Exposure to heavy metals has been documented to induce changes in the expression of plant proteins. Phaseolus vulgaris L., represents a great source of nutrition for millions of people, and is the second most important legume crop. The present study aimed to investigate the effects of Hg stress on germination rate and identify the gene expression profiling of U1-70 kDa by using SDS-PAGE analysis. Seeds of black beans (P. vulgaris L.) variety Jamapa were used. The study was performed in the municipality of Guadalupe in Zacatecas, México; August 2009 to 2011. Embryos were exposed to 10 µmol L-1 HgCl2. Expression and detection of U1-70 kDa was affected by mercury. It was possible to amplify the cDNA for U1-70 kDa in all tested samples, there were also found variations in the mRNA of embryos bean seeds for western blot analysis. Mercury does not affect the germination of bean seeds P. vulgaris L.; there is variation in the expression of the U1-70 kDa protein at different hours of exposure to 10 µmol L-1 of mercury. The presence of U1-70 kDa is identified for the first time in early stages of germination of bean seeds P. vulgaris L.

Abstract Agave angustifolia has a wide morphological variation, which often makes its taxonomy difficult. The differentiation between Agave species is made from homologous and independent morphological characteristics, whose variation can be ontogenetic and genetic. The objective of this research was to characterize the morphology of A. angustifolia called ‘sacatoro’ from the state of Guerrero. The research was conducted from 2016 to 2017, in six populations of A. angustifolia and two populations as control, A. angustifolia Haw and A. cupreata. 32 stem and leaf variables of mother plants and shoots were measured for each specimen, according to the technical guide for the varietal description of Agave spp. The data were analyzed using main components (ACP) and hierarchical agglomerative grouping (AJA). The variables that allowed to discern the populations were: shape, edge, color and texture of the leaf, striae on lateral spines and length of the terminal spine, all with a positive correlation. The results obtained from the ACP and the AJA allowed observing the relationship between variables and specimens based on the morphological attributes shared by the species studied. Despite the morphological variation between maguey sacatoro and A. angustifolia Haw, a close positive relationship between both is shown. So, it is inferred that the phenotypic characteristics that subgrouping the maguey sacatoro, could show as a result a possible variant of A. angustifolia Haw that would allow to locate taxonomically this group to contribute to the ordering of the Agave genus and its conservation.

Resumen El Agave angustifolia presenta una amplia variación morfológica, que con frecuencia dificulta su taxonomía. La diferenciación entre las especies de Agave, se hace a partir de características morfológicas homólogas e independientes entre sí, cuya variación puede ser ontogenética y genética. El objetivo de esta investigación fue caracterizar la morfología del A. angustifolia denominado ‘sacatoro’ del estado de Guerrero. La investigación se realizó de 2016 a 2017, en seis poblaciones de A. angustifolia y dos poblaciones como control, A. angustifolia Haw y A. cupreata. Se midieron 32 variables del tallo y hojas de plantas madre e hijuelos a cada ejemplar, de acuerdo con la guía técnica para la descripción varietal de Agave spp. Los datos se analizaron mediante componentes principales (ACP) y agrupamiento aglomerativo jerárquico (AJA). Las variables que permitieron discernir las poblaciones fueron: forma, borde, color y textura de la hoja, estrías en espinas laterales y longitud de la espina terminal, todas con una correlación positiva. Los resultados obtenidos del ACP y el AJA permitieron observar la relación entre variables y especímenes en función de los atributos morfológicos que comparten las especies estudiadas. A pesar de la variación morfológica entre el maguey sacatoro y el A. angustifolia Haw., se muestra una estrecha relación positiva entre ambos. Por lo que se infiere que las características fenotípicas que sub agrupan al maguey sacatoro, pudieran mostrar como resultado una posible variante de A. angustifolia Haw que permitiría ubicar taxonómicamente a este grupo para contribuir a la ordenación del género Agave y su conservación.

Abstract: The nutritional contents of guava flour and germinated guava seeds were evaluated. A proximal analysis and in vitro digestibility were performed. There were significant differences between the flour and germinated guava seeds (p <0.01) for a percentage of ash, crude protein, crude fiber and neutral detergent fiber. In the in vitro digestibility, the highest gas production was given by germination, with 40 ml of gas per 200 mg of dry matter. The highest production of volatile fatty acids after in vitro digestibility (48 h) occurred in the germination of guava seed. Basing on these results, it is concluded that the flour and germinated guava seeds have the possibility of being used in the diet of ruminants.

Resumen: Para evaluar los contenidos nutricionales de la semilla de guayaba se emplearon harina y germinado de la semilla. Se realizó un análisis proximal y digestibilidad in vitro. Existieron diferencias significativas entre la harina y germinado de semilla de guayaba (p<0.01) para porcentaje de ceniza, proteína cruda, fibra cruda y fibra detergente neutra. En la digestibilidad in vitro la mayor producción de gas se dio en germinado, con 40 ml de gas por cada 200 mg de materia seca. La mayor producción de ácidos grasos volátiles después de la digestibilidad in vitro (48 h) ocurrió en el germinado de semilla de guayaba. Se concluye que la harina y germinado de semilla de guayaba tienen posibilidad de ser utilizadas en la dieta de rumiantes.

Abstract The aim of this project was to evaluate the in vitro nutrient profile of Agave salmiana (AS) and Agave weberi cela (AWC) bagasse as alternative feedstuffs for ruminant nutrition. The bagasse was collected in Jalpa, Zacatecas during 2010. From collected samples, dry matter (DM), ash, crude fiber (CF), ether extract (EE), crude protein (CP), total organic carbon (TOC), neutral detergent fiber (NDF), and total reducing sugars (TRS) were evaluated. Macro- and micro-minerals were determined by atomic absorption spectroscopy. Also, it was used an in vitro gas production technique to evaluate fermentation kinetic, and after 48h of incubation samples were used to quantified VFA production. Crude protein (%) (2.25 vs 2.73), EE (%) (0.274 vs 0.272), CF (%) (22.15 vs 16.58) and ash (%) (2.14 vs 1.81) were not different statistically (p> 0.05) between AS and AWC treatment. Values for NDF (% DM) were statistically different (p< 0.05) between AS (45.45) and AWC (52.95) treatments. No differences on VFA’s were observed among agave bagasse and bean straw. Calcium (%) values averaged 3.46 and 1.95 for AS and AWC-treatments, respectively. It is concluded that Agave bagasse can represents an alternative feedstuffs for ruminants, especially at dry season.

Resumen El objetivo de este trabajo fue evaluar el perfil in vitro de nutrientes de bagazo de Agave salmiana (AS) y Agave weberi cela (AWC) como alternativa para la nutrición de los rumiantes. El bagazo se recogió en Jalpa, Zacatecas durante el año 2010. A partir de las muestras recogidas, se evaluó: materia seca (MS), cenizas, fibra cruda (FC), extracto etéreo (EE), proteína cruda (PC), carbono orgánico total (TOC), detergente neutro de fibra (DNF), y azúcares reductores totales (ART). Macro y micro-minerales se determinaron por espectroscopia de absorción atómica. Además, se utilizó una técnica de producción de gas in vitro para evaluar la cinética de fermentación, y después de 48 h de incubación de las muestras se utilizaron para cuantificar la producción de AGV. La proteína cruda (%) (2.25 vs 2.73), EE (%) (0.274 vs 0.272), CF (%) (22.15 vs 16,58) y cenizas (%) (2.14 vs 1.81) no fueron diferentes estadísticamente (p> 0.05) entre AS y tratamiento AWC. Los valores de DNF (% MS) fueron estadísticamente diferentes (p< 0.05) entre el AS (45.45) y los tratamientos AWC (52.95). No se observaron diferencias en AGV entre bagazo de agave y de frijol. Los valores de calcio (%) promedio de 3.46 y 1.95 para AS y AWC, respectivamente. Se concluye que, el bagazo de agave representa una alternativa viable para la alimentación de rumiantes, especialmente en la estación seca.