Author: ANTONIO JUAREZ MALDONADO

Modelos matemáticos para el manejo del riego y nutrición del cultivo de tomate (Lycopersicon esculentum Mill.) en invernadero.

ANTONIO JUAREZ MALDONADO (2013)

El tomate es la hortaliza más importante a nivel mundial, en México este cultivo es de gran importancia ya que el 70% de la superficie cultivada que se produce bajo condiciones protegidas corresponde al tomate. Es importante realizar un manejo eficiente en la agricultura intensiva para lo que se requieren conocer los factores que condicionan el potencial de producción de los cultivos. El uso del agua por los cultivos es el factor de mayor importancia para determinar el rendimiento, la nutrición mineral es el segundo factor más importante. Es conveniente utilizar técnicas como la modelación matemática, que permitan diseñar estrategias para un manejo eficiente del agua y nutrientes en el cultivo de tomate. Se desarrollaron dos ciclos de cultivo de tomate durante los años 2011 y 2012 con el fin de generar la información necesaria para calibrar y validar un modelo dinámico de crecimiento. Se eliminaron cuatro plantas por semana en las que se determinó el peso fresco y seco de los diferentes órganos. Con el fin de conocer la relación que existe entre los diferentes órganos de la planta de tomate se realizaron análisis de correlación y de regresión entre éstos. Con los datos obtenidos se generaron curvas de crecimiento de las diferentes estructuras de la planta. También se midieron los consumos diarios de agua por las plantas para determinar la evapotranspiración y transpiración. Usando regresión múltiple se ajustaron ecuaciones para estimar la evapotranspiración y la transpiración diaria. Mediante instrumentación se midieron las variables climáticas. Así mismo, durante el desarrollo del cultivo se realizaron análisis minerales para determinar el contenido de N, P, K, Ca, Mg y S en los diferentes órganos de la planta. Con esta información se generaron ecuaciones de regresión para imitar el contenido de los minerales en las plantas, además de que los modelos de regresión se incluyeron en el modelo dinámico con el fin de simular dinámicamente los cambios en la concentración de los minerales a través del tiempo. Se encontró que el cultivo de tomate presentó una etapa de crecimiento exponencial a partir del trasplante y hasta la floración; y otra etapa de crecimiento lineal a partir de floración. Se demostró que existe una fuerte correlación entre los pesos frescos y secos de los diferentes órganos de la planta (P≤0.01), y en las diferentes etapas de crecimiento (P≤0.01). En cuanto al consumo de agua por las plantas de tomate, se generaron ecuaciones de regresión las cuales presentaron valores del índice R2 ajustado mayores a 0.90 tanto para estimar la transpiración como para estimar la evapotranspiración. Respecto a la modelación del crecimiento de tomate, los resultados mostraron que el modelo de crecimiento simula adecuadamente las salidas peso de hojas y peso de frutos (EF>0.95 e Index>0.95), para las salidas hojas cosechadas y frutos cosechados la simulación fue menos precisa (EF<0.90 e Index<0.90). Por su parte, la simulación de la concentración de los minerales fue adecuada para N, P, K, y S ya que tanto el EF como el index presentaron valores superiores a 0.95. En el caso del Ca y Mg las simulaciones de la concentración de estos presentaron valores del EF de 0.75 y 0.89 respectivamente. La información presentada en este trabajo es útil para el manejo del riego y la nutrición como factores más importantes del cultivo de tomate en invernadero. Con los modelos de regresión múltiple obtenidos es posible estimar las necesidades hídricas de las plantas de tomate bajo condiciones de invernadero a partir de variables sencillas de obtener. La modelación dinámica del crecimiento de tomate y del comportamiento de los minerales de mayor concentración es útil para la planificación del manejo del cultivo así como para diseñar estrategias más adecuadas para la nutrición del mismo.

The tomato is the most important vegetable worldwide. In Mexico, 70% of the cultivated area under protected conditions corresponds to tomato crop. It is important to have an effective management in intensive agriculture. In order to do so, it is important to understand the factors that determine the production potential of crops. Water use is the most important factor in determining the performance, the second one is mineral nutrition. It is convenient to use techniques such as mathematical modeling, in order to design strategies that allow for efficient management of water and nutrients in the tomato crop. Two crop cycles of tomato were developed during the years 2011 and 2012 in order to generate the information needed to calibrate and validate a dynamic growth model. Four plants per week were removed to determine fresh and dry weights of different tomato organs. In order to know the relationship between the different organs of tomato plant correlation analysis and regression were performed between them. The obtained data was used to generate different growth curves for plant structures. The daily water consumption was also measured to determine evapotranspiration and transpiration. Multiple regression equations were fitted to estimate daily evapotranspiration and transpiration. Through instrumentation, several climatic variables were measured. Mineral analyzes where performed during crop development to determine the contents of N, P, K, Ca, Mg and S in the various organs of the plant. With this information, regression equations were generated to mimic the mineral content in plants. Regression models were included in the dynamic model in order to dynamically simulate changes in mineral concentration over time. It was found that the tomato crop provided an exponential growth phase from transplanting until flowering, and a linear growth phase after flowering. It was shown that a strong correlation exists between the fresh and dry weights of different plant organs (P ≤ 0.01), and at different stages of growth (P ≤ 0.01). Regarding water consumption by tomato plants, regression equations were generated and they presented adjusted R2 index values greater than 0.90 for both estimated transpiration to estimated evapotranspiration. Regarding the modeling of tomato growth, the results showed that the model adequately simulates weight of leaves and fruit weight (EF> 0.95 and Index> 0.95). On the other hand, output for harvested leaves and harvested fruits, the simulation was less accurate (EF <0.90 and Index <0.90). Meanwhile, the simulation of the concentration of minerals was adequate for S, N, P, K, since both the EF index and the index showed values higher than 0.95. Simulation of Ca and Mg concentration showed EF values of 0.75 and 0.89 respectively. Information presented in this work is useful for irrigation management and nutrition, both considered as major factors in greenhouse tomato crop. Using the obtained multiple regression models is possible to estimate water needs of tomato plants under greenhouse conditions from simple variables. The dynamic modeling of tomato growth and mineral concentration is used for crop management planning and to design more suitable nutrition strategies.

Doctoral thesis

Tomate Cultivo Invernadero Modelos matemáticos Riego Nutrición CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Validación del modelo matemático de crecimiento nicolet b3 para el cultivo de lechuga (lactuca sativa l.) bajo condiciones de invernadero

ANTONIO JUAREZ MALDONADO (2010)

"El desarrollo de este trabajo se originó a partir del interés en el modelaje y simulación de hortalizas bajo condiciones de invernadero por ser una línea de investigación relativamente reciente en nuestro país, por lo que es de gran importancia el desarrollo de investigaciones sobre este tema ya que pueden ser de gran utilidad en el desarrollo y producción de hortalizas, ayudando en áreas como la optimización, planeación de cultivos, control de condiciones climáticas dentro del invernadero, selección de fechas de siembra y cosecha, planeación en la nutrición del cultivo, etc. v Se decidió trabajar con el cultivo de lechuga por ser un cultivo relativamente fácil de modelar y trabajar, además de que como es un área de investigación totalmente nueva en la universidad, específicamente en la Maestría en Ciencias en Horticultura, se seleccionó para la investigación el modelo matemático de crecimiento NICOLET B3 el cual se ha trabajado ampliamente en Europa por lo que es de importancia conocer sus habilidades en nuestro país. Por lo tanto, el objetivo del presente trabajo fue validar el modelo NICOLET B3 de crecimiento para el cultivo de lechuga bajo condiciones de invernadero en la región sureste de Coahuila, México. Para el desarrollo del experimento se utilizó semilla de lechuga (Lactuca sativa L.) var. “Great lakes” y se desarrolló el cultivo bajo condiciones de invernadero. A lo largo del cultivo se tomaron datos climáticos dentro del invernadero (CO2, temperatura y PAR) que fueron usados como entradas para el modelo, así mismo se tomaron muestras de cinco plantas seleccionadas completamente al azar dos veces por semana y se registraron la hora y fecha de muestreo y peso fresco, el peso seco se obtuvo después de secar las muestras por 48 horas a una temperatura de 80°C, estos datos fueron usados para comparar con las salidas del modelo y posteriormente su validación. La programación y simulación realizadas del modelo se trabajaron en la herramienta Simulink de MATLAB R2009a, en el que se utilizaron bloques para la programación de las ecuaciones, también, se utilizó un algoritmo de integración ode45. Para obtener la validación del modelo se utilizó el coeficiente de correlación ajustado R2, y el manejo de los datos se trabajó en Microsoft Excel 2010 (beta). "

"The development of the present work was originated by the interest in modeling and simulation of crop growth under greenhouse conditions and for being a relatively new research area in our country. That is why the research development about this topic is of great importance due to the fact that it is of great usefulness in horticulture production, helping in areas as culture planning and optimization, climatic conditions control in green houses, crop and seedling date selection, nutrition planning, etc. Lettuce crop was selected mainly because it is a relatively simple culture for working and modeling, besides the fact that it is a totally new research area in this university, specifically in the Master in Science in Horticulture Program. The NICOLET B3 model was selected for this research because it has been widely used in Europe so that it is important to know its potential in our country. Therefore, the objective of the present work was to validate NICOLET B3 model for lettuce growth under greenhouse conditions in the southeast region of Coahuila State, Mexico. In order to develop the experiment, “Great Lakes” variety lettuce seed (Lactuca sativa L.) was used and it was developed under greenhouse conditions. All through the culture process several climatic data were taken inside the green house: CO2, temperature and PAR. Those data were used as input to the model. In the same way 5 samples of randomly selected plants were taken twice a week where sampling dates and hours were registered. Fresh matter was measured and dry matter weight was taken registered after drying the samples for 48 hours at a temperature of 80ºC. Those data were used to compare the model output and validate the model. The model programming and simulation were carried out using the MATLAB R2009a Simulink tool, where blocks were used for equation representation and ode45 integration algorithm was used. In order to validate the model the adjusted correlation coefficient R2 was used and data was analyzed using the Microsoft Excel 2010 (beta)"

Master thesis

Lechuga Modelos Nicolet Cultivo CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Cu nanoparticles in chitosan-pva hydrogels as promoters of growth, productivity and fruit quality in tomato

HIPÓLITO HERNÁNDEZ HERNÁNDEZ ADALBERTO BENAVIDES MENDOZA HORTENSIA ORTEGA ORTÍZ ALMA DELIA HERNÁNDEZ FUENTES ANTONIO JUAREZ MALDONADO (2017)

"The encapsulation of copper nanoparticles (Cu NPs) in chitosan hydrogels could improve the yield and quality of fruit of horticultural crops due to the physicochemical properties of the NPs. The objective of this research was to evaluate different concentrations of Cu NPs in Chitosan-polyvinyl alcohol (Cs-PVA) hydrogels and their effects on the growth, productivity and fruit quality in tomato. The treatments were applied to the substrate as follows: 0.02, 0.2, 2 and 10 mg of Cu NPs in Cs-PVA hydrogel, Cs-PVA hydrogel alone and a control. The Cu NPs had significant effects on growth, productivity and fruit quality. They increased the numbers of leaves and clusters, fresh biomass of roots, and dry biomass of stem-leaves and roots of the plants. They also increased the soluble solid content, titratable acidity, lycopene content and total antioxidant capacity in the fruits. The concentration with the best effect on the growth and yield of tomato plants was 10 mg Cu NPs, which increased the stem diameter, dry biomass of stem-leaves (13%) and roots (30%) and the yield (17%), whereas the concentration of 0.02 mg Cu NPs increased the lycopene content (37%) and the total antioxidant capacity of the fruit (10%). The Cu NPs in Cs-PVA hydrogels helped to increase the yield and nutraceutical properties of the tomato fruits."

Article

Antioxidants Chitosan Cu nps Solanum lycopersicum Yield CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Organic acids combined with fe-chelate improves ferric nutrition in tomato grown in calcisol soil

FABIÁN PÉREZ LABRADA ADALBERTO BENAVIDES MENDOZA ANTONIO JUAREZ MALDONADO SUSANA SOLÍS GAONA SUSANA GONZALEZ MORALES (2017)

Plants developed in calcisol soils have limitations in iron nutrition, so exogenous applications of organic acids plus iron chelate can be an alternative. With the objective of knowing the answer of adding organic acids in the fertilizer solution plus a ferric chelate on the characteristics of the ferric nutrition of tomato plants developed in the calcisol soil the present experiment was established. We conducted the experiment in two stages, in the first stage studied differents concentration of some organic acids: citric acid (CA), oxalic acid (OA), salicylic acid (SA) and humic complexes (HC) combined with a FeEDDHA iron chelate, we included treatment control FeEDTA and FeEDDHA and treatment without iron in the fertilizer solution. In the second stage we compared the best concentrations of organic acids in combination with FeEDTA iron chelate; we used to treatment control FeEDTA and FeEDDHA, and a control treatment without iron in the fertilizer solution. The best concentrations were CA 10-4M, OA 10-4M, SA 10-5M and HC 0.4 ml/l. In the second stage, the addition of CA+FeEDTA and HC+FeEDTA increased SPAD units, chlorophyll and vitamin C contents and fruit quality improved. An increase content of Fe, Zn and Mn in leaves was presented with treatment CA+FeEDTA and HC+FeEDTA. Addition of CA+FeEDTA improved the oxidation- 1 reduction potential, pH and electrical conductivity of plant leachates, followed by HC+FeEDTA. Applications of CA and HC in the nutrient solution in combination with EDTA-type chelate improved the characteristics of the ferric nutrition of tomato plants developed in calcisol soil.

Plants developed in calcisol soils have limitations in iron nutrition, so exogenous applications of organic acids plus iron chelate can be an alternative. With the objective of knowing the answer of adding organic acids in the fertilizer solution plus a ferric chelate on the characteristics of the ferric nutrition of tomato plants developed in the calcisol soil the present experiment was established. We conducted the experiment in two stages, in the first stage studied differents concentration of some organic acids: citric acid (CA), oxalic acid (OA), salicylic acid (SA) and humic complexes (HC) combined with a FeEDDHA iron chelate, we included treatment control FeEDTA and FeEDDHA and treatment without iron in the fertilizer solution. In the second stage we compared the best concentrations of organic acids in combination with FeEDTA iron chelate; we used to treatment control FeEDTA and FeEDDHA, and a control treatment without iron in the fertilizer solution. The best concentrations were CA 10-4M, OA 10-4M, SA 10-5M and HC 0.4 ml/l. In the second stage, the addition of CA+FeEDTA and HC+FeEDTA increased SPAD units, chlorophyll and vitamin C contents and fruit quality improved. An increase content of Fe, Zn and Mn in leaves was presented with treatment CA+FeEDTA and HC+FeEDTA. Addition of CA+FeEDTA improved the oxidation- 1 reduction potential, pH and electrical conductivity of plant leachates, followed by HC+FeEDTA. Applications of CA and HC in the nutrient solution in combination with EDTA-type chelate improved the characteristics of the ferric nutrition of tomato plants developed in calcisol soil.

Article

organic anions humic complexes FeEDDHA FeEDTA leachates CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Determination of micronutrient uptake in greenhouse cucumber crop using a modeling approach

LINO JEREMÍAS RAMÍREZ PÉREZ AMERICA BERENICE MORALES DIAZ KARIM DE ALBA ROMENUS SUSANA GONZALEZ MORALES ADALBERTO BENAVIDES MENDOZA ANTONIO JUAREZ MALDONADO (2017)

"Control of micronutrients application in cucumber cultivation has great importance as they participate in many functions of metabolism. In addition, micronutrients application efficiency is fundamental to avoid periods of overconsumption or deficit in the crop. In order to determine the micronutrient uptake using a dynamic model, two cycles of Vitaly and Luxell cucumber crops were developed. During the development of the crop, micronutrients content (Fe, B, Mn, Cu and Zn) in the different organs of the cucumber plant was quantified. The model dynamically simulated the accumulation of biomass and micronutrients, using the climatic variables recorded inside the greenhouse as inputs. It was found that a decrease in the photosynthetically active radiation and in the temperature significantly diminishes the accumulation of biomass by cucumber plants. On the other hand, the results demonstrate that the model efficiently simulates both the accumulation of biomass and micronutrients uptake in cucumber crop. The indices used for the evaluation of efficiency showed values higher than 0.95. This dynamic model can be useful to define adequate strategies for the management of cucumber cultivation in greenhouses as well as the application of micronutrients."

Article

Mathematical modeling Cucumis sativus l Micronutrients uptake Simulation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Impact of Carbon Nanomaterials on the Antioxidant System of Tomato Seedlings

YOLANDA GONZALEZ GARCIA ELSY RUBISELA LOPEZ VARGAS Gregorio Cadenas Pliego Adalberto Benavides Mendoza SUSANA GONZALEZ MORALES ARMANDO ROBLEDO OLIVO Ángel Gabriel Alpuche Solís ANTONIO JUAREZ MALDONADO (2019)

"Tomato is one of the most economically important vegetables worldwide and is constantly threatened by various biotic and abiotic stress factors reducing the quality and quantity in the production of this crop. As an alternative to mitigate stress in plants, carbon nanomaterials (CNMs) have been used in agricultural areas. Therefore, the objective of the present work was to evaluate the antioxidant responses of tomato seedlings to the application via foliar and drench of carbon nanotubes (CNTs) and graphene (GP). Different doses (10, 50, 100, 250, 500, and 1000 mg L−1) and a control were evaluated. The results showed that the fresh and dry root weight increased with the application of CNMs. Regarding the antioxidant responses of tomato seedlings, the application of CNMs increased the content of phenols, flavonoids, ascorbic acid, glutathione, photosynthetic pigments, activity of the enzyme’s ascorbate peroxidase, glutathione peroxidase, catalase, and phenylalanine ammonia lyase as well as the content of proteins. Therefore, the use of carbon-based nanomaterials could be a good alternative to induce tolerance to different stress in tomato crop."

Article

Carbon nanotubes Graphene Antioxidant compounds Enzymatic activity Oxidative stress BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOQUÍMICA BIOQUÍMICA

Impact of Silicon Nanoparticles on the Antioxidant Compounds of Tomato Fruits Stressed by Arsenic

MAGIN GONZALEZ MOSCOSO NADIA VALENTINA MARTINEZ VILLEGAS Gregorio Cadenas Pliego Adalberto Benavides Mendoza MARIA DEL CARMEN RIVERA CRUZ SUSANA GONZALEZ MORALES ANTONIO JUAREZ MALDONADO (2019)

"Tomato fruit is rich in antioxidant compounds such as lycopene and β-carotene. The beneficial effects of the bioactive compounds of tomato fruit have been documented as anticancer activities. The objective of this research was to determine whether arsenic (As) causes changes in the content of antioxidant compounds in tomato fruits and whether Silicon nanoparticles (SiO2 NPs) positively influence them. The effects on fruit quality and non-enzymatic antioxidant compounds were determined. The results showed that As decreased the oxide-reduction potential (ORP), while lycopene and β-carotene were increased by exposure to As at a low dose (0.2 mg L−1), and proteins and vitamin C decreased due to high doses of As in the interaction with SiO2 NPs. A dose of 250 mg L−1 of SiO2 NPs increased glutathione and hydrogen peroxide (H2O2), and phenols decreased with low doses of As and when they interacted with the NPs. As for the flavonoids, they increased with exposure to As and SiO2 NPs. The total antioxidant capacity, determined by the ABTS (2,2´-azino-bis[3-ethylbenzthiazolin-6-sulfonic acid]) test, showed an increase with the highest dose of As in the interaction with SiO2 NPs. The application of As at low doses induced a greater accumulation of bioactive compounds in tomato fruit; however, these compounds decreased in high doses as well as via interaction with SiO2 NPs, indicating that there was an oxidative burst."

Article

Bioactive compounds Oxidative stress Lycopene Hydrogen peroxide β-carotene INGENIERÍA Y TECNOLOGÍA INGENIERÍA Y TECNOLOGÍA