El chile Manzano o Cera (Capsicum pubescens), es una planta perenne originaria de las tierras altas de América del Sur. Durante su almacenamiento, el principal problema que presenta es su testa, lo cual ocasiona una disminución de la germinación en condiciones naturales. Debido a que existe poca información sobre la germinación, es necesario implementar alternativas que garanticen el recurso dentro de un programa de mejoramiento genético. El objetivo fue evaluar el efecto de ácido sulfúrico (H2SO4), peróxido de hidrógeno (H2O2) y ácido giberélico-3 (C19H22O6) sobre el porcentaje de emergencia y características de plántulas de semillas de C. pubescens. El experimento se realizó en la Unidad de Manejo y Conservación de Recursos Genéticos de la Facultad de Ciencias Biológicas y Agropecuarias de la Universidad Veracruzana. Se utilizaron semillas de C. pubescens provenientes de la localidad de Huatusco, Veracruz, México, almacenadas a temperatura ambiente durante un año. Los tratamientos estudiados fueron: inmersión en H2SO4 (100, 75, 60 %; 30 min); inmersión en H2O2 (20, 10, 15 %; 15 min), inmersión en C19H22O6 (25, 20, 15 mg; 24 h) y el tratamiento testigo. Los resultados en el presente estudio revelan diferencias estadísticas significativas (P ≤ 0,01) para todas las variables evaluadas. El mejor porcentaje de germinación se provocó con inmersión en C19H22O6 (15 mg; 24 h) y H2O2 (20 %; 15 min). El tratamiento con H2SO4 fue perjudicial ya que no hubo emergencia.

Dioon holmgrenii De Luca, Sabato et Vázq.Torres is an endangered species; it is endemic and its distribution is restricted to the biogeographic province of the Mexican Pacific Coast. The aim of this work was to determine the diversity and genetic structure of nine populations. The genetic diversity parameters and Wright’s F statistics were determined with six microsatellite loci. The genetic structure was determined by using the Structure software and by a discriminant analysis. The genetic diversity of the populations was high. The proportion of polymorphic loci was 0.89, the observed heterogeneity was higher (Ho = 0.62 to 0.98) than expected (He = 0.48 to 0.78), and the fixation index was negative (IF = −0.091 to −0.601). Heterozygous deficiency (FIT = 0.071) was found at the species level and heterozygotes excess (FIS = −0.287) at the population level. The genetic differentiation between populations was high (FST = 0.287), with the number of migrants less than one. Three groups of populations were differentiated, and the variation within populations, between populations, and between groups was: 65.5, 26.3, and 8.2%, respectively. Multiple factors explain the high genetic diversity, while the genetic structure is due to geographic barriers. Community reserves are urgent in at least one most diverse population of each group.

Characterizing the genetic diversity of maize (Zea mays L.) populations by their morphological and molecular attributes makes it possible to place populations into specific groups; thus, facilitating the design of procedures for their optimum and sustainable use. In this study, data from two lines of evidence were analyzed simultaneously to robustly classify maize populations and to determine their genetic relationships. Seven maize races of the central high plateau of Mexico were characterized using a combined analysis of 13 morphological traits and 31 microsatellite loci. The germplasm assessed included samples of 119 accessions held at Mexican germplasm banks. Cluster and principal component analyses were performed. Also, genetic and geographic relationships among the accessions were determined. Principal component analysis separated the different accessions into well-defined groups using first three principal components. The accessions of Arrocillo Amarillo and Elotes Cónicos races did not exhibit a grouping pattern, indicating greater genetic complexity. Better grounded grouping and phylogenetic relationships were obtained when traits of both lines of evidence were used simultaneously.

La calidad del rastrojo de maíz es un aspecto importante para mejorar su consumo en rumiantes y poco se conoce sobre su variación en la diversidad de variedades cultivadas en el altiplano mexicano. El objetivo fue conocer la calidad del rastrojo (hoja) en poblaciones nativas de maíz en dos regiones del altiplano Poblano-Tlaxcalteca. Por cada región, en dos localidades se ensayaron 144 cultivares, de los cuales 134 fueron poblaciones nativas y seis cultivares comerciales recomendados para zonas templadas. Se cuantificó la digestibilidad in vitro, fibra detergente neutro, fibra detergente ácido, precocidad, rendimiento de forraje y grano. El diseño experimental fue un látice simple 12x12 con dos repeticiones. En ambas regiones se encontraron diferencias en digestibilidad (p< 0.01) entre cultivares en un intervalo de 10 unidades porcentuales. Las variedades locales sobresalientes fueron las que presentaron la mayor digestibilidad (62.8 y 57.7% promedios por región) que los cultivares comerciales (57.3 y 57.7%), variable que se asoció a menores concentraciones de fibra insoluble en detergente neutro (68.8 y 75.7% vs 71.7 y 78.3%), principalmente. Tanto la precocidad, la coloración del grano o el rendimiento del grano no se asociaron con la digestibilidad. En conclusión, existe diversidad en la digestibilidad de la hoja en rastrojo entre cultivares, algunas variedades locales tuvieron mayor digestibilidad que los híbridos comerciales ensayados. Las diferencias en digestibilidad se relacionaron a diferencias en la concentración de fibra detergente neutro donde las variedades comerciales tendieron a ser más fibrosas. Algunas variedades locales sobresalientes en digestibilidad tuvieron alta producción de grano y rastrojo.

Background: Bacopa procumbens is a plant species with medicinal properties. Although several of these properties have already been validated, its use for treating pain remains untested. Objective: the objective was therefore to test the antinociceptive effect of two extracts (n-hexane and hydroalcoholic) and two fractions (aqueous and organic) from the most active extract, as well as to determine the chemical profile of Bacopa procumbens. Methods: analgesic activity was determined by antinociceptive activity using the formalin model in mice. Compounds were identified by high-performance liquid chromatography and gas chromatography coupled with mass spectrometry. Compared to the vehicle treatment (3% Tween 20), licking time was 22.8 s and 141.6 s lower when treated with the hexane extract (200 mg/kg); 43.4 s and 152.5 s with the hydroalcoholic extract (200 mg/kg); 27.2 s and 169 s with the organic fraction; and 5.4 s and 32 s difference with the positive control, in phases 1 and 2, respectively. Phytochemical analysis of the hexane extract allowed us to identify 2-pentadecanone, 6,10,14-trimetil- (11.70%), 6,10,14-trimethyl-, dibutyl phthalate (34.71%), and hexane-dioic acid bis(2-ethylhexyl) ester (45.15%). Conclusions: We identified arbutin (1), 5-(p-hydroxybenzoyl) shikimic acid (2), and procumgastrodin A (3) in the BpFo fraction. In conclusion, we demonstrated that the BpH extract and the BpFo fraction have anti-nociceptive properties that may be associated with compounds 2 and 3.

Ancho (width) chile peppers have economic, social, culinary and cultural importance in Mexico and worldwide. This chile type considers divergent subtypes that altogether have not been analysed and therefore their morphological diversity has not been systematically described. The objectives were to describe the morphological diversity of ancho pepper landraces from Mexico, to identify groups of similarity and to define the traits with the higher contribution to the total variation. Eighty-six landraces of ancho chile peppers (red, ‘mulatos’, ‘miahuatecos’, ‘cristalinos’ and ‘huacle’), collected in six states of Mexico, and two commercial controls were evaluated in two localities, in a simple randomized complete block experimental design. We recorded 76 morphological traits. Statistical analysis included a combined ANOVA, Pearson's correlation coefficient, discriminant analysis, principal components and clusters. The morphological diversity in ancho chile peppers was mainly made up of fruit width, fruit wall thickness, stem diameter, corolla length, seed weight per fruit, plant height, stem length and pubescence. We defined four groups, which made it possible to differentiate ancho chile peppers of Puebla and the huacle chile pepper of Oaxaca from populations collected in the north and ‘Bajío’ (midland) parts of Mexico. Ancho chile peppers of Mexico showed wide morphological differences according to the type of chile pepper and seed collection regions. The traits that contributed the greatest morphological diversity were fruit width, fruit wall thickness, stem diameter, corolla length, seed weight per fruit, plant height, stem length and pubescence.