0.05). Conclusión. La suplementación de altos niveles de zinc ejerció mejoras, en comparación al antibiótico, en cuanto a la concentración de hemoglobina, incidencia de diarrea y ganancia de peso en cerdos durante los 42 días posteriores al destete.

The Cuban industry La Purísima produces sauces and dressings for the national gastronomy; but it does not have a process for the deposition of chicken eggshells, as a result, 220 kg of eggshells are dumped daily, which generate a negative impact on the environment. The research evaluates the drying of hen eggshells with protein membrane on a laboratory scale, with a view to revalorizing this waste in the production of a calcium-rich poultry feed supplement. The calcium carbonate content of the shell was determined to confirm the potential application of the residue. The drying curve and drying rate curve was obtained by experimental measurement in a drying oven under aeration at 90 °C. The calcium carbonate content of the residue was 93,33 %. The drying curve was fitted to an exponential mathematical model as a function of the drying constant and the moisture in equilibrium at a temperature of 90 °C. The drying regime of the solid presented a period of decreasing drying rate up to a moisture value of 0,021 kg of water / kg of dry solid, for lower values, this presented a deviation from the exponential function in its rate. The utilization of residual eggshells proved to be an attractive source of calcium carbonate with potential for its use in the production of feed supplement for poultry.

RESUMEN En la Industria cubana La Purísima se producen salsas y aderezos para la gastronomía nacional; pero no dispone de un proceso para la deposición de las cáscaras de huevo de gallina, como resultado, se vierten diariamente 220 kg de cáscaras que generan un impacto negativo en el medio ambiente. La investigación evalúa el secado de las cáscaras de huevo de gallina con membrana proteica a escala de laboratorio, con vistas a revalorizar este residuo en la producción de un suplemento alimenticio para aves de corral rico en calcio. Se determinó el contenido de carbonato de calcio en la cáscara para confirmar la aplicación potencial del residuo. La curva de secado y del régimen de secado se obtuvo por medición experimental en un secadero bajo aireación a 90 °C. El contenido de carbonato de calcio en el residual fue de 93,33 %. La curva de secado se ajustó a un modelo matemático exponencial en función de la constante de secado y la humedad en equilibrio a una temperatura de 90 °C. El régimen de secado del sólido presentó un período de velocidad de secado decreciente hasta un valor de humedad de 0,021 kg de agua / kg de sólido seco, para valores inferiores presentó una desviación de la función exponencial en su velocidad. El aprovechamiento de las cáscaras de huevo residuales resultó ser una fuente atractiva de carbonato de calcio con potencialidades para su utilización en la elaboración de suplemento alimenticio para aves de corral.

ABSTRACT Globally, there is enough evidence to affirm that climate change is one of the main factors causing the changing trends in rainfall features (CTRFs). The aim of this study, therefore, is to assess the CTRFs across the rice cultivation regions (RCRs) of the Plain of Reeds in Vietnam. Vietnam is a prime example of the impacts of climate change (ICC) on agricultural activities. Daily rainfall data series from 16 observation stations during the period 1984-2015 were appraised for quality and then the CTRFs were detected by applying the Mann_Kendall test and Sen’s slope estimator. The quality of rainfall data at all observation stations is homogeneous with a significance level of 0.05. Over a year, the trends in rainfall features slightly increased at most obsrvation stations, except for Hong Ngu and Moc Hoa. Additionally, the trends in rainfall features slightly decreased in rainny season rainfall (RSR) at 10 out of 16 observation stations, while insignificant to significant increasesing in dry season rainfall (DSR) were detected at all observation stations. Globally CTRFs. . (CTRFs) study therefore RCRs (RCRs ICC (ICC activities 1 19842015 1984 2015 1984-201 MannKendall Mann Kendall Sens Sen s estimator 005 0 05 0.05 year Hoa Additionally RSR (RSR DSR (DSR (CTRFs 1984201 198 201 1984-20 00 0.0 198420 19 20 1984-2 0. 19842 2 1984-

RESUMO Globalmente, há evidências suficientes para afirmar que a mudança climática é um dos principais fatores que causam as tendências de mudança nas características das chuvas (TMCCs). O objetivo do estudo, portanto, é avaliar as TMCCs nas regiões de cultivo de arroz (RCAs) da Planície de Reeds. Vietnã é um excelente exemplo dos impactos das mudanças climáticas (IMC) nas atividades agrícolas. Para realização deste estudo, as séries diárias de dados de precipitação em 16 estações de observação durante o período de 1984-2015 foram avaliadas quanto à qualidade e, em seguida, foram detectadas as TMCCs aplicando o teste de Mann-Kendall e o estimador de inclinação de Sen. A qualidade dos dados pluviométricos em todas as estações de observação é homogênea com nível de significância de 0,05. Na escala anual, houve uma tendência crescente insignificante na maioria das estações de observação, exceto Hong Ngu e Moc Hoa, e uma tendência insignificante decrescente na precipitação da estação chuvosa foi detectada em 10 das 16 estações de observação, enquanto tendências crescentes insignificantes a significativas foram detectadas em todas estações de observação. Pode-se confirmar que a área de estudo está passando por um estágio crescente da precipitação na estação seca (PES). Os achados do estudo contribuem positivamente para as atividades agropecuárias, ampliando o entendimento do IMC sobre as características pluviométricas. Globalmente TMCCs. . (TMCCs) portanto RCAs (RCAs Reeds (IMC agrícolas 1 19842015 1984 2015 1984-201 seguida MannKendall Mann Kendall Sen 005 0 05 0,05 anual Hoa Podese Pode se PES. PES (PES) agropecuárias pluviométricas (TMCCs 1984201 198 201 1984-20 00 0,0 (PES 198420 19 20 1984-2 0, 19842 2 1984-

Resumen La industria pesquera genera subproductos que al acumularse causan problemas de contaminación ambiental; sin embargo, podrían ser una fuente de nutrientes para rumiantes. El objetivo de este estudio fue evaluar la respuesta sobre el microbioma ruminal, la digestibilidad aparente y productividad de borregos Katahdin alimentados con diferentes niveles de harina de caparazón de camarón (HCC). Cuatro borregos machos con peso vivo de 22 ± 2.5 kg fueron asignados en un diseño cuadrado latino (4 animales x 4 tratamientos) repetido. Los animales fueron asignados durante 16 días por periodo a dietas con 0, 5, 10 y 20 g 100 g-1 de MS de HCC, los tratamientos fueron: HCC0, HCC5, HCC10 y HCC20, respectivamente. La mayor ganancia diaria de peso se tuvo en los animales del tratamiento HCC5 (P ≤ 0.05). Sin embargo, el mayor consumo de materia seca se observó en los animales con la dieta HCC20 (P ≤ 0.05). En la digestibilidad aparente de la materia seca no hubo diferencia entre tratamientos (P > 0.05), ni en la concentración de bacterias totales (P > 0.05), mientras que la concentración de bacterias celulolíticas y de bacterias degradadoras de quitina, fue mayor en los animales del tratamiento con HCC20 (P ≤ 0.05). Los resultados indican una adaptación del microbioma ruminal a dosis altas de HCC, por tanto, se puede usar HCC en dietas para borregos sin efecto en el metabolismo y microbiana ruminal, la digestibilidad de los nutrientes y en el desempeño de los animales.

Abstract The fishing industry produces byproducts that accumulate and cause environmental pollution problems; however, could be used as an alternative source of nutrients in ruminants. The objective of the present study was to evaluate the response over ruminal microbiome, apparent digestibility and productivity of Katahdin lambs fed different levels of shrimp shell meal (HCC). Four male lambs with live weight of 22 ± 2.5 kg were assigned in a repeated Latin square design (4 animals x 4 treatments). The animals were assigned for 16 days per period to diets with 0, 5, 10 and 20 g 100 g DM of HCC, the treatments were: HCC0, HCC5, HCC10 and HCC20, respectively. The greatest daily weight gain was found in the HCC5 treatment (P ≤ 0.05). However, the highest dry matter intake was observed in animals with the HCC20 diet (P ≤ 0.05). In the apparent digestibility of the dry matter there was no difference between treatments (P > 0.05), neither in the concentration of total bacteria (P > 0.05), while the concentration of cellulolytic bacteria and chitin-degrading bacteria was higher in the animals from HCC20 treatment (P ≤ 0.05). The results indicate an adaptation of the ruminal microbiome to high doses of HCC, therefore, HCC can be used in diets for sheep without effect on rumen metabolism and microbial, nutrient digestibility and animal performance.

ABSTRACT: Cowpea is a food crop representing an important source of proteins and income, mainly for people living in the north and northeast of Brazil. This study aimed to evaluate the growth performance of two cowpea cultivars under four different ionic concentrations of the growth solution. Thus, a pot experiment was performed using the sand culture technique and set up in a completely randomized design with a 2 x 4 factorial scheme, using four replications and one plant per plot. After the period of growth, the parameters such as length of the shoot, stem diameter, number of leaves, number of secondary branches, number of pods, fresh weight of the stem, stem dry mass, leaf dry mass, shoot dry mass, and root/shoot ratio were obtained. The results pointed out that there was a significant interaction effect on parameters like stem diameter, leaf dry mass, shoot dry mass, and number of leaves. Both cultivars were strongly responsive to changes in ionic concentration, indicating a greater biomass production at ionic concentrations of 90% and 120%. A greater growth performance for BRS Rouxinol than BRS Itaim was observed, while the second cultivar indicated a high tolerance as exposed to the highest ionic concentrations. ABSTRACT income Brazil solution Thus scheme plot diameter leaves branches pods mass rootshoot root obtained concentration 90 120 120% observed 9 12 1

RESUMO: O feijão-caupi é um alimento que representa uma importante fonte de proteínas, e também de renda, sobretudo para os produtores rurais do Norte e Nordeste do Brasil. O objetivo deste estudo foi avaliar o desempenho de crescimento de duas cultivares de feijão caupi sob diferentes concentrações iônicas da solução nutritiva. Para tanto, um experimento em vasos foi conduzido em delineamento inteiramento casualizado com arranjo fatorial 2 x 4, utilizando quatro repetições e um planta por parcela. Após o período de crescimento, os parâmetros tais como: comprimento do ramo principal, diâmetro do caule, número de folhas, número de ramos secundários, número de vagens, peso fresco do caule, peso seco do caule, peso seco das folhas, peso seco da parte aérea e a relação raiz parte aérea foram obtidas. Os resultados apontaram que houve interação significativa dos fatores sobre o diâmetro do caule, peso seco das folhas, peso seco da parte aérea e o número de folhas. Ambas as cultivares foram responsivas a mudança na concentração iônica da soução, revelando maior rendimento de biomassa nas concentrações de 90% e 120%. Uma maior performance de crescimento foi constatada para BRS Rouxinol comparado a BRS Itaim, enquanto a segunda cultivar mostrou elevada tolerância às altas concentrações iônicas na solução. RESUMO feijãocaupi proteínas renda Brasil nutritiva tanto 4 parcela como principal caule folhas secundários vagens obtidas soução 90 120 120% Itaim 9 12 1

ABSTRACT The objective of this study was to evaluate the ecophysiological aspects and biomass production of three soybean genotypes subjected to soil flooding in the vegetative and/or reproductive stages. The design adopted was completely randomized with 5 replications, in a 3 x 3 factorial arrangement, with three soybean genotypes: PELBR 17-46, PELBR 15-7016, and 75I77RSF IPRO; and three water treatment conditions: soil flooding for 10 days in the vegetative period + 10 days in the reproductive period; soil flooding for 10 days only in the reproductive period, and the control treatment, where the soil was maintained at 70% of field capacity. There was a reduction in the relative water content for the PELBR 15-7016 and PELBR 17-46 genotypes in the vegetative/reproductive stages and in the reproductive stage, while for the 75I77RSF IPRO there was no difference. The levels of chlorophyll a, chlorophyll b, and total chlorophyll were reduced only for the PELBR 15-7016 and 75I77RSF IPRO genotypes. The dry matter in the leaves and roots was lower for PELBR 17-46 and PELBR 15-7016 when subjected to stress in the R2 soybean stage and for the grain production. PELBR 17-46 and PELBR 15-7016 genotypes are more susceptible to stress, while the 75I77RSF IPRO showed mechanisms to overcome waterlogging stress. andor or replications arrangement 1746, 1746 17 46, 46 157016, 157016 15 7016, 7016 IRSF I RSF conditions 1 70 capacity 15-701 17-4 vegetativereproductive difference b R 174 4 15701 701 7 15-70 17- 1570 15-7 157 15-

RESUMO O objetivo deste trabalho foi avaliar aspectos ecofisiológicos e produção de biomassa de genótipos de soja submetidos ao alagamento do solo nas fases vegetativa e/ou reprodutiva. O delineamento adotado foi o inteiramente casualizado com 5 repetições, em arranjo fatorial 3 x 3, com três genótipos de soja: PELBR 17-46, PELBR 15-7016 e 75I77RSF IPRO; e três condições de tratamento de água: alagamento do solo por 10 dias no período vegetativo + 10 dias no período reprodutivo; alagamento do solo por 10 dias apenas no período reprodutivo, e o tratamento testemunha, onde o solo foi mantido a 70% da capacidade de campo. Houve redução no teor relativo de água para os genótipos PELBR 15-7016 e PELBR 17-46 no vegetativo/reprodutivo e no reprodutivo, enquanto para 75I77RSF IPRO não houve diferença. Os teores de clorofila a, b e total foram reduzidos apenas para os genótipos PELBR 15-7016 e 75I77RSF IPRO. A matéria seca nas folhas e raízes foram menores para PELBR 17-46 e sensíveis quando submetidos ao estresse no estádio R2 da soja e para a produção de grãos. Os genótipos PELBR 17-46 e PELBR 15-7016 são mais suscetíveis ao estresse, enquanto o 75I77RSF IPRO apresentou mecanismos para superar o estresse por encharcamento. eou ou reprodutiva repetições 1746, 1746 17 46, 46 157016 15 7016 15-701 IRSF I RSF 1 reprodutivo testemunha 70 campo 17-4 vegetativoreprodutivo diferença R grãos encharcamento 174 4 15701 701 15-70 7 17- 1570 15-7 157 15-

Resumen Las dosis de paclobutrazol que reducen la altura del tallo floral o modifican el aspecto visual pueden ser distintas para cada cultivar. En esta investigación se evaluó el efecto de ocho concentraciones de paclobutrazol en la altura del tallo, aspecto visual, periodo de antesis y distribución de biomasa de Lilium asiático cv. Litouwen. Dieciocho bulbos fueron sumergidos por 24 h en 5 L de las siguientes soluciones: 0 (control), 2.5, 5, 10, 20, 40, 100, 200 mg L-1 de paclobutrazol. Transcurrido el tiempo, tres bulbos se plantaron en macetas con 2.5 L de tezontle y se distribuyeron al azar en el interior de un invernadero. Durante el ciclo del cultivo, de 2022, la humedad del sustrato se mantuvo con solución Steiner. Los resultados se procesaron con análisis de varianza y pruebas de comparación de medias (Tukey, p≤ 0.05). La altura de los tallos florales fue de 61.5, 56.6, 43.4, 29.1, 18.4 y 14.1 cm con 0 o 2.5, 5 o 10, 20, 40, 100 y 200 mg L-1 de paclobutrazol respectivamente. El número de hojas y el área foliar disminuyeron, pero el diámetro del tallo, índice de verdor, biomasa seca de raíces, botones florales, tiempo a la floración y periodo de antesis se incrementaron a partir de 40 mg L-1. En Lilium ‘Litouwen’ se requieren dosis de 40 o 100 mg L-1 de paclobutrazol para obtener plantas compactas con follaje verde intenso y botones florales llamativos, lo que ayudaría a su comercialización como plantas de maceta.

Abstract The doses of paclobutrazol that reduce the height of the flower stem or modify the visual appearance may be different for each cultivar. In this research, the effect of eight paclobutrazol concentrations on stem height, visual appearance, anthesis period, and biomass distribution of Asiatic Lilium cv. Litouwen was evaluated. Eighteen bulbs were immersed for 24 h in 5 L of the following solutions: 0 (control), 2.5, 5, 10, 20, 40, 100, 200 mg L-1 of paclobutrazol. After some time, three bulbs were planted in pots with 2.5 L of tezontle and randomly distributed inside a greenhouse. During the 2022 crop cycle, the moisture of the substrate was maintained with a Steiner solution. Results were processed with analysis of variance and Tukey’s mean comparison tests (p≤ 0.05). The height of the flower stems was 61.5, 56.6, 43.4, 29.1, 18.4, and 14.1 cm with 0 or 2.5, 5 or 10, 20, 40, 100, and 200 mg L-1 of paclobutrazol, respectively. Leaf number and leaf area decreased, but stem diameter, greenness index, dry root biomass, flower buds, time to flowering and anthesis period increased from 40 mg L-1. In Lilium ‘Litouwen’, doses of 40 or 100 mg L-1 of paclobutrazol are required to obtain compact plants with intense green foliage and striking flower buds, which would help their marketing as pot plants.

RESUMEN Pese a la liberalización de la agricultura durante las últimas décadas, México se encuentra cerca de la autosuficiencia en el caso del frijol. El comportamiento del mercado de este grano está determinado principalmente por factores internos que afectan tanto la demanda como la oferta. En este contexto, el objetivo del presente artículo es analizar el movimiento de los precios de frijol negro bola en Zacatecas y el frijol pinto en Chihuahua, y el movimiento de precios para las mismas variedades en la Ciudad de México; para ello, se emplearon precios mensuales del periodo agosto 2005 - junio 2022. El análisis se realizó con métodos econométricos que determinan la transmisión horizontal de precios. Los resultados indican la presencia de cointegración para los precios de frijol negro bola, así como una causalidad en ambas direcciones. También se encontró causalidad en ambas direcciones para el frijol pinto, aunque los precios no están cointegrados.

ABSTRACT Despite the liberalization of agriculture experienced during the recent decades, Mexico is close to self-sufficiency in the case of dry bean. The behavior of the market for this grain is determined mainly by internal factors influencing both demand and supply. In this context, the objective of this paper is to analyze the movement of prices for negro bola bean in Zacatecas and pinto bean in Chihuahua, and the movement of prices for the same varieties available in Mexico City; for this purpose, monthly prices for the period August 2005 - June 2022 were used. The analysis was carried out using econometric methods that determine the presence of horizontal price transmission. The results indicate the presence of cointegration for negro bola bean prices, and causality running in both directions. We also found causality running in both directions for pinto bean, although the prices are not cointegrated.

Abstract Destruction of the harvest of cotton stalks should be done after it. However, destruction by ploughing prevents continuing with direct sowing, which makes chemical management an ally in soil conservation. The objective was to identify the most effective dose of 2,4-D, associated with different herbicides and the timing of administration for the control of transgenic cotton shoots for tolerance to glyphosate and glufosinate. The treatments consisted of the use of the herbicide 2,4-D, alone at doses of 670 and 1 340 g ha-1, and associated with the herbicides carfentrazone, flumiclorac, chlorimuron, flumioxazin and imazethapyr at three application times: 0 days after mechanical mowing (0 DAMM), 25 DAMM, and 0 DAMM + 25 DAMM. Regrowth evaluations were performed at 15, 30, and 45 days after the first and second applications, determining the dry biomass of the shoots. In terms of herbicide use time, the best results are obtained when they applied at 0 DAMM + 25 DAMM. Higher doses of 2,4-D (1 324 g ha-1) make it more efficient; in relation to herbicides, variations were perceived in their behavior depending on the time of evaluation, the application, and the dose of 2,4-D used. During the last measurement period, 45 days after application, 2,4-D+carfentrazone and 2,4-D+flumiclorac had the lowest dry shoot masses. The experiment was conducted in 2014. It was concluded that there is a lower rate of cotton regrowth when the application of the herbicides is repeated at 0 DAMM and 25 DAMM. The 1 324 g ha-1 dose of 2,4-D is more efficient. 2,4-D+carfentrazone and 2,4-D+flumiclorac promoted lower dry mass 45 days after administration of the treatments.

Resumen La destrucción de la cosecha de tallos de algodón debe realizarse después de esta. Sin embargo, la destrucción por arado impide continuar con la siembra directa, lo que hace que el manejo químico sea un aliado en la conservación del suelo. El objetivo fue identificar la dosis de 2,4-D, asociada a diferentes herbicidas y el momento de administración más eficazes para el control de retoños de algodón transgénico para tolerancia a glyphosate y glufosinate. Los tratamientos consistieron en el uso aislado del herbicida 2,4-D, a dosis de 670 y 1 340 g ha-1, y asociado a los herbicidas carfentrazone, flumiclorac, chlorimuron, flumioxazin y imazethapyr en tres tiempos de aplicación: 0 días después de la siega mecánica (0 DARM), 25 DARM, y 0 DARM + 25 DARM. Se evaluó el rebrote a los 15, 30 y 45 días después de la primera y segunda aplicación. Las evaluaciones de rebrote se realizaron a los 15, 30 y 45 días después de la primera y segunda aplicación, determinando la biomasa seca de los brotes. En cuanto al tiempo de uso de los herbicidas, los mejores resultados se obtienen cuando se suministró 0 DARM +25 DARM. Dosis más altas de 2,4-D (1 324 g ha-1) lo hacen más eficiente relaciona a los herbicidas se percibieron variaciones en su comportamiento según el tiempo de evaluación, la aplicación y la dosis de 2,4 D utilizada. Durante el último período de medición, 45 días después de la aplicación, 2,4-D+carfentrazone y 2,4-D+flumiclorac presentaron las masas secas de yema más bajas. El experimento se llevó a cabo en 2014. Se concluyó que existe una menor tasa de rebrote del algodón cuando se repite la aplicación de los herbicidas 0 DARM y 25 DARM. La dosis de 1 324 g ha-1 de 2,4-D es más eficiente. 2,4-D+carfentrazona y 2,4-D+flumiclorac promovieron una menor masa seca 45 días después de la administración de los tratamientos.

ABSTRACT The concentration of linoleic and α-linolenic fatty acids (FA) in grasses can be increased through agronomic techniques; however, there is little information in this regard for tropical grasses. Therefore, the objective of the study was to evaluate the effect of N fertilization and regrowth age management on the FA profile of three tropical grasses. To do this, three plots of 100 m2 each were used for the species: Urochloa decumbens (Stapf) R.D. Webster, U. humidicola (Rendle) Morrone & Zuloaga, and Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs. The study was conducted during dry and rainy seasons. In each period, they were divided into two subplots and only one of them was fertilized. Grass sampling was carried out on days 20, 25, and 30 after fertilization. Five samples were taken from each subplot and an agronomic evaluation was made before each cut. The chemical composition and lipid profile were then determined. An ANOVA of a randomized complete block design with split plot arrangement was performed. The concentration of linoleic and α-linolenic acid was higher in M. maximus during drought (48.5 g 100 g-1 FA) and in U. humidicola during the rainy season (55.1 g 100 g-1 FA). This proportion was higher on day 20 (50.5 g 100 g-1 FA) compared to that recorded on days 25 and 30 (50.1 and 45.7 g 100 g-1 FA, respectively). The fertilized grasses had a higher concentration of linoleic and α-linolenic acid compared to the unfertilized ones (53.4 vs. 44.3 g 100 g-1 FA). It is concluded that fertilization with 50-20-00 (N-P-K) increases the proportion of linoleic and α-linolenic acids in grasses; however, such concentration decreases with increasing plant maturity.

ABSTRACT: In the peruvian highlands, the production of alfalfa and the fattening of guinea pigs face issues that impact the breeders' economy. A study in the hamlet of Coñaica (Panao, Pachitea, Huánuco) was conducted to assess the impact of biofertilization on alfalfa biomass and guinea pig fattening. Two experimental designs were implemented: the RCBD to measure alfalfa biomass and a CRD to study the fattening of weaned guinea pigs (both males and females). The three evaluated treatments included the application of Effective Microorganisms (EM) to the foliage (T1), EM to the soil (T2), and a control group without EM, with a dosage of 10% every 15 days. Biofertilized alfalfa was used as feed for male and female guinea pigs for a period of nine weeks. It was distinguished that the EM treatment to the foliage significantly increased the biomass of alfalfa and favorably affected the fattening of guinea pigs, although a significant improvement in the feed conversion rate was only observed in male guinea pigs. These findings suggest that foliar EM applications with a dosage of 10% every 15 days promote higher alfalfa productivity and enhance the guinea pig fattening process.

RESUMEN: En la sierra peruana, la producción de alfalfa y el engorde de cuyes enfrentan problemas que impactan la economía de los criadores. Un estudio en el Caserío de Coñaica (Panao, Pachitea, Huánuco) se llevó a cabo para evaluar el impacto de la biofertilización en la biomasa de alfalfa y el engorde de cuyes. Se implementaron dos diseños experimentales: DBCA para medir la biomasa de alfalfa y DCA para estudiar el engorde de cuyes destetados (machos y hembras). Los tres tratamientos evaluados fueron: aplicación de microorganismos eficaces (EM) al follaje (T1), EM al suelo (T2) y un grupo de control sin EM, con dosis del 10% cada 15 días. La alfalfa biofertilizada se utilizó como alimento para los cuyes machos y hembras durante nueve semanas. Se distinguió que el tratamiento de EM al follaje incrementó significativamente la biomasa de la alfalfa y afectó favorablemente al engorde de los cuyes, aunque solo se evidenció una mejora significativa en la conversión alimenticia de los cuyes machos. Estos resultados indican que las aplicaciones de EM al follaje con una dosis del 10% cada 15 días promueven una mayor productividad en la alfalfa y benefician el proceso de engorde de los cuyes.

We measured the tree transpiration of 9-year-old, Eucalyptus grandis x Eucalyptus urophylla clonal hybrid (GU) trees in the commercial forestry area of northern KwaZulu-Natal, South Africa. Transpiration was measured using the heat ratio method over two consecutive hydrological years (2019/20 and 2020/21) and up-scaled to a stand level. Leaf area index (LAI), quadratic mean diameter, and soil water content (SWC) were measured over the same period using an LAI 2200 plant canopy analyser, manual dendrometers and CS616 sensors, respectively. The depth to groundwater was estimated to be approx. 28 m, using a borehole next to our study site. Results showed that transpiration followed a seasonal pattern, with daily mean of 2.3 mm-tree-1-day-1 (range: 0.18 to 4.55 mm-tree-1-day-1) and 3.3 mm-tree-1-day-1 (range: 0.06 to 6.6 mm-tree-1-day-1) for 2019/20 and 2020/21, respectively. Annual GU transpiration was higher than that found by international studies under similar conditions, but was within the same transpiration range as Eucalyptus genotypes in the KwaMbonambi area. Plantation water productivity, calculated as a ratio of stand volume to transpiration, was higher than for other published studies, which was attributed to a very high productive potential of the study site. Multiple regression using the random forests predictive model indicated that solar radiation, SWC and air temperature highly influence transpiration. There is a high possibility that our GU tree rooting system extracted water in the unsaturated zone during the dry season. Due to the use of short-term results in this study, the impact of GU on water resources could not be quantified; however, previous long-term paired catchment studies in South Africa concluded that Eucalyptus has a negative impact on water resources. Further research is suggested with long-term measurements of transpiration and total evaporation and an isotope study to confirm the use of water by GU trees in the unsaturated zone.

Resumen La aplicación de herbicidas preemergentes es una estrategia de control de malezas, sin embargo, estos productos deben presentar residualidad para el control de diferentes flujos germinativos. Este estudio tuvo como objetivo evaluar la eficacia de herbicidas preemergentes en diferentes flujos de germinación de Merremia aegyptia, Mucuna aterrima y Ricinus communis, cuando se aplican sobre diferentes cantidades de paja y diferentes períodos secos simulados. El experimento se realizó en un diseño factorial 4 × 2 × 2 con cuatro repeticiones, el tratamiento incluye cuatro períodos secos (0, 30, 60 y 90), dos cantidades de paja (0 y 10 t ha-1) y dos flujos de germinación. Los herbicidas amicarbazona (1225 g ha-1); imazapic (147 g ha-1), sulfentrazona (800 g ha-1) y tebuthiuron (900 g ha-1), se aplicaron para el control de malezas antes de la emergencia, y los flujos de flujo de germinación se evaluaron a los 7, 14, 21, 28 y 35 días después de la emergencia de especies (DAE), mientras se verifica la masa seca. La amicarbazona presentó una reducción del control para todas las especies en los periodos secos más prolongados y presencia de paja. La amicarbazona mostró menos del 80% de control para todas las especies a los 90 días del período seco en presencia de paja. Imazapic no presentó residuo control para ninguna de las especies analizadas. Para sulfentrazona, la cantidad de paja no afectó el control de las malezas en diferentes flujos de germinación, mostrando el mismo patrón de control independientemente de la cantidad de paja, porcentajes de control superiores al 80% independientemente de la cantidad de paja. Los herbicidas asociados a cantidades de paja y periodos secos tienen impacto sobre las especies de malezas M.aegyptia, M.aterrima y R. communis.

Abstract Preemergent herbicides are a frequent weed control strategy. Considering different crop germinative fluxes, these products must present long-lasting weed control. This study evaluated preemergent herbicides in different germination fluxes of Merremia aegyptia, Mucuna aterrima and Ricinus communis when applied to different quantities of straw and different simulated dry periods. The experiment was conducted in a 4 × 2 × 2 factorial design with four replications. The treatments included four dry periods (0, 30, 60, and 90 days), two straw quantities (0 and 10 t ha-1), and two germination fluxes. The herbicides amicarbazone (1225 g ha-1), imazapic (147 g ha-1), sulfentrazone (800 g ha-1), and tebuthiuron (900 g ha-1) were applied for preemergence weed control, and germination flush fluxes were evaluated at 7, 14, 21, 28, and 35 days after emergence (DAE) while verifying plant dry mass. Amicarbazone controlled less than 80% of the studied species at the 90-day dry period in the presence of straw. Imazapic did not present control residue for any of the species analyzed. Sulfentrazone showed the same control pattern at all germination fluxes, regardless of the amount of straw. Tebuthiuron successfully controlled all species in the first germination flush, exceeding 80% regardless of the amount of straw. Herbicides associated with straw quantities and dry periods have a significant impact on M. aegyptiaca, M. aterrima and R. communis.

ABSTRACT Harvest delay can alter the physiological and sanitary quality of sorghum seeds due to the longer exposure time of seeds to adverse environmental conditions in the field. In this study, we investigated the impact of delayed Sorghum sp. harvest on the physiological and sanitary quality of seeds in four hybrids grown in the tropical soil of the Brazilian Cerrado region. Plants from four Sorghum sp. hybrids (IPA SUDAN 4202, BRS 658, BRS 810, and BRS 373) were grown and submitted to four seed harvest periods (0, 7, 14, and 21 days after stage 9 - seed physiological maturity). The treatments were arranged in a completely randomized block design in a 4 × 4 factorial, with four replicates. At each harvest period, the thousand-seed weight, water content, first count of the germination test, germination, seedling emergence, emergence speed index, seedling dry matter, accelerated aging, electrical conductivity, and sanitary quality of seeds were determined. Seeds of higher physiological and sanitary quality of the IPA SUDAN 4202 and BRS 658 sorghum hybrids can be obtained when the harvest is carried out up to 7 days after the physiological maturity stage. However, the delay in seed harvesting at 14 and 21 days after physiological maturity results in a higher incidence of Colletotrichum sp., Curvularia sp., Rhizoctonia sp., and Alternaria sp. on the seeds of these hybrids. Delaying the harvest of sorghum seeds from 7 days after the physiological maturity stage compromises seed vigor and viability and increases the incidence of pathogens. field study sp region 810 373 0, 0 (0 2 maturity. . maturity) factorial replicates period thousandseed thousand weight content test index matter aging conductivity determined 420 65 However 1 pathogens 81 37 ( 42 6 8 3