Interacción de las propiedades físicas de un suelo agrícola: resistencia a la penetración y humedad volumétrica

The spatial variability of the physical property resistance to penetration in a soil with agricultural vocation under a rice cultivation system was studied. For the design of spatial variability maps in a study area of 22.6 ha located in the town of San José de la Vega, Municipality of San José de Cúcuta, the different variables were classified and analyzed, achieving the representation of the information obtained in the field using the "QGIS" software for the classification and distribution of the study area. A quantitative experimental method was carried out for the study, which was divided into a systematic grid with 27 points located by means of coordinates. At each point, measurements corresponding to the physical properties were made, which were: resistance to penetration, where four measurements were taken for each depth level (0-5cm, 5-10cm, 10-15cm and 15-20cm) and averaging each measurement. In the 10 to 20 cm resistance, significant values were recorded in the ranges of 3.8 and 8.42MPa from the sampling points. The moisture retention measurement is made up of the ranges of 31.1% minimum and 50.2% maximum.Se estudió la variabilidad espacial de la propiedad física resistencia a la penetración en un suelo con vocación agrícola bajo un sistema de cultivo de arroz. Para el diseño de los mapas de variabilidad espacial en un área de estudio de 22,6 ha ubicada en el corregimiento de San José de la Vega, Municipio de San José de Cúcuta, se clasificaron y analizaron las diferentes variables, logrando la representación de la información obtenida en campo utilizando el software "QGIS" para la clasificación y distribución del área de estudio. Para el estudio se realizó un método experimental cuantitativo, el cual se dividió en una malla sistemática con 27 puntos localizados mediante coordenadas. En cada punto se realizaron las mediciones correspondientes a las propiedades físicas, las cuales fueron: resistencia a la penetración, donde se realizaron cuatro mediciones para cada nivel de profundidad (0-5cm, 5-10cm, 10-15cm y 15-20cm) y promediando cada medición. En la resistencia de 10 a 20 cm se registraron valores significativos en los rangos de 3,8 y 8,42MPa de los puntos de muestreo. La medición de la retención de humedad está compuesta por los rangos de 31,1% mínimo y 50,2% máximo

Effect of colchicine on Kalanchoe daigremontiana Raym.-Hamet & H.Perrier (Crassulaceae) leaf morphology and stomates

1 recurso en línea (páginas 212-222).El presente estudio evaluó el efecto de diferentes concentraciones y tiempo de exposición de colchicina, sobre la morfología foliar y los estomas de Kalanchoe daigremontiana. Inicialmente, se recolectaron y se sometieron las plántulas de K. daigremontiana a concentraciones de 0,025% y 0,1% (p/v) de colchicina y a dos tiempos de exposición (24 y 48 horas). Posteriormente, se realizaron estudios morfológicos como la altura de la planta (AP), anchura de la hoja (AH), número de hojas (NH), longitud foliar (LH), espesor de hoja (EH) y volumen foliar (VH) cada 15 días, durante 16 semanas después de la siembra. Luego, se caracterizaron los estomas, teniendo en cuenta el ancho, el largo, índice estomático y el número de cloroplasto por estoma. Se encontró un incremento significativo en la morfología foliar y estomática, en los tratamientos con colchicina de 0,025% a 24 y 48 horas. Lo que demuestra que el uso de la colchicina logra un mayor crecimiento en poco tiempo y aumento de la biomasa en la planta medicinal K. daigremontiana.The current study evaluated the effect of different concentrations and exposure times of colchicine on Kalanchoe daigremontiana leaf morphology and stomates. Initially, K. daigremontiana seedlings were harvested at concentrations of 0.025% and 0.1% (w/v) of colchicine and at two exposure times (24 and 48 hours). Subsequently, morphological studies, such as plant height (PH), leaf width (LW), number of leaves (NL), leaf length (LL), leaf thickness (LT) and leaf volume (LV), were done every 15 days for 16 weeks after sowing. Afterwards, the stomates were characterized, taking into account the width, length, stomatal index and number of chloroplasts per stomate. A significant increase in foliar and stomatal morphology was found in treatments with colchicine of 0.025% at 24 and 48 hours. This shows that the use of colchicine achieves greater growth in a short time and increased biomass in medicinal K. daigremontiana plants.Bibliografía: páginas 221-22

Optimización de la prueba de tetrazolio para evaluar la viabilidad en semillas de Solanum lycopersicum L.

Tomato (Solanum lycopersicum) is one of the most consumed vegetables worldwide with increasing demand. Therefore, knowing its seeds viability is of utmost importance since these are the basis of their production success. Accordingly, the study aimed at optimizing the tetrazolium test by determining the appropriate pretreatment to enhance it. Plant material was collected from crops established in the municipality of Cáchira, department of Norte de Santander, Colombia. The seeds were extracted from ripe fruits and subsequently exposed to preconditioning with sodium hypochlorite and distilled water for 10 minutes, with three concentrations of 2,3,5-triphenyl tetrazolium chloride (0.25 %, 0.15 %, and 0.10 %) and different exposure times (6 h, 12 h, and 24 h). The viability data obtained were corroborated by the germination test on wet paper towels. The viability results with the highest correlation with the germination test were obtained using the 0.25 % and 0.15 % concentrations, and utilizing the pre-conditioning treatment with sodium hypochlorite as well as immersion in distilled water.El tomate (Solanum lycopersicum) es una de las hortalizas más consumidas en el mundo con un aumento en su demanda, por lo que conocer la viabilidad de sus semillas es de suma importancia, ya que estas son la base del éxito de su producción. Debido a esto, el presente estudio tuvo como objetivo optimizar la prueba de tetrazolio determinando el pretratamiento adecuado para potenciar la prueba. El material vegetal se recolectó de cultivos establecidos en el municipio del Cáchira, departamento de Norte de Santander, Colombia. Las semillas se extrajeron de los frutos maduros y, posteriormente, se expusieron a pretratramientos con hipoclorito de sodio y agua destilada durante 10 minutos, con tres concentraciones de 2, 3, 5- cloruro trifenil tetrazolio (0,25 %, 0,15 % y 0,10 %) y distintos tiempos de exposición (6 h, 12 h y 24 h). Los datos de viabilidad obtenidos se corroboraron mediante la prueba de germinación en toallas de papel húmedas. Los resultados de viabilidad más relacionados con la prueba de germinación se obtuvieron al emplear las concentraciones de 0,25 % y 0,15 %, utilizando tanto el pretratamiento con hipoclorito de sodio como la inmersión en agua destilada. &nbsp

Determinación de la viabilidad de semillas de capsicum annuum L usando la prueba de tetrazolio

Paprika (Capsicum annuum L) is one of the most important and widely cultivated vegetable crops worldwide. This studydetermined the efficacy of the tetrazolium test to obtain the viability of C. annuum seeds. So, C. annuum seeds were exposed to twoconcentrations (1% and 0.5%) of tetrazolium and two exposure times (24 and 48 hours). The tetrazolium test is based on the coloration of theembryo and living tissues of the seed, thanks to the oxidation of the tetrazolium salt by cellular respiration. Subsequently, using a stereoscopemicroscope, the staining of the seeds was assessed, estimating as viable seeds those that presented red coloration in the embryo. Therefore,statistically significant differences (P≤ 0.05) were obtained in the T4 treatment (0.5%, 48h) with 99% viability. Likewise, the treatments T1(1%, 24h) and T2 (0.5%, 24h) did not show differences between them, the viability percentage being 89% and 91% respectively. For the realgermination test, 84.4% (average) of germination was obtained for the 5 repetitions. It is concluded that through the tetrazolium test theassessment of the viability in paprika seeds is efficient for concentrations of 1% and 0.5%, for 24 hours.El pimentón (Capsicum annuum L) es uno de los cultivos de hortalizas más importantes y ampliamente cultivados a nivelmundial. Este estudio determinó la eficacia del test tetrazolio para obtener la viabilidad de semillas de C. annuum. De manera que, semillas deC. annuum se expusieron a dos concentraciones (1% y 0.5%) de tetrazolio y dos tiempos de exposición (24 y 48horas). La prueba de tetrazoliose fundamenta en la coloración del embrión y tejidos vivos de la semilla, gracias a la oxidación de la sal de tetrazolio por la respiración celular.Ulteriormente, utilizando un microscopio estereoscopio se valoró la tinción de las semillas, estimando como semillas viables las que presentaroncoloración roja en el embrión. Por consiguiente, se obtuvieron diferencias estadísticamente significativas (P≤ 0,05) en el tratamiento T4 (0.5 %,48h) con un 99% de viabilidad. Así mismo, los tratamientos T1 (1 %, 24h) y T2 (0.5 %, 24h) no presentaron diferencias entre sí, siendo elporcentaje de viabilidad 89% y 91% respectivamente. Para la prueba de germinación real, se obtuvo un 84.4% (promedio) de germinación paralas 5 repeticiones. Se concluye que mediante el ensayo de tetrazolio la valoración de la viabilidad en semillas de pimentón es eficiente para lasconcentraciones de 1% y 0.5 %, durante 24 hora

Cytotoxic evaluation of glyphosate, using Allium cepa L. as bioindicator

Glyphosate is a chemical compound used mainly as a broad spectrum herbicide, it is recognized for its proven effectiveness and easy handling. It represents more than 60% of the world market of non-selective herbicides and is used in both agricultural fields and family gardens. The present study was designed to test the cytogenotoxic potential of glyphosate using the Allium cepa test as toxicity bioindicator. Consequently, bulbs of A. cepa were exposed to different concentrations of glyphosate (5, 10, 15, 25 and 30 mgL−1) and a control (deionized water), for 72 h; root development was also studied in this period of time. The cytogenotoxic potential of glyphosate was determined by calculating the mitotic index (MI), cellular anomalies (CA) and registering the roots longitudinal growth at 24, 48 and 72 h. Regarding root development, a greater growth was observed in the control treatment in the three measurement times. The mitotic phases analysis, determined that the higher the concentration, the lower the mitotic index, in addition the inhibition of the telophase Mitotic Index (TMI) was observed in any of the concentrations. The results indicate that the exposure to glyphosate of A. cepa meristematic cells induces diverse types of chromosomal anomalies, such as micronuclei (MN), chromosome breaking (CB), nuclear notch (Nn), among others. Therefore, in demonstrates that glyphosate has a highly cytogenotoxic effect for any of the concentrations used

Determination of malathion's toxic effect on Lens culinaris Medik cell cycle

The present study aimed to determine the toxic effect of malathion pesticide on root growth, cell division and the chromosomal abnormalities frequency using the L. culinaris test. Initially, the lentil seeds were subjected to different doses of malathion (0.0 0.5, 1, 2.5, 5, 10, 15, 20, 25 and 30 mgL-1) and during 24, 48, and 72 h, the root length was measured. Subsequently, at 72h, the mitotic index, mitotic inhibition, and cellular abnormalities were calculated for all treatments. According to the obtained results, it was visualized that the root growth was inversely proportional to the concentration of malathion at all times of exposure. After 72h of exposure, the lowest values of the mitotic index and inhibition were presented at malathion concentrations 20, 25 and 30 mgL-1. Additionally, micronuclei cell abnormalities, metaphase sticky chromosomes, split chromosomes, nuclear lesions, irregular anaphase, anaphase bridges, binucleated cells, absence of nucleus and telophase bridge were observed. Finally, Malathion induced mitodepressive and cytotoxic effects in the meristematic cells of the L. culinaris root tip. A high frequency of abnormality was found in the micronuclei, which represented an indicator of a high degree of toxicity at the cellular level

Use of Lens culinaris Med test as environmental bioindicator to identify the cytogenotoxic effect of paraquat pesticide

Paraquat is the most widely used herbicide and the third most sold pesticide in the world, applied in more than 120 countries despite being banned in the European Union. It is a risk to ecosystems. The genotoxic effect of paraquat was evaluated using the Lens culinaris test. L. culinaris seeds were subjected to 6 concentrations of paraquat (0.1, 0.5, 1, 1.5, 1.5, 2, and 3 ppm) plus a control (distilled water). During 72 h, root development was measured every 24 h. After 3 days, root apices were analyzed to obtain the inhibition of the mitotic index, as well as the type and rate of chromosomal abnormalities present. A decrease in root growth of more than 50% (72 h of exposure) and an inhibition of the mitotic index of 2.9 times in the treatment with 3 ppm compared to the control were observed. The 2 ppm concentration presented all the anomalies found with a frequency of 84 ± 2.5 of micronuclei, 106 ± 3.5 of nuclear lesions, 14 ± 4.7 of nucleus absence, 8 ± 2.7 of telophase bridges, 7 ± 2.7 of binucleated cells, among others. It is also recommended to establish comparisons of L. culinaris with multiple biomarkers since it is presented as a practical and economic alternative

Evaluación de la calidad fisiológica de las semillas de Linum usitatissimum L. con la prueba de tetrazolio

La linaza es una planta herbácea de la familia de las lináceas que corresponde a la semilla del lino (Linum usitatissimum L.) utilizada tradicionalmente como oleaginosa. El interés por estas semillas aumenta por el reconocimiento de algunos de sus componentes con potenciales beneficios para la salud. En este estudio se determinó la eficacia de la prueba de viabilidad de tetrazolio en semillas de L. usitatissmum. En consecuencia, se sometieron semillas de L. usitatissmum a cuatro tratamientos, los cuales consistieron en dos concentraciones (0.5 % y 1 %) y dos tiempos de exposición (24h y 48h). Posteriormente, se evaluó la tinción de las semillas con la ayuda de un microscopio estereoscopio, tomando como semillas viables las que presentaron coloración roja en el embrión, de esta forma se pudo obtener diferencias estadísticamente significativas (P ≤ 0,05: Tukey HSD) para el tratamiento T1 (0.5 %, 24h) con un 65% de semillas viables. Del mismo modo, no se observaron diferencias entre los tratamientos T2 (1 %, 24h), T3 (0.5 %, 48h) con viabilidad del 86% y T4 (1 %, 48h) con 89 % de viabilidad. En cuanto a la prueba de germinación, en promedio se obtuvo un 86 % en las cinco repeticiones con una desviación estándar de 9.63. Se concluye que la evaluación de la viabilidad en semillas de linaza mediante ensayo de tetrazolio es eficiente para las concentraciones de 1 % durante 24 y 48 horas y para 0.5 % a 48 horas de exposición

Efecto de pretatamientos en la prueba de tetrazolio en semillas de Epidendrum barbaricum Hágsater & Dodson

Orchids are affected by several factors that impair their spreading, which is necessary to know the viability of their seeds. The aim of this research was to determine the most suitable preconditioning treatment to potentiate the tetrazolium test in Epidendrum barbaricum seeds. Initially, the mature capsules were collected near the city of Pasto in the Department of Nariño (Colombia), and seeds were obtained. Subsequently, the seeds were submitted to four pretreatments: immersion in distilled water, 1% hypochlorite, 10% alcohol and 10% sucrose. Seeds were then rinsed with distilled water and exposed to two concentrations of 2,3,5-trifenyl tetrazolium chloride (0.25%, 1%) and different exposure times (6, 12, 24, and 48 hours). To perform the tests, the 5 ml syringe with cloth filter method was used. The viability test results were corroborated with the in vitro germination test, using the MS (Murashige and Skoog) culture medium. The most reliable viability findings (93%) were obtained by using preconditioning with sodium hypochlorite, a value that has a high correlation with the percentage of germination (93%), independent of the tetrazolium concentration at an exposure time of 24 hours.Las orquídeas son afectadas por varios factores que perjudican su propagación. En este estudio se evaluaron diferentes métodos de pre-acondicionamento para potenciar la prueba de tetrazolio en semillas de Epidendrum barbaricum. Inicialmente las cápsulas maduras fueron recolectadas en la ciudad de Pasto, departamento de Nariño (Colombia), las cuales fueron sometidas a los pretratamientos: inmersión en agua destilada, hipoclorito al 1%, alcohol al 10% y sacarosa al 10%, antes de ser lavadas con agua destilada y tratadas con concentraciones de 2,3,5- cloruro trifenil tetrazolio (0.25%, y 1%) durante tiempos de exposición de 6, 12, 24 y 48 horas. Para las aplicaciones fueron utilizadas jeringas de 5 ml con filtro de tela. Los resultados del test de viabilidad fueron validados con la prueba de germinación in vitro, utilizando el medio de cultivo MS (Murashige and Skoog). Los mejores porcentajes de viabilidad (93%) se encontraron con la aplicación de hipoclorito de sodio, con una alta correlación con el porcentaje de germinación (93%), independiente de la concentración de tetrazolio y un tiempo de exposición de 24 horas

Implementação do teste de tetrazólio nas sementes de Raphanus sativus L

Radish (Raphanus Sativus) is a significant species due to its nutritional properties, the high oil percentage of its seeds and the large number of usable metabolites. The production of this crop is influenced by factors such as the use of high or low-quality seeds. Therefore, this study evaluated the implementation of a tetrazolium test as a method to determine viability in Raphanus Sativus seeds. Initially, seeds produced in Villa del Rosario, Norte de Santander, Colombia were collected and exposed to two concentrations (0.5 % and 1,0 %) under two exposure times (24 and 48 hours). They were subsequently observed in the stereoscope to determine a viability percentage by counting the seeds that showed intense red coloring in their embryo stage; 99 % and 97 % viable seeds were obtained with treatments T2 (0.5 %, 24 h) and T4 (0.5 %, 48 h), accordingly; there were no statistically significant differences between them (p ≤ 0.05: Tukey’s HSD). Compared with the germination test that obtained 99 % on average, treatments T2, T3 and T4 showed no statistically significant differences. It was found that the viability test with tetrazolium is effective at 0.5 % and 1.0 % concentrations, during 24 and 48-hour exposure times.El Rábano (Raphanus sativus) es una especie de gran importancia por sus propiedades nutricionales, el alto porcentaje de aceite en sus semillas y la gran cantidad de metabolitos aprovechables. La producción de este cultivo se ve influenciada por factores como la utilización de semillas de alta o baja calidad. Es por esto que, en este estudio, se evaluó la aplicación del test de tetrazolio como método para determinar la viabilidad en semillas de Raphanus sativus. Inicialmente, se recolectaron semillas producidas en Villa del Rosario, Norte de Santander, Colombia, las cuales fueron expuestas a dos concentraciones (0,5 % y 1,0 %) y dos tiempos de exposición (24 y 48 horas). Posteriormente, fueron observadas en el estereoscopio para determinar el porcentaje de viabilidad, contabilizando las semillas que presentaron intensa coloración roja en su embrión; se obtuvieron un 99 % y 97 % de semillas viables con los tratamientos T2 (0,5 %, 24 h) y T4 (0,5 %, 48 h) respectivamente, no existiendo diferencias estadísticamente significativas entre sí (p ≤ 0,05: Tukey HSD). En comparación con la prueba de germinación, en la que se obtuvo un promedio de 99 %, no presentaron diferencias estadísticamente significativas los tratamientos T2, T3 y T4. Se concluyó con esto que la prueba de viabilidad con tetrazolio es efectiva a concentraciones de 0,5 % y 1,0 %, durante tiempos de exposición de 24 y 48 horas.O rabanete (Raphanus sativus) é uma espécie de grande importância por suas propriedades nutricionais, pela alta porcentagem de óleo em suas sementes e pela grande quantidade de metabólitos aproveitáveis. A produção desse cultivo vê-se influenciada por fatores como a utilização de sementes de alta ou de baixa qualidade. É por isso que, neste estudo, avaliou-se a aplicação do teste de tetrazólio como método para determinar a viabilidade em sementes de Raphanus sativus.Inicialmente, coletaram-se sementes produzidas em Villa del Rosario, Norte de Santander, Colômbia, as quais foram expostas a duas concentrações (0,5 % e 1,0 %) e dois tempos de exposição (24 e 48 horas). Posteriormente, foram observadas no estereoscópio para determinar a porcentagem de viabilidade, contabilizando as sementes que apresentaram intensa coloração vermelha em seu embrião; obtiveram-se 99 % e 97 % de sementes viáveis com os tratamentos T2 (0,5 %, 24 h) e T4 (0,5 %, 48 h) respectivamente, não existindo diferenças estatisticamente significativas entre si (p ≤ 0,05: Tukey hsd). Em comparação com o teste de germinação, no qual se obteve uma média de 99 %, os tratamentos T2, T3 e T4 não apresentaram diferenças estatisticamente significativas. Concluiu-se com isso que o teste de viabilidade com tetrazólio é efetivo a concentrações de 0,5 % e 1,0 %, durante tempos de exposição de 24 e 48 horas