https://www.terralatinoamericana.org.mx/index.php/terra/issue/feed REVISTA TERRA LATINOAMERICANA 2021-03-31T04:21:47+00:00 Dr. Bernardo Murillo Amador editor@terralatinoamericana.org.mx Open Journal Systems <h4><span style="float: right; color: #111111; font-family: 'helvetica neue',helvetica,arial,verdana,sans-serif; font-size: 14.4px; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: 18.72px; text-align: justify; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; display: inline ! important; background-color: #ffffff;">ISSN Electrónico 2395 - 8030.</span></h4> https://www.terralatinoamericana.org.mx/index.php/terra/article/view/919 Portada Interna 39 2021-01-17T21:11:04+00:00 Rosa Maria López-Atilano formato.ed.terra@gmail.com 2021-01-18T00:00:00+00:00 Copyright (c) https://www.terralatinoamericana.org.mx/index.php/terra/article/view/920 Editorial Committee 39 2021-01-17T21:12:37+00:00 Rosa Maria López-Atilano formato.ed.terra@gmail.com 2021-01-18T00:00:00+00:00 Copyright (c) https://www.terralatinoamericana.org.mx/index.php/terra/article/view/918 Index 39 2021-02-13T00:48:11+00:00 Rosa Maria López-Atilano formato.ed.terra@gmail.com 2021-01-18T00:00:00+00:00 Copyright (c) https://www.terralatinoamericana.org.mx/index.php/terra/article/view/781 Pumice, tezontle and nutritive solutions in cherry tomato crop 2021-03-31T04:21:27+00:00 Jonás Alán Luna-Fletes jonazzinn@hotmail.com Elia Cruz-Crespo ccruzc2006@yahoo.com.mx Álvaro Can-Chulim canchulim@yahoo.com.mx <p>The use of low cost local mineral substrates and nutrient solutions with the suitable chemical composition may be the alternative to maximize the production potential of cherry tomato (Solanum lycopersicum L.). The objective of this study was to evaluate substrates from the area of the State of Nayarit, Mexico in combination with nutritional solutions, on growth, nutritional content and cherry tomato production. The experimental design was completely randomized with two-factor arrangement. The factors were pumice and tezontle substrates and Steiner and Castellanos nutrient solutions, which originated four treatments with 11 repetitions where one of them was a plant with two stems. The variables plant height, stem diameter, leaf area, dry aerial part biomass, dry root biomass, fruit production per plant, soil plant analysis development (SPAD) units and leaf nutrient content (N, P and K) were determined. The results showed that Steiner nutritive solution increased fruit production and also growth evaluated in plant height, stem diameter and dry root biomass. The nutritional content of N, P and K was higher with Castellanos solution. In the pumice substrate, fruit production, plant growth and nutrient content were higher in relation to tezontle plants. The study concluded that pumice substrate in combination with Steiner nutritive solution was the most viable for cherry tomato, since it favored plant growth and fruit production.</p> 2021-03-31T04:14:32+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/766 Fertility and soil quality index of the San Pedro river basin in Nayarit 2021-03-31T04:21:36+00:00 Óscar Germán Martínez-Rodríguez ogmartinez.r@gmail.com Álvaro Can-Chulim canchulim@yahoo.com.mx Héctor Manuel Ortega-Escobar manueloe@colpos.mx José Irán Bojórquez-Serrano iranbojorquez@hotmail.com Elia Cruz-Crespo ccruzc2006@yahoo.com.mx Juan Diego García-Paredes digapar@gmail.com Alberto Madueño-Molina Albertomad2008@gmail.com <p>The agricultural area of the San Pedro River basin in Nayarit is a coastal plain with alluvial soils, subjected to flooding, deposition and different processes that control nutrient input and soil fertility. The objective of this investigation was to evaluate soil properties to diagnose fertility and determine the soil quality index considering the parameters pH, MO, N, P, K, CIC, Ca and Mg. Samples were carried out at 30 cm in depth in 38 sites in June 2017 and 45 in 2018; pH, EC, texture, Da, CO, MO, inorganic N, P, CIC and interchangeable bases were measured. The mean, maximum and minimum values were pH 5.78, 8.15 and 3.28; MO 1.58, 3.02 and 0.65%; inorganic N 22.5, 43.6 and 3.5 mg kg‑1; P Olsen 32.5, 67.4 and 1.4 mg kg‑1; K 0.45, 0.80 and 0.10 cmolc kg-1, respectively. The average EC was 1.39 dS m-1 and indicate that no salinity problems existed; 73% of the sites were from sandy to loamy texture. The Soil Quality Index (SQI) indicated that the basin had a medium fertility level; average SQI was 0.64; 17% of the sites had low fertility with pH from 3.28‑5.40, MO 0.81-1.20%, N 10-20 and P 5-10 mg kg‑1; 42% medium, pH 6.41-7.30, MO 2.01‑2.50, N 40-60 and P 15-20 mg kg-1; 36% moderately high, and 5% high with pH 8.20-8.80, MO 3.01-4.00, N 100-150 and P 25‑35 mg kg-1. The SQI distribution showed that in the upper plain, soils were from low to medium fertility; in the intermediate and low plains from medium to high fertility, and in lower elevation parts, fertility was limited by the interaction between the continental and marine systems that salinize soils.</p> 2021-03-31T03:59:35+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/899 Estimation of fractional vegetation cover and canopy nitrogen content in corn by remote sensing 2021-03-31T04:21:31+00:00 José Manuel Salvador-Castillo slcastillo990@gmail.com Martín Alejandro Bolaños-González martinb72@gmail.com Enrique Palacios-Vélez epalaciospave80@gmail.com Luis Alberto Palacios-Sánchez luis.palacios59@gmail.com Adolfo López-Pérez adolfholp@gmail.com José Miguel Muñoz-Pérez jmiguel.muper@gmail.com <p>Nitrogen use efficiency of nitrogen use in agriculture is very low, causing environmental problems and low crop productivity, therefore, knowing the spatial and temporal distribution of biophysical variables such as the fractional vegetation cover (FVC) and the canopy nitrogen content (CNC) of the crops will provide valuable information to improve this condition. The use of freely accessible satellite imagery, such as Sentinel-2 (S-2) images, can facilitate this task. Due to the above, a study was carried out in six corn plots grown by producers in Texcoco de Mora, Estado de Mexico. The first objective was to investigate the relationship between spectral indices, estimated from the reflectance measured with a multispectral radiometer at surface level and S-2 images, with FVC, estimated by digital photographs through the Canopeo mobile application. The second objective was to obtain a linear model that estimated the CNC from the analysis of different spectral indices. Two models were generated to estimate FVC, from the radiometric information at surface level, their validation yielded a high value of R2 = 0.92 and a RMSE = 7.3% between measured and estimated FVC data; however, in the case of the data estimated with S-2 images, lower values of R2 = 0.67 and RMSE = 17.6% were obtained, which was attributed to a possible effect of the atmosphere, since the study period coincided with the rainy season. Finally, to estimate the CNC, the best results were obtained with the model generated from ClGreen, in which an R2 of 0.91 and a RMSE of 0.63 g m-2 were obtained, when comparing the CNC measured in relation to the estimate.</p> 2021-03-31T04:09:29+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/844 Patterns for estimating soil fertility using Pfeiffer´s chromatography technique 2021-03-31T04:21:47+00:00 Adriana Hernández-Rodríguez aernande@uach.mx Brisany Ochoa-Rodríguez brisanyochoar@gmail.com Dámaris Ojeda-Barrios dojeda@uach.mx Jorge Jiménez-Castro jajimenezuach@gmail.com Rocío Sánchez-Rosales rocsan62@gmail.com María Janeth Rodríguez-Roque mjrodriguez@uach.mx Esteban Sánchez-Chávez esteban@ciad.mx <p>Pfeiffer´s chromatography is based on paper chromatography principles, which could be considered as a useful and cheap alternative for estimating the soil fertility. However, there is a lag in the interpretation of the resulting chromatograms, entangling their use. The objective of this study was to generate prediction models for interpreting the chromatograms obtained from Pfeiffer´s chromatography technique. Physical, chemical, and biological characteristics of soil samples from an apple tree orchard with different agronomic management were evaluated by means of Pfeiffer chromatography and conventional laboratory analyzes. The results were statistically correlated for obtaining the components of the chromatogram with the highest interaction to estimate soil fertility. Eventually, through regression models, numerical patterns were established to estimate and interpret the contents of available P, K+, Cu2+ and organic matter, as well as the categorization to find trends for sand contents, Ca2+, Mg2+, Fe2+, Mn2+ and Zn2+. Results show that, under the conditions in which this research was conducted, the soil fertility can be estimated through Pfeiffer´s chromatography, and that the patterns generated in this study contribute to its interpretation.</p> 2021-03-24T18:52:08+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/853 Ethnoedaphological study of land use types associated with productive chains in the Ejido Santa Cruz Durango 2021-03-17T04:25:13+00:00 Iris del Carmen Morales-Espinoza morales.iris@colpos.mx Carlos Alberto Ortiz-Solorio ortiz@colpos.mx Ma. Del Carmen Gutiérrez-Castorena carmen.gutierrez.castorena@gmail.com Edgar Vladimir Gutiérrez-Castorena edgar.gutierrezcs@uanl.edu.mx <p>The signing of the Treaty Mexico-United States-Canada (T-MEC) is intended to improve regional productive chains to promote the creation of a high number of merchandise and build economies of greater scale. However, on a regional scale, the productive chains have limitations, for example, not appreciating the structure in detail, capacities or articulations between them, which are key to taking the product from its origin to the final market. Ethnoedaphology analyses in a holistic and detailed way the knowledge that producers have of their lands. Therefore, the objective of this research is to determine the types of land use related to agricultural production chains through an ethnoedaphological study. This investigation was performed in the common land Ejido Santa Cruz de Guadalupe, Nombre de Dios, Durango. The producers were interviewed about their lands, management, yields and knowledge of productive chains. For each soil class, a modal profile and its edaphic properties were determined in the field and laboratory for its characterization and scientif ic classif ication with the World Reference Base (WRB). The producers recognized 14 land types, which were integrated into f ive reference groups (Kastañozems, Phaeozems, Calcisols, Solonetz and Regosols). The ejido has 48 types of land use that are described by the variables of major use (livestock, dry farming and irrigation); type of producer (owner or lessee); types of tillage (conventional, vertical or a combination of both); cropping system (mono- and polyculture and crop rotation), and the product obtained. In the ejido 11 crops are managed, of which only maize-silo and barley correspond to 100% of the productive chains, leaving aside other products such as beans and alfalfa. The ethnoedaphological study allows integrating knowledge from the beginning of production through the different types of land use to the f inal market, identifying in detail all the articulations of the productive chains of the study area.</p> 2021-03-12T22:42:39+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/676 Fodder productivity in corn hybrids under different plant densities and fertilization rates 2021-03-18T21:41:08+00:00 Flavio Antonio Rodríguez-Montalvo rodriguez.flavio@inifap.gob.mx Mauro Sierra-Macías sierra.mauro@inifap.gob.mx Alejandro Espinosa-Calderón espinoale@yahoo.com.mx Marcos Ventura Vázquez-Hernández vazquez.marcos@inifap.gob.mx Sabel Barrón-Freyre barron.sabel@inifap.gob.mx Pablo Andrés-Meza pandres272@gmail.com José Luis Del Rosario-Arellano delrosarioarellano@gmail.com <p>Fertilization and plant density are some essential technological components in modern agriculture. The aims of this research was to define the effect of plant density and fertilization rates on fodder productivity of three commercial corn hybrids. In the spring-summer 2017 season, an experiment was established in the Cotaxtla Experimental Field of the National Institute for Forestry, Agriculture and Livestock Research (INIFAP in Spanish), under a completely randomized block design arranged in subdivided plots with three replicates. Three factors were studied, fertilization rates (207-69-60 and 253-69-60), corn hybrids (H-564C, H-567 and HE-3B) and plant densities (62 500, 83 000 and 100 000 plants ha-1). During the study period, the accumulated monthly precipitation was 1003.6 mm and average temperature was 26.7 °C; the maximum temperature occurred in August (28.7 °C) and the minimum in November (25.3 °C) 2017. Duncan’s test (P ≤ 0.05) showed that the fertilization rates integrated by the formula 253‑69‑60 increased green fodder yield, 15.06% more than in the formula 207-69-60. Hybrids H-564C and HE-3B expressed the best green fodder yields with 53 105 and 51 937 kg ha-1, respectively. Increasing plant density (62 500 to 100 000 plants&nbsp;ha‑1) and green fodder yield when high units of N were applied (253-69-60). Likewise, the increase in plant density did not affect the agronomic characteristics of the evaluated hybrids. The commercial H-564C hybrid expressed the highest green and dry fodder yields, followed by the experimental HE-3B hybrid. This last material is a candidate to be released and commercialized for fodder purposes in the tropical area of the state of Veracruz.</p> 2021-03-12T22:55:40+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/745 Groundwater quality for agricultural use in Zacoalco de Torres and Autlan de Navarro, Mexico 2021-03-17T04:25:08+00:00 Oscar Raúl Mancilla-Villa oscar.mancilla@academicos.udg.mx Blanca Noemy Anzaldo-Cortes mimicortes05@gmail.com Rubén Darío Guevara‑Gutiérrez rguevara@cucsur.udg.mx Omar Hernández-Vargas omarhv.irna@gmail.com Carlos Palomera-García cpalomera@cucsur.udg.mx Yerena Figueroa-González oscar.mancilla@academicos.udg.mx Héctor Manuel Ortega-Escobar manueloe@colpos.mx Héctor Flores-Magdaleno hectorfm27@hotmail.com Álvaro Can-Chulim alca1902@gmail.com Elia Cruz-Crespo ccruzc2006@yahoo.com.mx Edgar Iván Sánchez-Bernal edgarivansb@zicatela.umar.mx José Luis Olguín-López olguin@cucsur.udg.mx Isabel Mendoza-Saldivar imendoza@itesa.edu.mx <p>In Mexico, one of the main sources of agricultural&nbsp;irrigation supply is groundwater, irrigating approximately two million hectares of land and also&nbsp;providing 75% of water volume in rural and urban areas nationwide. However, these water resources have been largely affected by pollutants from industrial waste, as well as leaching of chemical substances in agricultural soils. To assess the physicochemical characteristics of groundwater, this study was performed in Zacoalco de Torres and Autlan de Navarro, which are located in areas of the agricultural valley and thus influenced by agricultural and urban activities. Samples were collected in the dry and rainy seasons in 2017. The sampling sites were deep wells and water wheels. In total 48 samples were obtained corresponding to the two stations. In each sample, the following parameters were analyzed: pH, anions and cations, electric conductivity (EC), residual sodium carbonate (RSC), sodium adsorption ratio (SAR), as well as hydrogeochemical classif ication. The underground waters of Zacoalco are mostly chlorinated-magnesium waters and in Autlan bicarbonate-magnesium with medium and low concentrations, so they are recommended for irrigation; with respect to salinity Zacoalco has 40% high salinity waters in dry and 66% medium salinity waters in rains; Autlan has 75% high salinity waters in dry and 75% medium salinity waters, so its use shows moderate restrictions.</p> 2021-03-12T23:13:42+00:00 Copyright (c) 2021 Terra Latinoamericana https://www.terralatinoamericana.org.mx/index.php/terra/article/view/798 Changes in restored soils subject to weathering and their implication in Mexican environmental regulations 2021-03-17T04:25:27+00:00 José del C. Méndez-Moreno mendez_1289@hotmail.com Iliana M. De la Garza-Rodríguez iligarza4@hotmail.com Sonia A. Torres-Sánchez sonia.torres@uaslp.mx Nelly del C. Jiménez-Pérez njimenezp@gmail.com Irma Sánchez-Lombardo irma.sanchez@ujat.mx Sugey López-Martínez sugeylo@hotmail.com Carlos E. Lobato-García carlos.lobato@ujat.mx Carlos M. Morales-Bautista carlos.morales@ujat.mx <p>An overview of current Mexican legislation regarding soil restoration and updating needs is made through the analysis of three case studies located in the southeastern México: a) soil affected by spillage of congenital waters (Zone 1), b) soil contaminated by hydrocarbons (Zone 2) and, c) a site adjacent to urban infrastructure (Zone 3). It was performed a comparative analysis of the soils conditions in the short and long term after the anthropogenic impact and restoration process that were carried out in each studied location. It was found that important properties of the soils do not recover after the weathering process, for instance in Zone 1, DR and DA as well as %Po did not reach equivalent values to the control sample and the soil texture is different even after a long recovery period. For Zone 2, it was detected important variations in the concentration of Ca, Na and K in both the impacted and recovered soils which affect the growth of plantations. In Zone 3, there were found signif icative differences in DA, %Po; %L, %R, %MO and CEC parameters. The current normative considers general aspects, but does not contemplate the actual site situation, there is an information gap due to this, although it was observed achievement of physical and chemical properties for the&nbsp;recovery soil use in each site, it was also noticed that the evaluations do not consider if these properties can change over time due to weather conditions, therefore, they could influence the success of each restoration process in the long term. The information generated can be used to make decisions about government rescue programs for the primary sector or as a starting point in the implementation of Environmental Bases Lines (LBA) for the hydrocarbon sector.</p> 2021-02-12T23:48:45+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/827 Effect of imbibition treatments on the germination of Stenocereus zopilotensis (Cactaceae) native from Guerrero, Mexico 2021-03-17T04:25:24+00:00 Abraham Monteon-Ojeda abraham.monteon@gmail.com Betsabe Piedragil-Ocampo betsabe.piobe@gmail.com Paul García-Escamilla paul_ge@hotmail.com Yuridia Durán-Trujillo duty_1@hotmail.com Teolincacihuatl Romero-Rosales teolinc@hotmail.com <p>The prickly pear cactus “tuna pelona” (Stenocereus zopilotensis), is an endemic cactus species from the state of Guerrero, Mexico, it develops in semi-arid areas and has great ecological importance as it houses and forms part of the diet of multiple species in its niche. There is a constant threat to natural populations of this species due to the overexploitation of seedling collections in the f ield by unregulated trade. In order to design an alternative for the conservation management of these species, the objective of the work was to evaluate treatments for the imbibition of “hairless tuna” seeds to promote germination and the successful establishment of seedlings with economic technologies for the farmers of the area. Fruits of "tuna pelona" (S.&nbsp;zopilotensis) were collected, near the community of Xalitla, municipality of Tepecoacuilco de Trujano, Guerrero; the seeds were stored for 70 and 273 days after collection (dac) at room temperature in order to maintain adequate conditions for the conservation of&nbsp;viability until reaching dormancy. In the stored seeds, the effect of soaking treatments was evaluated: 0, 6, 12, 24 and 12 hours in water plus another treatment that consisted of immersion in a plant-based hormonal stimulant. The germination percentage per treatment was evaluated, it was found that the control treatment (zero hours in water) of seeds stored at 70 dac only obtained 2.4% of germination. The treatment of soaking in water and in the hormonal stimulant both for 6 h presented the highest germination values with 48.6 and 44.4% respectively when using seeds of 273&nbsp;dac at 14 days after the application of the treatments. These results will allow the massive production of seedlings of the species for reforestation and regional marketing purposes.</p> 2021-02-12T23:57:51+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/803 Effect of seed treatment with QuitoMax® on the yield and quality of ESEN and L-43 varieties of tomato seedlings 2021-03-17T04:25:22+00:00 Luis Gustavo-González ggonzalezg@udg.co.cu Irisneisy Paz-Martínez trivas@pg.cibnor.mx Tony Boicet-Fabré tboicetf@udg.co.cu María Caridad Jiménez-Arteaga ejimeneza@udg.co.cu Alejandro Falcón-Rodriguez alfalcon@inca.edu.cu Tomás Rivas-García trivas@pg.cibnor.mx <p>The research work was developed in the basic unit of cooperative production UBPC "Antonio Maceo Grajales" during the 2017-2018 and 2018‑2019 seasons, on a Fluvisol soil, with the objective of evaluating the influence of the QuitoMax® on the seedlings obtained in tomato seedbeds. Two experiments were carried out, in the 2017-2018 season the variety ESEN was evaluated and in the season 2018-2019 the variety L-43, the seeds were soaked in a solution of QuitoMax®, with a concentration of 1 g L-1 during the four hours prior to sowing. Ten polyurethane trays were used for the treated seeds (T1) and another 10 with untreated seeds (T2). At the time of transplantation, the following parameters were evaluated: Plant height (cm), stem thickness (mm), number of leaves, root length (cm) and fresh mass (g). For the statistical analysis of the data from the seedbed, a t-student test was used for a 5% of probability of error, with the statistical package STATISTICA version 8. The results demonstrated the positive incidence of the QuitoMax® about the quality of the seedlings in both varieties.</p> 2021-02-13T00:04:51+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/841 Development and production of cabbage (Brassica oleracea var. Royal vantage) under different osmotic pressures and biofertilized with bacterial consortia 2021-03-17T04:25:20+00:00 Iris Margarita Aguilar-Flores irismagf@gmail.com David Espinosa-Victoria despinos@colpos.mx Moisés Carcaño-Montiel mgcarca@yahoo.com.mx María de las Nieves Rodríguez-Mendoza marinie@colpos.mx <p>The development and production of cabbage (Brassica oleracea var. Royal vantage) in a greenhouse, under different osmotic pressures of the Steiner nutrient solution and biofertlized with bacterial consortiums, were evaluated. A 4 × 3 factorial design was established, where the factors were four levels of osmotic pressure (0.18, 0.36, 0.54 atm and a control without nutrient solution), and two bacterial consortia: Azospirillum brasilense + Acinetobacter calcoaceticus (AA) and Raoultella terrigena + Chromobacterium violaceum (RC), and an uninoculated control. Six repetitions were established for each treatment. Seeds inoculated with the consortium AA had the highest emergence percentage (100%), as well as the highest emergence rate (20.5), compared with the consortium RC and the non-inoculated plants. Inoculation with the consortium AA and the osmotic pressure of 0.54&nbsp;atm produced taller plants (60-65%), and a stem with a larger diameter (35-46%). The weight of the fresh biomass and the accumulation of dry material doubled in the inoculated plants compared to the non-inoculated ones. A higher concentration of K was observed in plants inoculated with AA and RC (20‑35% and 25-45%, respectively) compared to non-inoculated plants. The nitrate concentration in the plants increased between 200-350% and 60-230% with the inoculation of consortia AA and RC, respectively. The P concentration increased between 200-500% with the consortium AA and between 100-400% with the consortium RC. Inoculation with the consortia AA and RC, at osmotic pressure of 0.54 atm, induced the greatest development of the cabbage heads (classif ied as 5 and 4, respectively). It is concluded that cabbage, under moderate mineral fertilization in a greenhouse, responds favorably to the inoculation of plant growth promoting bacteria.</p> 2021-02-13T00:18:34+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/834 Diversity of arbuscular mycorrhizal fungi associated with field-grown zucchini pumpkin (Cucurbita pepo L.) using plastic padding 2021-03-17T04:25:18+00:00 Liliana Lara-Capistrán llara_capistran@hotmail.com Ramón Zulueta-Rodríguez rzulueta36@hotmail.com Juan José Reyes-Pérez jjreyesp1981@gmail.com Bernardo Murillo-Amador bmurillo04@cibnor.mx José Leonardo Ledea-Rodríguez ledea1017@gmail.com Luis Guillermo Hernández-Montiel lhernandez@cibnor.mx <p>Microbial communities have effects on crop growth and productivity. However, these communities can be affected by various agricultural practices. The aim of this work was to determine the diversity of arbuscular mycorrhizal fungi (AMF) associated with the cultivation of zucchini pumpkin established in the f ield under plastic padding. The abundance, richness and index of mycorrhizal diversity in the padded cultivation of zucchini pumpkin were evaluated under three colors (white, black and red) of padding plastic during the summer-fall (S‑F) and winter-spring (W‑S) cycles established with the following treatments: C (control), V (vermicompost), WPP (white plastic padding), WPP+V, RPP (red plastic padding), RPP+V, BPP (black plastic padding) and BPP+V. A randomized experimental block design with 10 replicates was used. The ANOVA showed signif icant differences (P&nbsp;≤ 0.05) in mycorrhizal colonization, abundance and diversity index in both culture cycles. In addition, 21 morphospecies were identif ied in S-A and 12 in W-S. The BPP affected the AMF in all the variables evaluated. Seasonality conditioned mycorrhizal colonization, and the black padding affected the endophyte-host symbiosis, in addition to affecting the mycorrhization, abundance, richness and diversity index of AMF. Knowledge on the diversity of AMFs is important to select the morphospecies with potential as biofertilizers.</p> 2021-02-13T00:36:10+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/544 Economic value of water in the Alfajayucan (100) district of irrigation, Hidalgo 2021-03-17T04:25:16+00:00 Domingo Martínez-Luna dom0301@hotmail.com José S. Mora-Flores saturmf@colpos.mx Adolfo A. Exebio-García adolfoantenor@hotmail.com Oscar A. Arana-Coronado aranaosc@colpos.mx Enrique Arjona-Suárez arjona@colpos.mx <p>Water for human consumption is supplied for different demanded uses: domestic, agriculture and industry. According to what has been reported by FAO and UNESCO, agriculture consumes 69% of water; domestic purposes consume 10% and industry 21%. Given the importance of water in agriculture and crop pattern, knowledge on the optimal allocation and economic value of the resource is required. The objective of our study was to obtain an optimal crop pattern in the Irrigation District 100 (ID 100) Alfajayucan Hidalgo, as well as to estimate the economical price of water under different scenarios. The hypothesis states that the fees paid by farmers in ID 100 do not reflect their true scarcity value. A&nbsp;linear programming model was implemented to maximize the net income of farmers with 17 cyclical and perennial agricultural activities, subject to 57 surface restrictions, water, labor and machinery. The results indicate that the net income of ID 100 would increase by $273 million if the optimal crop pattern is established, compared to that obtained in the 2015‑2016 agricultural cycle. The economical price of the water according to the model was $1.44&nbsp;m-3, much higher than that currently paid (irrigation fees = $0.02&nbsp;m-3), conf irming the existence of a strong subsidy to the water supply. Thus, in light our results, the water fees paid by farmers should increase.</p> 2021-02-13T00:37:43+00:00 Copyright (c) 2021 JOURNAL TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/802 Actinobacteria from avocado rhizosphere: antagonistic activity against Colletotrichum gloeosporioides and Xanthomonas sp. 2021-01-19T20:46:35+00:00 Jesús Rafael Trinidad-Cruz jesus.trinidadcruz@gmail.com Gabriel Rincón-Enríquez grincon@ciatej.mx Zahaed Evangelista-Martínez zevangelista@ciatej.mx Cecilia Guízar-González cguizar@ciatej.mx Jhony Navat Enríquez-Vara jenriquez@ciatej.mx Luis López-Pérez lexquilax@yahoo.com.mx Evangelina Esmeralda Quiñones-Aguilar eqaguilar08@gmail.com <p>Actinobacteria from the rhizosphere of agricultural crops are a potential source of antagonists against phytopathogenic microorganisms. Thus, the objective of this study was to characterize the antagonistic activity in vitro of actinobacteria from the rhizosphere of avocado trees (Persea americana) against Colletotrichum gloeosporioides and Xanthomonas sp. Actinobacteria were isolated from rhizosphere soil samples of avocado trees var. Hass collected from an orchard from Ziracuaretiro, Michoacán. The isolated strains were assessed against C. gloeosporioides and Xanthomonas sp. by means of in vitro confrontation tests. The antagonistic activity was determined by measuring the radius and diameter of the growth inhibition zone of C.&nbsp;gloeosporioides and Xanthomonas sp., respectively. A total of 41 actinobacterial strains were isolated, of which 44% inhibited growth of at least one of the two plant pathogens. Specif ically, 15% of the isolates inhibited growth of C. gloeosporioides, 22% of Xanthomonas sp. and 7% of both phytopathogens. The mycelial growth inhibition radius of C. gloeosporioides fluctuated from 6.6 to 15.5&nbsp;mm, while in Xanthomonas&nbsp;sp., the inhibition zone was from 15.5 to 62.7 mm. These results indicated the importance of rhizosphere actinobacteria as antagonists of phytopathogenic microorganisms, some of which could be used as potential biological control agents against anthracnose and bacterial leaf spot.</p> 2021-01-18T00:00:00+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/759 Tolerance to heavy metals of plants from arid zones 2021-01-19T20:46:56+00:00 Lucila Perales-Aguilar lucilaperales4@gmail.com José Antonio Esquivel-Rivera mc.antonioesquivel@gmail.com Héctor Silos-Espino silosespino@hotmail.com José Cruz Carrillo-Rodríguez jcarrillo_rodriguez@hotmail.com Catarino Perales-Segovia cperales55@hotmail.com <p>In Mexico, arid areas represent more than half of the territory where erosion is due to pollution, so the level of tolerance of representative plant species should be studied to restore or reforest. This study evaluated six species from arid zones – Agave funkiana, A. obscura, A. salmiana of the Asparagaceae family and Opuntia cochenillifera, O. ficus-indica, Pereskia sacharosa of the Cactaceae family. The plants were propagated in vitro to obtain shoots that were established at different cadmium (Cd2+) and lead (Pb2+) concentrations during the rooting stage to determine their tolerance. The Probit Analysis was used to calculate the mean lethal concentration (LC50) at the different doses, which produced different effects in the six species of arid zone plants evaluated in this investigation. The species A. salmiana and P. sacharosa obtained a mortality of 55% with 0.009 mM of Cd and 77% with 0.8 mM for Pb. These concentrations were the highest. Thus, ecotoxicological bioassays are useful for evaluating contaminants, such as heavy metals in tolerant plants as A. obscura, O. cochenillifera, and O. ficus-indica.</p> 2021-01-17T20:37:13+00:00 Copyright (c) 2021 Terra Latinoamericana https://www.terralatinoamericana.org.mx/index.php/terra/article/view/796 Agronomic response of two tomato varieties (Solanum lycopersicum L.) to the application of the biostimulant whit chitosan 2021-01-19T20:46:54+00:00 Tomás Rivas-García trivas@pg.cibnor.mx Luis Gustavo Gonzalez-Gomez ggonzalezg@udg.co.cu Tony Boicet-Fabré tboicetf@udg.co.cu María Caridad Jiménez-Arteaga ejimeneza@udg.co.cu Alejandro Bernardo Falcón-Rodríguez alfalcon@inca.edu.cu Julio César Terrero-Soler jsoler@pg.cibnor.mx <p>Chitosan has properties that promote growth and nutrition of crops. It is a biostimulant that in previous studies it demonstrated activity as growth regulator, germination and vigor promoter of plants, and yield increaser. In this work, it was evaluated the individual or combined effect of the application of chitosan by seed imbibition and foliar administration at the beginning of flowering on the agronomic response (growth, development and yield) of two varieties ESEN and L-43, established in f ield conditions with a block design at random with three replicates. The results show that the combined treatment of chitosan on the seeds in doses of 1 g L-1 and at the beginning of flowering in doses of 300&nbsp;mg ha-1 promotes the evaluated variables associated with yield, and increasing this up to 60.9&nbsp;Mg&nbsp;ha-1 in the ESEN variety and up to 27 Mg&nbsp;ha-1 in the L-43 variety, which represents an increment of 28.5 and 25% respectively, in comparison with the control treatment. It is concluded that the biostimulant chitosan applied as combined treatment during seed imbibition and foliar via at the beginning of flowering has signif icant results improving the variable number of flowers for plants, number of fruits, mass of the fruits and yield for both varieties in comparison with the treatment control, being obtained yield among 47‑60.9&nbsp;Mg ha-1 when applying chitosan for single 42‑43 Mg ha-1 in the treatment control.</p> 2021-01-17T20:43:41+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/587 Land use change model in Carmen-Pajonal-Machona lagoon system, Mexico 2021-01-19T20:46:51+00:00 Rodimiro Ramos-Reyes rrreyes73@hotmail.com Miguel Ángel Palomeque-De la Cruz migueldacbiol@hotmail.com Hector Javier Megia-Vera ing.hector.megia@gmail.com Daniel Pascual-Landeros ing.hector.megia@gmail.com <p>Change in land use is a dominant process with negative effects on the structure and functioning of ecosystems. The coastal area of Tabasco is very important for economic development because of the large coastal wetland areas that flow into the Gulf of Mexico. However, coastal wetlands are strongly altered by the change in land use due to their proximity to urban areas, oil extraction and agricultural activities. They are also severely threatened by climate change and sea level rise. This study analyzed the change in land use in Carmen-Pajonal-Machona lagoon system on Tabasco coast through Land Change Modeler during 2000-2015. A probabilistic-spatial scenario was generated in 2030 through Markov Chains and Cellular Automata, detecting that secondary vegetation, wetlands, and acahuales altogether decreased 14 238&nbsp;hectares from 2000-2015. These changes have affected the reduction of coastal habitats and lead to high flood risks for the population in this area. Additionally the 2030 projection shows alarming values because the ecosystems reflect a loss of 8090 hectares if no change in favor is performed in the paradigm of coastal soil management. Therefore, future trends in land use change on the coast of Tabasco can be mitigated through the implementation of sustainable development policies that involve short- and medium-term planning of the establishment of Territorial Planning programs and the creation of Protected Natural Areas.</p> 2021-01-17T20:50:21+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/774 Impact of climate change on potential evapotranspiration and growing season in Mexico 2021-01-21T17:33:26+00:00 Alejandro Ismael Monterroso-Rivas aimrivas@correo.chapingo.mx Jesús David Gómez-Díaz dgomez@correo.chapingo.mx <p>Potential evapotranspiration (PET) and length of growth period (LGP) are essential indicators of agricultural planning. National and local agendas should consider climate change scenarios and its impact on evapotranspiration. Therefore, the objective of this study was to analyze spatial distribution of PET and LGP in current climate conditions throughout the country, and under a climate change scenario to have suff icient technical elements for recommending adaptation actions for agricultural national production. The monthly PET was estimated from the reference PET (ET0) by the Penman-Monteith method using parameter and monthly average rainfall (R), start and end date, and length of growing period were evaluated. Once this was done, 28 climate change scenarios were studied to def ine the alteration of PET and its effect on LGP in the agricultural areas of the country. PET is expected to increase practically throughout the national territory as a consequence of the general increase in temperature and the decrease in relative humidity. PET classes smaller than 1000 mm per year may decrease, while those greater than 1000 mm may increase on average 20% around the years 2040-2069, and almost 50% towards 2070-2099. When climate change in LGP was considered for each state, three of them (Baja California Sur, Coahuila, and San Luís Potosí) were considered to experience no change concerning current conditions. In the rest of states, the LGP may decrease due to a combination of changes at the beginning and end of the growing period. Cartographic studies allow spatial analysis of the results, which should be integrated into the planning of agricultural water use. At the same time, they make it possible to advance in the design of measures to adapt for climate change with a solid technical support.</p> 2021-01-17T21:01:01+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/792 In vitro establishment of the nematophagous fungus Pochonia chlamydosporia var. catenulata in different soils 2021-01-19T20:46:48+00:00 Wilson Geobel Ceiro-Catasus wceiroc@udg.co.cu Maité Hidalgo-Viltres mhidalgo@udg.co.cu Leopoldo Hidalgo-Díaz lhidalgo@censa.edu.cu Jersys Arévalo-Ortega jersys@censa.edu.cu Milagro García-Bernal milagarciabernal@gmail.com José Manuel Mazón-Suástegui jmazon04@cibnor.mx <p>The edaphic conditions present in agroecosystems can influence the establishment and effectiveness of a microbial control agent for nematodes. For this reason, the objective of the present investigation was proposed to evaluate the in vitro establishment of Pochonia chlamydosporia var. catenulata in Cuban agricultural soils of the Ferralitic, Fluvisol and Brown type. For this, three types of soils were analyzed using the soil membrane technique, evaluating in each one of them the native microbial populations, the mycelial growth and the relative growth of the nematopophagous fungus of interest. A completely randomized design was used and the statistical processing of the data obtained was performed using a factorial ANOVA and linear regression. The results showed that P. chlamydosporia var. catenulata grew and produced chlamydospores in all the edaphic conditions evaluated, however, the greatest growth was registered in Fluvisol and Ferralitic soils compared to Pardo. This suggested that the higher native microbial populations and the acid pH present in the Brown soil, could affect the growth of this fungus. The results obtained conf irm that the nematophagous fungal species P. chlamydosporia var. catenulata has adaptability, persistence and multiplication capacity in different soils and its use is suggested in Fluvisol, Ferralitic and Brown soils, provided they do not present an acid pH ≤ 4.17.</p> 2021-01-17T21:01:52+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/698 Soil quality evaluation: generation and interpretation of indicators 2021-01-19T20:46:46+00:00 Ximena Castillo-Valdez casv.ximena@gmail.com Jorge Dionisio Etchevers-Barra jetchev@colpos.mx Claudia María Isabel Hidalgo-Moreno hidalgo@colpos.mx Arturo Aguirre-Gómez aag@unam.mx <p>Soil management practices alter its properties, especially when the energy inputs to the soil-plant system are less than the outputs, or its resilience is unable to return it to the state prior to the intervention. When the disturbances approach the tolerance limits of the soil system, factors that limit production appear. Changes can be established using quality indicators and indices. These show the direction of change over time. The objective of this work was to evaluate the current soil quality in four agricultural ejidos of Tepeaca, Puebla, Mexico, which have centuries of dedication to agricultural production. The history, the most common cropping patterns and the dominant land classes, defined with the participation of local producers, were investigated. Physical, chemical and biological properties of soils subjected to different management were analyzed and quality indicators were defined. The&nbsp;selection criteria for the sampling sites were the most frequent cultivation patterns as follows: (i) cut flower, (ii) continuous vegetables, and (iii) vegetables with resting period during the season with no rain. The same soils were used without management as reference. The properties selected as indicators were the following: pH, electrical conductivity, soil organic matter, wet aggregate stability, Olsen extractable phosphorus, DTPA extractable iron, and earthworm density. The first four were sensitive to differentiate between undisturbed (uncultivated) soils from cultivated soils. The last four were selected by showing rates of change according to cropping patterns, which indicates the need to promote agronomic management strategies. With these properties, a soil quality index was built that allows to establish the direction of change that soil quality will experience when modifying one or more indicators.</p> 2021-01-17T21:02:38+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/829 Evaluation of the yield, morphological and chemicals characteristics of varieties of purple corn (Zea mays L.) in the region Cajamarca-Peru 2021-01-19T20:46:44+00:00 Melissa Rabanal-Atalaya ct_vistaflorida@inia.gob.pe Alicia Medina-Hoyos amedina@inia.gob.pe <p>Peru has a great diversity of agricultural products due to the variety of climates and geographical diversity, hence it accounts with seven main races of purple corn. Therefore, the objective of our research was to evaluate the yield, and the morphological and chemical characteristics of five varieties of purple corn, which were the following: INIA-601, MMM improved purple corn (experimental variety), UNC‑47, INIA‑615, and PM-581, plus Canteño race, which was used as control. The study was conducted at two altitudinal levels, 2770 m (Llollon) and 3140 m (Llanupacha), both belonging to the District of Ichocan, Province of San Marcos and Region Cajamarca in Peru, during 2017/18 and 2018/19 agricultural campaigns. The agronomic variables and anthocyanin content were evaluated. The results show that the best yield on average was for INIA-601, with 5.3 Mg ha-1 in Llanupacha and with 4.5 Mg ha-1 in Llollon. The varieties with the highest height of the plant and ear were MMM (2.33 and 1.2&nbsp;m) and INIA-601 (2.35 and 1.25 m) in Llollon; whereas in Llanupacha, MMM (1.93 and 0.88 m) and INIA-601 (1.9 and 0.88 m), respectively, obtained the highest values. The INIA-615 variety showed the earliest flowering for females and males in both altitudinal levels, at days101.5 and 93.3 in Llollon and at days 125.6 and 118.3 in Llanupacha, respectively. In addition, this variety obtained the lowest percentage of rot in Llanupacha (2.3%) and in Llollon (5.9%). In addition, the INIA-601 variety was highlighted for having the highest quantity of anthocyanins in both the ear and bracts, presenting (6.7 and 7.5 mg g-1) and (2.9 and 2.5 mg g-1), in Llanupacha and Llollon, respectively.</p> 2021-01-17T21:03:42+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/813 Nitrous oxide (N2O) measurements in managed soil under grazing with dairy cattle 2021-01-19T20:46:42+00:00 Pedro Antonio Núñez-Ramos pnunez58@gmail.com Gregorio García-Lagombra glagombra@gmail.com Joaquín Caridad del Rosario jcaridadr@gmail.com Víctor José Asencio-Cuello vasenciocuello@gmail.com <p>Nitrous oxide (N2O) emissions measurements in livestock systems in the Dominican Republic are a priority for its government. The N2O has been responsible for 5% of total GHG (greenhouse gas) in the last 100 years. In Dominican livestock, various nitrogen fertilizers and amendments are used to increase the productivity these systems. However, if these fertilizers are not properly managed, these could generate N2O emissions. Therefore, our research was carried out with the aim of quantifying N2O emissions from grazing forage with dairy cattle. A Bermuda grass pasture (Cynodon dactylon) from Casa de Alto, Dominican Republic was used. The study was conducted during the period of June – August, 2018. A completely randomized sub-divided plot design was used with three factors, four repetitions and three treatments (urine, urea, and control). Closed-flow PVC chambers were used to obtain gas samples and determine N2O emissions. In addition, climatic factors, nitrogen (N) in urine, soil and grass were recorded. Data were analyzed with the InfoStat statistical software. The N2O emissions averaged the following values: 0.56 mg L-1 for control, 1.02 mg L-1 for urine and 1.18 mg L-1 for urea. The only treatment that showed statistical differences with the control (P&nbsp;&lt;&nbsp;0.05) was urea. Emissions were 5.6, 10.2 and 11.8&nbsp;kg ha-1 for the control, urine and urea, respectively, with high emissions compared to results obtained in other research in the country.</p> 2021-01-17T21:04:27+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/846 Potentialities of oligogalacturonides and chitosaccharides on plant rooting 2021-03-17T04:25:15+00:00 Juan José Reyes-Pérez jjreyesp1981@gmail.com Rommel Arturo Ramos-Remache rramos@uteq.edu.ec Luis Tarquino Llerena-Ramos lllerena@uteq.edu.ec Miguel Ángel Ramírez-Arrebato miguelar@inca.edu.cu Alejandro Bernardo Falcón-Rodríguez alfalcon@inca.edu.cu <p>Oligogalacturonides and chitosaccharides are members of a new class of bioactive substances with plant activity known as oligosaccharins. The&nbsp;application of these substances has direct and indirect benef icial effects on plant rooting processes, which are discussed in this work. These substances have been considered second messengers of some classic plant hormones, such as auxins, cytokines and gibberellins, resulting in their much more specif ic activity in the different organs of plants. Their physicochemical and structural characteristics also have a signif icant influence on their biological activity and especially on rooting processes, both in vitro and in vivo. In our study, we discussed positive effects caused by the application of oligogalacturonides and chitosaccharides in the process of rooting, as well as indirect effects related with the&nbsp;increased interaction with symbiotic soil microorganisms such as rhizobacteria and arbuscular mycorrhizal fungi that improve root growth and function in plants.</p> 2021-02-13T00:44:52+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/808 Analysis of anthocyanins in the purple corn (Zea mays L.) from Peru and its antioxidant properties 2021-01-21T17:34:00+00:00 Melissa Rabanal-Atalaya ct_vistaflorida@inia.gob.pe Alicia Medina-Hoyos amedina@inia.gob.pe <p>The purple corn (Zea mays L.), is an important cereal in Peru, which contains polyphenols, among which include flavonoids, being anthocyanins the most important one. The ear (cob and grain) is made up of 85% grain and 15% cob. Its high content of anthocyanin, mainly as cyanidine-3-glucoside (C3G), makes it act as a powerful natural antioxidant, anti-carcinogenic, and anti-inflammatory, it also helps lower blood pressure and high cholesterol, improves blood circulation and promotes tissue regeneration. Because of these important benefits, it arises the need to understand the mechanism of action of anthocyanins in human health. Therefore, the objective of the present review paper is to describe the chemical structure of anthocyanins, what types and factors affect not only its color but also its stability. In the second part, it was detailed the different races and varieties improved of purple corn in Peru, and the amount of anthocyanins found with the different chemical techniques used. Finally, the different biological activities of anthocyanins are described with emphasis in the most important one as a powerful antioxidant. Finding that the optimal extraction conditions of anthocyanins are with 1 g of sample and 15 mL of water with in agitation constant for 15 min at 90 ºC, highlighting the high antioxidant power in both systems in-vitro and ex-vivo.</p> 2021-01-17T21:14:42+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA https://www.terralatinoamericana.org.mx/index.php/terra/article/view/895 The h index: overvaluation of its use in the assessment of the impact of scientific work in Mexico 2021-01-19T20:46:37+00:00 Alfredo Ortega-Rubio aortega@cibnor.mx Bernardo Murillo-Amador bmurillo04@cibnor.mx Enrique Troyo-Diéguez etroyo04@cibnor.mx Ricardo David Valdez-Cepeda vacrida@gmail.com <p>To judge the impact and relevance of the results of the scientif ic work, the researchers are subjected to evaluation processes that involve records of publications and the corresponding citations. For this purpose, some index has been developed. Among them, the index proposed by Hirsch are considered in most evaluation processes. The analysis developed here concludes that the h-index does not measure the relative contribution of a researcher in publications, especially in those that are generated by groups of between 80 and 700 authors. Likewise, the aforementioned index does not consider book publications, nor the contribution of a researcher in the formation of human resources, nor the formation of scientif ic groups or societies. Nor does the h index value contributions in technological innovation, in the dissemination of scientif ic knowledge. In a relevant way, it must be emphasized that the h index does not take into account the contribution of a specif ic researcher to the establishment of public policies generated through scientif ic research, which can be strategic and of local, regional and even national relevance. Assessing the work of a researcher based primarily on its h-index is not only limited and unfair, but it is severely distorting the priorities of the new generations of scientists in Mexico. Scientists must not forget that we are subsidized with public resources, which leads to not only being widely cited at the international level, but also to contribute to the formation of human resources, to the resolution of local and national problems, to influence the generation of Public Policies and in the social appropriation of knowledge. Therefore, the need to manage a system that considers these aspects is essential in order to evaluate the possible impact of the work of each researcher.</p> 2021-01-17T21:15:29+00:00 Copyright (c) 2021 REVISTA TERRA LATINOAMERICANA