Abstract: Despite all the knowledge generated about grafting techniques in plant species, there is little research that evaluates the results found. The objective of this work was to analyze, through bibliometric techniques, the information published in scientific articles in which a grafting technique was evaluated, to identify analysis methodologies, types of grafts, plant species, and the application of the results found. The keyword used for the search of scientific articles was ‘grafting’, and publications up to December 2022 were considered. From 1994 to 2022, 293 scientific articles were identified, the frequency of their publication showed an exponential trend (R2 = 0,54). It was found that variables associated with rootstock, graft and survival of the newly formed plant are evaluated, with an increasing use of multivariate techniques in order to detect the most significant variables. Eleven grafting techniques were documented: bark grafting, cleft grafting, splice grafting, whip and tongue grafting, budding, in vitro grafting, micrografting, T-budding, side-veneer grafting, chip budding, and tube grafting. Fruit (citrus), horticultural (tomato), forest (walnut), and ornamental (rose) crops were the most widely analyzed. However, 63,47% of the scientific articles were limited to descriptive analyses on success rate, compatibility and survival rate of vegetative materials. This provides the opportunity to conduct research on genetic improvement processes in the search for agronomic traits of interest (fruit and growth), or on genetic diversity aimed to improve productivity and/or conservation.

Resumen: A pesar de todo el conocimiento generado en torno a las técnicas de injerto en especies vegetales, existe poca investigación que evalúe los resultados encontrados. El objetivo de este trabajo fue analizar, mediante técnicas bibliométricas, la información publicada en artículos científicos donde se evalúo alguna técnica de injerto, para identificar metodologías de análisis, tipos de injertos, especies vegetales y la aplicación de los resultados encontrados. La palabra clave utilizada para la búsqueda de los artículos científicos fue ‘grafting’, y se consideraron publicaciones hasta diciembre de 2022. De 1994 a 2022 se identificaron 293 artículos científicos, la frecuencia de su publicación mostró una tendencia exponencial (R2 = 0,54). Se encontró que se evalúan variables asociadas al portainjerto, injerto y sobrevivencia de la nueva planta formada, que son evaluadas cada vez con mayor frecuencia con técnicas multivariadas por el interés de detectar las variables más significativas a partir de un número elevado de variables analizadas. Se documentaron 11 técnicas de injerto: púa, hendidura, empalme, inglés, yema, in vitro, microinjerto, en T, chapado, chip y entube. Las especies de mayor análisis correspondieron a frutícolas (cítricos), hortícolas (tomate), forestal (nogal), y ornato (rosa). Sin embargo, el 63,47% de los artículos científicos se limitaron a hacer análisis descriptivos sobre prendimiento, compatibilidad y sobrevivencia de los materiales vegetativos. Lo anterior, deja un área de oportunidad para desarrollar investigación sobre los procesos de mejora genética en la búsqueda de caracteres agronómicos de interés (fruto y crecimiento), o bien en la diversidad genética orientada a la productividad y/o conservación.

ABSTRACT An important aspect in the study and understanding of the physical phenomena involved in water movement in the soil-plant system is the need to carry out the hydrodynamic characterization (HC) of non-saturated field soils. Studies of this type have been widely developed in soils of temperate climates, but they are infrequent in the tropics, hence there is a need for further research in tropical Vertisols under field conditions. Hydrodynamic characterization consists of finding the functional relationship between soil hydraulic conductivity (K), matric head (h) and soil moisture content (θ), widely known as K(θ) and h(θ) relationships, being the main objective of this study. The instantaneous profile method (IPM) was applied, in which splines were used for the HC of a bare, tropical agricultural field soil classified as a Vertisol. Field measurements of h and θ were made at five different soil depths (0.15, 0.30, 0.45, 0.60 and 0.90 m) and values of K at the same depths were estimated with the IPM, which allowed for the estimation of pairs of values of the K(θ) relationships in the soil profile. Unlike in other studies with the same objective, the use of splines was proposed to represent the spatial variation of the H(z) and θ(z) functions in the IPM. Subsequently, the van Genuchten equation was adjusted to the specific values determined for the h(θ) relations (r2 value ranged from 0.65 to 0.87), and the Ks values and the point data of K and θ were used to estimate the accuracy of the equation proposed by Mualem–van Genuchten (M-vG): in this case negative values for the exponent l of the M-vG function were determined for the five soil depths under study, ranging from –7.04 (0.45 m deep), to -13.26 (0.90 m deep). In addition, pedotransfer functions for tropical soils proposed in the literature, based on different soil physical properties, were used to estimate the h(θ) and K(θ) relationships and the saturated hydraulic conductivity (Ks). Best square root of the mean squared error (SRMSEθ) observed was 0.02853 cm3 cm-3 at 0.15 m depth and 0.02262 cm3 cm-3 at 0.9 m depth for h(θ) relations, and in all cases, the SRMSEk values are less than 0.0018 m day-1 for K(θ) relationships. The results reveal the utility of splines in the IPM for characterizing the soil profile K(θ) relationships in field studies, as well as the need for more research to the generation of pedotransfer functions in tropical Vertisols.

Abstract The dynamics of land and vegetation use in Poza Rica, Veracruz, from 1997 to 2016 were analyzed and related to the perception that the inhabitants of the city have regarding the ecosystem services provided by green areas (GA). Thus, the GAs were georeferenced and by means of cluster sampling, the number of trees in the city was estimated, which allowed the construction of an Urban Green Index (UGI). Additionally, 100 residents of different paid activities were surveyed: academics (25), housewives (21), merchants (37) and industrialists (17). Results indicate that the urban sprawl increased by 98 %, from 1 587 ha in 1997 to 3 145 ha in 2016, the areas that were reconverted were mostly areas agriculture and livestock. This fact directly impacts the UGI, which turned out to be 12.21830 m2 per cápita and 0.13527 trees per inhabitant, with negative annual average growth rates for both UGI: -0.83 and -0.01, respectively. All respondents recognize the importance of green areas in the city, although only 52 % know their positive effects on the regulation of temperature, hydrological cycle and air quality Scholars, housewives and merchants showed greater interest in preserving and increasing GA in the city. Environmental education stood out as a priority axis to ensure that citizens respect the GA, and eventually increase their number.

Resumen Se analizó la dinámica de uso de suelo y vegetación en Poza Rica, Veracruz, de 1997 a 2016 y se relacionó con la percepción que los habitantes de la ciudad tienen respecto a los servicios ecosistémicos que proveen las áreas verdes (AV). Para ello se georreferenciaron las AV y, mediante un muestreo por conglomerados, se estimó el número de árboles, lo que permitió construir un Índice Verde Urbano (IVU). Adicionalmente, se encuestó a 100 pobladores dedicados a diferentes actividades remuneradas: académicos (25), amas de casa (21), comerciantes (37) e industriales (17). Los resultados indican que la mancha urbana se incrementó 98 %, al pasar de 1 587 ha en 1997 a 3 145 ha en 2016; las áreas que se reconvirtieron fueron, en su mayoría, zonas destinadas a la agricultura y la ganadería. Este hecho impacta directamente en el IVU que resultó ser de 12.21830 m2 per capita y 0.13 527 árboles por habitante, con tasas medias de crecimiento anual negativas para ambos IVU: -0.83 y -0.01, respectivamente. La totalidad de los encuestados reconoce la importancia de las áreas verdes en la ciudad, aunque solo 52 % conoce sus efectos positivos en la regulación de la temperatura, el ciclo hidrológico y la calidad del aire. Los académicos, amas de casa y comerciantes mostraron mayor interés por conservar e incrementarlas AV. La educación ambiental destacó como un eje prioritario para lograr que los ciudadanos respeten las AV, y eventualmente se incremente su número.

Abstract: The federal government, through the General Direction of Tropical Zones of the Secretariat of Agriculture, Livestock, Rural Development, Fisheries, and Food (SAGARPA), has fostered the creation of 20,000 ha of Robusta coffee crops in the south-southeast states. As part of this initiative, the present study is done to determine what areas of the state of Tabasco are better suited for this type of coffee to prosper successfully and what the future impacts of climate change mid XXI century would be on its adaptation and yield. Thus, the objective of the present study was to determine the best areas, from the point of view of climate and soil, to grow Robusta coffee (Coffea canephora P.) in the state of Tabasco, as well as its vulnerability to a possible climate change in the middle of the present century. This was done using the Agro-Ecological Zoning methodology (AEZ) proposed by the FAO for the current conditions and for the worst-case scenario of climate change (RCP8.5) expected for mid XXI century. Also, the potential yields for three levels of input (low, medium, and high) were estimated in the areas that resulted to be very apt for both climatic conditions. The results indicate that if there were to be a mean daily increase in temperature of 1.6 ºC by the year 2050, under the worst-case scenario (RCP8.5), the very apt surface to grow Robusta coffee in the state of Tabasco is not modified. However, the mean potential yields would decrease by 41% by the year 2050 due to the effect of the increase in daytime temperatures on the maximum photosynthetic ratio.

Resumen: El gobierno federal a través de la Dirección General de Zonas Tropicales de la Secretaría de Agricultura, Ganadería, Desarrollo Rural, Pesca y Alimentación (SAGARPA), ha venido impulsando la apertura de 20,000 ha del cultivo de café robusta en los estados del sur-sureste. Como parte de esa iniciativa se realiza el presente estudio para determinar en qué áreas del estado de Tabasco este tipo de café puede prosperar exitosamente y cuáles serían los impactos del cambio climático a mitad del siglo XXI, en su adaptación y rendimiento. Así, el objetivo del presente estudio fue: determinar las mejores áreas desde el punto de vista de clima y suelo, para cultivar café tipo robusta (Coffea canephora P.) en el estado de Tabasco y su posible vulnerabilidad al cambio climático a mediados del presente siglo. Lo anterior se realizó utilizando la metodología de Zonificación Agro-Ecológica (ZAE) propuesta por la FAO para las condiciones actúales y para el escenario de cambio climático (RCP8.5), esperado a mediados del siglo XXI. Asimismo, se estimaron los rendimientos potenciales para tres niveles de insumo (bajo, medio y alto) en las áreas resultantes muy aptas, para ambas condiciones climáticas. Los resultados indican que de ocurrir un incremento promedio diario de 1.6 ºC para el año 2050, bajo el peor escenario (RCP8.5), la superficie muy apta para cultivar café tipo robusta en el estado de Tabasco no se modifica. En cambio, los rendimientos potenciales promedio disminuirán en 41 % para el año 2050, debido al efecto del incremento de las temperaturas diurnas sobre la tasa fotosintética máxima.

Abstract Atmosphere-Ocean General Circulation Model (AOGCM's) at regional level and for different scenarios, indicate that by the end of this century, in Tabasco the temperature can increase from 1 to 3.8 °C and annual precipitation can decrease to 14.4%. That is what regional scale models report. Little has been investigated with observed data at regional level to compare these scenarios with what has happened in reality. The objective was to determine whether the meteorological data for the period of 1961-2010 recorded any trend of change in maximum, minimum, average temperature and precipitation and thus determine the direction and magnitude of change at regional and state level. The results shown in the graphs and tables in this study indicate that during the time period under study, there is evidence of change over time for the variables analyzed. It was found that change trends are not uniform, but contradictory for different variables and studied localities. In some localities the change of a single variable is positive and in others negative. Statewide, the average temperature has increased 0.9 °C over the period under study, with fluctuations -0.6 °C to 2.5 °C between state regions. Also, for the same period, there was an increase in the anomaly of the average annual total precipitation of 0.5% with fluctuations between regions of -12.1% to 10.2%.

Resumen Modelos ensamblados de Circulación General de la Atmósfera y Océano Acoplados (AOGCM’s) a nivel regional y para diferentes escenarios, indican que para finales del presente siglo, para Tabasco la temperatura puede incrementarse desde 1 a 3.8 ºC y la precipitación total anual puede reducirse hasta 14.4%. Eso es lo que modelos a escala regional reportan. Poco se ha investigado con datos observados, a nivel regional para comparar esos escenarios con lo que ha ocurrido en la realidad. El objetivo fue determinar si los datos meteorológicos durante el periodo de 1961 a 2010 registran alguna tendencia de cambio en la temperatura máxima, temperatura mínima, temperatura media y la precipitación y con ello determinar el sentido y magnitud del cambio a nivel regional y estatal. Los resultados que se muestran en las gráficas y cuadros del presente estudio indican que durante el periodo de tiempo estudiado, sí existe evidencia de cambio respecto al tiempo para las variables analizadas. Se encontró que las tendencias de cambio no son uniformes, sino contradictorias para las diferentes variables y localidades estudiadas. En unas localidades el cambio de una misma variable es positivo y en otros negativos. A nivel estatal, la temperatura media anual se ha incrementado 0.9 ºC durante el periodo estudiado, con fluctuaciones -0.6 ºC a 2.5 ºC entre regiones del estado. Asimismo, para el mismo periodo, se tuvo un incremento en la anomalía de la precipitación total promedio anual de 0.5% con fluctuaciones las regiones de -12.1% a 10.2%.

The exponential growth of energy demand worldwide, the depletion of oil reserves and the severe pollutants problems caused by industry that favors greenhouse effect, evidence the need to increase the supply of oils for biodiesel production. This sets a new overview for studying non-edible oilseeds species. An alternative is barbados nut or piñon (Jatropha curcas) crop, perennial bush that is native from Mexico and Central America, grows in most of tropical countries, and it is considered like one of the non-conventional oilseed crops with great expectations for obtaining biodiesel. The barbados nut (Jatropha curcas) seeds have an outstanding characteristic: their high oil content allows converting it to liquid biofuel, and also the shell can be transformed into biogas and biofertilizers. Jatropha curcas is a green option to reforest degraded soils and to control erosion, as well as an option to diversify agricultural systems (crop rotation). On the other hand, in several scientific studies it is reported a wide variation in yields, due lack of study of plant's genetics, the agronomic handling, as well to the misunderstanding that exists in some countries in the field of zones with best agroecological ability to set the crop. The agroecological zoning (ZAE) refers to a division of land surface and weather into smaller units, that have similar characteristics related to its ability, potential yield and environmental impact. The aim of this paper is to define the zones with different agroecological abilities to set the Jatropha curcas crop, in the state of Tabasco. In order to accomplish this, four types of abilities were defined: optimal, proper, marginal by thermal or water deficit, and marginal by thermal or water excess. The agroecological zoning (ZAE) proposed in this paper defines zones based on combinations of soil, physiography, weather characteristics of temperature, rainfall and growth rate. An agroclimatic zoning is a zone with characteristics related to weather and crop systems, for our study the database of ERIC III (Extractor Rápido de Información Climatológica) was used, reporting for Tabasco a total of 93 meteorological stations. Nevertheless, only 35 stations were selected, since the other had inconsistencies in their information. From those 35 stations, a weather database was created, considering the information of historical series in a daily basis, like minimum and maximum temperatures, rainfall and evaporation (1950 - 2003 period). The edaphoclimatic zoning consisted in assessing the soil resource based in the units and subdivisions of soil from FAO/UNESCO system. In order to fulfill the zoning, cartographic data of soils subunits was consolidated, including texture, slope, soil depth, and its fertility, whose edaphological properties were compared to FAO's Jatropha curcas crop requirements and optimal level was assigned. The tool used for cartography elaboration was ArcMap GIS Software, which consists of computer mapping system that relates locations with agroclimatic information equal to Jatropha curcas crop requirements, which were defined like areas with ability, and according to this maps were prepared at a scale of 1:250 000 of every climatic element. The interpolation for the calculation of isolines was made by Kriging method, embedded within ArcMap software, which ease the handling and superposition of theme information layers of weather and soil. The yearly average analysis of temperature corroborated that whole Tabasco state has optimal ability and the rainfall analysis showed a surface of 2 229 631 ha with optimal ability. About soil resource there were detected 37 subunits of soil with optimal ability, adding a surface of 945 462 ha. After analyzing the maps between optimal characteristic abilities (temperature, rainfall and growth rate) and edaphological, there were detected 833 181 ha with optmial agroecological ability, therefore in the state of Tabasco is feasible the crop of this oilseed to produce biofuels.

El agotamiento de las reservas petrolíferas y la creciente demanda energética mundial, ponen en evidencia la necesidad de ampliar la oferta de aceites para la producción de biodiesel. El objetivo principal de este estudio, fue determinar las zonas aptas con diferentes aptitudes agroecológicas, para establecer el cultivo de Jatropha curcas en el estado de Tabasco. Para ello se definieron cuatro tipos de aptitud: óptima, adecuada, marginal por déficit térmico e hídrico, y marginal por exceso térmico e hídrico. Para el recurso suelo se consideró la fertilidad, profundidad, textura y pH, y se utilizó la clase de aptitud óptima. La delimitación de estas zonas se generó mediante la implementación de un sistema de información geográfica (SIG), el cual facilitó la manipulación y sobreposición de capas de información temática de clima y suelo. El análisis promedio anual de temperatura demostró que todo el estado de Tabasco presenta aptitud óptima y con el de precipitación se obtuvo una superficie de 2 229 631 ha con aptitud óptima. En lo referente al recurso suelo se detectaron 37 subunidades de suelo con aptitud óptima, sumando una superficie de 945 462 ha. Al realizar el álgebra de mapas entre las aptitudes óptimas climáticas (temperatura, precipitación y periodo de crecimiento) y edafológicas, se obtuvieron 833 181 ha con aptitud agroecológica óptima, por lo que en el estado de Tabasco es factible cultivar esta oleaginosa para producir biocombustibles.