The Use of Iodine, Selenium, and Silicon in Plant Nutrition for the Increase of Antioxidants in Fruits and Vegetables

Iodine, silicon, and selenium are considered elements not essential for the metabolism of plants. However, these elements are vital for humans, and their presence as traces in food is beneficial. The use of I, Si, and Se in the fertilization programs of the plants allows, on the one hand, the mineral biofortification of the crops and, on the other hand, through mechanisms not yet fully understood, the production and accumulation of more antioxidants in the edible organs. This chapter provides an overview about the use of I, Si, and Se both for mineral biofortification and for the increase in the concentration of antioxidants in plants, with an emphasis on redox metabolism adjustments and antioxidant chemical species studied. The scope of the chapter is on horticultural species in the open field and under greenhouse or tunnels

Yield and quality of hybrid tomato grafted and cultivated under shade mesh and greenhouse

The objective was to determine the yield, fruit quality and root development of four grafted tomato hybrids grown under anti-aphid mesh cover and greenhouse. The grafted hybrids were grown under shade mesh and greenhouse from april to november 2014. Variables evaluated were: fruit weight per plant, number of clusters per plant, number of fruits per plant, polar and equatorial fruit diameter, vitamin C and lycopene contents, and root fresh and dry weight. Hybrids grafted and cultivated under anti-aphid mesh had higher quality than the production obtained under greenhouse. However, lycopene and vitamin C contents and accumulated root system dry matter are greater under greenhous

Efecto de los ácidos fenólicos en el sistema antioxidante de plantas de tomate (Solanum lycopersicum Mill.)

Introduction. Phenolic acids belong to the group of phenolic compounds, their synthesis and concentration in plants increases when they are under biotic or abiotic stress conditions. Objective. To evaluate the effect of phenolic acids on the enzymatic and non-enzymatic antioxidant defense system in tomato plants subjected to biotic stress. Materials and methods. The experiment was carried out from March to December 2016, in Saltillo, Mexico. A tomate crop Saladette type of the Rio Fuego variety (Solanum lycopersicum Mill.) was stablished. Tomato plants inoculated with Clavibacter michiganensis subsp. michiganensis (1X105 CFU ml-1) were foliar sprayed with phenolic acids at a dose of 1 kg ha-1 with the Defens Gr® product (IA: phenolic acids 10 000 ppm). Leaves were sampled at 15, 31, and 92 days after the transplantation (ddt) and fruits at 90 ddt. Six treatments were used: 1) absolute control (T0), 2) application of phenolic acids before the inoculation with Clavibacter (AFA), 3) application of phenolic acids after inoculation with Clavibacter (AFD), 4) application of phenolic acids before and after inoculation with Clavibacter (AFAD), 5) only application of phenolic acids (AF), and 6) only inoculation with Clavibacter (Cmm). Results. The application of phenolic acids intervened in the activity of enzymatic and non-enzymatic antioxidants. A higher antioxidant capacity was found in leaf than in fruit, which was determined by ABTS (2,2’-azino-bis (3-ethylbenzothiazolin-6-sulfonic acid)) and DPPH (1,1-diphenyl-2-picrilhydrazil). The inoculation of tomato plants increased the activity of catalase and phenylalanine ammonium lyase enzymes in leaf; in addition, there was reduction of superoxide dismutase enzyme activity and total phenol content. Conclusion. Phenolic acids intervened in the enzymatic defense mechanisms of the plant and reduced the stress levels caused by inoculation.Introducción. Los ácidos fenólicos pertenecen al grupo de los compuestos fenólicos, su síntesis y concentración en las plantas aumenta cuando estas se encuentran bajo condiciones de estrés biótico o abiótico. Objetivo. Evaluar el efecto de los ácidos fenólicos sobre el sistema de defensa antioxidante enzimático y no enzimático en plantas de tomate sometidas a estrés biótico. Materiales y métodos. El experimento se realizó de marzo a diciembre de 2016, en Saltillo, México. Se estableció un cultivo de tomate tipo Saladette de la variedad Río Fuego (Solanum lycopersicum Mill.). A plantas de tomate inoculadas con Clavibacter michiganensis subsp. michiganensis (1X105 UFC ml-1) se les realizaron aspersiones foliares de ácidos fenólicos a una dosis de 1 kg ha-1 con el producto Defens Gr® (IA: ácidos fenólicos 10 000 ppm). Se muestrearon hojas a los 15, 31 y 92 días después del trasplante (ddt) y frutos a los 90 ddt. Se trabajó con seis tratamientos: 1) testigo absoluto (T0), 2) aplicación de ácidos fenólicos antes de inocular Clavibacter (AFA), 3) aplicación de ácidos fenólicos después de inocular Clavibacter (AFD), 4) aplicación de ácidos fenólicos antes y después de inocular Clavibacter (AFAD), 5) solo aplicación de ácidos fenólicos (AF) y 6) solo inoculación con Clavibacter (Cmm). Resultados. La aplicación de ácidos fenólicos intervino en la actividad de antioxidantes enzimáticos y no enzimáticos. Se encontró mayor capacidad antioxidante en hoja que en fruto, la cual se determinó por ABTS [2,2’-azino-bis (3-etilbenzotiazolin-6-ácido sulfónico)] y DPPH (1,1-difenil-2-picrilhidrazil). La inoculación de las plantas de tomate aumentó la actividad de las enzimas catalasa y fenilalanina amonio liasa en hoja; además, hubo reducción de la actividad enzimática del superóxido dismutasa y el contenido de fenoles totales. Conclusión. Los ácidos fenólicos intervinieron en los mecanismos de defensa enzimáticos de la planta y redujeron los niveles de estrés ocasionados por la inoculación

Efecto de los ácidos fenólicos en plantas de tomate ("Lycopersicon esculentum" Mill.) inoculadas con "Clavibacter michiganensis"

Con el objetivo de evaluar el efecto de aplicaciones exógenas de ácidos fenólicos en el cultivo de tomate, se establecieron cuatro tratamientos: 1) un testigo absoluto; 2) plantas inoculadas con Clavibacter michiganensis subesp. Michiganensis (Cmm); 3) plantas inoculadas con Clavibacter michiganensis subesp. michiganensis y con aplicación de ácidos fenólicos; y 4) plantas solo con aplicación de ácidos fenólicos. Las aplicaciones se realizaron con intervalos de una semana hasta acumular un total de 10 aplicaciones durante el ciclo de cultivo. Los resultados indican que la aplicación de ácidos fenólicos no promovió efectos en las variables agronómicas del cultivo, sin embargo, si se observó una disminución significativa en severidad de Cmm. Además, se demostró que la aplicación de ácidos fenólicos modifica la densidad e índice estomático y en combinación con estrés biótico induce un menor tamaño de estomas. En las variables histológicas se encontró que con la aplicación de ácidos fenólicos el parénquima empalizada disminuyó su longitud, también indujo un menor número y área de vasos de xilema en hoja y raíz respectivamente y una mayor longitud de córtex en la raíz. Los resultados demostraron que la aplicación de ácidos fenólicos puede ser una alternativa viable para el control de Cmm. Palabras clave: cambios histológicos, estomas, incidencia, severidad

Morfología y anatomía foliar de "Dasylirion cedrosanum" en diferentes etapas de desarrollo

In this paper was analyzed the foliar morpho-anatomy of Sotol Dasylirion cedrosanum Trel., perennial species northern Mexico and southern United States. This species is of great economic and social importance in arid and semiarid areas of Mexico. The objective was to observe the differences in morphological and anatomical leaf development at different ages. For morphological study plant samples 6, 30, 60 and 84 months of age they were taken. The middle portions of the longitudinal axis of leaves were collected at ages previously established and fixed in FAA. The samples were processed with conventional methods to obtain permanent slides. The leaf epidermis consists unistrate cells isodiametric form, the stomata are paracytic type, stomatal density, stomatal index shows values between 14.0-23.3% and stomatal cells density ranging from 46.8-65, stomata mm-2, the adaxial and abaxial surfaces do not exhibit dominance over one another. The palisade parenchyma up to 62% increases with age; the mesophyll is isolateral with brachisclereids extending from vascular bands. The vascular bundles are bands of three orders on which there prismatic crystals. Keywords: leaf; paracitic; stomata; stomatal density; stomatal indexEn el presente trabajo se analizó la morfo-anatomía foliar de sotol Dasylirion cedrosanum Trel., especie perenne del Norte de México y Sur de Estados Unidos de América. Esta especie es de gran importancia económica y social en las zonas áridas y semiáridas de México. El objetivo fue observar las diferencias en el desarrollo morfo-anatómico de la hoja a diferentes edades. Para el estudio morfológico se tomaron muestras de plantas de 6, 30, 60 y 84 meses de edad. Se colectaron porciones medias del eje longitudinal de las hojas en las edades previamente establecidas y se fijaron en FAA. Las muestras se procesaron con los métodos clásicos para la obtención de láminas permanentes. La epidermis foliar está formada por células unistratas de forma isodiamétrica, los estomas son de tipo paracítico, la densidad estomática, el índice estomático muestra valores entre 14.0-23.3% y la densidad de células estomáticas oscila entre 46.8-65, estomas mm-2, las superficies adaxial y abaxial no exhiben dominancia una sobre otra. El parénquima en empalizada se incrementa hasta 62% con la edad; el mesofilo es isolateral con braquiesclereidas que se prolongan desde las bandas vasculares. Los haces vasculares son bandas de tres órdenes sobre la que existen cristales prismáticos. Palabras clave: densidad estomática; estomas; hoja; índice estomático; paracític

Use of Chitosan-PVA Hydrogels with Copper Nanoparticles to Improve the Growth of Grafted Watermelon

Modern agriculture requires alternative practices that improve crop growth without negatively affecting the environment, as resources such as water and arable land grow scarcer while the human population continues to increase. Grafting is a cultivation technique that allows the plant to be more efficient in its utilization of water and nutrients, while nanoscale material engineering provides the opportunity to use much smaller quantities of consumables compared to conventional systems but with similar or superior effects. On those grounds, we evaluated the effects of chitosan-polyvinyl alcohol hydrogel with absorbed copper nanoparticles (Cs-PVA-nCu) on leaf morphology and plant growth when applied to grafted watermelon cultivar ‘Jubilee’ plants. Stomatal density (SD), stomatal index (SI), stoma length (SL), and width (SW) were evaluated. The primary stem and root length, the stem diameter, specific leaf area, and fresh and dry weights were also recorded. Our results demonstrate that grafting induces modifications to leaf micromorphology that favorably affect plant growth, with grafted plants showing better vegetative growth in spite of their lower SD and SI values. Application of Cs-PVA-nCu was found to increase stoma width, primary stem length, and root length by 7%, 8% and 14%, respectively. These techniques modestly improve plant development and growth

Incomplete penetrance in maize genotypes segregating for the polyembryony trait

To study the genetic control of polyembryony trait in maize germplasm a series of experiments were carried out.The genetic material came from crossings among two polyembryonic populations and 16 different genotypes,normal type maize. A total of 27 F1 were generated in 2016, and from those, there were derived 22 F2, and 20backcrosses genotypes. The experiments were carried out in two locations in Northern Mexico. Several genotypesin the second generation progenies share the same preceding F1. The theoretical expectations for polyembryony(PEm, in short) proportions in F2 and backcrossing are 0.0625 and 0.25, respectively. It is instructive to statethat given the PEm recessiveness, all the F1 genotypes were normal type plants: one seedling per germinatedseed. The statistical methods applied to the experimental data were the exact Binomial test, for the segregatingproportions in F2, and the exact Fisher test to prove for independence between environments and the PEm genotypes.There were used R procedures for calculations. Based on the results, we have concluded that 1) varyinggenetic backgrounds in crossings might have an impact on the trait segregation proportions depending upon thespecific parents’ genotypes, which eventually lead to a penetrance reduction of the PEm genes expression, 2)polyembryony frequencies of the two populations were always statistically the same, no matter the environmentalconditions where they were grown, and 3) the trait´s inheritance model was validated

Yield and quality of hybrid tomato grafted and cultivated under shade mesh and greenhouse

ABSTRACT. The objective was to determine the yield, fruit quality and root development of four grafted tomato hybrids grown under anti-aphid mesh cover and greenhouse. The grafted hybrids were grown under shade mesh and greenhouse from april to november 2014. Variables evaluated were: fruit weight per plant, number of clusters per plant, number of fruits per plant, polar and equatorial fruit diameter, vitamin C and lycopene contents, and root fresh and dry weight. Hybrids grafted and cultivated under anti-aphid mesh had higher quality than the production obtained under greenhouse. However, lycopene and vitamin C contents and accumulated root system dry matter are greater under greenhouse.RESUMEN. El objetivo fue conocer el rendimiento, calidad de fruto y desarrollo de raíz de cuatro híbridos injertados de tomate cultivados bajo cubierta de malla antiáfidos e invernadero. Los híbridos injertados se cultivaron bajo malla sombra e invernadero de abril a noviembre de 2014. Se evaluaron las variables: peso de fruto por planta, número de racimos por planta, número de frutos por planta, diámetro polar y ecuatorial del fruto, contenido de vitamina C y licopeno, y peso fresco y seco de raíz. Los híbridos injertados y cultivados bajo malla antiáfidos, tuvo mayor calidad que la producción obtenida bajo invernadero. Pero el contenido de licopeno, vitamina C y acumulación de materia seca del sistema radicular es mayor bajo invernadero

Efecto del portainjerto en el índice y densidad estomática de pimiento morrón Capsicum annuum var. annuum

The aim was to determine the effect of the rootstock and graft on the stomatal index and density of pepper chili. The treatments were grafted and ungrafted pepper, with five replicates. Stomatal density, index, length and width were determined with a Carl Zeeis microscope with an integrated camera and AxionVisionRel.4.8 measuring software. Significant differences were found in adaxial and abaxial stomatal density and index, with the grafted pepper surpassing the ungrafted pepper by 26.20, 21.07 and 8.74%, respectively. The ungrafted pepper surpassed the grafted pepper by 8.51% in density of abaxial epidermal cells, while the grafted pepper surpassed the ungrafted pepper by 8.64 and 11.22% in stomatal length and width, respectively. The rootstock increased the stomatal index and density of the surface and underside, as well as the size of stomata and epidermal cells of the underside, thereby modifying the physiological behavior of the plant.El objetivo fue determinar el efecto del portainjerto y del injerto en el índice y la densidad estomática del chile pimiento. Los tratamientos fueron, pimiento injertado y sin injertar, con cinco repeticiones. La densidad e índice estomático, largo y ancho de estomas se determinaron con un microscopio Carl Zeeis con cámara integrada y software de medición AxionVisionRel.4.8. Se encontraron diferencias significativas en densidad e índice estomático adaxial y abaxial, superando el pimiento injertado al sin injertar en 26.20, 21.07 y 8.74%, respectivamente. El pimiento sin injertar superó en 8.51% al injertado en densidad de células epidérmicas abaxiales, mientras que el largo y ancho de estomas del pimiento injertado superó en 8.64 y 11.22% al sin injertar. El portainjerto incrementó el índice y la densidad estomática del haz y del envés, tamaño de estomas y células epidérmicas del envés, modificando el comportamiento fisiológico de la planta

Seed Physiological Potential of Capsicum annuum var. glabriusculum Genotypes and Their Answers to Pre-Germination Treatments

Piquin pepper (Capsicum annuum var. glabriusculum) is an important species that supports the economy of rural households; it is part of Mexican gastronomy and it is a highly valuable phytogenetic resource. There has been recent interest in domesticating and exploiting piquin pepper commercially, which has been limited until now due to the low germination rate, and this work had the purpose of promoting germination and determining the physiological capacity of genotypes. Ten piquin pepper genotypes from different geographical origins in Mexico were submitted to 11 pre-germination treatments. A completely randomized experimental design was carried out with arrangement in split-plot. The large plot had the treatments and the small plot had the genotypes. The results showed differences (p < 0.01) among treatments, genotypes, and treatment–genotype interaction. On one hand, treatments gibberellic acid (GA) and mechanical scarification + gibberellic acid (MSGA) increased the physiological potential of genotypes, reaching the highest values of germination speed (GS), germination index (IG) and germination percentage (GP); as well as the lowest values of dead seeds (DS) and hard Seeds (HS). In turn, the genotypes that presented the same condition were G8, G7, and G10. Regarding the interaction, each variable had a different condition. In conclusion, we can increase the physiological potential and solve the dormancy of piquin pepper seed by applying gibberellic acid. Likewise, the best genotypes were G8 and G10