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Allophoma brasiliensis J.L.V.R. Carvalho, J.D.P. Bezerra & Souza-Motta is reported for the first time as endophyte from leaves of Capsicum annuum L. (Solanaceae) isolated in an agricultural site from Brazilian Atlantic Forest. For species determination, morphological characters were analysed along with a multigene analysis performed using the ITS region of the rDNA, the partial large subunit nuclear ribosomal RNA gene (LSU rRNA), the partial second largest subunit of the RNA polymerase II gene subunit (rpb2), and the partial β–tubulin gene (tub2). A key to Allophoma Qian Chen & L. Cai species is provided. This new record contributes to the global fungal diversity, indicating a new geographical distribution, and a new lifestyle.

Abstract Climate change is predicted to increase the occurrence of extreme weather events such as heatwaves, which may thereby impact the outcome of plant-herbivore interactions. While elevated temperature is known to directly affect herbivore growth, it remains largely unclear if it indirectly influences herbivore performance by affecting the host plant they feed on. In this study, we investigated how transient exposure to high temperature influences plant herbivory-induced defenses at the transcript and metabolic level. To this end, we studied the interaction between potato (Solanum tuberosum) plants and the larvae of the potato tuber moth (Phthorimaea operculella) under different temperature regimes. We found that P. operculella larvae grew heavier on leaves co-stressed by high temperature and insect herbivory than on leaves pre-stressed by herbivory alone. We also observed that high temperature treatments altered phylotranscriptomic patterns upon herbivory, which changed from an evolutionary hourglass pattern, in which transcriptomic responses at early and late time points after elicitation are more variable than the ones in the middle, to a vase pattern. Specifically, transcripts of many herbivory-induced genes in the early and late defense stage were suppressed by HT treatment, whereas those in the intermediate stage peaked earlier. Additionally, we observed that high temperature impaired the induction of jasmonates and defense compounds upon herbivory. Moreover, using jasmonate-reduced (JA-reduced, irAOC) and -elevated (JA-Ile-elevated, irCYP94B3s) potato plants, we showed that high temperature suppresses JA signaling mediated plant-induced defense to herbivore attack. Thus, our study provides evidences on how temperature reprograms plant-induced defense to herbivores.

Abstract Entomopathogenic nematodes of the genera Steinernema and Heterorhabditis, along with their bacterial symbionts from the genera Xenorhabdus and Photorhabdus, respectively, are important biological control agents against agricultural pests. Rapid progress in the development of genomic tools has catalyzed a transformation of the systematics of these organisms, reshaping our understanding of their phylogenetic and cophlylogenetic relationships. In this review, we discuss the major historical events in the taxonomy and systematics of this group of organisms, highlighting the latest advancements in these fields. Additionally, we synthesize information on nematode–bacteria associations and assess the existing evidence regarding their cophylogenetic relationships.

This cross-sectional study examined the lower limb balance, ankle dorsiflexion, orofacial tissue pressure, and occlusal strength of rugby players. Twenty-six participants were divided into groups: rugby players (n ​= ​13) and healthy sedentary adults (n ​= ​13). Participants underwent an analysis of lower limb balance using a composite score (Y-Balance Test). Ankle dorsiflexion was measured using the Lunge Test. The Iowa Oral Performance Instrument was employed to measure orofacial tissue pressure. Bite force was measured with a dynamometer, and T-Scan assessed occlusal contact distribution. Data were analyzed using the t-test (p ​

Background Among other structures, nuclear grooves are vastly found in papillary thyroid carcinoma (PTC). Considering that the application of artificial intelligence in thyroid cytology has potential for diagnostic routine, our goal was to develop a new supervised convolutional neural network capable of identifying nuclear grooves in Diff-Quik stained whole-slide images (WSI) obtained from thyroid fineneedle aspiration. Methods We selected 22 Diff-Quik stained cytological slides with cytological diagnosis of PTC and concordant histological diagnosis. Each of the slides was scanned, forming a WSI. Images that contained the region of interest were obtained, followed by pre-formatting, annotation of the nuclear grooves and data augmentation techniques. The final dataset was divided into training and validation groups in a 7:3 ratio. Results This is the first artificial intelligence model based on object detection applied to nuclear structures in thyroid cytopathology. A total of 7,255 images were obtained from 22 WSI, totaling 7,242 annotated nuclear grooves. The best model was obtained after it was submitted 15 times with the train dataset (14th epoch), with 67% true positives, 49.8% for sensitivity and 43.1% for predictive positive value. Conclusions The model was able to develop a structure predictor rule, indicating that the application of an artificial intelligence model based on object detection in the identification of nuclear grooves is feasible. Associated with a reduction in interobserver variability and in time per slide, this demonstrates that nuclear evaluation constitutes one of the possibilities for refining the diagnosis through computational models.

El objetivo del trabajo fue estudiar el efecto del almacenamiento al ambiente en la germinación de las semillas de Leucaena leucocephala cv. Cunningham sometidas a hidratación parcial. Los tratamientos fueron: control, sin escarificación (T0); escarificación térmica (ET) con H2O a 80°C, durante dos minutos (T1); ET más hidratación parcial, en bandeja con agua corriente por 28 horas (T2); ET más hidratación parcial, en saco de yute humedecido con agua corriente por 28 horas (T3); ET más hidratación parcial, en bandeja con agua corriente y TMTD al 0,1% (plaguicida) por 28 horas (T4); ET más hidratación parcial, en saco de yute humedecido con agua corriente y TMTD al 0,1% (plaguicida) por 28 horas (T5). Las semillas hidratadas se deshidrataron durante 72 horas al aire y a la sombra, antes de almacenarlas. Se midió la germinación y la viabilidad a 0, 1, 2, 3, 4, 6, 18, 30 y 42 meses. Se utilizó un diseño totalmente aleatorizado y cuatro réplicas por tratamiento. Hubo diferencias significativas (PThe objective of the work was to study the effect of storage under ambient conditions on the germination of seeds from Leucaena leucocephala cv. Cunningham subject to partial hydration. The treatments were: control, no scarification (T0); thermal scarification (TS) with H2O at 80ºC, for two minutes (T1); TS plus partial hydration, on tray with tap water for 28 hours (T2); TS plus partial hydration, in jute sac moist with tap water for 28 hours (T3); TS plus partial hydration in tray with tap water and TMTD at 0,1% (pesticide) for 28 hours (T4); TS plus partial hydration, in jute sac moist with tap water and TMTD at 0,1% (pesticide) for 28 hours (T5). The hydrated seeds were dehydrated during 72 hours exposed to air and under shade, before being stored. Germination and viability were measured after 0, 1, 2, 3, 4, 6, 18, 30 and 42 months. A completely randomized design and four replications per treatment were used. There were significant differences (P

El objetivo de este trabajo fue caracterizar dos procedencias introducidas desde Suramérica (Planta-2 y Planta-3) y tres colectadas en Cuba (SSCS-5, Colón-1 y Las Tunas), de Ricinus communis L. Para ello se consideraron indicadores morfológicos y agroproductivos. Se utilizaron parcelas de 40 m² (área vital), con diez plantas. El diseño fue totalmente aleatorizado y los datos se analizaron a partir de estadígrafos descriptivos. Planta-2 alcanzó la mayor velocidad de crecimiento (2,98 cm/día) y, a los 17 meses, fue superior en cuanto a: el grosor del tallo (17,5 cm); el número de ramas primarias (45), secundarias (41) y terciarias (20); y el grosor de las ramas primarias (5,9 cm). SSCS-5, Colón-1 y Las Tunas mostraron racimos más largos, con un mayor número de frutos; pero fueron superadas por Planta-3 y Planta-2 en el peso de los frutos por racimo (134,9 y 139,0 g, respectivamente), con frutos y semillas más grandes. Las lesiones producidas por insectos y el grado de infestación por microorganismos patógenos no fueron representativos. El mayor rendimiento de semilla (95,1 kg), el de frutos por planta (5,28 kg) y por área (4 398 kg/ha) y el estimado de aceite por unidad de área (1 130,2 kg/ha) se detectaron en Planta-2. Se concluye que estas procedencias poseen características morfoproductivas que las diferencian, y mostraron particularidades relevantes para la producción de aceite, el cual se destina no solo a la producción de biodiesel, sino a múltiples usos a partir de sus derivados. Se recomienda profundizar en estudios sobre la fitotecnia de R. communis, de forma particular en Planta-2; así como introducir tipos medianos que faciliten su cosecha.The objective of this work was to characterize two provenances introduced from South America (Planta-2 and Planta-3) and three provenances collected in Cuba (SSCS-5, Colón-1 and Las Tunas), of Ricinus communis L. For such purpose, morphological and agroproductive indicators were considered. Plots measuring 40 m² (vital area) were used, with ten plants. The design was completely randomized and the data were analyzed from descriptive stadigraphs. Planta-2 reached the highest growth rate (2,98 cm/day) and, at 17 months of age, it was superior regarding: stem diameter (17,5 cm); number of primary (45), secondary (41) and tertiary branches (20); and the diameter of primary branches (5,9 cm). SSCS-5, Colón-1 and Las Tunas showed longer racemes, with a higher number of fruits; but they were surpassed by Planta-3 and Planta-2 in fruit weight per raceme (134,9 and 139,0 g, respectively), with larger fruits and seeds. The lesions caused by insects and the degree of infestation by pathogen microorganisms were not representative. The highest seed yield (95,1 kg), fruit yield per plant (5,28 kg) and per area (4 398 kg/ha) and the estimated oil yield per area unit (1 130,2 kg/ha) were detected in Planta-2. These provenances were concluded to have morpho-productive characteristics that differentiate them from each other, and to show relevant particularities for oil production, which is destined not only for biodiesel production, but also for many uses from its derivatives. To conduct further studies on the management of R. communis, particularly in Planta-2, as well as to introduce medium-sized types that facilitate their harvest, is recommended.

En un suelo ácido (pH ~ 4,9), de baja fertilidad, se estudió una colección de 20 accesiones de Brachiaria brizantha asociadas a Stylosanthes guianensis CIAT-184, con el objetivo de evaluar su comportamiento agronómico durante la etapa de establecimiento. Se utilizaron parcelas de 5 x 4 m, con tres réplicas. Los indicadores medidos y/o estimados fueron: el porcentaje de supervivencia (15, 30 y 45 días), la altura de la planta, la abundancia de hojas, el vigor, las afectaciones provocadas por las plagas y la infestación por enfermedades. Para la interpretación de los resultados se utilizó el análisis de componentes principales. En los primeros 45 días las accesiones CIAT-16317, CIAT-26032, CIAT-16485 y el cv. Mulato alcanzaron los mejores índices de supervivencia (por encima del 90%). Después de los 45 días se detectó una alta variabilidad (90,30%) para las dos primeras componentes. Al agrupar las accesiones se identificó la formación de siete grupos, en algunos de los cuales predominaron individuos de porte alto, y en otros, plantas con buen vigor y hojosidad. De manera general, se puede concluir que hubo un comportamiento aceptable de la asociación entre las accesiones de B. brizantha y S. guianensis CIAT-184, ya que todas en mayor o menor medida cumplimentaron la etapa de establecimiento. Se destacaron las accesiones de los grupos IV, V y VII, ya que mostraron resultados positivos (por encima de la media) en dos indicadores de los tres estimados. Se recomienda dar continuidad a la evaluación de la fase de explotación de este germoplasma con animales, de manera tal que sea posible, en el futuro mediato, seleccionar las accesiones más sobresalientes durante todo el periodo experimental.On a low-fertility, acid soil (pH ~ 4,9), a collection of 20 Brachiaria brizantha accessions associated to Stylosanthes guianensis CIAT-184 was studied, in order to evaluate its agronomic performance during the establishment stage. For such purpose, 5 x 4 m plots were used, with three replications. The measured and/or estimated indicators were: survival percentage (15, 30 and 45 days), plant height, leaf abundance, vigor, affectations caused by pests and infestation by diseases. For interpreting the results, the principal component analysis was used. In the first 45 days the accessions CIAT-16317, CIAT-26032, CIAT-16485 and the cv. Mulato reached the best survival rates (over 90%). After 45 days a high variability (90,30%) was detected for the first two components. When grouping the accessions, the formation of seven groups was identified, in some of which tall individual plants prevailed, and in others, plants with good vigor and leafiness were predominant. In general, it can be concluded that there was an acceptable performance of the association between the B. brizantha accessions and S. guianensis CIAT-184, because all of them to a larger or lesser extent- fulfilled the establishment stage. The accessions of groups IV, V and VII stood out, because they showed positive results (over the mean) in two indicators from the three estimated ones. To continue the evaluation of the exploitation stage of this germplasm with animals is recommended, so that it is possible, in the near future, to select the most outstanding accessions throughout the experimental stage.

Este trabajo tuvo como objetivo caracterizar los cambios y la tendencia de indicadores relacionados con la estructura, la población y la composición en 19 accesiones de Panicum maximum cuando fueron sometidas a condiciones de pastoreo simulado. Las rotaciones se hicieron cada 32-40 días en el periodo lluvioso y 60-70 días en el poco lluvioso, con intensidad de pastoreo de 80-135 UGM/ha/día (los dos primeros años) y 120-160 UGM/ha/día (tercer año). Se utilizó un diseño de bloques al azar con tres repeticiones. Aunque en todos los tratamientos disminuyó la relación vástagos vivos/vástagos muertos, este cociente fue superior a uno, por lo que el ritmo de sustitución de vástagos fue favorable. En el 84,2% de los tratamientos se incrementó el número de macollas con relación a el estatus inicial. El porcentaje de arvenses aumentó con las rotaciones, pero ninguno de los tratamientos alcanzó un estado de deterioro avanzado. En este indicador se destacaron los tipos gigantes CIH-13, SIH-697, CIH-3, CC-1146 y SIH-10, con valores que variaron entre 4,6 y 14,1%, así como los tipos medianos CIH-15 y Tardío pequeño, con 10 y 12,3%, respectivamente. Se concluye que el germoplasma evaluado mostró valores adecuados, en función de los indicadores relacionados con la estructura de la macolla, la población y el porcentaje de invasión de las especies arvenses, aunque se identificó un alto contraste entre los tipos gigantes y medianos y dentro de estos grupos. Se sugiere analizar el resto de los indicadores productivos y con ello determinar los tipos más sobresalientes, sobre la base de los resultados en todos los indicadores incluidos.The objective of this work was to characterize the changes and trend of indicators related to the structure, population and composition in 19 Panicum maximum accessions under simulated grazing conditions. The rotations took place every 32-40 days in the rainy season and 60-70 days in the dry season, with grazing intensity of 80-135 animals/ha/day (the first two years) and 120-160 animals/ha/year (third year). A randomized block design was used with three repetitions. Although in all treatments the live shoots/dead shoots ratio decreased, this quotient was higher than one, for which the substitution rate of the shoots was favorable. In 84,2% of the treatments, the number of tufts increased as compared to the initial status. The weed percentage increased with the rotations, but none of the treatments reached an advanced deterioration status. In this indicator the giant types CIH-13, SIH-697, CIH-3, CC-1146 and SIH-10 stood out, with values that varied between 4,6 and 14,1%, as well as the medium types CIH-15 and Tardío pequeño with 10 and 12,3%, respectively. The evaluated germplasm was concluded to show adequate values, regarding the indicators related to the structure of the tuft, population and percentage of weed invasion; although a high contrast was identified between giant and medium types and within these groups. To analyze the other productive indicators is suggested in order to determine the most outstanding types, based on the results in all the included indicators.

El artículo brinda experiencias del proyecto internacional BIOMAS-CUBA en la implementación de alternativas de suministro de energía a partir de la biomasa en el medio rural, que sean compatibles con la seguridad alimentaria y la sostenibilidad ambiental. Estas experiencias se enmarcan entre 2009 y 2011, en el marco del concepto de la finca agroenergética, y están relacionadas con procesos de investigación e innovación tecnológica asociados a: la evaluación morfológica, productiva y química de germoplasma de plantas oleaginosas no comestibles con potencial para producir biodiesel, etanol y otros productos; la siembra y manejo agrícola de asociaciones de Jatropha curcas y 21 cultivos alimenticios; el beneficio y extracción de aceite de semillas de Jatropha; la caracterización físico-química de dicho aceite; la producción de biodiesel y sus coproductos; la producción de biogás a partir de excretas y de bioproductos y bioabonos, con los efluentes de biodigestores; la gasificación de biomasa leñosa para generar electricidad; la caracterización y clasificación de sistemas integrados para la producción de alimentos y energía. Asimismo, los estudios socioeconómicos y ambientales permitieron apreciar una adecuada factibilidad económico-financiera, incrementos notables en la producción de alimentos, la formación del capital humano y la mejora de la calidad de vida de las personas, un positivo impacto ambiental, y una sustitución de portadores energéticos y fertilizantes convencionales.This paper provides experiences of the international project BIOMAS-CUBA in the implementation of energy supply alternatives from biomass in rural areas, which are compatible to food security and environmental sustainability. These experiences are comprised between 2009 and 2011, within the agroenergetic farm concept, and are related to research and technological innovation processes associated to: the morphological, productive and chemical evaluation of germplasm of non-edible oil plants with potential to produce biodiesel, ethanol and other products; the planting and agricultural management of associations of Jatropha curcas and 21 food crops; the cleaning and oil extraction of Jatropha seeds; the physical-chemical characterization of such oil; the production of biodiesel and its co-products; the biogas production from excreta and bioproducts and biofertilizers, with the effluents of biodigesters; the gasification of ligneous biomass to generate electricity; the characterization and classification of integrated food and energy production systems. Likewise, the socioeconomic and environmental studies allowed appreciating adequate economic-financial feasibility, remarkable increases in food production, the formation of human capital and the improvement of the people's quality of life, a positive environmental impact and a substitution of energy porters and conventional fertilizers.

El objetivo de este trabajo fue caracterizar la variabilidad morfológica y productiva de procedencias de Jatropha curcas. Para ello se midió o estimó: la altura; el grosor de las ramas primarias y del tallo; la altura de la primera rama; las enfermedades; el número de ramas primarias, secundarias y terciarias; el número y el peso de los frutos; el rendimiento de semillas; el peso de 100 semillas; las dimensiones de la semilla y el contenido de aceite. Para interpretar los resultados se utilizó ACP y análisis de conglomerados. La altura fue el indicador más variable, seguido por el grosor de las ramas primarias, el número de ramas secundarias y primarias, y el grosor del tallo, los cuales explicaron el 57,7% de la variabilidad. Sobre la base de estos indicadores se formaron seis grupos. Los valores extremos superiores, en todos los indicadores morfológicos, se encontraron en el grupo I (SSCS-3), y los inferiores en el grupo IV (SSCS-7 y SSCS-6). Solo seis de las diez procedencias sembradas produjeron frutos; mientras que las plantadas lo hicieron en todos los casos. De las sembradas sobresalieron: San Miguel, D-1 y SSCS-3, con rendimientos estimados de 2 325; 243 y 169 kg de semilla/ha; y de las plantadas: Cabo Verde, SSCE-10 y SSCE-7 con 814; 327 y 93,2 kg de semilla/ha, respectivamente. En la SSCE-10 y en la Cabo Verde el porcentaje de aceite alcanzó un 32,8 y 35,0%, respectivamente. Los resultados permitieron identificar las procedencias sobresalientes, tanto en los indicadores morfológicos (SSCS-3) como en los productivos (Cabo Verde, SSCE-10 y San Miguel).The objective of this work was to characterize the morphological and productive variability of Jatropha curcas provenances. For that purpose the following indicators were measured or estimated: height; diameter of primary branches and stem; height of the first branch; diseases; number of primary, secondary and tertiary branches; fruit number and weight; seed yield; weight of 100 seeds; seed size and oil content. In order to interpret the results PCA and cluster analysis were used. Height was the most variable indicator, followed by diameter of primary branches, number of secondary and primary branches and stem diameter, which accounted for 57,7% of the variability. Based on these indicators six groups were formed. The highest values, in all morphological indicators, were found in group I (SSCS-3), and the lowest ones in group IV (SSCS-7 and SSCS-6). Only six from the ten seeded provenances produced fruits; while the planted ones did it in all cases. Among the seeded ones the following stood out: San Miguel, D-1 and SSCS-3, with estimated yields of 2 325; 243 and 169 kg of seed/ha; and in the planted ones: Cabo Verde, SSCE-10 and SSCE-7 with 814; 327 and 93,2 kg of seed/ha, respectively. In SSCE-10 and Cabo Verde the oil percentage reached 32,8 and 35,0%, respectively. The results allowed identifying the outstanding provenances, in the morphological (SSCS-3) as well as the productive indicators (Cabo Verde, SSCE-10 and San Miguel).

El objetivo de este trabajo fue colectar material de J. curcas con características morfológicas adecuadas para la producción de semilla, así como determinar su comportamiento en la fase de vivero y la de establecimiento. En el vivero se observó variación en los días necesarios para el arraigamiento de los propágulos (14 a 35 días) y en la emergencia de las plántulas (7 a 28 días). La supervivencia de los propágulos fluctuó entre 73 y 100%; mientras que a partir de semilla estuvo entre 26,6 y 85,0%. La supervivencia en la fase de campo varió entre 45,4 y 93,3% en las procedencias trasladadas por propágulos, pero en la mayoría resultó inferior a la que se detectó en el vivero. En las procedencias sembradas directamente también se detectó variación en la supervivencia, pero el número de plantas emergidas a los 56 días fue alto. En estas condiciones se mantuvo un patrón de variación similar en el porcentaje de plantas arraigadas y de supervivencia, pero fue evidente el efecto del estrés causado por el traslado. Se concluye que la edad de las plantas y de las partes elegidas en el material donante, así como la calidad de la semilla, pudieron influir en la variación de los días necesarios para el arraigamiento o la emergencia y en el porcentaje de supervivencia. Se recomienda utilizar el procedimiento descrito para la colecta de J. curcas, enfatizando en la vía vegetativa, con el fin de acceder a procedencias con características adecuadas para la producción de semilla y con ello mantener el genotipo de los materiales colectados.The objective of this work was to collect J. curcas material with adequate morphological characteristics for seed production, as well as to determine its performance in the nursery and establishment stages. In nursery variation was observed in the necessary days for the rooting of the propagules (14 to 35 days) and in seedling emergence (7 to 28 days). The propagule survival fluctuated between 73 and 100%; while starting from seed it was between 26,6 and 85,0%. The survival in the field stage varied between 45,4 and 93,3% in the provenances transferred by propagules, but in most it turned out to be lower than the one detected in the nursery. In the provenances directly sown variation was also detected in survival, but the number of plants emerged after 56 days was high. Under these conditions a similar variation pattern was maintained in the percentage of rooted plants and survival, but the effect of the stress caused by the transfer was evident. It is concluded that the age of the plants and the parts selected in the donor material, as well as seed quality, could have influenced the variation of the necessary days for rooting or emergence and the survival percentage. Using the procedure described for the collection of J. curcas is recommended, emphasizing the vegetative way, in order to have access to provenances with adequate characteristics for seed production and with it maintain the genotype of the collected materials.

Customer Lifetime Value (CLV) represents the total worth of a customer to a company over time, aiding businesses in resource allocation and tailored marketing for profitability. This literature review fills a research gap by examining how customer risk factors are integrated into CLV calculations. We conducted a systematic literature review across databases, adhering to strict criteria for relevance and quality. The review analyzed CLV methodologies and outcomes, highlighting the use of mean–variance analysis to optimize customer portfolios, with customer income fluctuations identified as a major risk factor. The study also explores the evolution of CLV research, particularly in the application of Machine Learning (ML) for risk-adjusted CLV. Our findings offer a comprehensive overview, laying the groundwork for future research and helping businesses refine risk management strategies, identify high-risk customers, and enhance customer value through more dynamic, data-driven models.

In this era of Big Data and the advancement of sophisticated analytical techniques, the financial industry has the capacity to implement innovative technologies within their systems to derive crucial insights about their clientele and vigilantly monitor their activities. This landscape has seen the emergence and rise of two significant applications, namely, customer segmentation systems and early warning systems. Therefore, this study presents a systematic literature review on the automation of customer segmentation and early warning techniques with a focus on managing credit portfolio entities. The research delves into a multitude of scholarly articles from three distinct perspectives: charting the dominant trends within the literature, unpacking the overarching themes, and critically examining the integration of early warning signals within customer clustering applications. Furthermore, the review reveals a noticeable dearth of studies probing the synergistic application of these two systems. Despite their independent effectiveness in risk management and targeted marketing strategies respectively, an integrated approach holds potential for bolstering financial stability and tailoring customer service. Thus, this review stands as a significant academic contribution, advocating an integrated application of these systems within the financial industry. The findings provide a novel foundation for future research and practical applications, potentially redefining strategies within the financial sector.

Abstract The discovery of novel bioactive compounds produced by microorganisms holds significant potential for the development of therapeutics and agrochemicals. In this study, we conducted genome mining to explore the biosynthetic potential of entomopathogenic bacteria belonging to the genera Xenorhabdus and Photorhabdus. By utilizing next-generation sequencing and bioinformatics tools, we identified novel biosynthetic gene clusters (BGCs) in the genomes of the bacteria, specifically plu00736 and plu00747. These clusters were identified as unidentified non-ribosomal peptide synthetase (NRPS) and unidentified type I polyketide synthase (T1PKS) clusters. These BGCs exhibited unique genetic architecture and encoded several putative enzymes and regulatory elements, suggesting its involvement in the synthesis of bioactive secondary metabolites. Furthermore, comparative genome analysis revealed that these BGCs were distinct from previously characterized gene clusters, indicating the potential for the production of novel compounds. Our findings highlighted the importance of genome mining as a powerful approach for the discovery of biosynthetic gene clusters and the identification of novel bioactive compounds. Further investigations involving expression studies and functional characterization of the identified BGCs will provide valuable insights into the biosynthesis and potential applications of these bioactive compounds.

Resumo O estudo teve como objetivo avaliar a deposição de serrapilheira e o aporte de nutrientes em três modelos de revegetação e uma área de floresta secundária na Reserva Biológica de Poço das Antas, Silva Jardim (RJ). O material foi coletado mensalmente entre os meses de novembro de 2000 a outubro de 2001. A deposição anual do modelo adensado foi de 9,69 t ha-1, 10,38 t ha-1 no modelo semi-adensado, 9,97 t ha-1 no modelo tradicional, e na mata secundária de 12,22 t ha-1, não havendo diferença significativa entre os modelos, sendo os valores encontrados muito superiores a outros estudos em florestas tropicais. A fração foliar foi a mais representativa com valores entre 63,1 a 76,2%. A deposição foi sazonal nas áreas de floresta secundária e no sistema tradicional semidenso. Em relação ao aporte de nutrientes pode se observar maiores valores de N do que P e K.

ABSTRACT A recent study published in mBio by Nemet et al. revealed the critical role played by two gut microbiota members in producing the metabolites indoxyl sulfate (IS) and p-cresol sulfate (pCS) (I. Nemet, M. Funabashi,X. S. Li, M. Dwidar, et al., 2023, mBio 14:e01331-23, https://doi.org/10.1128/mbio.01331-23). Understanding microbial pathways leading to IS and pCS production is crucial because they are connected to a pre-thrombotic profile, and having high levels of these metabolites increases the risk of cardiovascular diseases (CVD). Hence, this study can offer vital insights into assessing the risk for CVD and identifying potential treatment targets for this disease.

In this study, ultrasound (US) was evaluated for As, Cd, Pb, Mn, Sr and V extraction from seaweed samples. The following parameters of ultrasound-assisted extraction (UAE) using an US bath were: frequency (25 to 130 kHz), amplitude (30 to 100%), temperature (30 to 80 °C), sample mass (50 to 200 mg), extractant concentration (1 to 3 mol L−1 of HNO3) and treatment time (5 to 30 min). Acoustic density and power density distribution were calculated using the calorimetric method and mapping of the acoustic pressure distribution was also evaluated. The optimized UAE conditions were 200 mg of sample in 10 mL of 2 mol L−1 HNO3 and 30 min of sonication in a 25 kHz US bath (37.2 ± 4.0 W L−1) at 70% of amplitude and 70 °C. Analytes were quantified using inductively coupled plasma mass spectrometry and results were compared with values obtained using “silent” conditions (magnetic or mechanical stirring at 500 rpm, and without stirring), and a reference method based on microwave-assisted wet digestion (MAWD). The UAE method demonstrated the best extraction efficiency (higher than 95%) for all analytes, especially for As, Cd and V, with lower standard deviations (up to 5%) and lower blank values in comparison with the silent conditions. The proposed UAE method was more advantageous than the reference method, being faster, simpler, safer, more environmentally friendly, and with higher detectability (lower limits of quantification, from 0.0033 to 1.34 µg g−1). In addition, negligible blank values were obtained for UAE and no interference were observed in the determination step. Furthermore, the optimized UAE method was applied for Antarctic seaweed samples and comparison with results obtained by MAWD was satisfactory. In this sense, UAE is demonstrated to be a suitable option for sample preparation of seaweed samples and further determination of environmentally critical elements avoiding the use of concentrated reagents as in the MAWD reference method.

Vibration signals extracted from structures across diverse health conditions have become indispensable for monitoring structural integrity. These datasets represent a resource for real-time condition monitoring, enabling the precise detection and diagnosis of system anomalies. This paper aims to enrich the scientific community's database on structural dynamics and experimental methodologies pertinent to system modelling. Leveraging experimental measurements obtained from mass-reinforced beams, these datasets validate numerical models, refine identification techniques, quantify uncertainties, and continuously foster machine learning algorithms' evolution to monitor structural integrity. Furthermore, the beam dataset is data-driven and can be used to develop and test innovative structural health monitoring strategies, specifically identifying damages and anomalies within intricate structural frameworks. Supplemental datasets like Mass-position and damage index introduce parametric uncertainty into experimental and damage identification metrics. Thereby offering valuable insights to elevate the efficacy of monitoring and control techniques. These comprehensive tests also encapsulate paramedic uncertainty, providing robust support for applications in uncertainty quantification, stochastic modelling, and supervised and unsupervised machine learning methodologies.

Abstract Background Nematodes of the genus Heterorhabditis are important biocontrol agents as they form a lethal combination with their symbiotic Photorhabdus bacteria against agricultural insect pests. This study describes a new species of Heterorhabditis. Methods Six Heterorhabditis nematode populations were recovered from agricultural soils in Jammu and Kashmir, India. An initial examination using mitochondrial and nuclear genes showed that they belong to a new species. To describe this new species, a variety of analyses were conducted, including reconstructing phylogenetic relationships based on multiple genes, characterizing the nematodes at the morphological and morphometric levels, performing self-crossing and cross-hybridization experiments, and isolating and characterizing their symbiotic bacteria. Results The newly discovered species, Heterorhabditis casmirica n. sp., shares 94% mitochondrial cytochrome C oxidase subunit I gene (COI) sequence identity with Heterorhabditis bacteriophora and Heterorhabditis ruandica, and 93% with Heterorhabditis zacatecana. Morphologically, it differs from H. bacteriophora in its infective juvenile phasmids (present vs. inconspicuous) and bacterial pouch visibility in the ventricular portion of the intestine (invisible vs. visible); genital papilla 1 (GP1) position (at manubrium level vs. more anterior), and in its b ratio (body length/neck length), c ratio (tail length/bulb width), and D% [(excretory pore/neck length) × 100]. Other morphological differences include anterior end to the nerve ring distance (77–100 vs. 121–130 μm), V% [(anterior end of vulva/body length) × 100] (46–57 vs. 41–47) in hermaphroditic females; rectum size (slightly longer than the anal body diameter vs. about three times longer), phasmids (smaller vs. inconspicuous), body length (0.13–2.0 vs. 0.32–0.39 mm), body diameter (73–150 vs. 160–220 μm), anterior end to the excretory pore distance (135–157 vs. 174–214 μm), and demanian ratios in amphimictic females. Morphological differences with H. ruandica and H. zacatecana were also observed. Furthermore, H. casmirica n. sp. did not mate or produce fertile progeny with other Heterorhabditis nematodes reported from India. It was also discovered that H. casmirica n. sp. is associated with 'Photorhabdus laumondii subsp. clarkei symbiotic bacteria. Conclusions The discovery of H. casmirica n. sp. provides novel insights into the diversity and evolution of Heterorhabditis nematodes and their symbiotic bacteria. This new species adds to the catalog of entomopathogenic nematodes in India. Graphical Abstract

RESUMO Este artigo registra pela primeira vez a ocorrência da cigarrinha Cephisus siccifolius (Walker, 1851) no Estado da Bahia, Brasil. Adultos deste inseto foram encontrados em cinco municípios da Região Sul do Estado. A espécie é fototrópica positiva para luz artificial.

Iatrogenic vascular injuries include an extremely broad group of lesions with multiple etiology and polymorphic manifestations. We present a series of 44 patients with iatrogenic vascular lesions that result from arterial and venous catheterizations and surgical interventions. The arterial catheterization for coronariography and arteriography and orthopaedic surgery were the agents that most frequently caused vascular injury. Arterial and venous reconstructive surgery were the predominant treatment procedures. In our series, morbidity and mortality were 4.6% and 2.3%, respectively.

Objective: Describe the epidemiological profile and social-economic burden that hydrocephalus patients represent to the national public health system, using data available at the online database of the Brazilian Health Ministry (DataSUS). Methods: This is a populational study based on descriptive statistics of all clinical and surgical appointments included in the DataSUS database. Data included herein were collected between 2015 and 2021 and subdivided into three main groups, related to hydrocephalus incidence and mortality, hospitalizations, and financial costs. Results: In the study period, 3993 new cases of congenital hydrocephalus were diagnosed, with 6051 deaths overall. The mortality rate in the country was 1.5/100000 live births and the prevalence was 0.374/100000 inhabitants. The number of hospitalizations resulting from treatment procedures and complications of hydrocephalus was 137,880 and there was a reduction of up to 27.2% during the SARS-CoV-2 pandemics concerning previous years. Total costs for hydrocephalus management in the country amounted to 140,610,585.51 dollars. Conclusions: Hydrocephalus has a significant impact on public health budgets and pediatric mortality rates; however, it is probably underestimated, due to the paucity of demographic data and epidemiological studies in Latin America and, specifically, in Brazil. The dataSUS also has several limitations in accessing certain data related to hydrocephalus, making it difficult to have a more assertive understanding of the disease in Brazil. The results of this study provide important guidance for future research projects in clinical and experimental hydrocephalus and also the creation of public policies for better governance and care of hydrocephalus patients.

The classification of Microbispora, a bacterial genus of significant ecological, agricultural, biotechnological, and clinical importance, has traditionally been carried out based on 16S rRNA gene sequences or phenotypic characteristics, which may lead to equivocal conclusions and it is not in line with the current standards. Moreover, some of the recent species descriptions have not been made using whole genome sequences (WGS), or when used, not all the species were included in the analyses. Consequently, some of the taxonomic conclusions drawn are equivocal, and therefore some currently accepted species should be synonymized. In this study, we revised the taxonomy of the genus Microbispora using digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values, and by reconstructing phylogenetic relationships using whole genome sequences. Based on the clear phylogenomic separations and on the sequence divergence values, we propose to elevate Microbispora rosea subsp. rosea and Microbispora rosea subsp. aerata to the species level, and therefore to create Microbispora aerata sp. nov. with JCM 3076T (= DSM 43176T = ATCC 15448T = IFO 14624T = NBRC 14624T = VKM Ac-1507T) as the type strain. Hence, with this proposition, the correct name for Microbispora rosea subsp. rosea is M. rosea. Furthermore, we propose to reclassify M. camponoti as a subspecies within M. bryophytorum. Consequently, we propose the creation of the following two subspecies: Microbispora bryophytorum subsp. bryophytorum subsp. nov. with DSM 46710T (= CGMCC 4.7138T = NEAU TX2-2T) as the type strain, and Microbispora bryophytorum subsp. camponoti subsp. nov., comb. nov. with DSM 2C-HV3T (= DSM 100527T = CGMCC 4.7281T) as the type strain. In addition, we propose to reinstate M. amethystogenes as an independent species and not as a M. rosea synonym, and reclassify "M. cellulosiformans" as a subspecies within M. amethystogenes. Hence, we propose the creation of the following two subspecies: Microbispora amethystogenes subsp. amethystogenes subsp. nov. with NBRC 101907T (= DSM 43164T = JCM 3021T = NRRL B-2637T) as the type strain, and Microbispora amethystogenes subsp. cellulosiformans subsp. nov., comb. nov. with Gxj-6T (= DSM 109712T = CGMCC 4.7605T) as the type strain. Lastly, we propose M. fusca NEAU-HEGS1-5T and "M. tritici" MT50T as later homotypic synonyms of M. triticiradicis NEAU-HRDPA2-9T.

Renal cell carcinoma (RCC) is the most common type of cancer in kidney and is often diagnosed in advanced stages. Until now, there is no reliable biomarker to assess tumor prognosis during histopathological diagnosis. The Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) overexpression has been suggested as prognostic indicator for RCC, however, its protein profile needs to be clarified. This study investigated the MTHFD2 expression in different RCC cohorts, associating it with tumor characteristics and prognostic factors. Gene expression comparisons between non-neoplastic (NN) and tumor samples, as well as patients' survival analysis, were assessed using KM-Plotter tool. MTHFD2 protein pattern was evaluated in 117 RCC by immunohistochemistry and associations with prognosis, clinical and pathological data were investigated. The tumors exhibited higher MTHFD2 transcript levels than NN, being even higher in the metastatic group. Opposite gene expression patterns were found among clear cell renal cell carcinoma (ccRCC) and pappilary renal cell carcinoma (pRCC) subtypes, showing higher and lower expressions compared to NN samples respectively. Overexpression was associated with shorter overall survival for ccRCC and pRCC subtypes, and shorter recurrence-free survival for pRCC. The immunolabeling profile varied according to tumor subtypes, with lower intensity and expression scores in ccRCC compared to pRCC and to chromophobe renal cell carcinoma (chRCC). MTHFD2 protein expression was associated with larger tumors and higher Fuhrman grades. Although prognostic value of protein immunostaining was not confirmed, patients with higher MTHFD2 tended to have lower survival rates in the pRCC group. The results highlight MTHFD2 different patterns according to RCC histological subtypes, revealing marked variations at both the genetic and protein levels. The mRNA indicated tumor prognosis, and greater expression in the tumor samples. Although MTHFD2 immunolabeling suggests tumor aggressiveness, it needs to be validated in other cohorts as potential prognostic factor.

Con el objetivo de evaluar la dinámica de crecimiento de 24 accesiones del género Brachiaria spp., se desarrolló la presente investigación en la región de Barrancabermeja, Santander, Colombia. Se utilizó un diseño experimental completamente aleatorizado, en 72 parcelas de 21 m2 cada una y tres réplicas (parcelas) para cada tratamiento. Las accesiones fueron agrupadas según los hábitos de crecimiento en: estoloníferas, decumbentes y erectas, y se determinó la tasa de crecimiento en función de la altura del pasto. Las accesiones con mejor crecimiento durante la investigación fueron: de las estoloníferas, B. dictyoneura CIAT-6133; de las de hábito decumbente, B. decumbens CIAT-606; y de las de crecimiento erecto, B. brizantha CIAT-16113, CIAT-26110, CIAT-26318 y CIAT-16322. Algunas accesiones no tuvieron un buen comportamiento, al parecer por las condiciones edafoclimáticas a las que fueron sometidas. Entre ellas se encuentran B. dictyoneura CIAT-16871, B. ruziziensis CIAT-26180 y B. brizantha CIAT-16212, 26124 y 26427.In order to evaluate the growth dynamics of 24 accessions of the genus Brachiaria spp., this study was conducted in the Barrancabermeja region, Santander, Colombia. A completely randomized design was used, in 72 plots of 21 m2 each and three replications (plots) for each treatment. The accessions were grouped according to the growth habits into: stoloniferous, decumbent and erect, and the growth rate regarding pasture height was determined. The accessions with best growth during the study were: stoloniferous, B. dictyoneura CIAT-6133; among those of decumbent habit, B. decumbens CIAT-606; and with erect growth, B. brizantha CIAT-16113, CIAT-26110, CIAT-26318 and CIAT-16322. Some accessions did not have a good performance, seemingly due to the edaphoclimatic conditions to which they were subject. Among them are: B. dictyoneura CIAT-16871, B. ruziziensis CIAT-26180 and B. brizantha CIAT-16212, 26124 and 26427.

El presente trabajo tuvo como objetivo crear una metodología de claves interactivas a partir de la reconstrucción de claves de texto publicadas. Se utilizó, como modelo, la clave general del libro "Árboles de Cuba", en el que se explica la técnica de construcción de claves de texto por el método tradicional; en él aparecen importantes recursos fitogenéticos arbóreos y arbustivos forrajeros y con otros usos, los cuales sirvieron de base. Se utilizó el procesador de texto Microsoft Office Word 2003. Se revisaron, además, numerosos materiales bibliográficos que permitieron acceder a una amplia información sobre los taxones arbóreos, arbustivos forrajeros y con otros usos, la que fue compilada y ordenada. El uso de esta metodología facilita la consecución del engorroso trabajo de mesa que presupone el uso de claves construidas por el método tradicional. Permite desarrollar habilidades en la identificación y caracterización de los recursos vegetales y puede utilizarse para reconstruir claves interactivas de otros grupos biológicos clasificados dicotómicamente. Se recomienda la consulta de este material a todos aquellos especialistas que estén relacionados con las actividades de identificación y caracterización de la biodiversidad vegetal u otros seres vivos; editar las claves reconstruidas para los recursos fitogenetéticos arbóreos y arbustivos forrajeros y de otros usos; así como crear software especializados a partir de claves interactivas reconstruidas sobre la base de esta metodología.The objective of this work was to create a methodology of interactive keys from the reconstruction of published text keys. The general key of the book "Árboles de Cuba" (Trees from Cuba), in which the technique of building text keys through the traditional method is explained, was used as a model; in this book there are important tree and shrub genetic resources for forage and other usages, which served as basis. The text processor Microsoft Office Word 2003 was used. Many bibliographic materials were also reviewed, giving access to wide information about tree and shrub taxa for forage and other usages, which was compiled and arranged. The use of this methodology facilitates the completion of the bothersome table work presupposed by the use of keys built by the traditional method. It allows developing skills in the identification and characterization of plant resources and it can be used to reconstruct interactive keys of other biological groups dichotomously classified. The consultation of this material is recommended to all those specialists who are related to the activities of identification and characterization of plant biodiversity or other living beings; it is also recommended to edit the reconstructed keys for tree and shrub genetic resources for forage and other usages; as well as to create specialized software from reconstructed interactive keys based on this methodology.

El objetivo de este trabajo fue determinar y cuantificar las especies que forman parte de la diversidad de la flora en ocho fincas ganaderas o integrales, vinculadas al Centro Local de Innovación Agropecuaria de Matanzas. Para ello se utilizó un diseño muestral sistemático; el tamaño de la muestra no fue inferior a 0,5%. En general, existió una alta diversidad para todas las fincas. En tres de las ocho fincas monitoreadas se encontraron 30 o más especies; en otras tres este número fluctuó entre 19 y 26; mientras que en las dos restantes se contabilizaron 13 y 15 especies, respectivamente. Ello se correspondió con los índices de riqueza, que estuvieron entre 2,03 y 5,22. Existió superioridad numérica de las gramíneas y de las leguminosas sobre las especies de otras familias, cuyo número fluctuó entre una y seis especies (cuatro o menos en el 75% de las fincas). Los mayores valores de dispersión se encontraron en las gramíneas, cuyos índices fueron superiores al 60% y de más del 80% para dos de las fincas. Se sugiere hacer un análisis casuístico, en cada finca, para determinar las futuras estrategias, incluyendo la erradicación parcial y mejora de la cubierta vegetal, o su erradicación y retransformación total, variantes que decidirán los productores respaldados por un asesoramiento.The objective of this work was to determine and quantify the species that are part of the flora diversity in eight livestock production or integral farms, linked to the Local Agricultural Innovation Center of Matanzas. For that purpose, a systematic sampling design was used; the sample size was not lower than 0,5%. In general, there was high diversity for all farms. In three of the eight monitored farms 30 or more species were found; in other three this number fluctuated between 19 and 26; while in the other two 13 and 15 species were counted, respectively. This was in correspondence with the richness values, which were between 2,03 and 5,22. There was numeric superiority of grasses and legumes over the species from other families, which number oscillated between one and six species (four or less in 75% of the farms). The highest dispersion values were found in the grasses, higher than 60% and more than 80% for two farms. The performance of a casuistic analysis, in each farm, is suggested in order to determine the future strategies, including the partial eradication and improvement of the plant cover, or its eradication and total retransformation, variants that will be decided by the farmers supported by advice.

Abstract Background Nosocomial sepsis is a major healthcare issue, but there are few data on estimates of its attributable mortality. We aimed to estimate attributable mortality fraction (AF) due to nosocomial sepsis. Methods Matched 1:1 case–control study in 37 hospitals in Brazil. Hospitalized patients in participating hospitals were included. Cases were hospital non-survivors and controls were hospital survivors, which were matched by admission type and date of discharge. Exposure was defined as occurrence of nosocomial sepsis, defined as antibiotic prescription plus presence of organ dysfunction attributed to sepsis without an alternative reason for organ failure; alternative definitions were explored. Main outcome measurement was nosocomial sepsis-attributable fractions, estimated using inversed-weight probabilities methods using generalized mixed model considering time-dependency of sepsis occurrence. Results 3588 patients from 37 hospitals were included. Mean age was 63 years and 48.8% were female at birth. 470 sepsis episodes occurred in 388 patients (311 in cases and 77 in control group), with pneumonia being the most common source of infection (44.3%). Average AF for sepsis mortality was 0.076 (95% CI 0.068–0.084) for medical admissions; 0.043 (95% CI 0.032–0.055) for elective surgical admissions; and 0.036 (95% CI 0.017–0.055) for emergency surgeries. In a time-dependent analysis, AF for sepsis rose linearly for medical admissions, reaching close to 0.12 on day 28; AF plateaued earlier for other admission types (0.04 for elective surgery and 0.07 for urgent surgery). Alternative sepsis definitions yield different estimates. Conclusion The impact of nosocomial sepsis on outcome is more pronounced in medical admissions and tends to increase over time. The results, however, are sensitive to sepsis definitions.

Four bacterial strains, A-IN1T, A-TC2T, E-TC7T, and K-TC2T, isolated from soil-borne nematodes of the species Oscheius tipulae and Acrobeloides bodenheimeri, were found to represent new species of the genera Acinetobacter, Alcaligenes, Enterobacter, and Kaistia, respectively. In this study, we described these new species using a polyphasic taxonomic approach that included whole-genome and whole-proteome phylogenomic reconstructions, core genome sequence comparisons, and phenotypic characterization. Phylogenomic reconstructions using whole-genome and whole-proteome sequences show that A-IN1T is closely related to Acinetobacter guillouiae DSM 590T and to Acinetobacter bereziniae LMG 1003T. The dDDH values between A-IN1T and these latest strains are 25.1 and 39.6%, respectively, which are below the 70% divergence threshold for prokaryotic species delineation. A-TC2T is closely related to Alcaligenes faecalis subsp. faecalis DSM 30030T and to Alcaligenes faecalis subsp. phenolicus DSM 16503T. The dDDH values between A-TC2T and these latest strains are 47.0 and 66.3%, respectively. In addition, the dDDH values between Alcaligenes faecalis subsp. faecalis DSM 30030T, Alcaligenes faecalis subsp. phenolicus DSM 16503T, and Alcaligenes faecalis subsp. parafaecalis are always lower than 70%, demonstrating that the three strains represent species within the genus Alcaligenes rather than subspecies within Alcaligenes faecalis. E-TC7T is closely related to Enterobacter kobei DSM 13645T, Enterobacter chuandaensis 090028T, and to Enterobacter bugandensis STN0717-56T. The dDDH values between E-TC7T and these strains are 43.5, 42.9, and 63.7%, respectively. K-TC2T is closely related to Kaistia terrae DSM 21341T and to Kaistia defluvii JCM 18034T. The dDDH values between these strains are 29.2 and 30.7%, respectively. Several biochemical tests allow to differentiate the type strains of the newly described species from the type strains of their more closely related species. Based on the results of this polyphasic taxonomic approach, the following new species are proposed: Acinetobacter nematophilus sp. nov. with A-IN1T (=CCM 9231T =CCOS 2018T) as the type strain, Alcaligenes nematophilus sp. nov. with A-TC2T (=CCM 9230T =CCOS 2017T) as the type strain, Enterobacter nematophilus sp. nov. with E-TC7T (=CCM 9232T =CCOS 2020T) as the type strain, and Kaistia nematophila sp. nov. with K-TC2T (=CCM 9239T =CCOS 2022T) as the type strain. In addition, we propose the elevation of Alcaligenes faecalis subsp. faecalis, Alcaligenes faecalis subsp. parafaecalis, and Alcaligenes faecalis subsp. phenolicus to the species level. Therefore, we propose the creation of Alcaligenes parafaecalis sp. nov. with DSM 13975T as the type strain, and Alcaligenes phenolicus sp. nov. with DSM 16503T as the type strain. Our study contributes to a better understanding of the biodiversity and phylogenetic relationships of bacteria associated with soil-borne nematodes.

Se desarrolló un experimento con semillas de accesiones de Leucaena spp. cosechadas en suelo ácido y almacenadas bajo condiciones ambientales, para determinar el período e intensidad de la dormancia y su ruptura. Para ello se empleó un diseño de clasificación simple y cuatro réplicas, con los siguientes tratamientos: 1) semilla sin tratar (control); 2) corte de cubierta; y 3) agua a 80°C durante 2 minutos. En cada una de las accesiones hubo diferencias significativas entre los tratamientos aplicados y los mayores valores de germinación se encontraron con el corte de cubierta. Todas las accesiones mostraron estado dormático (entre 10 y 98%), el cual se apreció en la germinación del control y en la viabilidad con el corte de cubierta. Los mayores valores de dormancia en las semillas cosechadas en el 2006 se detectaron en L. macrophylla CIAT 17233, L. macrophylla CIAT 17231, L. diversifolia CIAT 17270 y L. leucocephala IH-1140, cuya dureza fue de 98,0; 97,0; 80,0 y 74,7%, respectivamente; en las cosechadas en el 2003 y 2004, los porcentajes de dureza fueron de 89,0; 69,0 y 60,0% para L. lanceolata CIAT 17252, L. macrophylla CIAT 17238 y L. leucocephala cv. K-67, respectivamente. Se concluye que las semillas de las accesiones presentaron dormancia poscosecha, que varió entre 10 y 98%. Además la escarificación térmica provocó su ruptura, por lo que se recomienda aplicar este procedimiento antes de la siembra a las semillas de Leucaena spp. que se cosechen en suelo ácido de Cascajal.A trial was conducted with seeds of Leucaena spp accessions harvested on acid soil and stored under ambient conditions, in order to determine the period and intensity of dormancy and its breaking. For that purpose a simple classification design and four replications were used, with the following treatments: 1) untreated seed (control); 2) coat cut; and 3) water at 80ºC for 2 minutes. In each one of the accessions there were significant differences among the applied treatments and the highest germination values were found with the seed coat cut. All the accessions showed dormant state (between 10 and 98%), which was observed in the germination of the control and the viability with the seed coat cut. The highest dormancy values in the seeds harvested in 2006 were detected in L. macrophylla CIAT 17233, L. macrophylla CIAT 17231, L. diversifolia CIAT 17270 and L. leucocephala IH-1140, which hardness was 98,0; 97,0; 80,0 and 74,7%, respectively; in the seeds harvested in 2003 and 2004, the hardness percentages were 89,0; 69,0 and 60,0% for L. lanceolata CIAT 17252, L. macrophylla CIAT 17238 and L. leucocephala cv. K-67, respectively. The seeds of the accessions were concluded to show postharvest dormancy, which varied between 10 and 98%. In addition, thermal scarification caused dormancy breaking, for which the application of this procedure before planting to Leucaena spp seeds harvested on acid soil in Cascajal, is recommended.

Con el objetivo de caracterizar la composición bromatológica de diferentes accesiones e híbridos apomícticos de Brachiaria spp., en condiciones agroecológicas de Barrancabermeja, Santander, Colombia, se evaluaron 24 accesiones de este género. Se utilizó un diseño experimental completamente aleatorizado, en 72 parcelas de 21 m2 cada una y tres réplicas (parcelas) para cada tratamiento. Se determinó la MS, la PB, los contenidos de grasa, cenizas y de fibra ácido detergente (FAD). Los contenidos de materia seca oscilaron en un rango de 23,4 a 25,7%; mientras que los de proteína estuvieron entre 5,8 y 7,5%, con los valores más bajos para B. humidicola CIAT-26159 y los más elevados en B. brizantha CIAT-6387y CIAT-26124. A pesar de que no se hallaron variaciones importantes en la composición bromatológica de las accesiones, las especies más promisorias en las condiciones agroecológicas evaluadas fueron: B. híbrido 1873, B. brizantha 16315 y B. brizantha 16488With the objective of characterizing the bromatological composition of different accessions and apomictic hybrids of Brachiaria spp., under the agroecological conditions of Barrancabermeja, Santander, Colombia, 24 accessions of this genus were evaluated. A completely randomized experimental design was used, with 72 plots of 21 m2 each and three replications (plots) per treatment. The DM, CP, contents of fat, ash and acid detergent fiber (ADF) were determined. The dry matter contents oscillated from 23,4 to 25,7%, while those of crude protein were between 5,8 and 7,5%; with the lowest values for B. humidicola CIAT-26159 and the highest in B. brizantha CIAT-6387 and CIAT-26124. Although no important variations were found in the bromatological composition of the accessions, the most promising species under the evaluated agroecological conditions were: B. híbrido 1873, B. brizantha 16315 and B. brizantha 16488.

Con el fin de estudiar los cambios en la diversidad y cuantía de la flora en un pastizal manejado de forma racional y disturbado por la quema, se determinó la composición botánica durante cuatro años y medio, utilizando un marco cuadrado en 20 puntos de cada cuartón. Al concluir el período experimental existió una fuerte hegemonía de las gramíneas y las leguminosas perennes con relación a las especies de otras familias con igual ciclo, tanto en número (22 vs 1) como en área cubierta (92,7 vs 0,004%). Un patrón similar se detectó en las especies anuales, independientemente de la familia. El área cubierta por las gramíneas se incrementó después de la quema y en las leguminosas tendió a disminuir, así como su número (7 vs 4). Panicum maximum cv. Likoni fue la especie predominante, al aumentar de 27,3 a 68,0%; Brachiaria decumbens se incrementó ligeramente (1,0 a 4,6%); mientras que Andropogon gayanus disminuyó (21,4 a 6,0%). Especies adventicias como Dichanthium annulatum, Dichanthium aristatum e Indigofera mucronata incrementaron o mantuvieron poblaciones fluctuantes; otras como Dichanthium caricosum y Centrosema molle disminuyeron; mientras que Acacia farnesiana y Alysicarpus vaginalis tendieron a desaparecer. Se concluye que en estas condiciones se creó una cubierta muy diferente a la que se produjo con un manejo racional intensivo aplicado con anterioridad y se corroboró la importancia del índice de composición de especies para explicar las variaciones que se producen en pastoreo.With the objective of studying the changes in the diversity and quantity of the flora in a pastureland rationally managed and disturbed by burning, the botanical composition was determined during four years and a half, using a square frame in 20 spots of each paddock. By the end of the experimental period there was a strong hegemony of grasses and perennial legumes with regards to the species from other families with equal cycle, in number (22 vs 1) as well as in covered area (92,7 vs 0,004%). A similar pattern was detected in annual species, independently from the family. The area covered by the grasses increased after burning and in legumes it tended to decrease, as well as their number (7 vs 4). Panicum maximum cv. Likoni was the prevailing species, increasing form 27,3 to 68,0%; Brachiaria decumbens increased slightly (1,0 to 4,6%); while Andropogon gayanus decreased (21,4 to 6,0%). Adventitious species such as Dichanthium annulatum, Dichanthium aristatum and Indigofera mucronata increased or maintained fluctuating populations; others like Dichanthium caricosum and Centrosema molle decreased; while Acacia farnesiana and Alysicarpus vaginalis tended to disappear. It is concluded that under these conditions a cover was created very different from the one produced with a previously applied intensive rational management and the importance of the species composition index to explain the variations produced in grazing was corroborated.

El establecimiento de leguminosas herbáceas dentro de las áreas de frutales precisa de estudios que demuestren la compatibilidad de estas asociaciones, con vista a mejorar la producción en estos agroecosistemas. El objetivo del presente trabajo fue seleccionar la especie leguminosa más adecuada para emplearla como cobertura viva en plantaciones de naranja Valencia late, sobre la base de su caracterización morfoagronómica. El estudio se realizó en áreas de la Empresa de Cítricos Ciego de Ávila. Para ello se establecieron parcelas de 3 m2, sobre un suelo Ferralítico Rojo compactado, donde no se había aplicado fertilizantes ni herbicidas. Se utilizaron 14 tratamientos y se midieron los siguientes indicadores: emergencia (a los 7, 14, 21, 28 y 35 días después de la siembra en cada parcela), altura (cm), cobertura foliar (%) y producción de semillas (t ha-1). De acuerdo con los resultados, Teramnus labialis fue la especie más adecuada para usarla como cobertura viva en plantaciones citrícolas, en correspondencia con el porcentaje de emergencia, el área cubierta, la altura estacional y la producción de semilla alcanzada durante el proceso de evaluación, por lo que se recomienda su utilización en los ecosistemas citrícolas de naranja V. late de Ciego de Ávila.The establishment of herbaceous legumes within fruit tree areas requires studies that prove the compatibility of these associations, aiming at improving production in these agroecosystems. The objective of this work was to select the most adequate legume species to be used as live cover in Valencia late orange plantations, based on their morphoagronomic characterization. The study was conducted in areas of the Ciego de Ávila Citrus Fruit Enterprise. For such purpose 3 m2 plots were established on a compacted Ferralitic Red soil, where neither fertilizers nor herbicides had been applied. Fourteen treatments were used and the following indicators were measured: emergence (7, 14, 21, 28 and 35 days after planting in each plot), height (cm), leaf cover (%) and seed production (t ha-1). According to the results, Teramnus labialis was the most adequate species to be used as live cover in citrus fruit plantations, in correspondence with the emergence percentage, the area covered, seasonal height and seed production reached during the evaluation process, for which its use is recommended in citrus fruit systems of V. late orange in Ciego de Ávila.

Se realizó un ensayo con el objetivo de evaluar tres procedencias de Jatropha curcas, en un suelo Ferralítico Rojo lixiviado de la EEPF ¨Indio Hatuey¨, en las fases de vivero, establecimiento y momento de cosecha. Todas las procedencias necesitaron entre 70 y 90 días para alcanzar su máximo de emergencia. La de Cabo Verde (denominada Africana) fue la primera en germinar (11,5-24,6% entre los primeros cinco y 25 días) y las dos restantes germinaron a los 35 días. A los 160 días después de plantadas, la Africana alcanzó la fenofase de semilla verde; mientras que las dos restantes se encontraban en abotonamiento. La Africana también fue estadísticamente superior en términos de número de hojas, grosor del tallo y altura de las plántulas. No existieron diferencias en la producción de frutos con tres semillas, indicador en el que todas alcanzaron más del 70%. A los 240 días (cosecha) se detectó una alta disminución en el número de hojas, pero el menor porcentaje se constató en la Africana (69% con relación al total). El peso de la semilla cosechada en la Africana fue 7,1 veces superior a la procedencia de Las Tunas (medianamente ramificada) y 22,4 veces superior a la de Sancti Spiritus (menos ramificada). De acuerdo con los resultados, se destacó por su comportamiento la Africana. Asimismo, se considera importante la introducción de un mayor número de accesiones, así como la realización de estudios sobre la calidad de la semilla.A trial was conducted with the objective of evaluating three provenances of Jatropha curcas on a lixiviated Ferralitic Red soil of the EEPF ¨Indio Hatuey¨, at the nursery, establishment and harvest stages. All the provenances needed between 70 and 90 days to reach their emergence maximum level. The plants from Cape Verde (called African) were the first to germinate (11,5-24,6% between the first five and 25 days) and the other two germinated 35 days after planting. One hundred and sixty days after planting, the African one reached the green seed phenophase; while the other two were budding. The African provenance was also statistically higher in terms of leaf number, stem diameter and seedling height. There were no differences in the production of fruits with three seeds, indicators in which they all reached more than 70%. Two hundred and forty days after planting (harvest) a high decrease in the leaf number was detected, but the lowest percentage was observed in the African provenance (69% with regards to the total). The weight of the seed harvested in the African provenance was 7,1 times higher than the Las Tunas provenance (moderately ramified) and 22,4 times higher than the Sancti Spiritus provenance (less ramified). According to the results, the African plants stood out for their performance. Likewise, the introduction of a higher number of accessions is considered important, as well as the completion of studies on seed quality.

Este trabajo se realizó en la EEPF ¨Cascajal¨sobre un suelo Alítico, con el objetivo de determinar la composición botánica de accesiones del género Brachiaria, después de haber completado la fase de evaluación agronómica. Se estudiaron dos colecciones, una de B. brizantha con 36 accesiones y otra formada por 30 accesiones de Brachiaria spp.; las especies y la cantidad de accesiones fueron: B. decumbens (14), B. dictyoneura (8), B. ruziziensis (3), B. humidicola (3), B. purpurascens (1) y B. arrecta (1). Se utilizó el método del metro cuadrado dividido en decímetros y la observación se hizo al final del período de evaluación. Se concluye que las colecciones de B. brizantha y Brachiaria spp. mostraron un buen cubrimiento de las parcelas, lo que representó un 85,9 y 80,0%, respectivamente, del total de las accesiones evaluadas.This work was carried out at the EEPF ¨Cascajal¨, on an Alitic soil, with the objective of determining the botanical composition of accessions of the Brachiaria genus, after completing the stage of agronomic evaluation. Two collections were studied, one of B. brizantha with 36 accessions and the other made up by 30 accessions of Brachiaria spp.; the species and quantity of accessions were: B. decumbens (14), B. dictyoneura (8), B. ruziziensis (3), B. humidicola (3), B. purpurascens (1) and B. arrecta (1). The method of the square meter divided into decimeters was used and the observation was carried out at the end of the evaluation period. The collections of B. brizantha and Brachiaria spp. were concluded to show good covering of the plots, which represented 85,9 and 80,0%, respectively, of the total of the evaluated accessions.

La presente investigación se desarrolló con el objetivo de evaluar el comportamiento agronómico (a partir del segundo año de producción) de una colección de accesiones de Brachiaria spp. para seleccionar aquellas de mejor adaptación a las condiciones agroecológicas de la región Santandereana de Barrancabermeja. Los cor­tes se realizaron cada 42 días, después de concluir el primer año de evaluación. Se determinó la altura de la planta, la producción de forraje, el porcentaje de hojas y la incidencia de enfermedades. Según el ACP los indicadores más influyentes fueron: la producción de forraje y el porcentaje de hojas; no se presentaron afectaciones por plagas y enfermedades. Se destacaron, por presentar valores superiores a la media poblacional, las accesiones: B. dictyoneura (CIAT-6133), B. brizantha (CIAT-16488, CIAT-16212, CIAT-16121 y CIAT­16322) y B. decumbens (CIAT-606); mientras que las de menor adaptación y productividad fueron: B. ruziziensis CIAT-26180; B. brizantha CIAT-16315, CIAT-16327 y CIAT-6387; B. decumbens CIAT-16497; y B. humidicola CIAT-26159, CIAT-16871, CIAT-16867 y CIAT-26427. Se recomienda difundir, de manera progresiva, las accesiones destacadas para su uso en los ecosistemas ganaderos.This research was carried out with the objective of evaluating the agronomic performance (from the second year of production) of a collection of Brachiaria spp. accessions, in order to select those of better adaptation to the agroecological conditions of the Santander region of Barrancabermeja. The cuttings were performed every 42 days, after concluding the first year of evaluation. Plant height, forage production, leaf percentage and disease incidence were determined. According to the MCA the most influencing indicators were: forage production and leaf percentage; no affectations by pests and diseases were present. The accessions B. dictyoneura (CIAT-6133), B. brizantha (CIAT-16488, CIAT-16212, CIAT-16121 and CIAT-16322) and B. decumbens (CIAT-606) stood out for presenting values higher than the population mean; while those of lower adaptation and productivity were: B. ruziziensis CIAT-26180; B. brizantha CIAT-16315, CIAT-16327 and CIAT-6387; B. decumbens CIAT-16497 and B. humidicola CIAT-26159, CIAT-16871, CIAT-16867 and CIAT-26427. To disseminate, progressively, the outstanding accessions for their use in livestock production ecosystems, is recommended.

Se evaluaron 24 accesiones de Brachiaria spp. en 72 parcelas de 21 m², con el objetivo de seleccionar las de mejor respuesta en las condiciones de suelos ácidos y de baja fertilidad de la región de Barrancabermeja. La germinación se realizó en vivero, con semillas sexuales. A los 138 días de sembradas y después de un corte de homogenización comenzó el primer año de evaluación, con cortes cada 42 días hasta los 390 días. Se determi­nó el porcentaje de emergencia y el de cobertura, la altura de la planta, la producción de forraje, el porcentaje de hojas y la incidencia de plagas y enfermedades. Los análisis se realizaron por el paquete estadístico SPSS 10.0. Según el ACP los indicadores más variables fueron: la altura, la producción de forraje, el porcentaje de hojas, el porcentaje de emergencia, la incidencia de plagas y enfermedades, y el porcentaje de cobertura. Se destacaron las especies B. dictyoneura (CIAT-6133), B. brizantha (CIAT-16488, CIAT-16212, CIAT-26318, CIAT-16121, CIAT-16113 y CIAT-16322), B. decumbens (CIAT-606) y B. humidicola (CIAT-26159).Twenty-four accessions of Brachiaria spp. were evaluated in 72 plots of 21 m², with the objective of selecting those with the best response under the conditions of low fertility acid soils of the Barrancabermeja region. Germination was carried out in nursery with sexual seed. One hundred thirty eight days after sowing and after a homogenization pruning the first year of evaluation started, with cuttings every 42 days until 390 days. The emergence and cover percentage, plant height, forage production, leaf percentage and incidence of pests and diseases were determined. The analyses were performed by means of the statistical pack SPSS 10.0. According to the MCA the most variable indicators were: height, forage production, leaf percentage, emergence percentage, incidence of pests and diseases and cover percentage. The species B. dictyoneura (CIAT-6133), B. brizantha (CIAT-16488, CIAT-16212, CIAT-26318, CIAT-16121, CIAT-16113 and CIAT-16322), B. decumbens (CIAT­606) and B. humidicola (CIAT-26159), stood out.

El objetivo de este trabajo fue caracterizar una colección de Teramnus spp. formada por 48 accesiones procedentes del CIAT, Colombia; para ello se tomaron en consideración descriptores internacionales para leguminosas forrajeras y otros descriptores de interés (32 en total, cuantitativos y cualitativos). La semilla de cada accesión se sembró en 12 nichos, en parcelas sencillas de 3 x 1 m y se les colocó un tutor que les permitiera el máximo crecimiento y desarrollo. Las mediciones y observaciones se realizaron cuando las plantas alcanzaron la fenofase de semilla verde a madura. La aplicación del Análisis de Componentes Principales permitió comprobar la existencia de una variabilidad relativamente alta para todos los caracteres, ya que el acumulado solo alcanzó el 67,7% en las ocho primeras componentes; se destacaron los descriptores cuantitativos, con un 51,8% en las primeras cinco componentes. La agrupación de las accesiones sobre la base de las dimensiones foliares y el número de semillas, a través de un Análisis de Conglomerados, permitió la formación de cinco grupos contrastantes; se distinguieron dos accesiones de T. labialis (CIAT-927 y CIAT-9007), en las que se maximizaron estos caracteres en relación con las restantes de esta especie; mientras que el 62,0% de esta colección estuvo representada por fenotipos con hojas cortas, foliolos cortos y angostos, peciolos cortos y un número de semillas por legumbre que no rebasó una media superior a 8. Se concluye que la caracterización permitió comprobar la relativa variabilidad de sus componentes, aun cuando esta se amplía con relación al germoplasma existente en el país para especies de este género y, por otra parte, lo incrementa considerablemente. Se sugiere la evaluación de las potencialidades agroproductivas de interés, con fines selectivos.The objective of this work was to characterize a collection of Teramnus spp. formed by 50 accessions from the CIAT, Colombia. For that international descriptors for forage legumes and other descriptors of interest (32 in total, quantitative and qualitative) were taken into consideration. The seed of each accession, was planted in 12 niches in simple 3 x 1 m plots and a stake was placed to allow them their highest growth and development. The measurements and observations were carried out when the plants reached the phenohase of green to ripe seed. The application of the Main Component Analysis allowed to prove the existence of a relatively high variability for all the characters, because the total only reached 67,7% in the first eight components; the quantitative descriptors stood out, with 51,8% in the first five components. The grouping of the accessions based on the foliar dimensions and number of seeds, through a Cluster Analysis, allowed the formation of five contrasting groups; two accessions of T. labialis (CIAT-927 and CIAT-9007) were distinguished, in which these characters were maximized with regards to the others of these species; while 62,0% of this collection was represented by phenotypes with short leaves, short and narrow folioles, short petioles and a number of seeds per pod that did not exceed a mean higher than 8. It is concluded that the characterization allowed to prove the relative variability of its components, although it is widened with regards to the existing germplasm in the country for species of this genus and, on the other hand, it increases the germplasm considerably. The evaluation of the agroproductive potentials of interest, with selective objectives, is recommended.

Se realizó una labor de prospección y colecta en la zona oriental del país con el objetivo de colectar germoplasma de leguminosas herbáceas, arbustivas y arbóreas multipropósito para ser utilizadas en el sector ganadero. El trayecto incluyó la costa norte y sur de la provincia de Guantánamo, la costa norte y centro de la provincia Holguín, así como la parte centro-este de la provincia Granma. Se utilizó un sistema de muestreo individual en pequeñas poblaciones, con repetitividad de especies en diferentes sitios, y en ocasiones se muestreó aleatoriamente en poblaciones abundantes. La información se recogió a través de los descriptores relacionados con la localización, el hábitat natural, la vegetación, el suelo y los daños motivados por insectos y enfermedades, entre otros. Se colectaron 95 accesiones pertenecientes a 24 especies, entre las que primaron las de tipo herbáceo (10 géneros). Se encontraron especies utilizadas con diversos propósitos (alimento animal, cobertura, abono verde, cercas vivas, etc.), tanto herbáceas como arbustivas y arbóreas. Se recomienda beneficiar las muestras obtenidas; proceder a su rápida reproducción, caracterización morfobotánica y evaluación agronómica (fase I); utilizar este material para diversos fines, entre ellos la conservación y el intercambio; así como continuar la colecta en otras zonas del país.A prospecting and collection work was carried out in the eastern zone of the country with the objective of collecting germplasm of herbaceous, shrubby and tree multipurpose legumes to be used in the livestock production sector. The trip included the northern and southern coast of the Guantanamo province, the northern and central coast of the Holguín province, as well as the central-eastern part of the Granma province. An individual sampling system was used in small populations, with repetitiveness of species in different sites, and sometimes random sampling was performed in abundant populations. The information was gathered through the descriptors related to location, natural habitat, vegetation, soil and damage caused by insects and diseases, etc. Ninety-five accessions belonging to 24 species were collected, among which stood out those of herbaceous type (10 genera). Herbaceous as well as shrubby and tree species used with different purposes were found (animal feed, cover, green manure, living fences, etc.). It is recommended to clean the samples obtained; proceed to their fast reproduction, morphobotanical characterization and agronomic evaluation (stage I); use this material for different purposes, among them conservation and exchange; as well as to continue the collection in other zones of the country.

Los sistemas agroforestales representan importantes sumideros de carbono; sin embargo, en Cuba no han sido considerados en este sentido debido fundamentalmente a la ausencia de información cuantificada sobre su potencialidad de almacenamiento y fijación. La presente investigación muestra los resultados comparativos de una finca con un pastizal natural y otra convertida en un sistema agroforestal, con 11 años de explotación. El carbono almacenado por el sistema silvopastoril fue mayor que el secuestrado en el sistema de pasto natural. El carbono forestal y el retenido en los pastos y en el suelo alcanzó valores de 64, 38 y 24 t/ha, respectivamente. El sistema silvopatoril secuestró126 t de carbono, a diferencia del sistema de pasto natural que solo alcanzó 32 t/ha en el año de evaluación. El sistema agroforestal superó sustancialmente al sistema de pasto natural, por su alta contribución ambiental y económica, cuyo valor se aproximó a los 1 300 dólares (USD) por año. Esta valoración económica es un elemento fundamental para lograr una utilización sostenible del ecosistema y, aunque no constituye el instrumento a tener presente para todas las decisiones, representa uno de los aspectos que intervienen en el proceso decisorio, junto con otras importantes consideraciones políticas, sociales y culturales. Los resultados confirman que los sistemas agroforestales son una alternativa para el desarrollo sostenible de los sistemas en el sector agropecuario.Agroforestry systems represent important carbon sinks; nevertheless, in Cuba they have not been considered in that sense due, mainly, to the absence of quantified information about their storage and fixation potential. This study shows the comparative results of a farm with a natural pasture and another turned into an agroforestry system with 11 years of exploitation. The carbon stored by the silvopastoral system was higher than that sequestered in the system of natural pasture. The forest carbon and the one retained in the pastures and in the soil reached values of 64; 38 and 24 t/ha, respectively. The silvopastoral system sequestered 126 t of carbon unlike the system of natural pasture, which only reached 32 t/ha in the year of evaluation. The agroforestry system substantially exceeded the system of natural pasture for its high environmental and economic contribution; its economic value is about 1 300 USD per year. This economic assessment is an essential element to achieve a sustainable utilization of the ecosystem and, although it does not constitute the instrument to be taken into consideration for all decisions, it represents one of the aspects involved in the decision-making process, together with other important political, social and cultural considerations. The results confirm that silvopastoral systems are an alternative for the sustainable development of the livestock production sector.

Con el objetivo de determinar el potencial de rendimiento de la morera variedad Tigreada, se estudiaron dos alturas (50 y 100 cm) y dos frecuencias de corte (45 y 90 días), en un diseño totalmente aleatorizado, durante dos años consecutivos. En cada tratamiento se utilizaron 20 plantas para evaluar las variables agronómicas: rendimiento de materia seca de la biomasa total (RMSBT), rendimiento de materia seca de la biomasa comestible (RMSBC), rendimiento de materia seca de las hojas (RMSH), rendimiento de materia seca de los tallos tiernos (RMSTT) y rendimiento de materia seca de los tallos leñosos (RMSTL), en los períodos lluvioso (PLL) y poco lluvioso (PPLL). Para algunas de las variables agronómicas se encontró interacción significativa (PWith the objective of determining the yield potential of mulberry variety Tigreada, two cutting heights (50 and 100) and frequencies (45 and 90 days) were studied, in a completely randomized design, for two consecutive years. Twenty plants were used in each treatment to evaluate the agronomic variables: dry matter yield of the total biomass (DMYBT), dry matter yield of the edible biomass (DMYEB), dry matter yield of the leaves (DMYL), dry matter yield of the fresh stems (DMYFS) and dry matter yield of the ligneous stems (DMYLS), in the rainy (RS) and dry seasons (DS). For some of the agronomic variables significant interaction (P

En un suelo ácido de baja fertilidad, se estudió una colección de 36 accesiones de la especie B. brizantha, con el objetivo de seleccionar las accesiones de mejor comportamiento general, sobre la base de algunos indicadores cuantitativos, durante el período lluvioso. La plantación se realizó en parcelas de 3 x 1 m, sin réplicas. Los indicadores estudiados fueron: la altura de la planta, la hojosidad, el vigor, la cobertura, las afectaciones producidas por plagas y enfermedades, la presencia de clorosis y el rendimiento de biomasa. Para la interpretación de los resultados se utilizó el análisis de componentes principales (ACP) y análisis de conglomerados. Mediante el primero se detectó una alta variabilidad para las dos primeras componentes (77,19%); mientras que el segundo permitió identificar seis grupos diferentes. Se concluye que las accesiones, en general, mostraron un adecuado desarrollo en las condiciones edafoclimáticas existentes y algunas sobresalieron por su aceptable rendimiento y adaptación a este ambiente. Del total de la colección, las más sobresalientes para estos suelos fueron: B. brizantha CIAT-26646, CIAT-16317, CIAT-26032, CIAT-16809, Nº 1, CIAT-16473, CIAT-16154, CIAT-16334, CIAT-16335, CIAT-16197, CIAT-16132, CIAT-16322, CIAT-16485, CIAT-16303, CIAT-16448, CIAT-16311, CIAT-16332, CIAT-16819, CIAT-16110 y CIAT-16482. Se recomienda estudiar el material seleccionado en condiciones de pastoreo, con el fin de determinar las variedades precomerciales en este ambienteIn a low fertility acid soil, a collection of 36 accessions of the B. brizantha species was studied, with the objective of selecting the accessions of better general performance, based on some quantitative indicators, during the rainy season. The plantation was carried out in 3 x 1 m plots, without replications. The indicators studied were: plant height, leafiness, vigor, cover, affectations caused by pests and diseases, presence of chlorosis and biomass yield. For the interpretation of the results the main component analysis (MCA) and cluster analysis were used. By means of the former a high variability was detected for the first two components (77,19%); while the latter allowed to identify six different groups. The accessions, in general, were concluded to show an adequate development under the existing edaphoclimatic conditions and some of them stood out for their acceptable yield and adaptation to that environment. From the collection total, the most outstanding for these soils were: B. brizantha CIAT-26646, CIAT- 16317, CIAT-26032, CIAT-16809, No 1, CIAT-16473, CIAT-16154, CIAT-16334, CIAT-16335, CIAT-16197, CIAT-16132, CIAT-16322, CIAT-16485, CIAT-16303, CIAT-16448, CIAT-16311, CIAT-16332, CIAT-16819, CIAT- 16110 and CIAT-16482. To study the material selected under grazing conditions is recommended, with the objective of determining the pre-commercial varieties in this environment