ABSTRACT Agonoscena pistaciae (Hemiptera: Psyllidae) is a significant pest in pistachio (Pistacia vera L.) orchards in Türkiye. This study aimed to evaluate the effectiveness of yellow sticky traps as an alternative method for controlling A. pistaciae populations in pistachio orchards. Conducted in late September and early October of 2021 and 2022, during peak pest activity, the experiment was carried out in Siirt, with three replicates following a randomized block design. Five traps were hung on all sides of each tree for sampling. Repeated measures ANOVA (repeated measures; general linear model) was used to observe changes over time. The results indicated that yellow sticky traps were highly effective in mass trapping adults, capturing an average maximum of 12 332.67 adults per trap. A significant decrease in the number of nymphs and eggs on the leaves was observed in the yellow sticky trap-treated trees compared to the control plots by mid-October (P < 0.05). Specifically, the average number of nymphs per composite leaf dropped from 24.95 to 11.23 in 2021, and from 145.18 to 27.29 in 2022. Similarly, the average number of eggs per composite leaf decreased from 61.18 to 2.29 in 2021, and from 73.56 to 3.64 in 2022. These findings suggest that yellow sticky traps can significantly reduce psyllid populations in pistachio orchards over the long term and can be an effective control method when used early in the vegetative period for low- to medium-sized psyllid populations.

Abstract Climate change and the lack of fuel management in oak forests promote favorable conditions for the occurrence of forest fires. The objective of the present research was to know the relationship of dasometric variables, terrain slope (Pe), depth of leaf litter (Ph) and depth of mulch (Pm) on the fuel load in oak forests in the Mountain region of Guerrero. The dasometric variables mean diameter (Dm), mean height (Am), number of trees ha-1 (Na) and basal área ha-1 (Ab) were evaluated according to the sampling design of the 2015 National Forest and Soil Inventory; At each sampling site, three planar intersection lines were established for sampling woody material (Ml), leaf litter (Ho) and mulch (Ma) were collected in 0.09 m2. The total fuel load ranged from 23.2 to 46.5 t ha-1 (p < 0.05), the Ma presented the highest load with 43%, followed by woody material (Ml) and leaf litter (Ho) with 31 and 26%. The total charge (Ct) showed a relationship with Ma, Ho and Ml (r = 0.81 to 0.41), Ho with Ph and Pe (r = 0.71 and -0.72). The c1h showed a relationship with Na, Ma, Pe and Dm (r = 0.72 to -0.41), the c10h showed a correlation with Ab, Pe and Na (r = 0.51 to 0.42). The dasometric variables only explain the fuel load with a diameter less than or equal to 2.5 cm.

Resumen El cambio climático y la falta de manejo a los combustibles en los bosques de encino propicia condiciones favorables para la ocurrencia de incendios forestales. El objetivo de la presente investigación fue conocer la relación de variables dasométricas, pendiente del terreno (Pe), profundidad de la hojarasca (Ph) y profundidad del mantillo (Pm) sobre la carga de combustible en bosques de encino en la región Montaña de Guerrero. Las variables dasométricas diámetro medio (Dm), altura media (Am), número de árboles ha-1 (Na) y Área basal ha-1 (Ab) se evaluaron de acuerdo al diseño de muestreo del Inventario Nacional Forestal y de Suelos 2015; en cada sitio de muestreo se establecieron tres líneas de intersección planar para el muestreo de material leñoso (Ml), se recogió la hojarasca (Ho) y mantillo (Ma) en 0.09 m2. La carga total de combustibles osciló de 23.2 a 46.5 t ha-1 (p < 0.05), el Ma presentó mayor carga con el 43 %, seguido el material leñoso (Ml) y hojarasca (Ho) con el 31 y 26 %. La carga total (Ct) mostró relación con el Ma, Ho y Ml (r = 0.81 a 0.41), la Ho con Ph y Pe (r = 0.71 y -0.72). El c1h mostró relación con el Na, Ma, Pe y Dm (r = 0.72 a -0.41), el c10h evidenció correlación con el Ab, Pe y Na (r = 0.51 a 0.42). Las variables dasométricas solo explican la carga de combustible con diámetro menor o igual a 2.5 cm.

Abstract Background: Agroforestry systems integrate agricultural, forestry and cultural diversity and have been little studied in coastal regions of Mexico. The SA managed by mixtecs and afro-mexicans are unknown. Questions: Which agroforestry systems are found in Mixtec and Afro-Mexican communities? Which are the forms of management, agricultural and agroforestry practices and useful species in agroforestry systems? Studied species: Various. Study site and dates: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. October 2021 to October 2022. Methods: Sixty semi-structured interviews were conducted with local specialists in three Mixtec and three Afro-Mexican communities. Questions were asked about traditional agroforestry systems, agricultural, agroforestry and management practices, and useful species. Tours and collections of herbarium specimens were carried out. Each system was described, management and agroforestry practices were categorized; and the number of useful species by category of use and cultural group was recorded. Results: Six agroforestry systems were recorded and described: milpa, pastures, plots, acahuales; piñal and coconut. Agricultural practices in Mixtec communities are carried out with basic tools and inputs and the production is for self-consumption and local sale, while in Afro-Mexican communities they are technical, and their destination is regional sale. The most common agroforestry practices were the boundaries and isolated trees. Conclusions: The cultural groups share agroforestry systems, forms of management, and number of useful species is similar, but they differ in agricultural practices. In the agroforestry systems, edible and timber species (firewood, poles, fences, construction) are mainly conserved.

Resumen Antecedentes: Los sistemas agrosilvícolas (SA) integran diversidad agrícola, forestal y cultural. En regiones costeras de México han sido poco estudiados, particularmente los manejados por mixtecos y afromexicanos de la costa de Oaxaca. Preguntas: ¿Qué SA se encuentran en comunidades mixtecas y afromexicanas?, ¿Cuáles son las especies útiles, formas de manejo, prácticas agrícolas y agroforestales de los SA? Especies de estudio: Diversas. Sitio y años de estudio: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. Octubre 2021 a octubre 2022. Métodos: Se realizaron 60 entrevistas semiestructuradas a especialistas locales en tres comunidades mixtecas y tres afromexicanas. Se preguntó acerca de especies útiles, sistemas agrosilvícolas, prácticas agrícolas, agroforestales y de manejo. Se realizaron recorridos y colectas de ejemplares de herbario. Se describió cada sistema por sus prácticas agroforestales y de manejo. Se registró el número de especies útiles por categoría de uso y grupo cultural. Resultados: Se documentaron y describieron seis SA: milpa, potreros, solares, acahuales, piñal y cocotal. Las prácticas agrícolas en comunidades mixtecas se realizan con herramientas e insumos básicos y la producción tiene un fin de autoconsumo y venta local, mientras que en comunidades afromexicanas son tecnificadas y su destino es la venta regional. Linderos y árboles aislados fueron las prácticas agroforestales más comunes. Conclusiones: Mixtecos y Afromexicanos comparten SA, formas de manejo y prácticas agroforestales, difieren en las prácticas agrícolas. En los SA se conservan principalmente especies comestibles y maderables. El número de especies útiles es similar en comunidades mixtecas y afromexicanas.

Resumen Las poblaciones de Pinus montezumae del centro de México son esenciales por su contribución en servicios ambientales a más de 25 millones de personas de esta zona. Estos bosques han sido amenazados por el cambio de uso de suelo y la fragmentación, lo que reduce su regeneración. El objetivo del presente estudio fue determinar la germinación de semillas y algunas características morfológicas de plántulas de P. montezumae de ocho poblaciones del centro de México, así como analizar la influencia de la densidad de rodales y variables climáticas y edáficas sobre la calidad de semillas. Se utilizaron semillas de 10 árboles por población. Se evaluaron varios parámetros germinativos y características morfológicas de plántulas a los 40 días después de emergencia. Se utilizó un modelo lineal mixto generalizado para evaluar la significancia del factor población en cada característica y se realizaron análisis de correlación de Pearson con variables edáficas, ambientales y de densidad. Hubo diferencias estadísticas (P ≤ 0.05) en las variables evaluadas. La germinación media fue 84 %, con variación de 80.7 a 87 % entre poblaciones. Las plántulas presentaron, en promedio, 6.5 cotiledones (3-10, pero 6-7 más común) con una longitud de 29 mm y un hipocótilo de 16.4 mm. La germinación estuvo relacionada con la precipitación (r = 0.75), y el número y la longitud de cotiledones con la temperatura de los sitios de origen de las poblaciones (r = 0.84, r = 0.87, respectivamente). La materia orgánica mostró correlación negativa con la longitud de cotiledones (r = -0.94). El contenido de fósforo del suelo de origen correlacionó positivamente con la germinación (r = 0.94) y con el número de cotiledones (r = 0.77), mientras que el nitrato lo hizo con la longitud del hipocótilo (r = 0.80). La densidad de árboles no presentó correlación con las variables evaluadas, por lo que el bajo número de árboles no es limitante para la repoblación.

Summary Populations of Pinus montezumae in central Mexico are essential for their contribution in environmental services to more than 25 million people in this area. These forests have been threatened by changes in land use and fragmentation, reducing their regeneration. The objective of this study was to determine seed germination and some morphological characteristics of P. montezumae seedlings of eight populations of central Mexico, as well as analyzing the influence of stand density and climatic and soil variables on seed quality. Seeds from 10 trees per population were used. Several germination parameters and morphological characteristics of seedlings were evaluated at 40 days after emergence. A generalized mixed linear model was used to evaluate the significance of the population factor for each trait and Pearson correlation analyses were performed with soil, environmental and density variables. There were statistical differences (P ≤ 0.05) in the variables evaluated. The average germination was 84 %, with variation from 80.7 to 87 % between populations. Seedlings showed, on average, 6.5 cotyledons (310, but 6-7 more common) with a length of 29 mm and a hypocotyl of 16.4 mm. Germination was related to precipitation (r = 0.75) and the number and length of cotyledons to the temperature of the populations site of origin (r = 0.84, r = 0.87, respectively). Organic matter showed negative correlation with cotyledon length (r = -0.94). Phosphorus content in the soil of origin positively correlated with germination (r = 0.94) and the number of cotyledons (r = 0.77), while nitrate correlated with hypocotyl length (r = 0.80). The density of trees did not correlate with the variables evaluated, so the low number of trees is not limiting for repopulation.

Resumen La diversidad genética es importante para la adaptación de una especie a los cambios ambientales, por lo que el conocimiento del nivel y distribución de la diversidad es útil para elaborar estrategias de conservación y manejo de una especie; sin embargo, la información sobre diversidad genética es escasa para especies arbóreas que habitan en el bosque tropical caducifolio, como es el caso de lináloe [Bursera linanoe (La Llave) Rzed., Calderón & Medina], una especie que crece en dos subprovincias bióticas en el bosque tropical seco de los estados de Guerrero, Morelos, Puebla y Oaxaca en México. Por lo anterior, el objetivo del presente estudio fue estimar la diversidad y estructura genética de Bursera linanoe en poblaciones naturales en dos subprovincias bióticas. En 2019 se recolectó follaje de 92 árboles de lináloe en cuatro poblaciones en las subprovincias bióticas Balsasana y Cañadiana. Posteriormente, el ADN se extrajo del follaje con el protocolo CTAB. Cinco intermicrosatélites (ISSR) se utilizaron, y los fragmentos fueron separados en geles de agarosa. Los siguientes estimadores de diversidad genética se calcularon: porcentaje de loci polimórficos (P), heterocigosidad esperada (He), número efectivo de alelos por locus (Ne) e índice de Shannon (IS); además, se estimó el FST de Wright y se realizó un análisis de varianza molecular (AMOVA). También, la estructura genética se evaluó con el software STRUCTURE. Los valores de los estimadores de la diversidad genética para lináloe fueron: P = 100 %, He = 0.352, Ne = 1.618 e IS = 0.522, el valor de FST fue 0.160. La partición de la diversidad genética fue de 74 % dentro de poblaciones, 21 % entre poblaciones y 5 % entre subprovincias. Cuatro grupos (K) se formaron con los árboles de lináloe de las cuatro poblaciones. El número de migrantes fue 1.3 por generación. Se encontró una diversidad genética alta y una diferenciación alta entre poblaciones de Bursera linanoe.

Summary Genetic diversity is important for the adaptation of a species to environmental changes, thus knowledge of the level and distribution of diversity is useful for developing conservation and management strategies for a species; however, information on genetic diversity is scarce for tree species that habit in the tropical deciduous forest as is case of linaloe [Bursera linanoe (La Llave) Rzed., Calderón & Medina], a species that grows in two biotic subprovinces in the dry tropical forest of the states of Guerrero, Morelos, Puebla and Oaxaca in Mexico. Therefore, the objective of this study was to estimate the genetic diversity and structure of Bursera linanoe in natural populations at two biotic subprovinces. In 2019, foliage was collected from 92 linaloe trees in four populations of the biotic subprovinces Balsasana and Cañadiana. Subsequently, the DNA was extracted from the foliage with the CTAB protocol. Five inter-microsatellites (ISSR) were used, and the fragments were separated on agarose gels. The following estimators of genetic diversity were calculated: percentage of polymorphic loci (P), expected heterozygosity (He), effective number of alleles per locus (Ne) and Shannon index (SI). In addition, the Wright’s FST was estimated, and an analysis of molecular variance (AMOVA) was performed. Also, the genetic structure was evaluated with the STRUCTURE software. The values of the genetic diversity estimators were P = 100 %, He = 0.352, Ne = 1.618 and SI = 0.522, the FST value was 0.160. The partition of genetic diversity was 74 % within populations, 21 % between populations and 5 % between subprovinces. Four groups (K) were formed with the linaloe trees of the four populations. The number of migrants was 1.3 per generation. High genetic diversity and high genetic differentiation between population of Bursera linanoe were found.

Resumen La vegetación es una parte vital de la infraestructura urbana por los servicios ambientales y los beneficios que provee a la población, por lo que es importante conocer su diversidad y estructura. El objetivo del presente trabajo fue evaluar la estructura y composición florística de árboles, palmas y arbustos ubicados en áreas urbanas públicas de la ciudad de Tapachula, en el estado de Chiapas. Se recabó información dasométrica de ocho parques públicos, cinco áreas verdes públicas, cuatro camellones o jardineras y 38 calles, con una superficie total de 27.32 ha. Se registró el diámetro normal (1.30 m de la base del suelo) y la altura total. Se calculó la densidad de especies por área verde. La diversidad fue evaluada mediante los índices de Shannon-Weiner y de Margalef. Taxonómicamente, se identificaron 130 especies, 109 géneros y 44 familias. De los taxa registrados, 65 pertenecen a especies nativas (550 individuos) y 65 a exóticas (1 927 individuos). Ficus microcarpa es el taxón exótico preponderante con un Índice de Valor de Importancia (IVI) de 6.14. De las especies nativas, Roseodendron donnell-smithii destaca como el elemento más representativo (IVI=1.45). El Índice de Shannon-Weiner calculado para diferentes áreas verdes registró 2.7≤H’≤3.3 y el Índice de Margalef 5.2≤D Mg ≤15.2, lo cual evidencia que las calles poseen una gran diversidad de especies.

Abstract Urban vegetation is a vital part of urban infrastructure due to the environmental services it provides and the benefits to the population; therefore, it is important to know its diversity and structure. The objective of this work was to assess the structure and floristic composition of trees, palms and shrubs located in public urban areas of the city of Tapachula, state of Chiapas. Mensuration information was collected from eight public parks; five public green areas, four medians and 38 streets, with a total area of 27.32 ha. Normal diameter (1.30 m base from the ground) and total height were recorded. The density of species per urban green area was calculated. Diversity was evaluated using the Shannon-Weiner and Margalef indexes. Taxonomically, 130 species, 109 genera and 44 families were identified. Of the 130 specific taxa recorded, 65 belong to native species and 65 exotic. The total number of individuals was 1 927 exotic and 550 native. Ficus microcarpa is the predominant exotic with 6.14 Importance Value Index (IVI). Of the native species, Roseodendron donnell-smithii stands out as the most representative (IVI=1.45). The Shannon-Weiner Index calculated for different green areas registered 2.7≤H'≤3.3 and the Margalef Index 5.2≤D Mg ≤15.2, showing that the streets have a great species diversity.

Resumen El Pico de Orizaba es un área natural protegida en la que destacan bosques de Pinus hartwegii sometidos a presiones naturales y antrópicas. El objetivo del presente estudio fue comparar los parámetros dasométricos de ocho rodales con cuatro exposiciones (N, S, E y O) y dos altitudes (3 700 y 3 900 m). Se ubicaron áreas con cobertura representativa y se establecieron tres sitios de dimensiones fijas de 1 000 m2 por cada combinación de exposición-altitud. La obtención de información se complementó con imágenes de un vehículo aéreo no tripulado (VANT). Se obtuvo mayor densidad de arbolado (593 árboles ha-1) en la combinación E-3 700 y la mínima en la zona O-3 900 (113 árboles ha-1). Los extremos de área basal mínima (11.9 m2 ha-1) y máxima (35.2 m2 ha-1) correspondieron a las combinaciones S-3 900 y E-3 700, respectivamente. El área basal y volumen disminuyeron con la altitud. La estructura horizontal mostró mayor número de individuos en categorías diamétricas bajas (10-40 cm) y la estructura vertical en las de 25 a 30 m de altura. La prueba de Kruskal-Wallis evidenció diferencias significativas entre las ocho combinaciones para las variables diámetro (DN), altura total (AT) y volumen (VOL), cuya reducción más notable fue sobre la exposición sur al incrementar la altitud de 3 700 a 3 900 m, lo que indica que la combinación S-3 900 es menos favorable para el crecimiento del arbolado. Las combinaciones exposición-altitud con parámetros dasométricos superiores y más potencial de crecimiento fueron N-3 700, E-3 700, S-3 700 y O-3 900.

Abstract Pico de Orizaba is a natural protected area with Pinus hartwegii forests subjected to natural and anthropogenic pressures. The objective of this study was to compare the mensuation parameters of eight stands with four exposures (N, S, E, and W) at two different altitudes (3 700 and 3 900 m). Areas with representative coverage were located and three sites of fixed dimensions of 1 000 m2 were established for each exposure-altitude combination. The collected information was complemented with images from an unmanned aerial vehicle (UAV). The highest tree density (593 trees ha-1) was obtained in the E-3 700 combination, and the lowest, in the W-3 900 area (113 trees ha-1). The extremes of minimum (11.9 m2 ha-1) and maximum (35.2 m2 ha-1) basimetric area corresponded to combinations S-3 900 and E-3 700, respectively. The basimetric area and volume decreased with the altitude. The horizontal structure showed a greater number of individuals in low diameter categories (10-40 cm), and the vertical structure in the 25 to 30 m height categories. The Kruskal-Wallis test showed significant differences between the eight combinations for the diameter (DN), total height (TA) and volume (VOL) variables. The most notable reduction was on the southern exposure, as the altitude increased from 3 700 to 3 900 m, indicating that the S-3 900 combination is less favorable for tree growth. The exposure-elevation combinations with superior mensuration parameters and more growth potential were N-3 700, E-3 700, S-3 700, and W-3 900.

Resumen Los cafetales (Coffea arabica) de la región de la Montaña de Guerrero mantienen las características de un bosque, además contribuyen a la generación de recursos económicos que ayudan a un gran número de familias a mitigar parte de sus necesidades básicas. El objetivo de este trabajo fue identificar la estructura y los usos de las especies de sombra de los cafetales en dos comunidades Me’phaa de la Montaña de Guerrero. Se muestrearon 12 parcelas en Tres Cruces (TC), Acatepec y La Ciénega (LC), Malinaltepec; se utilizó el método de punto-centro-cuadrado; a los árboles se les midió la distancia, altura, cobertura de copa y diámetro normal. Se estimó la diversidad alfa basada en la riqueza de especies (S), el Índice de Simpson, Shannon-Wiener y el número efectivo de especies (N0, N1 y N2), la similitud se calculó con el Coeficiente Jaccard (I J ) y se determinó el Índice de Valor de Importancia (IVI). Para reconocer los usos de los árboles se aplicaron entrevistas (50 en TC y 10 en LC) estructuradas a los cafeticultores. Se registraron 35 especies, 16 en Tres Cruces y 22 en La Ciénega, de las cuales 83.3 % fueron nativas, por lo que se clasifica como manejo tradicional. Alnus acuminata en LC y Myrsine juergensenii en TC fueron las de mayor IVI. Los cafeticultores señalaron a 24 especies en TC y 14 en LC que proporcionan sombra, generan materia orgánica, frutos, flores y combustibles; las especies más empleadas son Clethra mexicana y A. acuminata.

Abstract The coffee (Coffea arabica) plantations of the Montaña de Guerrero region preserve the characteristics of a forest and also contribute to the generation of economic resources that help a large number of families to meet some of their basic needs. The objective of this work was to identify the structure and uses of shade species in coffee plantations in two Me'phaa communities in the Montaña de Guerrero region. Twelve plots in Tres Cruces (TC), Acatepec and La Ciénega (LC), Malinaltepec, were sampled using the point-center-square method; trees were measured for distance, height, crown cover and normal diameter. The alpha diversity was estimated based on species richness (S), Simpson's Index, Shannon-Wiener’s Index, and the effective number of species (N0, N1 and N2); similarity was calculated with the Jaccard index (J I ), and the Importance Value Index (IVI) was determined. In order to identify the uses of the trees, structured interviews (50 in TC and 10 in LC) were carried out with coffee growers. Thirty-five species were recorded -16 in Tres Cruces and 22 in La Ciénega-, of which 83.3 % were native; therefore, the region is classified as under traditional management. Alnus acuminata in LC and Myrsine juergensenii in TC had the highest IVI. Coffee growers reported 24 species in TC and 14 in LC that provide shade, generate organic matter, fruits, flowers, and fuel. The most commonly used species are Clethra mexicana and A. acuminata.

Resumo A fertilização das figueiras é realizada por muitos produtores da região de Torres Novas de forma intuitiva, refletindo-se em baixas produções e baixa qualidade dos frutos. Atendendo a este problema, foi objetivo deste estudo avaliar a produção, o crescimento e a queda dos figos, comparando a fertilização que é realizada com base na intuição do agricultor (tradicional) com a fertilização que é baseada na produção esperada, na análise de solos e de folhas do ano anterior e nos valores de referência (racional). Os resultados indicaram que a fertilização racional teve uma significativa influência na produtividade das figueiras da cultivar ‘Preto de Torres Novas’ e ainda no crescimento em diâmetro dos figos, induzindo maior formação de frutos e reduzindo a queda dos mesmos. Já no caso da cultivar ‘Pingo de Mel’, nenhuma das modalidades de fertilização mostrou um efeito considerável na produtividade e no crescimento em diâmetro dos frutos em ambos os anos. Não houve diferenças significativas na evolução do número de figos vindimos/ramo em 2021. Verificou-se, no entanto, uma redução da queda dos figos em ambos os anos nas figueiras que foram sujeitas a uma fertilização racional. Este estudo foi realizado no âmbito do projeto GoFigo Produção, iniciativa 321, financiado pelo Programa de Desenvolvimento Rural 2014-2020 que teve como objetivo melhorar a qualidade dos pomares de figueiras através da modernização das técnicas utilizadas e da eficiente utilização do solo.

Abstract The fertilization of fig trees is carried out intuitively by many producers in Torres Novas region, resulting in both low yields and low fruit quality. The objective of this study was to evaluate production, growth and figs shedding by comparing the farmers’ traditional fertilization with the rational fertilization, i.e. fertilization based on the expected production and the soil and leaf analysis of the previous year. The results showed that rational fertilization had a major impact on the productivity on the Preto de Torres Novas' cultivar. The figs were larger in diameter and dropped less. In 'Pingo de Mel' cultivar, none of the different fertilization methods showed a different effect on productivity and growth in either years. There were no differences in the development of the number of figs harvested per branch in 2021. With rational fertilization, however, a decrease in fig drop was recorded in both years. This study was carried out as part of the GoFigo Producão project funded by Programa de Desenvolvimento Rural 2014-2020, which aimed to improve the quality of fig orchards through the modernization of the techniques used and the efficient use of the soil.

Abstract Introduction: University dropout is now considered a complex phenomenon that goes beyond the number of students not enrolled and that is continuously growing, especially in the first years of study. Objective: In the present study, a prediction model combining Survival Analysis, Decision Trees, and Random Forest, under the Machine Learning philosophy, is proposed for the early diagnosis of possible factors causing dropout in university students. Methods: The proposal consists of 3 phases: the Survival Analysis that allows estimating the probability of permanence of the student (survival). Phase 2 starts from the probability value obtained in the previous phase and uses it as a response variable in the modeling process based on Decision Trees to establish survival patterns around the variables considered. Finally, in phase 3, the critical variables in the model are identified using the Random Forest. Results: The proposed methodology allowed the design of a prediction model to identify the main segmentation variables in behavior patterns of possible cases of academic dropout. Conclusion: Even though the proposal was developed considering a particular case of a Chilean university, the efficient combination of metaheuristics allows the extrapolation of the methodology to any context and academic reality. However, the conditions and needs of each institution must be considered.

Resumen Introducción: La deserción universitaria se considera actualmente como un fenómeno complejo que va más alla del número de estudiantes no matriculados, y que viene en continuo crecimiento sobre todo en los primeros años de estudio. Objetivo: En el presente estudio se propone un modelo de predicción que combina el Análisis de Supervivencia, Árboles de Decisión y Random Forest, bajo la filosofía de Machine Learning, para el diagnóstico temprano de los posibles factores de la deserción en estudiantes universitarios. Métodos: La propuesta consta de 3 fases: el Análisis de Supervivencia que permite estimar la probabilidad de permanencia del alumno (supervivencia). La fase 2 parte del valor de probabilidad obtenido en la fase anterior y lo utiliza como variable respuesta en el proceso de modelado basado en los árboles de decisión para establecer patrones de supervivencia en torno a las variables consideradas. Finalmente, en la fase 3 se identifican las variables más importantes en el modelo, utilizando Random Forest. Resultados: La metodología propuesta permitió diseñar un modelo de predicción, que identifica las principales variables de segmentación en patrones de comportamiento de posibles casos de deserción académica. Conclusión: Si bien la propuesta fue desarrollada considerando un caso particular de una universidad chilena, la eficiente combinación de la metaheurística permite la extrapolación de la metodología a cualquier contexto y realidad académica. Sin embargo, se deben considerar las condiciones y necesidades de cada institución.

Resumo Introdução: A deserção universitária é atualmente considerada um fenômeno complexo que vai além do número de estudantes não matriculados, e que vem em contínuo crescimento sobretudo nos primeiros anos de estudo. Objetivo: No presente estudo, é proposto um modelo de predição que combina Análise de Sobrevivência, Árvores de Decisão e Random Forest, sob a filosofia de Machine Learning, para o diagnóstico precoce dos possíveis fatores de deserção em estudantes universitários. Métodos: A proposta consiste em 3 fases: a Análise de Sobrevivência que permite estimar a probabilidade de permanência do aluno (sobrevivência). A fase 2 parte do valor de probabilidade obtido na fase anterior e o utiliza como variável resposta no processo de modelagem baseado em árvores de decisão para estabelecer padrões de sobrevivência em torno das variáveis consideradas. Finalmente, na fase 3, as variáveis críticas do modelo são identificadas usando Random Forest. Resultados: A metodologia proposta permitiu desenhar um modelo de previsão, que identifica as principais variáveis de segmentação em padrões de comportamento de possíveis casos de deserção acadêmica. Conclusão: Embora a proposta tenha sido desenvolvida a partir de um caso particular de uma universidade chilena, a combinação eficiente da meta-heurística permite a extrapolação da metodologia para qualquer contexto e realidade acadêmica. No entanto, devem ser consideradas as condições e necessidades de cada instituição.

Abstract In sampling of pests with low densities, it is common to obtain a large number of zeros, which is difficult to manage since the Poisson and negative binomial probability distributions are not suitable for modeling and equations to estimate the optimal sample size are not available. In this study model the excess of zeros by estimating parameters through the methods of moments and maximum likelihood of the zero-inflated Poisson and zero-inflated negative binomial distributions, and to derive equations to calculate the optimal sample size. Systematic sampling was used to select 100 trees per grove of Río Red grapefruit (Citrus paradisi Macfad) at Finca Sayula, Veracruz, Mexico (latitude 19.20722, longitude -96.35194), from June to July 2021 and January 2022. The number of leafminers (Phyllocnistis citrella Stainton) and aphids (Toxoptera citricida Kirkaldy) present in three leaves per shoot per tree, considered as a sample unit, was counted. Simulations were performed in RStudio with different proportions of zero (0.1, 0.4, and 0.6) to compare the parameters obtained in the field using the methods of moments and maximum likelihood. Equations were derived to estimate the optimal sample size in studies of pests with low densities, based on the zero-inflated Poisson and zero-inflated negative binomial probability distributions. The method of moments yields optimal sample sizes smaller than those obtained by maximum likelihood, because they distinguish the origin from zero, so its use is recommended.

Resumen En muestreos de plagas con densidades bajas es común obtener gran cantidad de ceros, lo que es difícil de manejar, ya que las distribuciones de probabilidad Poisson y binomial negativa no son adecuadas para su modelación y no se dispone de ecuaciones para estimar el tamaño de muestra óptimo. En este estudio se modelo el exceso de ceros mediante la estimación de parámetros a través de los métodos de momentos y de máxima verosimilitud de las distribuciones Poisson cero inflado y binomial negativa cero inflado, y derivar ecuaciones para calcular el tamaño de muestra óptima. Se utilizó muestreo sistemático para seleccionar 100 árboles por huerto de toronja (Citrus paradisi Macfad) Río Red, en la Finca Sayula, Veracruz, México (latitud 19.20722, longitud -96.35194), de junio a julio 2021 y enero 2022. Se contó el número de minadores (Phyllocnistis citrella Stainton) y pulgones (Toxoptera citricida Kirkaldy) presentes en tres hojas por brote por árbol, consideradas como unidad muestral. Se realizaron simulaciones en RStudio con diferentes proporciones de cero (0.1, 0.4 y 0.6) para comparar los parámetros obtenidos en campo, mediante el método de los momentos y máxima verosimilitud. Se derivaron ecuaciones para estimar el tamaño de muestra óptimo en estudios de plagas con densidades bajas, a partir de las distribuciones de probabilidad Poisson cero inflado y binomial negativa cero inflado. El método de los momentos arroja tamaños de muestra óptimos menores a aquellos obtenidos mediante máxima verosimilitud, debido a que distinguen el origen del cero, por lo que se recomienda su uso.

Resumen Las tierras secas representan el principal bioma terrestre, proveyendo numerosos servicios ecosistémicos a un ingente número de personas. En estos ambientes, los bosques son a menudo dominados por árboles de porte multi-fustal, explotados por los habitantes locales para obtener productos forestales útiles para su sustento. En los territorios del centro-oeste de Argentina, los bosques de Neltuma flexuosa (algarrobo) están distribuidos en diferentes unidades de paisaje, los que presentan variaciones en las características topográficas y edáficas. En este estudio reconstruimos, a través de métodos dendrocronológicos, el crecimiento, el intervalo para obtener productos maderables, y el turno biológico de corta en función de la variabilidad topo-edáfica en tres bosques diferentes de algarrobo. Los resultados indican que la heterogeneidad del paisaje modula el crecimiento radial de la especie, influenciando el incremento diamétrico y el turno de corta. En este sentido, se evidencia una tendencia decreciente en valores de productividad según un gradiente edáfico desde textura limosa a arenosa. Estos hallazgos proveen información novedosa y de utilidad para los planes de manejo forestal de los bosques de N. flexuosa, indicando la necesidad por considerar la heterogeneidad espacial establecidas por las unidades de paisaje/suelos en estudios relativos a la dinámica forestal de los bosques de tierras secas.

Abstract Drylands represent the main earth biome, providing ecosytemic services to a large number of people. Along these environments, woodlands are often dominated by multi-stemmed trees, which are exploited by local inhabitants to obtain forest products for their livelihood. In central-west Argentina, Neltuma flexuosa (algarrobo) woodlands are distributed across different landform units, varying in topographical and soil characteristics. This research aimed to reconstruct stem-growth time until harvestable diameter was achieved, and biological rotation age according to topo-edaphic variability in three algarrobo forests using dendrochronological methods. Results indicated that landform heterogeneity modulated species radial growth, influencing stem increments and cutting cycle period. In this sense, a decreasing trend in tree productivity emerged along a loamy-to-sandy textured soil gradient. These findings provide useful novel information for N. flexuosa forest management, suggesting the need to account for spatial landform/soil heterogeneity when examining desert forest dynamics.

Resumo O levantamento fitossociológico foi realizado durante o período 2018-2020. A área de pesquisa foi classificada em cinco zonas ecológicas com base no habitat, na fisionomia e na composição de espécies. O software Pc-Ord foi utilizado para análise de agrupamento e quatro comunidades de vegetação foram estabelecidas. A comunidade Quercus baloot-Quercus incana está situada em Sair, a uma altitude de 1.196 m (média ± SE) de altitude, com um ângulo de inclinação de 14,1° ± 0, e contém 11 espécies de árvores. A comunidade Pinus wallichiana-Ailanthus altissima teve um número relativamente pequeno de espécies de árvores relatadas em Shakawlie, em 1.556 m (média ± SE) de altitude, com um ângulo de inclinação de 17,5° ± 0. A comunidade de Pinus wallichiana-Quercus incana está distribuída em Wali Kandao e Mangi Kandao, em altitude de 2.030,5 m (média ± SE) e ângulo de inclinação de 19,2° ± 1,4. Esta comunidade possui um total de 21 espécies de árvores e é altamente diversificada. Da mesma forma, o grupo Populus alba-Platanus orientalis esteve presente em Banr Pate, com altitude de 1.613 m (média ± SE) e ângulo de inclinação de 16,3°. Os métodos de análise de componentes principais (PCA) e ordenação de escala multidimensional não métrica (NMS) foram aplicados para estudar as relações entre variáveis ecológicas e de solo com espécies arbóreas. A ordenação NMS do eixo 1 foi significativamente correlacionada com as porcentagens de Areia (p<0,2), Nitrogênio (p<0,1) e Chumbo (mg/kg) (r=0,876751, p<0,05), enquanto a ordenação do eixo 2 foi significativamente correlacionada com as porcentagens de Silte (p<0,2), Areia (p<0,2), Matéria Orgânica (p<0,2), Potássio (mg/kg) (r=0,882433, p<0,02), Ferro (mg/kg) (r=0,614833, p<0,2), Cálcio (mg/kg) (r=0,721712, p< 0,2) e Zinco (mg/kg) (r=0,609545, p<0,2). Da mesma forma, a ordenação PCA do eixo 1 revelou que estava significativamente correlacionada com fósforo e cálcio, e ângulo de inclinação, enquanto a do eixo 2 estava significativamente correlacionada com zinco e manganês, e altitude. 20182020. 20182020 2018 2020. 2020 2018-2020 habitat PcOrd Pc Ord estabelecidas balootQuercus baloot Sair 1196 196 1.19 média SE 141 14 14,1 0 wallichianaAilanthus wallichiana Ailanthus Shakawlie 1556 556 1.55 175 17 5 17,5 wallichianaQuercus 20305 030 2.030, 192 19 19,2 4 1,4 diversificada forma albaPlatanus alba Platanus Pate 1613 613 1.61 163 16 3 16,3° (PCA (NMS arbóreas p<0,2, p02 p p<0,2 , (p<0,2) p<0,1 p01 (p<0,1 mg/kg mgkg mg kg (mg/kg r=0,876751, r0876751 r 876751 (r=0,876751 p<0,05, p005 p<0,05 05 p<0,05) r=0,882433, r0882433 882433 (r=0,882433 p<0,02, p002 p<0,02 02 p<0,02) r=0,614833, r0614833 614833 (r=0,614833 p<0,2) r=0,721712, r0721712 721712 (r=0,721712 0,2 r=0,609545, r0609545 609545 (r=0,609545 p<0,2. . cálcio manganês 2018202 201 202 2018-202 119 1.1 14, 155 55 1.5 17, 2030 03 2.030 19, 1, 161 61 1.6 16,3 p0 p<0, (p<0,2 (p<0, r=0,876751 r087675 87675 (r=0,87675 p00 p<0,0 r=0,882433 r088243 88243 (r=0,88243 r=0,614833 r061483 61483 (r=0,61483 r=0,721712 r072171 72171 (r=0,72171 r=0,609545 r060954 60954 (r=0,60954 201820 20 2018-20 1. 15 203 2.03 6 16, p<0 (p<0 r=0,87675 r08767 8767 (r=0,8767 r=0,88243 r08824 8824 (r=0,8824 r=0,61483 r06148 6148 (r=0,6148 r=0,72171 r07217 7217 (r=0,7217 r=0,60954 r06095 6095 (r=0,6095 20182 2018-2 2.0 (p< r=0,8767 r0876 876 (r=0,876 r=0,8824 r0882 882 (r=0,882 r=0,6148 r0614 614 (r=0,614 r=0,7217 r0721 721 (r=0,721 r=0,6095 r0609 609 (r=0,609 2018- 2. (p r=0,876 r087 87 (r=0,87 r=0,882 r088 88 (r=0,88 r=0,614 r061 (r=0,61 r=0,721 r072 72 (r=0,72 r=0,609 r060 60 (r=0,60 r=0,87 r08 8 (r=0,8 r=0,88 r=0,61 r06 (r=0,6 r=0,72 r07 7 (r=0,7 r=0,60 r=0,8 r0 (r=0, r=0,6 r=0,7 r=0, (r=0 r=0 (r= r= (r

Abstract The phytosociological survey was conducted during 2018-2020. The research area was classified into five ecological zones based on habitat, physiognomy and species composition. Pc-Ord software was used for cluster analysis and four vegetation communities were established. The Quercus baloot-Quercus incana community is situated in Sair at an altitude of 1196 (mean ± SE) m altitude with a 14.1 ± 0 slope angle and contains eleven tree species. The Pinus wallichiana- Ailanthus altissima community had a relatively small number of tree species reported in Shakawlie at 1556 (mean ± SE) with a 17.5 ± 0 slope angle. The Pinus wallichiana- Quercus incana community is distributed in Wali Kandao and Mangi Kandao at altitudes of 2030.5 (mean ± SE) m and the slope angle was 19.2 ± 1.4. This community possesses a total of twenty-one tree species and is highly diverse. Similarly, the Populus alba - Platanus orientalis group was present in Banr Pate, with an altitude of 1613 (mean ± SE) m and a 16.3 slope angle. The principal component analysis (PCA) and non-metric multidimensional scaling (NMS) ordination methods were applied to study the relationships between ecological and soil variables with trees species. The NMS ordination of axis 1 was significantly correlated with Sand% (p<0.2), Nitrogen% (p<0.1) and Pb (mg/kg) (r= 0.876751, p<0.05), while the ordination of axis 2 was significantly correlated with Silt% (p<0.2), Sand% (p<0.2), Organic matter% (p<0.2), K (mg/kg) (r=0.882433, p<0.02), Fe (mg/kg)(r=0.614833, p<0.2), Ca (mg/kg) (r=0.721712, p< 0.2) and Zn (mg/kg) (r=0.609545, p<0.2). Similarly, the PCA ordination of axis 1 revealed that it was significantly correlated with phosphorus, calcium and slope angle, while that of axis 2 was significantly correlated with altitude, zinc and manganese. 20182020. 20182020 2018 2020. 2020 2018-2020 habitat composition PcOrd Pc Ord established balootQuercus baloot 119 mean SE 141 14 14. wallichiana 155 175 17 5 17. 20305 2030 2030. 192 19 19. 4 1.4 twentyone twenty one diverse Similarly Pate 161 163 16 3 16. (PCA nonmetric non metric (NMS Sand p<0.2, p02 p p<0.2 , (p<0.2) Nitrogen p<0.1 p01 (p<0.1 mg/kg mgkg mg kg (mg/kg r= r (r 0876751 876751 0.876751 p<0.05, p005 p<0.05 05 p<0.05) Silt matter r=0.882433, r0882433 882433 (r=0.882433 p<0.02, p002 p<0.02 02 p<0.02) mg/kgr=0.614833, mgkgr0614833 mgkgr r=0.614833, 614833 (mg/kg)(r=0.614833 p<0.2) r=0.721712, r0721712 721712 (r=0.721712 0.2 r=0.609545, r0609545 609545 (r=0.609545 p<0.2. . phosphorus manganese 2018202 201 202 2018-202 11 15 203 1. p0 p<0. (p<0.2 (p<0. 087675 87675 0.87675 p00 p<0.0 r=0.882433 r088243 88243 (r=0.88243 kgr mg/kgr=0.614833 mgkgr061483 r0614833 r=0.614833 61483 (mg/kg)(r=0.61483 r=0.721712 r072171 72171 (r=0.72171 0. r=0.609545 r060954 60954 (r=0.60954 201820 20 2018-20 p<0 (p<0 08767 8767 0.8767 r=0.88243 r08824 8824 (r=0.8824 mg/kgr=0.61483 mgkgr06148 r061483 r=0.61483 6148 (mg/kg)(r=0.6148 r=0.72171 r07217 7217 (r=0.7217 r=0.60954 r06095 6095 (r=0.6095 20182 2018-2 (p< 0876 876 0.876 r=0.8824 r0882 882 (r=0.882 mg/kgr=0.6148 mgkgr0614 r06148 r=0.6148 614 (mg/kg)(r=0.614 r=0.7217 r0721 721 (r=0.721 r=0.6095 r0609 609 (r=0.609 2018- (p 087 87 0.87 r=0.882 r088 88 (r=0.88 mg/kgr=0.614 mgkgr061 r0614 r=0.614 61 (mg/kg)(r=0.61 r=0.721 r072 72 (r=0.72 r=0.609 r060 60 (r=0.60 08 8 0.8 r=0.88 r08 (r=0.8 mg/kgr=0.61 mgkgr06 r061 r=0.61 6 (mg/kg)(r=0.6 r=0.72 r07 7 (r=0.7 r=0.60 r06 (r=0.6 r=0.8 r0 (r=0. mg/kgr=0.6 mgkgr0 r=0.6 (mg/kg)(r=0. r=0.7 r=0. (r=0 mg/kgr=0. (mg/kg)(r=0 r=0 mg/kgr=0 (mg/kg)(r= mg/kgr= (mg/kg)(r mg/kgr

Resumo Insetos galhadores são abundantes na natureza, encontrados em muitos ecossistemas globalmente, com espécies atacando plantas de importância econômica. Os efeitos de herbívoros de alimentação livre na abundância de insetos galhadores em árvores de Caryocar brasiliense (Caryocaraceae) no Cerrado brasileiro (Savana) foram estudados. A porcentagem de desfolha e o número de ácaros fitófagos ou de Hemiptera fitófagos correlacionaram-se, negativamente, com a percentagem de folhas galhadas e de adultos do parasitoide Eurytoma sp. (Hymenoptera: Eurytomidae), respectivamente. Porcentagem de folhas galhadas e o número de Eurytoma sp. adultos e ácaros fitófagos correlacionaram-se, positivamente, com o de aranhas. Os números de ácaros e fitófagos Hemiptera correlacionaram-se, positivamente, com os de joaninhas e Sycophila sp. (Hymenoptera: Eurytomidae), respectivamente. O número de adultos de Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) correlacionou-se, negativamente, com Sycophila sp. O número de Agistemus sp. (Acari: Stigmaeidae) correlacionou-se, negativa e positivamente, com os de joaninhas e ácaros fitófagos, respectivamente. Herbívoros de alimentação livre afetaram a presença de insetos galhadores (Hymenoptera) em árvores de C. brasiliense, competindo por alimento e espaço. O mesmo foi observado entre dois parasitoides de Eurytoma sp., o que pode reduzir o controle biológico natural dessa praga.

Abstract Galling insects are abundant in nature, found in many ecosystems globally, with species attacking plants of economic importance. We studied the effects of free-feeding organisms on the abundance of galling insects on Caryocar brasiliense (Caryocaraceae) trees in the Brazilian Cerrado (Savanna). Percentage of defoliation and the number of phytophagous mites or number of phytophagous Hemiptera correlated negatively with percentage of galled leaves and the parasitoid Eurytoma sp. (Hymenoptera: Eurytomidae) adults, respectively. Percentage of galled leaves and the numbers of Eurytoma sp. adults and phytophagous mites correlated positively with spiders. Numbers of mites and Hemiptera phytophagous correlated positively with those of lady beetles and Sycophila sp. (Hymenoptera: Eurytomidae), respectively. The number of Ablerus magistretti Blanchard (Hymenoptera: Aphelinidae) adults correlated negatively with Sycophila sp. The number of Agistemus sp. (Acari: Stigmaeidae) correlated, negatively and positively, with those of lady beetles and phytophagous mites, respectively. Free-feeding herbivores affected the presence of galling insects (Hymenoptera) on C. brasiliense trees, competing for food and space. The same was observed between two parasitoids of Eurytoma sp. galling insect, which can reduce the natural biological control of this pest.

ABSTRACT This study aimed to evaluate the use of decision trees to select sows based on the production parameters of parity order (PO) 1 sows from a commercial herd. Data were collected at a piglet production unit with a capacity of housing 5,500 sows in collective pens. Piglet production and sow culling information was collected from PO1 and PO2 sows. The period from January 2017 to March 2020 was analyzed. The correlation analysis was used to identify the influence of the production parameters on sow culling after exploring the database using the graphical analysis and descriptive statistics. The ANOVA was applied to evaluate differences in the response variables between culled and unculled sows. Two models were proposed using the decision tree method: model 1 referred to sow culling, and model 2 comprised the total number of liveborn piglets (TBA). The calculated value was close to 0, although the correlations of the production parameters with culling were statistically significant. The mean number of weaned piglets was higher for unculled sows in PO1 (p < 0.05). The number of weaned piglets, total number of liveborn piglets, and weaning-service interval did not differ in the unculled and culled sows in PO2 (p > 0.05). Using a confusion matrix as a metric tool, the decision tree method used in this study provided consistent results for this database, indicating its possible use for decision-making in sow selection. PO (PO herd 5500 5 500 5,50 pens 201 202 analyzed statistics TBA. TBA . (TBA) 0 significant p 0.05. 005 0.05 05 0.05) weaningservice weaning service tool decisionmaking making selection 550 50 5,5 20 (TBA 00 0.0 55 5, 0.