Flavonoids in Agriculture

Flavonoids are compounds that are secondary metabolites, but which play an important role in the biological activities of plants. They can be responsible for the color of flowers and fruits and for the attraction of pollinators. They also participate in plant-microorganism symbiosis. These relationships can be used to naturally control weeds and insect pests and reduce stress and diseases in order to increase crop yield. To improve the understanding of the different biological systems where flavonoids are involved in their symbiotic relationships and in plant physiology, tools such as metabolomics are used, which give a broader picture and allow to search for strategies to solve problems specific to the agricultural sector

Metabolomics as a Tool in Agriculture

Metabolomics is a study through can be obtain a better understanding of the complexity of the biological systems, through the chemical composition and relations with the physiology of the plant. The literature describes a lot of information on this support in areas of medicinal plants, chemosystematics, adulteration of plants, etc., but it is scarce in agriculture. At present, agriculture plays a crucial role in human beings. The demand of foods has increased due to the continuous increase in the population, and this requires an increase in the production of crops, besides the crops being affected by the climatic change, attack of pest and diseases and resistance to a conventional agrochemicals. At present, scientists are doing some practices or studies of genetic improvement of crops to increase their production and avoid the problems pointed out. It is an important part of the genomic studies; the results could be the basis for a genetic improvement based on the chemical composition of the crops, and in the metabolomics studies represent a crucial role in their quality for human consumption. The aim of the chapter is to review the literature from 10 years behind emphasizing the importance of metabolomics in crops of economic and feed value

Aromatic and Medicinal Plants in Mexico

Medicinal and aromatic plants in Mexico have been studied and explored through history. Day by day there is an increase in ethnobotanical, taxonomic, or phytochemical studies, providing an encouraging picture of research in Mexico and to support its use in traditional medicine. Chemical and biological exploration permit to provide solutions to the treatment of diseases. With this background, the objective of this chapter is to show the potential of endemic medicinal and aromatic plants in Mexico

Aislamiento e identificación de volátiles de Physalis philadelphica LAM

El objetivo de este trabajo fue aislar e identificar los componentes volátiles del tomate de cáscara Physalis philadelphica Lam. Por lavado con hexano, aireación dinámica (AD) y micro extracción en fase sólida (MEFS) se aislaron volátiles de P. philadelphica, los cuales se analizaron e identificaron por cromatografía de gases (CG) y CG acoplada a espectrometría de masas (CG-EM). Los compuestos recolectados por AD y MEFS se identificaron como salicilato de metilo, β-cariofileno, β-pineno, alcohol bencílico, 3-careno, β-elemeno, decanal y germacreno D. Los componentes recolectados lavando las plantas con hexano fueron β-cariofileno, linolenato de etilo, salicilato de metilo, β-pineno, ácido hexadecanoico, linolenato de metilo, alcohol bencílico, germacreno D, 3-careno, β-elemeno y decanal

Structural Characterization of Lignin in Four Cacti Wood: Implications of Lignification in the Growth Form and Succulence

Wood lignin composition strongly depends on anatomical features and it has been used as a marker for characterizing major plant groups. Wood heterogeneity in Cactaceae is involved in evolutionary and adaptive processes within this group; moreover, it is highly correlated to the species growth form. Here we studied the lignin structure from different types of woods in four Cactaceae species with different stem morphologies (Pereskia lychnidiflora, tree/fibrous wood; Opuntia streptacantha and Pilosocereus chrysacanthus, tree/succulent fibrous wood; Ferocactus hamatacanthus, cylindrical stem/dimorphic wood) in order to determine their relationship with the wood anatomy in an evolutionary-adaptive context. Dioxane lignin was isolated and analyzed by pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC/MS), two-dimensional nuclear magnetic resonance spectroscopy (2D-NMR) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The main linkages are the β-O−4′ ether (67–85%), the β-β′ resinol (10–26%) and the β-5′ and α-O−4′ linkages of the phenylcoumaran structures (≤7%). Spirodienone structures have a considerable abundance (5%) in the dimorphic wood of F. hamatacanthus. In addition, low contents (≤3%) of α,β-diaryl ether, α-oxidized β-O−4′ ether and dibenzodioxocin structures were found. The sinapyl- and coniferyl acetates are not part of the wood lignin in any of the studied species. The low (≤5%) γ-acetylation in the F. hamatacanthus and P. chrysacanthus wood lignin is here interpreted as an evidence of a high specialization of the wood elements in the conduction/storage of water. The lignin of the studied Cactaceae is composed predominantly of guaiacyl and syringyl units (S/G: 0.9–16.4). High abundance of syringyl units (62–94%) in three of the four species is considered as a defense mechanism against oxidative agents, it is a very conspicuous trait in the most succulent species with dimorphic wood. Furthermore, it is also associated with ferulates and the herein called γ-acetylated guaiacyl-syringaresinol complexes acting as nucleation sites for lignification and as cross-links between lignin and carbohydrates at the wide-band tracheid-fiber junctions

Efecto insectistático de extractos etanólicos de clavo y pimienta en Trialeurodes vaporariorum West. (Hemiptera: Aleyrodidae)

In the management the greenhouse whitefly, Trialeurodes vaporariorum, organosynthetic pesticides are commonly used, increasing the frequency and doses of application, thus generating resistance of the pest to pesticides and eliminating natural enemies. Then, this make necessary to search for alternatives that contribute to solve the whitefly problem without deteriorating the environment at must. Among several options, bioassays were established applying ethanol extracts of clove Syzygium aromaticum and pepper Pimenta dioica to the leaves of tomato plants where 2-day-old adults were released in a bioassay, and on another set of tomato plants oviposition was previously induced for 3 d. Mortality of adults and laid eggs, as well as hatched eggs were recorded. The 1.0% clove extracts caused 33.7 adult mortality, 72.9% oviposition inhibition with CIO50 of 0.19, and pepper extracts caused 32.5% adult mortality, 65.8% oviposition inhibition with CIO50´s of 0.46%, and both inhibited from 52.6 to 100% hatching with CIE50´s from 0.11 to 0.71% respectively, it being total when 1.0% pepper extract is applied to 2-day-old eggs. It is suggested that activity of the clove and pepper ethanol extracts is mainly insectistatic, although it can have an ovicide effect, it is a biorational input to be integrated into the ecological management of the greenhouse whitefly.En el manejo de la mosca blanca Trialeurodes vaporariorum generalmente se hace uso de plaguicidas organosintéticos, aumentando cada vez más la frecuencia y la dosis de aplicación, lo que provoca resistencia en la plaga a los plaguicidas y eliminación de enemigos naturales, por lo que es imprescindible la búsqueda de alternativas que contribuyan a resolver el problema, sin deterioro del ambiente. Entre las diversas opciones, en los bioensayos se aplicaron al follaje de tomate los extractos etanólicos de clavo Syzygium aromaticum y pimienta Pimenta dioica, en plantas donde previamente se liberaron adultos de 2 d y en otras plantas se indujo la oviposición por 3 d. En estos bioensayos se registró la mortalidad de adultos y huevos ovipositados, así como huevos eclosionados. Los extractos al 1.0% de clavo causan 33.7% de mortalidad de adultos, 72.9% de inhibición de oviposición con CIO50 de 0.19, y de pimienta causan 32.5% de mortalidad de adultos; 65.8% de inhibición de oviposición; con CIO50 0.46% y ambos extractos inhiben de 52.6 a 100% la eclosión de los huevos de mosca blanca con CIE50´s de 0.11 a 0.71% respectivamente, siendo total cuando se aplica el extracto de pimienta al 1.0% a huevos de 2 d de edad. La actividad de los extractos etanólicos de clavo y pimienta, principalmente insectistática; aunque puede llegar a tener efecto ovicida, es una aportación biorracional para integrarse al manejo ecológico de mosca blanca

Germinación diferencial asociada con viviparidad facultativa en Stenocereus thurberi (Cactaceae): correlaciones climáticas en poblaciones marginales de Sinaloa, México

Background and Aims: Precocious (viviparous) seed germination in fruits of Stenocereus thurberi has been correlated with higher germination rate of the remaining seeds. This study compares the germination of five populations from Sinaloa, Mexico, to determine: 1) whether there is a pattern associated with precocious seed germination and, 2) how much the viviparous phenomenon accounts for germination compared to variation between fruits, individuals and populations of the cactus.Methods: The incidence of vivipary was recorded in 194 plants, and seeds were separated into four putative sources of variance: populations, reproductive categories (VV: viviparous, NV: non-viviparous), individuals within categories and fruits within individuals. The seed germination response in percentage (PGF), mean time (TMG), rate (VG), and synchrony of germination (SG) was evaluated under a randomized complete blocks scheme with three replicates, in experimental units of 25 seeds. Data were analyzed with hierarchical ANOVAs for a linear mixed model.Key results: Reproductive categories accounted for 5-11% of variance and showed significant differences in favor of viviparous phenotypes, with PGF of 35 vs 19% and 91 vs 72%, VG of 1.5 vs 0.5 and 7.9 vs 5.4 seeds/day, and SG of 0.3 vs 0.1, 0.7 vs 0.5 and 0.8 vs 0.6. Buenavista and Tosalibampo populations showed higher percentage, rate and synchrony of germination than the other populations (P<0.05, Student t-test).Conclusions: There is a seed germination pattern associated to vivipary in S. thurberi. The variance accounted by this condition depends on the environment in which seed maturation and germination occur. The seeds from viviparous phenotypes showed higher germination vigor than seeds from non-viviparous plants, revealing potential for seedling recruitment and population growth under drought and salinity stress.Antecedentes y Objetivos: La germinación precoz (vivípara) de semillas en frutos de Stenocereus thurberi se ha correlacionado con mayor velocidad de germinación de las semillas remanentes. Esta investigación compara la germinación de cinco poblaciones de Sinaloa, México, para determinar: 1) si existe un patrón asociado con la germinación precoz de las semillas y 2) cuánto contribuye el fenómeno vivíparo a la germinación, dada la variación entre frutos, individuos y poblaciones de esta especie.Métodos: Se revisó el nivel de viviparidad de 194 plantas y se separaron las semillas en cuatro probables fuentes de varianza: poblaciones, categorías reproductivas (VV: vivíparas y NV: no vivíparas), plantas dentro de categorías y frutos dentro de plantas. Las respuestas de germinación final (PGF), tiempo medio (TMG), velocidad (VG) y sincronía de germinación (SG) se evaluaron en bloques al azar con tres repeticiones, en unidades experimentales de 25 semillas. Los datos se analizaron con ANOVA’s jerárquicos bajo un modelo lineal mixto.Resultados clave: Las categorías reproductivas explicaron 5-11% de la varianza y mostraron diferencias significativas a favor de las vivíparas, con PGF de 35 vs 19% y 91 vs 72%, VG de 1.5 vs 0.5 y 7.9 vs 5.4 semillas/día, y SG de 0.3 vs 0.1, 0.7 vs 0.5 y 0.8 vs 0.6. Las poblaciones de Buenavista y Tosalibampo tuvieron mayor porcentaje, velocidad y sincronía de germinación (prueba t de Student, P<0.05) que las otras poblaciones.Conclusiones: Existe un patrón de germinación asociado con viviparidad en S. thurberi. La varianza asociada con esta condición depende del ambiente de maduración y germinación de las semillas. Los fenotipos vivíparos germinaron con mayor vigor que los no vivíparos, mostrando potencial para apoyar la incorporación de individuos y el crecimiento de la población en condiciones de estrés hídrico y salino

Biosynthesis of Silver Nanoparticles Using Chenopodium ambrosioides

Biosynthesis of silver nanoparticles (AgNPs) was achieved using extract of Chenopodium ambrosioides as a reducer and coating agent at room temperature (25°C). Two molar solutions of AgNO3 (1 mM and 10 mM) and five extract volumes (0.5, 1, 2, 3, and 5 mL) were used to assess quantity, shape, and size of the particles. The UV-Vis spectra gave surface plasmon resonance at 434–436 nm of the NPs synthesized with AgNO3 10 mM and all extract volumes tested, showing a direct relationship between extract volumes and quantity of particles formed. In contrast, the concentration of silver ions was related negatively to particle size. The smallest (4.9 ± 3.4 nm) particles were obtained with 1 mL of extract in AgNO3 10 mM and the larger amount of particles were obtained with 2 mL and 5 mL of extract. TEM study indicated that the particles were polycrystalline and randomly oriented with a silver structure face centered cubic (fcc) and fourier transform infrared spectroscopy (FTIR) indicated that disappearance of the –OH group band after bioreduction evidences its role in reducing silver ions

Biosynthesis of silver nanoparticles using chenopodium ambrosioides

ARTICULO INDEXADOBiosynthesis of silver nanoparticles (AgNPs) was achieved using extract of Chenopodium ambrosioides as a reducer and coating agent at room temperature (25∘C). Two molar solutions of AgNO3 (1 mM and 10 mM) and fie extract volumes (0.5, 1, 2, 3, and 5 mL) were used to assess quantity, shape, and size of the particles. Th UV-Vis spectra gave surface plasmon resonance at 434– 436 nm of the NPs synthesized with AgNO3 10 mM and all extract volumes tested, showing a direct relationship between extract volumes and quantity of particles formed. In contrast, the concentration of silver ions was related negatively to particle size. Th smallest (4.9 ± 3.4 nm) particles were obtained with 1 mL of extract in AgNO3 10 mM and the larger amount of particles were obtained with 2 mL and 5 mL of extract. TEM study indicated that the particles were polycrystalline and randomly oriented with a silver structure face centered cubic (fcc) and fourier transform infrared spectroscopy (FTIR) indicated that disappearance of the –OH group band aftr bioreduction evidences its role in reducing silver ions.CCIQS; “Fideicomiso Revocable y de Administracion no. 157304´ COLPOS” and the L´ınea de Investigacion Prioritaria LPI-16´ “Innovacion Tecnol´ ogica” at the “Colegio de Postgraduados´ COLPOS