REVISTA TERRA LATINOAMERICANA 2023-06-01T19:22:21+00:00 Dr. Bernardo Murillo Amador 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> Application of compost tea, co-inoculation and inorganic fertilization on Swiss chard plants 2023-05-31T22:29:03+00:00 José Antonio Rodríguez-de la Garza Claudia Nayeli Guerra-Guerra Libia Iris Trejo-Téllez Daniela Alvarado-Camarillo Laura María González-Méndez Alonso Méndez-López Silvia Yudith Martínez-Amador <p>Swiss chard is a horticultural crop with a highly nutritious value. These crops’ production required nutrients, which can be provided through mineral nutrient solutions or biofertilizers. Biofertilizers are products that contain beneficial microorganisms that improve soil quality and that promote plant growth. Additionally, these microorganisms carry out nitrogen fixation and phosphate solubilization. The present work assessed the application of compost tea, co-inoculation (Azospirillum and Glomus), and inorganic fertilizer over the growth (roots, stem, and leaves) and nutrient content in Swiss chard (Beta vulgaris var. Forhook Giant) plants. The present work was carried out in a greenhouse using a randomized complete block design. Swiss chard plants treated with compost tea + inorganic fertilization (CTIF) accumulated more root and stem dry weight (4.06 and 8.10 g respectively), and, on the other hand, the leaf dry weight increased under three treatments: inorganic fertilization (IF), compost tea + co-inoculation (CTCi) and CTIF (12.5, 9.22 and 10.5 g respectively). Leaf area was greater in the IF and CTIF treatments. In Control (C) P and Mg content were higher; CTCi treatment increased the N, K, and Mn content; the co-inoculation (Ci) treatment increased Cu content as well as CTIF treatment increased the Ca, Fe, Zn, and B contents and in a lesser extent also the P, Mg, Cu, and Mn contents. The biomass partitioning coef ficient indicates that in six samples (from a total of seven samples), most of the photosynthates (PS) were used by the plants to form new leaves or to increase the size of the leaves. If an alternative method of fertilization is desired, it is recommended that a combination of biofertilizer and inorganic fertilization should be used, such as, the combination of compost tea and mineral solution that increased the production and the concentration of nutrients in the Swiss chard crop.</p> 2023-05-31T22:29:03+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Ef fect of rhizobacteria isolated from Suaeda sp. in the growth of Arabidopsis thaliana and Solanum lycopersicum L. (Sahariana) 2023-05-31T22:28:16+00:00 Jessica Lizbeth Coria-Arellano Jorge Sáenz-Mata Manuel Fortis-Hernández Miguel Ángel Gallegos-Robles <p>The rhizosphere of the great diversity of plants is a complex ecosystem that houses thousands of rhizobacteria that promote plant growth. In the current investigation, three bacteria were isolated from the root of Suaeda sp., which were evaluated to determine the ef fect of their inoculation on Arabidopsis thaliana at distances of 2 and 5 cm and in divided boxes. In the 2 cm test, we noticed that Endo10(7) and Endo10(5) stimulated the plants more than the control, while the proximity to Ecto10(6) caused them to wilt and die. However, at 5 cm, the bacterium that most promoted the development of Arabidopsis was Ecto10(6). In the divided box test, all three bacteria showed the ability to promote growth. In addition, a shade mesh assay was carried out with the inoculation of the bacteria in Solanum lycopersicum L. (Sahariana) and it was found that the promoting ef fect was also observed in the germination and growth of tomato plants. Tests were conducted to determine its ability to produce IAA, siderophores, and solubilize phosphates. Through molecular techniques it was confirmed: the identity of Ecto10(6), Endo10(7), and Endo10(5) as Aneurinibacillus migulanus, Staphylococcus sp. and Bacillus cereus, respectively. Our results provide the rationale for suggesting that these rhizobacteria may increase the growth and development of Arabidopsis thaliana and Solanum lycopersicum.</p> 2023-05-31T22:28:16+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Morphological and physiological responses of Coccoloba uvifera (L.) L. seedlings of dif ferent origin to salt stress 2023-05-04T17:30:25+00:00 Mijail Mijares Bullaín-Galardis Raúl Campos-Posada Gloria Campos-Posada Bettina Eichler- Löbermann Ludovic Pruneau Amadou Bâ Raúl López-Sánchez <p>The salinity of soils and water for irrigation is a limitation that influences the productivity of crops that has increased worldwide and af fects the morphology and physiology of plants since it causes osmotic stress and ionic toxicity and impairs the absorption of water and nutrients. The ef fect of salt stress on some morphological and physiological traits in Coccoloba uvifera (L.) L. (sea grape) seedlings from dif ferent origins was evaluated and the traits whose behavior under salt stress could be used as an ef fective criterion of tolerance to salinity were determined. A completely randomized design experiment with ten repetitions was performed. The factors under study were salinity (0, 5, 15, and 25 dS m-1), which was maintained for a period of sixteen weeks, and the second factor was the origin of the plant material. The salinity level and the seedlings’ origin significantly influenced the morphological and physiological variables controlled. However, it is necessary to carry out in situ experiments to obtain more information related to the mechanisms used by sea grape to tolerate salinity conditions, because in the consulted sources no research focused on evaluating the ef fect of salinity and the origin on the morphology and physiology of C. uvifera seedlings in Cuba has been found. The results of the research provide preliminary information to understand the negative ef fect of salt stress on this type of plant. The behavior of some controlled traits under salt stress can be used as an ef fective criterion of tolerance to salinity.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Soil fertility and nutrition in cacao cultivation (Theobroma cacao L.) in three soils of Tabasco, Mexico 2023-05-01T22:07:24+00:00 Sandra Patricia Francisco-Santiago David Jesús Palma-López Rufo Sánchez-Hernández José Jesús Obrador-Olán Pedro García-Alamilla <p>Cocoa is a traditional crop in southern Mexico, although its productivity is low due to edaphic and nutritional limitations. Hence, the aim of our research was to diagnose edaphic fertility and the nutritional content of cacao plantations in the main groups of cultivated soils in La Chontalpa, the main cocoa production area of Tabasco state, to identify the edaphic and nutritional variables that restrict crop productivity. Through the analysis of satellite images, sampling sites were selected in representative soils of the study area and the coordinates were geopositioned to locate them. Soil profiles were described to classify the soils of the sampling sites. Soil samples were collected at depths of 0-10, 10-30 and 30-50 cm, to determine variables of soil fertility. In producer trees, foliar samples were collected to determine the concentrations of macronutrients. The results indicate that the plantations are cultivated on Vertisols, Cambisols and Fluvisols, which do not show restrictions in most of the edaphic properties. However, due to the low C/N ratio (&lt; 12) of the soils, there is a decrease in the OM and N contents, which are added to a K deficit, causing low concentrations of both macronutrients in the foliage of the plants. In conclusion, the main edaphic restrictions that can af fect cocoa cultivation in La Chontalpa are the rapid loss of OM and a deficit of N and K in the soil, which cause low concentrations of both nutrients in the foliage of the trees.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Role of Bacillus subtilis and phosphorus doses on macronutrient concentration, partitioning and uptake of common bean 2023-05-01T22:07:43+00:00 Jesús del Rosario Ruelas-Islas Luis A. Peinado-Fuentes Celia S. Romero-Félix Cándido Mendoza-Pérez Hernán Celaya-Michel Pablo Preciado-Rangel Quintín A. Ayala-Armenta Fidel Núñez-Ramírez <p>Knowledge on macronutrient uptake and distribution is highly relevant in fertilization management programs of common bean crop (Phaseolus vulgaris L.). In this regard, the use of plant growth promoting rhizobacteria (PGPR) in combination with phosphorus fertilization could exert a synergistic ef fect and potentiate the process of uptake and distribution of nutrients on this crop. A field experiment was established to investigate the response of the common bean crop to four phosphorus (P) doses, (0, 25, 50, 100 kg ha-1 P2O5) and the strain Bacillus subtilis Q11 (Bs) (seed inoculation and a control without inoculation) on macronutrient concentration, distribution and accumulation. The experiment was arranged under a split plot in a randomized complete block design with three replicates. According to our results, the P doses and the inoculation process af fected biomass accumulation individually. The highest biomass accumulation was obtained with P doses &gt;50 kg ha‑1; whereas inoculation with Bs produced higher biomass compared to the control. The interaction P × Bs af fected significantly the concentration of nitrogen, phosphorus, potassium, calcium and magnesium in dif ferent plant organs in all stages of growth, except for pods during the grain filling stage. The nutrient uptake pattern exhibited a sigmoid curve and was individually modified by the P doses and Bs inoculation. The 50 kg ha-1 P dose increased macronutrient accumulation, especially during grain filling; while the inoculation with Bs enhanced the uptake process during grain filling and physiological maturity stages. In conclusion, combining Bs and P doses inflicts positive ef fects over the modification of concentration, uptake and macronutrient accumulation in common bean crop.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Oligogalacturonide dose optimization on the vegetative propagation of two cocoa clones (Theobroma cacao L.) under controlled conditions in the nursery 2023-04-04T16:52:34+00:00 Juan José Reyes-Pérez Luis Tarquino Llerena-Ramos Juan Antonio Torres-Rodríguez Luis Guillermo Hernández-Montiel <p>The low ef ficiency of cocoa vegetative propagation from cuttings requires the use of rooting agents. This situation motivated a study whose objective is to optimize the oligogalacturonide dose on the vegetative propagation of two cocoa clones under controlled conditions in the nursery. The source of oligogalacturonides was provided in doses: 0, 10, 50 and 100 mg L-1 compared to the chemical rooting (composed of: 7% nitrogen, 45% phosphorus, 5% potassium, 0.1% boron, 3% metabolic activators and 10% marine algae), which was applied by immersion at the base of the cutting. The clones tested were CCN-51 and EET-801. The evaluated variables were: number of leaves and roots, radical fraction, fresh biomass of leaves and roots, dry biomass of leaves, roots, and stem and index of regenerated plants. The results indicated that the doses of 50 and 100 mg L-1 showed the greatest ef fects on the number of leaves (NH), radical fraction (FR), dry biomass of the leaf (DSB) and stem (DST). Clone CCN-51 showed higher NH, FR, BSH and BST than EET-801 (P &lt; 0.05). In number of roots (NR), fresh root biomass (BFR), dry root biomass (DRB), fresh leaf biomass (BFH) and the index of regenerated plants (IPR), the clones were the same. The IPR had a positive correlation with the other variables (P &lt; 0.05). Using 85 mg L-1 of chemical rooting an IPR of 49.1% can be achieved. The IPR can be predicted based on the variables BFR and BFH with R2 = 0.96.</p> 2023-04-01T04:24:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Physiological and genetic analysis of a mapping population responsiveness to plant growth-promoting Azospirillum in wheat 2023-04-04T16:52:37+00:00 Thelma Castellanos-Cervantes Jose Luis Diaz de León Jie Ling Marion Röder <p>Azospirillum brasilense is a plant growth-promoting rhizobacteria (PGPR) with the potential of being employed as an inoculant to decrease the use of chemical fertilizers. We investigated the ef fect of A. brasilense inoculation on a doubled haploid population derived from Opata / WSHD67.2(257) cross and detected Quantitative Trait Loci (QTL) for seven agronomic traits. The population was segregated, concerning their response to inoculation, into three subgroups: neutral, positive, and negative in a proportion of 60:25:15. A total of 18 major QTL and 83 minor QTL controlled the expression of measured traits. Nineteen QTL showed pleiotropic characteristics; chromosomes 5A, 7A, 7B, and 7D were distinguished as those with QTL controlling four of the seven phenotypes measured. The sequences of nearest markers to major QTL detected synteny to rice sequences that codified for at least 38 candidate genes described and discussed as a first step to understanding the interaction of wheat with A. brasilense.</p> 2023-04-01T04:15:23+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Ef fect of native microorganism ef ficacy and compost in three altitudinal zones on quinoa crop (Chenopodium quinoa) variety INIA 415-Pasankalla 2023-04-24T15:00:04+00:00 Miguel Galecio-Julca María Neira-Ojeda Roger Chanduvi-García Ricardo Peña-Castillo Luis Armando Álvarez-Bernaola Carlos Granda-Wong David Lindo-Seminario Elizabeth Saavedra-Alberca Javier Javier-Alva Davies Arturo Morales-Pizarro <p>Organic fertilizers are a sustainable alternative to conventional fertilizers that cause contamination of natural resources. The objective of this study is to determine the ef ficacy of native microorganisms (ENM) and compost on yield and profitability on the cultivation of quinoa variety INIA 415-Pasankalla in three altitudinal levels (Faical 1935 m altitude, Lagunas Amarillas 2328 m altitude and Cascapampa 2995&nbsp;m altitude). Five treatments were evaluated: T0 (control), T1 (MEN 2.5%), T2 (MEN 5.0%), T3 (MEN 2.5%+0.9 kg compost m-1) and T4 (MEN 5.0%+1.8 kg compost&nbsp;m-1), considering: PA (plant height), RHa (yield per hectare), RPa (yield plant-1), PP (panicle weight), PMG (thousand kernel weight) and DT (stem diameter). In addition, the benefit/cost per treatment was analyzed. A principal component analysis (PCA), three-way ANOVA comparison and correlation analysis were performed. The PCA yielded two components (C1 and C2) explaining 97.20% of the variability of the study. Component 1 (78.46%) explained the greatest variability and grouped the variables: G-I (AP, DT), G-II (RHa, Rpa, PP). Treatments T4 and T3 showed the best results in relation to altitude: Lagunas Amarillas-T4 with G-I and Cascapampa-T4 with G-II showed the highest study values. However, Cascapampa-T2 was the most profitable (b/c= 5,68). The combined mixture of organic inputs made from local raw materials and applied in foliar form, and the soils present in T4, improved the yields and profitability of the quinoa crop in relation to altitude.</p> 2023-04-01T04:07:32+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA "Assessment of the soil quality of Tabasco, Mexico using conventional methods, near-infrared spectroscopy and chemometrics 2023-04-04T16:52:44+00:00 Alex Ricardo Ramírez-García Armando Guerrero-Peña Joel Zavala-Cruz Eustolia García-López Rufo Sánchez-Hernández Joaquín Alberto Rincón-Ramírez <p>A retrospective–prospective research was carried out to establish a soil quality index (SQI) of Los Rios region (RR), Tabasco, Mexico, and its modeling with the near infrared technology (NIR) and chemometrics. The SQI was determined with the OM&nbsp;/&nbsp;(clay + silt) relationship to evaluate the Cambisol soils of RR. The OM percentage and the SQI were compared to define the best soil quality qualifier. Based on the SQI, 58% of the soils in RR exhibit degradation, while only 14% indicates a low concentration of OM. Therefore, we conclude that the SQI is more sensitive to quantify soil degradation compared to the evaluation based on OM. A sustainable soil management program and soil practices adapted to local environmental, social and economic conditions are recommended to increase OM and improve SQI. With the SQI, a classification model was established using near-infrared spectroscopy and chemometrics. The spectra of each soil sample were recorded and through chemometric interpretation, it was shown that it is possible to conduct a partial least squares discriminant analysis model (PLS-DA) to predict the SQI. The model meets all statistical qualifiers and correctly predicts the SQI in 100% of cases. We conclude that the NIR technology provides suf ficient information to predict the SQI with the advantage of eliminating the consumption of reagents, no laboratory waste is generated, the analysis time is reduced to minutes, and the sample under study is not destroyed. In addition, the procedure is simple as it consists of drying, grinding and sieving the soil samples to assess the structural quality of the soil.</p> 2023-04-01T03:41:43+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Influence of four concentrations of Steiner solution on nutrients in soil solution and productivity in tomato (Solanum lycopersicum L.) 2023-04-04T16:52:46+00:00 Felicito Ausencio Díaz-Vázquez Marcelino Cabrera-De la Fuente Adalberto Benavides-Mendoza Valentín Robledo-Torres Antonio Juárez-Maldonado Álvaro García-León Alberto Sandoval-Rangel <p>The development and productivity of agricultural crops is directly related to the nutritional supply they receive. The hypothesis of this trial is that the concentration of ions measured in the soil solution allows evaluating the ef ficiency of the nutritional management and its ef fect on the crop – the concentration of ions are conditioned by the mineral supply and the ion exchange processes of the soil. Thus, the objective of the experiment is to measure the ef fect of the continuous application of four nutrient solution concentrations on the concentration of ions in the soil solution and the tomato crop response under greenhouse conditions. The trial was established in calcareous soil under a complete randomized block design with three replications, with indeterminate tomato plants. The treatments were four concentrations of a Steiner solution modified for tomato cultivation: (1) 50, (2) 75, (3) 100 and (4) 125% applied continuously by fertigation. In each treatment the soil solution was extracted, and the concentration of NO3-, K+ and Ca+2 ions, pH and electrical conductivity were measured for 18 weeks at the same time the crop response was measured. The concentration of the nutrient solution applied constantly to the tomato crop has a direct relationship with the availability of nutrients. The nutrient solution at 125% generated better growth, physiology, commercial quality and agronomic yield. Calcium was the only element that was detected in suf ficient levels in the soil solution from a concentration of 50% in the nutrient solution because of its high original availability in the soil.</p> 2023-03-01T05:21:02+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Hydrological modeling with the SWAT model using dif ferent spatial distributions of soil type in the Mixteco River Basin 2023-04-04T16:52:50+00:00 Gerardo Colín-García Enrique Palacios-Vélez Demetrio Salvador Fernández-Reynoso Adolfo López-Pérez Héctor Flores-Magdaleno Roberto Ascencio-Hernández Enrique Inoscencio Canales-Islas <p>The Mixteco River basin is located in the state of Oaxaca, Mexico and comprises a total area of 6 559.20 km2, which shows a strong degradation of its natural resources, derived mainly from anthropic actions associated with poor management of its natural resources. Thus, the goal of this research is to evaluate the runof f behavior with the SWAT (Soil and Water Assessment Tool) model in the Mixteco River basin using the soil spatial distribution from INEGI (Instituto Nacional de Estadística y Geografía) and that obtained through technique of DSM (Digital Soil Mapping) technique. The modeling with INEGI (ModINEGI) corresponds to the soil map of the series II scale 1:250 000, and the modeling with DSM (ModDSM) was obtained from the environmental covariates. The SWAT model performance evaluation indicators during the calibration phase were R2 = 0.88 and NSE = 0.87 for ModDSM and R2&nbsp;= 0.85 and NSE = 0.85 for ModINEGI. However, during the validation period, the ModDSM results (R2 = 0.83 and NSE = 0.81) were better than those of ModINEGI (R2 = 0.83 and NSE = 0.61). Therefore, the results indicate that the spatial variation of the soil types obtained through the DSM technique in combination with the vegetation cover and the distribution of slopes at the basin level, allow the SWAT model to simulate the adequate surface runof f behavior.</p> 2023-03-01T05:09:40+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Total Nitrogen in forage corn (Zea mays L.) estimated by satellite Sentinel-2 spectral indices 2023-04-04T16:52:52+00:00 Magali J. López-Calderón Juan Estrada-Ávalos Aldo R. Martínez-Sifuentes Ramón Trucíos-Caciano Enrique Miguel-Valle <p>Nitrogen is the most important nutrient for forage crops because of its contribution in various biochemical reactions in the dif ferent phenological stages of the plant. The main aim of this study is to develop a multiple linear regression model to estimate total nitrogen (Nt) in corn plants using spectral indexes. The percentage of total nitrogen (Nt) was determined through three plant samplings in four experimental plots. The estimation model was obtained to process the Sentinel-2 satellite images according to the plant sampling dates; 13 spectral indexes were calculated and the association between nitrogen and the reflectance values was analyzed by the principal component analysis (ACP), correlation matrix, and dendrogram. The indexes with the highest relationship were MCARI / OSAVI, TCARI / OSAVI, MCARI / OSAVI RE and TCARI / OSAVI RE, explaining more than 50% of the variability of the proposed model and a MSE of 0.12. This study indicates that the estimation obtained from Sentinel-2 spectral indexes images has great potential to determine nitrogen in crops. However, for future research, Nt estimation models should be obtained for each phenological crop stage.</p> 2023-03-01T05:02:47+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Edaphological characterization in a blue agave (Agave tequilana Weber) cultivation in Tonaya and Tuxcacuesco, Jalisco, Mexico 2023-02-08T21:48:30+00:00 Blanca Elizabeth Fregoso-Zamorano Oscar Raúl Mancilla-Villa Rubén Darío Guevara-Gutiérrez Arturo Moreno-Hernández Pedro Figueroa-Bautista Álvaro Can-Chulim Omar Hernández-Vargas Elia Cruz-Crespo Héctor Manuel Ortega-Escobar Abdul Khalil Gardezi Víctor Manuel Villalvazo-López <p>The cultivation of blue agave has economic importance in the state of Jalisco as it generates employment, being the main economic source in several municipalities such as Tonaya and Tuxcacuesco. However, at present, the edaphological status of the soils is unknown and there is limited knowledge on the factors that regulate crop growth, which limits the determination of optimal crop yields. In this sense, the aim of our research was to evaluate the state of fertility of the soils cultivated with blue agave in plots with different characteristics (virgin and with several planting cycles), as well as to diagnose their status in the Tonaya and Tuxcacuesco municipalities in order to suggest more efficient management and nutrition practices. After analyses in the laboratory, the results show that the soils presented a mean pH value of 7.7, the mean concentration of organic matter was 2.19%. Overall deficiencies of nitrogen, phosphorus and potassium were found, thus, the soils were classified in the low‑to‑poor category in terms of nutritional content. Moreover, there were no significant differences between the plots evaluated, organic matter content and nutrients. We recommend the use of organic fertilizers and bean/corn/agave polyculture when agricultural and economic resources are sufficient.</p> 2023-01-31T21:54:54+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Bibliometric study on biofertilizers in Mexico during the period 2015-2020 2023-02-08T21:48:34+00:00 Andrés Eduardo Coutino-Puchuli Maida Daylin Peña-Borrego Zoe Tamar Infante-Jimenez <p>We characterized the trend of scientific research on biofertilizers in Mexico based on publications of national and foreign scientific journals during the 2015-2020 period. Our study consisted on the interpretation of research articles (in English and Spanish) published in the following scientific databases: Ebsco, Elsevier, Springer, Scielo, Wiley and Redalyc, for the analysis of bibliometric indicators. Productivity was determined by year, authors, journals, institutions, and collaborations between countries and Mexican states, on issues related to the use of microorganisms by agricultural crop, biofertilizer brands, and econometric variables and indicators. Within the evaluated period, a total of 115 research articles were published, with an annual average of 19 research articles. The most productive year was 2020, with 40 research articles. The authors with the greatest leadership in publications were Arturo Díaz Franco Santacruz and Cid Aguilar Carpio. The scientific journals that published the greatest number of these research articles were Terra Latinoamericana and Revista Mexicana de Ciencias Agrícolas. The main Mexican institutions performing the research were the National Institute of Forestry, Agriculture and Livestock Research (INIFAP) and the Postgraduate College. The United States of America is the country that collaborated the most with Mexican states (five states). Research in corn, varieties of chili, tomato, wheat and sorghum prevailed, being present in more than six research articles. Out of 33 brands of biofertilizers analyzed during the period, Micorriza INIFAP® was applied in more than 27% of the crops that used commercial biofertilizers. The most used microorganisms belonged to the genera Glomus, Pseudomonas, Bacillus and Azospirillum sp. Most of the research papers on biofertilizers are developed in the areas of agronomy, biology and environmental sciences, specifically in studies treating certain agricultural crop, while there are only few studies in the area of administration or marketing.</p> 2023-01-31T21:41:13+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA El Population density and fertilization ef fect on water productivity and yield of corn hybrids in the Mexico Valley 2023-02-08T21:48:44+00:00 Homero Alonso-Sánchez Margarita Tadeo-Robledo Alejandro Espinosa-Calderón Job Zaragoza-Esparza Consuelo López-López Benjamín Zamudio-González Alan Monter-Santillán Antonio Turrent-Fernández Israel Arteaga-Escamilla Karina Mora-García <p>Food insuf ficiency in corn and water and fertilizer crisis worldwide demand ef ficiency in the use of resources, increasing or conserving production. Thus, the objective of this research is to explore the response of four white maize hybrids released for valles Altos in two environments considering two population densities, two doses of fertilization and an unfertilized control group. Hybrids were evaluated in a factorial arrangement in Cuautitlan (FESC-UNAM) and Texcoco (CEVAMEX), Mexico State, at two planting densities (D1 = 75,000; D2 = 90,000 plants ha-1) with three fertilization treatments (F1 = 160-80-00, F2 = 120-40-00, F3 = 00-00-00). The completely randomized block design experiment was made up of the treatments and the combination of the factors 2×4×2×3 established in three repetitions. The means were compared with Tukey’s test (P &lt; 0.05). In FESC-UNAM with less total water, the result of grain yield and water productivity was 5.96 Mg ha-1 and 1.29&nbsp;kg&nbsp;m-3 in CEVAMEX 4.76 Mg ha-1 and 0.5 kg m-3; the Atziri Puma hybrid stood out with 6.52&nbsp;Mg&nbsp;ha-1 and 1.09 kg m-3. No significant ef fect of planting density was observed and D1 resulted with 5.32 Mg ha-1 and 0.9 kg m-3 versus D2 with 5.40 Mg ha-1 and 0.9&nbsp;kg m-3. In fertilization F1 was statistically higher with 5.64 Mg ha-1 and 0.94 kg&nbsp;m-3. Nevertheless, no dif ference was observed between F2 (5.24 Mg ha-1 and 0.88 kg&nbsp;m-3) and the control F3 (5.19 Mg ha-1 and 0.87 kg m-3), which showed the interaction of the environments with hybrids, of which Atziri Puma stood out at FESC-UNAM (7.3&nbsp;Mg&nbsp;ha-1 and 1.58 kg m-3). The FESC-UNAM site has productive potential under rainfed conditions with the Puma and INIFAP hybrids.</p> 2023-01-31T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Effect of tezontle particle diameter in tomato (Solanum lycopersicum L.), cucumber (Cucumis sativus L.) and lettuce (Lactuca sativa L.) in aquaponics 2023-02-08T21:48:36+00:00 Andrés Valenzuela-Antelo Manuel Sandoval-Villa Juan J. Almaraz-Suárez Gabriel Alcántar-González Rafael Bórquez-López <p>Aquaponics is a complex food production system where fish and vegetables are produced simultaneously. Microorganisms, fish and plants participate in it; it is a complex system where conditions conducive to fish may not be suitable for microorganisms and plants. The diameter of the substrate particles for plant support and space for microorganism colonies can be a determining factor in aquaponics. This research investigates the particle size of tezontle, a porous red volcanic gravel that is used in Mexico for hydroponics and that here it is hypothesized that there is a particle size of this material that favors the growth and yield of plants in aquaponics.&nbsp;The model consisted of the use of 12 containers of 120 L as ponds for fish, and 12 tubs of 240 L for the substrate and a 120 L/min air pump to supply auxiliary oxygenation to the ponds. Three crops were established in each tub: tomato, cucumber, and lettuce. These cultures were transplanted in 3 tezontle diameters: particle diameter less than 1 cm (Æ&lt;1), greater than 5 cm (Æ&gt;5) and 50:50 % (v:v) mixture of both diameters (&lt;1:&gt;5), which constituted the substrate particle diameter treatments. There was no effect of substrate particle diameter on height, stem diameter, and SPAD readings in tomato, cucumber or lettuce plants. Regarding the yield and quality of tomato fruits (firmness, titratable acidity and ˚Brix) there were also no effects of the particle diameter of the substrate. There was also no effect of treatments on the morphological and quality variables of cucumber fruits. In the final fresh weight of lettuce, the treatment with substrate with diameter &lt;1 cm was statistically superior to diameter &gt;5 cm with averages of 89.87 g and 50.12 g respectively.&nbsp;Particle diameter does not affect the yield or quality of established crops, however, in practical terms the fine substrate &lt; 1 cm is recommended because it has greater moisture retention capacity and greater surface area for bacteria to colonize the environment, and promote higher plant growth and fruit quality in aquaponics. The fine substrate acts as a filter to retain suspended solids and prevents clogging of the system, and improves water quality and generates better living conditions for fish.</p> 2023-01-31T21:36:30+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Digital soil mapping with regression-Kriging and data from remote sensing 2023-02-15T21:52:46+00:00 Francisco Estrada-Godoy Gustavo Cruz-Cárdenas Salvador Ochoa-Estrada José Teodoro Silva <p>The use of digital soil mapping allows obtaining quantitative information on soil distribution and functioning to provide alternatives for their management. The objective of this research is to perform the spatial prediction of soil properties through regression-kriging and serve as a basis for taking the necessary measures for a sustainable use of the resource. The study area is located in the wetland Cienaga de Chapala portion of Michoacán, Mexico. Soil sampling was systematic. In the laboratory, electrical conductivity, organic carbon, soluble cations calcium, potassium, magnesium, sodium (Ca, K, Mg, Na), total nitrogen and pH were determined for each soil sample. The dependent variables were total nitrogen, electrical conductivity, organic carbon and pH. The independent variables are the Landsat 8 satellite bands. Regression-kriging was applied for spatial prediction. The experimental semivariogram fit with theoretical models was consistent for the four soil properties, because it was a systematic sampling design and the sample size was 297 points. The root mean square error of the electrical conductivity spatial prediction was 4 because it showed a coefficient of variation of 355. Soils are considered having from low to very low total nitrogen content (&lt;0.15%). At least 30% of the soils have salinity problems because their electrical conductivity is greater than 1.1 dS m-1. Organic carbon contents are considered medium to high (&gt;0.6%). The pH of the soils is moderately alkaline.</p> 2023-01-31T20:33:05+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Land use change by the NAICM construction in Texcoco, Mexico State 2023-02-08T21:48:41+00:00 Arely Romero-Padilla Martín Hernández-Juárez <p>Mexico’s New International Airport megaproject was announced for the first time in 2001 and canceled in 2019; however, most of its construction progress took place during 2012-2018. With its announcement and cancellation there was a land use change and speculation regarding the land value. This study evaluates the impact that the airport construction and cancellation had over land use change in the municipality of Texcoco and neighboring municipalities in Mexico State, and the perception of key players concerning its effects. High-resolution images from the Sentinel-2 satellite were processed for the years 2016 to 2021. Geographic information systems were used to carry out a supervised classification with spectral indices and generate thematic maps of land use with four classes: bare soil, vegetated soil, urban land and water bodies. Interviews were applied to key players for a qualitative analysis of the appreciation of changes and effects derived from the airport project. Results show a higher growth rate of urban land from 2016 to 2017, mainly close to the airport building, replacing mostly bare soil. The airport caused discontent in the population by its environmental effects and social consequences, such as problems due to freight vehicles traffic. As a result of the airport cancellation, there is bare ground caused by mine exploitation and vehicular insecurity due to incomplete roads.</p> 2023-01-31T20:22:35+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Editorial - Alternativas del uso y manejo del suelo del agua y la vegetación 2023-05-30T02:26:22+00:00 Verónica Ortega-Baranda <p>El presente número integra manuscritos implementados por científicos investigadores de la Universidad del Mar, campus Puerto Escondido, así como de instituciones de relevancia nacional como el Colegio de Postgraduados, la Universidad Autónoma de Nayarit y la Universidad de Guadalajara. Las contribuciones que se presentan, muestran el interés de los científicos en el estudio de la calidad química de las aguas superficiales de algunas cuencas de importancia nacional, la salinidad de los suelos, la evaluación de la tolerancia a sales de algunos pastos costeros como alternativa para la producción de forraje, las características fenológicas y crecimiento de especies nativas en conservación de la selva baja caducifolia, alternativas de alimentación de ganado con especies vegetales forrajeras, así como, la disponibilidad de establecer manchones arbóreos en suelos salinos del Ex Lago de Texcoco, México. Estas contribuciones integran datos experimentales de campo que muestran conclusiones validas sobre la respuesta de los fenómenos. De igual manera, proponen alternativas de uso y manejo del suelo del agua y la vegetación que persiguen la conservación de los ecosistemas y la generación del bienestar socioeconómico de las comunidades rurales que integran las áreas de estudio. Esperando lograr la inquietud cognoscitiva del público en general.</p> <p>Con especial reconocimiento al Dr. Edgar Iván Sánchez Bernal (1963 - 2022) por su incansable estudio a favor de los suelos de la costa de Oaxaca.</p> 2023-05-29T00:00:00+00:00 Copyright (c) 2023 Characterization of the salinity in soils of the San Pedro River floodplain, Nayarit, Mexico 2023-06-01T19:22:16+00:00 Héctor Manuel Ortega-Escobar Oscar Germán Martínez-Rodríguez Álvaro Can-Chulim Elia Cruz-Crespo José Irán Bojórquez-Serrano Juan Diego García-Paredes Edgar Iván Sánchez-Bernal Alberto Madueño-Molina Oscar Raúl Mancilla-Villa <p>The floodplain of the San Pedro River, a fluvial-delta formation, is one of the coastal areas affected by marine intrusion during the last glaciation. In this region, agriculture is the main economic activity; however, intensive agricultural practices, the geological past, current interactions with the marine system and the transport of salts through sediments and water make this area susceptible to soil salinization. To characterize the salinity of the agricultural area of the San Pedro River floodplain, two soil samplings were carried out at 91 sites over a period of two years. Samples were taken from depths of 0.0 to 0.3 m and from 0.0 to 0.1 m to depths of 1 m and 3 m. Fifty groundwater samples were collected. Saturation extracts were obtained (1: θsat) from the soil samples. For the soil and groundwater extracts, the pH, EC, and major cations and anions were determined, the sodium adsorption ratio was calculated in the original and adjusted formulations (SARor and SARadj), and the exchangeable sodium percentage (ESP) was ascertained. The pH, EC and SARor of the groundwater ranged from 6.94 to 8.37, 199 to 4660 µS cm-1 and 0.16 to 32.30 (mmolc L-1)1/2, while in the saturation extracts, the pH, EC and SARor ranged from 4.81 to 8.58, 0.08 to 72.4&nbsp;dS m-1 and 0.11 to 33.09 (mmolc L-1)1/2, respectively. The salinity problems in the study area are closely related to the intrusion of salts from the marine system.</p> 2023-05-28T18:58:28+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Quelites in poultry feed 2023-05-28T18:59:00+00:00 Marco Antonio Camacho-Escobar Martha Patrícia Jerez-Salas Serafín Jacobo López-Garrido Mónica Marcela Galicia-Jiménez Narciso Ysac Ávila-Serrano Edgar Iván Sánchez-Bernal <p>In traditional poultry farming, the consumption of fresh plants is an important part of the diet and a fundamental component of the indigenous poultry raising technique. Therefore, the objective is to know the studies that have included some quelites for feeding domestic birds. Quelite is a term used to refer to edible tender plants which are used as a whole plant, sprouts, branches, leaves, petioles, stems or flowers. The present review will consider the quelites Amaranth (Amarantus sp.), Chepil (Crotalaria longirostrada), Epazote (Dysphania ambrosioides), Blackberry (Solanum americanum), Holy grass (Piper autitum), Guaje (Leucaena leucocephala), Huazontle (Chenopodium berlandieri subsp. nuttalliae) and Purslane (Portuca olerecea). Nutritional and nutraceutical characteristics of these chelites are presented. In tests of egg and meat production, both in hens and in native turkeys, the main results of these studies are presented. The use of quelites in poultry farming has begun to be tested in order to reduce production costs, without af fecting the productive variables or the quality of eggs or meat. Although contradictory information has been reported, there is enough evidence to continue this line of study. It is proven that quelites have dif ferent nutritional and nutraceutical properties, which are intended to be used in favor of producers and consumers; however, much research is lacking.</p> 2023-05-28T18:51:10+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Heavy metals in water and macroinvertebrates of the Ayuquila-Armería river basin (Mexico) and its af fluents 2023-05-28T18:59:21+00:00 Oscar Raúl Mancilla-Villa Larissa Gómez-Villaseñor Carlos Palomera-García Omar Hernández-Vargas Rubén Darío Guevara-Gutiérrez Héctor Manuel Ortega-Escobar Héctor Flores-Magdaleno Álvaro Can-Chulim Edgar Iván Sánchez-Bernal Juan Uriel Avelar-Roblero Elia Cruz-Crespo <p>The Ayuquila-Armería river basin is classified as a priority hydrographic basin in Mexico for its high diversity and for the ecosystem pressure it is subjected to. The objective of this study was to determine the concentrations of heavy metals (As, Cd, Cr, Hg, Pb and Zn) in water and aquatic macroinvertebrates, in addition to physical and chemical parameters (pH, EC and flow) in the tributary basins and the main channel. The present investigation was carried out with samplings in the rainy season in 2015, and in the dry season in 2016, at 18 sites in the basin. Determinations of heavy metals, physical and chemical parameters, collection of aquatic macroinvertebrates and estimation of the flow of the tributaries were carried out at each sampling site. In surface water, only Hg and Pb exceeded the permissible limits for natural waters (0.02 and 0.0015 mg L-1 respectively) in 60% of the sites; in terms of concentrations in macroinvertebrates, the six metals exceeded the permissible limits in the 65% of the sites with concentrations of 0.33 to 7.07 mg kg-1, of these the Hg (7.07 mg&nbsp;kg‑1) and the metalloid As (5.19 mg kg-1) were the ones that presented the highest concentrations.</p> 2023-05-28T18:44:03+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Tolerance of hybrids of the genus Brachiaria to various greenhouse saline conditions in Santa Elena, Oaxaca 2023-05-28T18:59:39+00:00 Edgar Iván Sánchez-Bernal Héctor Manuel Ortega-Escobar Verónica Ortega-Baranda Álvaro Can-Chulim Serafín Jacobo López-Garrido Jorge Ochoa-Somuano <p>In a greenhouse on the coast of Oaxaca, the tolerance of the hybrids pasture of the genus Brachiaria: Cobra (BR02/1794), Cayman (BR02/1752), Camello (GP 3025) and Mulato II (CIAT 36087) to induced saline conditions by NaCl, MgCl2 and NaHCO3, was evaluated with seven salinity levels: 0, 1.13, 2.48, 3.84, 5.19, 6.40 and 9.60 g&nbsp;L-1. The percentage of emergence, plant height, stem diameter, number of leaves and tillers, root length and biomass production were recorded. The experimental design was made up of a factorial with three salts, seven salinity levels, four grasses and three repetitions, which yield a total of 252 experimental units. The emergence percentage incresead over time in all cases and the growth parameters plant: height, stem diameter, number of leaves, and tillers, root lenght and total biomass production, decreased as the saline level increased in the following order Cobra at a saline threshold of 5.19 g L-1of NaCl, which is why it is considered moderately sensitive. While the grass that produced the least amount of biomass (0.34 g pl-1) was Cayman at a saline concentration of 1.13 g L-1 of NaHCO3. The experimental salts produced dwarfism and growth inhibition at concentrations greater than 6.40 g L-1, a phenomenon intensified by NaHCO3. The low tolerance of Cobra, Cayman, Camello and Mulato II grasses to NaCl, MgCl2 and NaHCO3 salts at concentrations &gt; 3.84&nbsp;g&nbsp;L-1 limits its cultivation to the coastal plain of Oaxaca. However, its implementation in field is possible with the application of sustainable techniques for the use and management of soil and irrigation water, to reduce the ef fects of salinity and improve forage production.</p> 2023-05-28T18:35:26+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Variation of water quality in the main channel of the Panuco river basin 2023-06-01T19:22:18+00:00 Juan Uriel Avelar-Roblero Héctor Manuel Ortega-Escobar Oscar Raúl Mancilla-Villa Abdul Khalil Gardezi Isabel Mendoza-Saldivar Edgar Iván Sánchez-Bernal Álvaro Can-Chulim <p>The use of wastewater in agricultural irrigation contributes to improving soil productivity and solving water scarcity problems. However, problems of salinity and sodicity in the soil, toxicity to plants, and public health problems are generated. In the Pánuco River basin, which originates in the Valley of Mexico and flows into the Gulf of Mexico, is the Valle del Mezquital, where approximately 90,000 ha are irrigated with wastewater that arrives through various routes, including the Great Drainage Canal. A part of the water that is used for irrigation infiltrates and is incorporated into the bed of the Tula River, which flows into the Zimapán dam. From the Zimapán dam, the channel acquires the name of the Moctezuma River and in the lower part of the Pánuco River basin until it discharges into the Gulf of Mexico. The objective of this work was to evaluate the water quality along the channel of the Pánuco river basin through sampling, laboratory determinations and analysis through quality indices with agronomic criteria, and to compare the results of the upper part of the basin with the lower part. The results indicate that the wastewater that enters the Mezquital Valley has an impact along the entire channel, but to a greater extent in the upper part of the basin. In all the sample points, the water is classified as bicarbonate-sodium, the RSC index indicates that 96% of the sites present some type of irrigation restriction, the EC is not ideal in any of the points and the sodium adsorption ratio (SAR) evidences sodicity risks.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Hydrochemistry and water quality for irrigation of RH 21 and 23 costa de Oaxaca and costa de Chiapas, Mexico 2023-06-01T19:22:21+00:00 Adriana Camacho-Ballesteros Héctor Manuel Ortega-Escobar Edgar Iván Sánchez-Bernal Héctor Flores-Magdaleno Abdul Khalil Gardezi Isabel Mendoza-Saldivar Teobaldis Mercado-Fernández Juan Uriel Avelar-Roblero <p>The hydrological region 21 coast of Oaxaca has an active tourist dynamic, it generates significant economic income, and it is considered the fourth most important socioeconomic region in the state of Oaxaca. Similarly, hydrological region 23 coast of Chiapas, has an economy governed by tertiary sector activities and is comprised of the Istmo-Costa and Soconusco socioeconomic regions, the latter is the main region that contributes to the gross domestic product of the state of Chiapas. It should be noted that this socioeconomic growth has required a greater demand for water resources, which has led to water pollution. The deterioration of the area’s water resources is caused by the discharge of wastewater, solid waste and agrochemicals into natural waterways. In order to assess the state of the water resources of hydrological regions 21 and 23, 31 sampling sites were established in the spring of 2021 distributed in the main streams. Each sample was analyzed for chemical properties: pH, electrical conductivity (EC), major anions and cations (CO32-, HCO3-, Cl-, SO42-, Ca2+, Mg2+, Na+ and K+), total dissolved solids (TDS), percentage of sodium (%Na), adsorption ratio of sodium (RAS), residual sodium carbonate (RSC), permeability index (PI), as well as a hydrochemical evaluation. The waters of the hydrological regions 21 and 23 present as dominant facies the calcium-magnesium bicarbonate, whose possible origin is a consequence of the dilution process of the geological material (water-rock interaction) with low and medium concentrations. With respect to salinity, 45.16% are low salinity waters and 93.55% of the sites have low sodium, therefore, they are considered recommended for irrigation with moderate restrictions.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Population structure and phenology of cuachalalate (Amphipterygium adstringens) developed on degraded lithosol in the coast of Oaxaca 2023-05-01T22:11:59+00:00 Verónica Ortega-Baranda Deysi Lizeth de la Cruz-Salinas Angélica Romero-Manzanares Edgar Iván Sánchez-Bernal <p>Amphipterigyum adstringens “cuachalalate” is growing on degraded soils of the low deciduous forest of the coast of Oaxaca. Two objectives were carried out: 1. On cuachalalate: to define the vertical and horizontal population structure, to identify the dispersal pattern of the individuals, and observe the period of the phenological phases. 2. On the soil: to determinate the physical and chemical characteristics of the degraded Lithosol of San Pedro Mixtepec, Oaxaca, where cuachalalate is growing. In sites of 1000 m2 all cuachalalate individuals were registered. These were classified by growing stage (saplings, juveniles and trees). To analyze the size hierarchy, the horizontal and vertical structure of the cuachalalate populations was analyzed. The spatial dispersion of populations was estimated with the Morisita Index. Phenological events were recorded in the trees: foliation, female and male flowering, fruiting and defoliation, during one year (2017 rainy season to 2018 dry season). The cuachalalate presented lower (2.0 to 9.5 m) and upper (10.0 to 16.0 m) vertical structure; the horizontal structure showed that saplings and juveniles have diameters &lt; 2.5 cm, and trees of 5 to 10 cm. The spatial distribution of the populations is aggregated. Flowering occurred during the rainy season, fruiting during rainy to dry season of next year, foliation from dry to rainy season of the same year and defoliation from rainy season to dry season of next year. Degraded lithosols tend to be eroded by runof f, are impermeable and hydrophobic. The piedmont soils have physical and chemical characteristics that highlight incipient accumulation processes, which anticipate a transition to an eutrophic regosol, a favorable soil for the persistence of the low deciduous forest.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA The challenge to establish tree species in saline soils of the former Texcoco lake 2023-05-01T22:11:14+00:00 César Ortiz-Torres Armando Gómez-Guerrero Héctor Manuel Ortega-Escobar Javier López-Upton Francisca Ofelia Plascencia-Escalante Tomás Martínez-Trinidad <p>Due to high pressure for the urbanization of areas of the saline-sodic soils (SSS) around the former Texcoco lake, Sate of Mexico, it is important to find strategies for tree planting. The aim of the study was to determine the response of five tree species; Pinus greggii, P. pseudostrobus, P. ayacahuite, P. leiophylla and as reference species Psidium guajava, established in holes filled with an alternative substrate (HAS) in SSS. Fif ty holes 1 m depth and 0.60 m in diameter were excavated and filled with an alternative substrate. The pH, electrical conductivity (EC), mechanical resistance (MR), volumetric water content, relative water content (RWC) in plant tissue and survival at 280 days were measured. The HAS presented lower values with respect to the control (SSS): in pH, 8.99 vs. 9.95; in EC, 2.58 vs. 8.19 dS m-1; in volumetric water content, 0.41 vs. 1.06 cm3 cm-3; and in mechanical resistance, 1.72 vs. 2.53 MPa. The RWC increased at 120 days in P. ayacahuite (from 74.7 to 81.5%) and P. leiophylla (75.2 to 77.5%), while in P. guajava it decreased (92.8 to 75.5%). Survival af ter 280 days for P. guajava (70%) exceeded that of pines (1.67%). P. guajava was the species the better performed, whereas pines did not survived salinity. HAS was helpful in the establishment of tree species by providing healthier environment despite the adverse conditions of the SSS.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Dry matter production and description of morphological components of two cultivars of the Urochloa hybrid 2023-05-01T22:10:24+00:00 Eliud Flores-Morales Serafín Jacobo López-Garrido Mónica Marcela Galicia-Jiménez Narciso Ysac Ávila-Serrano Marco Antonio Camacho-Escobar Jaime Arroyo-Ledezma <p>The evaluation of the growth of the improved Cobra and Cayman grasses during the first ten weeks of establishment in the rainy season in the tropics are important to estimate the development of the morphological components, because through these elements it is possible to evaluate their potential biomass production available for feed the cattle. The objective of the present study was to characterize the morphological components and their contribution to biomass production at dif ferent weeks of growth of the cultivars Cayman (CIAT BR02/1752) and Cobra (CIAT&nbsp;BR02/1794), hybrids of the genus Urochloa during the rainy season. The cultivars were established during the rainy season and the percentage of emergence, leaf length (LL), leaf width (LW), plant height (PH), stem diameter (SD) and number of shoots (NS) were evaluated. The morphological components were determined by the destructive method, and leaf dry weight (LDW), stem dry weight (SDW) and root dry weight (RDW) were also evaluated. The data were analysed with the SAS statistical program through PROG GLM, the comparison of means was performed by Tukey’s test. The results showed the variables LL, PH, NS and LW were not dif ferent (P &gt; 0.05) among cultivars at dif ferent weeks. On the other hand, for SD there was no dif ference between cultivars. The Cobra and Cayman cultivars had similar responses in the production of morphological components and dry matter production during the growth periods evaluated during the rainy season.</p> 2023-04-30T00:00:00+00:00 Copyright (c) 2023 REVISTA TERRA LATINOAMERICANA Editorial Committee 2023 2023-02-14T22:29:52+00:00 Alejandro Rodríguez-Barba 2023-01-31T00:00:00+00:00 Copyright (c) Portada Interna 2023 2023-01-24T20:52:01+00:00 Alejandro Rodríguez-Barba 2023-01-31T00:00:00+00:00 Copyright (c)