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This study presents the results of acid-thermal pretreatments and enzymatic saccharification for the production of fermentable sugars from the juice and bagasse of Agave salmiana leaves. In the acid-thermal pretreatment, H2SO4 was used while in the enzymatic saccharification the commercial enzyme Cellic Ctec2 (Novozyme) was used. In the results it was found that the best conditions of the acid thermal pretreatment (H2SO4 % (v/v) at 100 ° C for 30 min) for the juice generated a concentration of 43.65 ± 1.36 g/L of reducing sugars. In bagasse, the best conditions (H2SO4 % (p/v) at 120 ° C for 60 min) produced a concentration of 37.35 ± 1.65 g/L of reducing sugars in the hydrolysates. In the enzymatic saccharification at 15 FPU/g substrate and solids load of 10 % (p/v), a concentration of 87.37 ± 1.27 g/L of reducing sugars was obtained after 72 h. The results obtained demonstrate the potential of the integral use of bagasse and juices from the leaves of Agave salmiana as raw material to produce fermentable sugars.

En esta nota reportamos el consumo del fruto y dispersión no endozoócora de semillas de una especie vegetal que no había sido mencionada en la dieta de los murciélagos, y que no presenta las características típicas de quiropterocoria. Este evento fue registrado mientras realizábamos capturas nocturnas con redes de niebla, en fragmentos de vegetación secundaria en el área metropolitana de la ciudad de Xalapa de Enríquez, México. Un ejemplar hembra de Artibeus toltecus, capturada en junio de 2018, llevaba consigo dos frutos de Hoffmannia excelsa (Rubiaceae). Aunque H. excelsa es un arbusto común en el centro de Veracruz, éste es el primer registro conocido de dispersión en esta especie, llevada a cabo por murciélagos. El consumo de este fruto, con características ornitócoras, posiblemente obedece a una situación de oportunismo frente a un recurso temporalmente abundante.

Production of cacao and its products such as chocolate generate a global market. Despite demand, production has declined in a region historically important in the domestication of cacao in Mesoamerica. Chontalpa in southeast Mexico is an important area for cacao agroforestry systems, but a number of factors have affected current production, resulting in the elimination of many agroforestry systems. This study analyzes land use changes in the cacao production region of Tabasco State of SE Mexico using Landsat images from 2003 to 2016 to evaluate whether changes in cacao agroforestry systems into other land use forms are related to land tenure and distance to urban centers. Our results determined that land use changes were significantly lower in ejido lands, compared to other types of land tenure. A shorter distance to urban centers was associated with a higher probability of changing from cacao agroforestry systems to other land uses (grasslands, urban constructions). Members of young generations in the Chontalpa tend to move to urban centers that are continually growing at the expense of other land uses. Therefore, cacao agroforestry systems close to urban areas are more likely to change into this type of land use.

In this work, series of sequential acid-alkaline and enzymatic saccharification treatments were applied on lignocellulosic biomass of Agave salmiana leaves in order to evaluate its conversion into simple sugars. The effects of a catalytic reagent and residence time were evaluated on lignocellulosic biomass. Also, several levels of FPU and cellulose loadings on the treated biomass were applied in the enzymatic saccharification. Upon completion of an acid-alkaline pretreatment, the resulting hemicellulose was completely hydrolyzed, whereas that lignin removed and the remaining cellulose reached values of 91 and 84% (w/w) respectively. The liquid by-product after acid pretreatment had a content of 0.50 g/L of glucose, 1.87 ± 0.045 g/L of arabinose, 21.35 g/L of xylose, and 39.15 g/L of reducing sugars. The saccharification process reached yields of 93.11% of conversion and glucose concentrations of 49.76 g/L. The sequential process was highly efficient in releasing simple sugars with concentrations of up to 88.91 g/L. This study provides data to improve the conversion processes of lignocellulosic components A. salmiana leaves into simple sugars, and illustrates the potential of using this crop's residue as a feedstock for biofuel production.

Wetlands play important roles that benefit social-ecological systems. They are threatened by climate change and human activities, i.e., raising livestock and wildlife hunting. The latter is essential for subsistence and for the food security of rural communities. To understand the traditional uses of wildlife, we examined the use of wildlife among people living within and outside of, but close to wetlands, in the communities located in four municipalities of Veracruz, Mexico, using open-ended interviews. We also analyzed the socioeconomic factors and environmental problems associated with the use of wildlife, and how these affect food security. People, especially those living within the wetlands, use wildlife mainly for food and trade. Wildlife is mainly used as food but also as pets, ornaments and medicine. The most useful species were black-bellied whistling duck (Dendrocygna autumnalis), nine-banded armadillo (Dasypus novemcinctus) and Meso-American slider (Trachemys venusta). People living within the wetland make more intensive use of wildlife. The main problems causing decreasing wildlife populations were water pollution, hunting practices and deforestation. Local communities were aware of the importance of wetlands, their degradation and the need to preserve them. More research focused on socioecological systems is required to address both the need for biodiversity conservation and food security. Also, good local management plans that incorporate current knowledge about key species have to be drawn up with the participation of government and scientific institutions, citizens and local stakeholders.

The fungus Fusarium oxysporum f. sp. vanillae is the cause of stem and root rot in Vanilla planifolia, the most devastating disease of this crop. As part of a biotechnological breeding program to obtain vanilla genotypes resistant to this pathogen, we evaluate here the phytotoxic effects of culture filtrates of F. oxysporum f. sp. vanillae during the multiplication and rooting of plantlets of V. planifolia. In this research, the in vitro phytotoxicity of culture filtrates of three strains of the fungus together with their capacity to synthesize fusaric acid was evaluated. The median lethal dose (LD50) of the strains was determined by adding various concentrations of the fungal culture filtrates by means of in vitro cultivation of vanilla and calculating the percentage survival at the multiplication and rooting stages. The drastic decrease in the survival percentages of explants, denotes that only the H3 strain has phytotoxic effects in the two phases (multiplication and rooting) in vitro culture of V. planifolia. The strain H3 produced the highest level of fusaric acid (FA). During the multiplication phase and rooting, the FA level was inversely correlated with the survival of shoots. This study contributes to future programs of in vitro selection of vanilla genotypes resistant to this pathogen.

A large part of the natural vegetation in the tropics has been replaced by pastures and crop fields. To evaluate the value of mango orchards in the conservation of phyllostomid bats in a fragmented, heterogeneous landscape in Veracruz, Mexico we compared species richness, total abundance, dominance, evenness and abundance per feeding guild of bats in mango polycultures, mango monocultures and in semi-deciduous seasonal forest. Using mist nets at ground level, we captured 882 phyllostomid bats belonging to 17 species. Bat species richness was similar between the mango orchards and the forest, but the number of bats was significantly higher in mango polycultures, followed by mango monocultures and the forest. The frugivore guild was the most numerous in the mango orchards. Sanguivores were notably more numerous in the forest. Our results suggest that both types of mango orchards are different from the forest, since they are characterized by differences in bat species composition and feeding guild. We conclude that mango agroecosystems, when small in size and close to the forest, are important in the conservation of bats; it is there where bats are abundant and maintain a level of species richness similar to that of the original vegetation.

For birds, we tested the efficacy of a technique used to obtain faecal samples and their seed content from bats by placing plastic sheets below mist nets. This method was compared with that of collecting faecal samples using cotton bags. Plastic sheets were placed below each of eight mist nets to obtain faecal samples from birds caught in cloud forest remnants. Each bird was then placed separately in a cotton bag to catch any other seeds excreted. There were 84 faecal samples in total: 64 with no seeds and 20 with seeds; of the latter 65% were obtained from the plastic sheets. A total of 407 seeds were collected, 317 from 11 plant species were collected on the plastic sheets and 90 belonging to six plant species in the bags. Seed richness and abundance were significantly greater for samples obtained using the plastic sheets than with the cotton bags. Although the number of bird faecal samples obtained did not differ between methods (13 vs 7), with the plastic sheets the number of faecal samples with seeds increased. Thus, to obtain more representative faecal samples from frugivorous birds, we strongly recommend the use of plastic sheets as part of the technique.

Recently it was proposed that Centurio senex specializes on hard fruit because of its strong bite compared to other similar-sized frugivorous bats; however, this hypothesis has not been tested. We tested the hardness of 5 fruit species eaten by bats, including Sideroxylon capiri (Sapotaceae), here reported for the 1st time as part of the diet of C. senex. Results show that S. capiri is the hardest fruit of the species evaluated. This is the 1st evidence of C. senex eating hard fruit in the wild, which supports the theory of a skull adapted to eating hard fruit.

Studies comparing the abundance of frugivorous bats in shade-coffee plantations and forest fragments report contradictory results, and have not taken into account the landscape context in which coffee plantations are immersed. Variables of population composition such as abundance, sex proportion, and reproductive condition, together with biological tags (i.e., bat fly prevalence), can provide information about spatiotemporal dynamics of habitats used by bats. In the central part of Veracruz, Mexico, we compared population variables and ectoparasite prevalence of the highland yellow-shouldered bat (Sturnira ludovici) in two landscapes, one dominated by shade-coffee plantations and another by forest fragments. Comparing these attributes between these two landscapes will increase our knowledge about the role of this agro-ecosystem in the conservation of this species, which is an important seed disperser of cloud forest vegetation. Total abundance and proportion of females was greater in forest fragments than in coffee plantations, whereas the percentage of reproductive females and bat fly prevalence was similar between landscapes. Our results show that landscapes with forest fragments harbor the greatest abundance of S. ludovici, but shade-coffee plantations also are utilized by S. ludovici and likely adjacent forest remnants provide enough food resources for this species and other frugivores. Moreover, this study provides more evidence documenting the importance of preserving the last cloud forest fragments in the central region of Veracruz, Mexico, and suggests that using shade-coffee plantations to connect forest fragments may be an effective way of maintaining populations of S. ludovici and likely other volant frugivores.

Frugivorous bats respond differently to changes in the landscape, depending on their morphological and ecological characteristics, so only some species cross deforested areas and disperse seeds in these environments. In this study we analyzed the plant species dispersed by bats in tropical rain forest and patches of secondary vegetation of a forest reserve in Mesoamerica. We expected that the most common bat species in secondary vegetation would be the most important dispersers, favoring the regeneration of vegetation, compared to those that forage mainly in tropical forest. With a capture effort of 5520 net hours, we caught 1718 bats representing 16 frugivorous species. Based on the analyses of fecal samples the most common plants in the bats' diets were pioneer species, mainly from the families Piperaceae, Urticaceae, Solanaceae, Fabaceae, and Muntingiaceae. The most important bat species to seed dispersal in the secondary vegetation were Carollia sowelli, Sturnira lilium, Glossophaga soricina and Carol...

We evaluated how the abundance and richness of frugivorous and nectarivorous bat species differs among three types of common agroecosystems (diversified coffee plantations, simple coffee plantations and pastures) in Veracruz, Mexico, that represent a gradient of structural and floristic complexity. Using mixed effects models we demonstrated that both the richness and the total abundance of bats was higher in the diversified coffee plantations. We detected similar patterns on comparing the abundance of the four most abundant bat species. Neither season nor the season-agroecosystem interaction had any effect on the comparisons made. Using multiple regressions we found that the richness of plants that are useful to both people and bats had the most explanatory power for the richness and total abundance of frugivorous and nectarivorous bats, as well as for the abundance of Carollia sowelli, Glossophaga soricina and Sturnira spp. Our results indicate that agroecosystems value for conservation of fruit and nectar-eating bats increases as the fruit-bearing trees increases. For the effective conservation of these guilds of bats in tropical agroecosystems, a strategy of diversification with fruit-bearing species is highly recommended; such a strategy would benefit both agricultural producers and wildlife.

The aim of this study was to compare the diversity of small rodents along four unequally disturbed habitats in a low deciduous forest in Dzilam de Bravo, Yucatan: an abandoned pastureland (AP) with five-year old (SCA), ten-year old (SDA), and more than ten-year old (SMD) forests. A total of 478 rodents were captured with 1,754 recaptures from May 2005 to April 2006. They were included in six species and two families. Our work was done in two grids of 5,000 m 2 with a distance of 10 m between rows and columns; Sherman’s traps were set two nights per month in all sites. The habitat with the highest diversity (H’= 1.328) and specific richness was the site with the highest disturbance and the lowest diversity (H’= 0.6321) (PA), but the highest abundance was in the SMD forest. Differences in diversity among sites were significant ( P < 0.05), except between SCA and SDA forests. The abundance values differed strongly in all sites. The abundance patterns of O. phyllotis were influenced by a disturbance gradient due to human influence and topography of the area, factors associated to the diversity observed.

Under the hypothesis that bat diversity would be lower in the early stages of secondary succession and that species affected negatively by habitat modification would be more frequent in later successional stages, we evaluated how bats use 12 vegetation stands representing four stages of secondary succession, following disturbance caused by slash-and-burn agriculture and selective logging. We compared bat richness, abundance and diversity, and found that none of these variables was different among stages or rainy seasons. However, of the 10 most common bat species, two were significantly more abundant in stands at the early stages of secondary succession, while the opposite was true for three other species. Canopy cover mainly explains these patterns. Rainy season had no effect on the abundance of the common species. The results of this study indicate that although some frugivorous species were very abundant in the younger stands, the majority of the rare species were captured in older stands. The absence of rare and habitatspecialized species from young successional stages close to primary forest suggests that, for effective bat conservation in landscapes modified by human activity, areas with original vegetation should be maintained to ensure the survivorship of sensitive-to-deforestation species.

With the aim of quantitatively evaluating the usefulness of phyllostomid bats as ecological indicators, we compared intra-family levels and feeding guilds between tropical old-growth forest and patches of secondary vegetation growing where the land had been used for shifting agriculture. There were significant differences between vegetation types in bat species composition, with the frugivore guild most abundant in secondary vegetation and the animalivore guild most abundant in the old-growth forest. These results are congruent with the findings for other Neotropical zones and appear to be associated with the type of soil management that allows secondary vegetation to grow. Using the Indicator Value method, two subfamilies, five genera and five species were found to have a significant indicator value. However, these numbers only represent a small proportion of the five subfamilies, 20 genera and 28 species recorded, indicating that under the disturbance conditions that characterize the study area...

We report the dispersal of Conostegia xalapensis (Melastomataceae) and Coussapoa oligocephala (Urticaceae) seeds by Underwood's long-tongued bat, a species considered to be a specialized nectar and pollen consumer. Informamos la dispersion de semillas de Conostegia xalapensis (Melastomataceae) y Coussapoa oligocephala (Urticaceae) por el murcielago de lengua larga de Underwood, una especie considerada como consumidora especializada en nectar y polen.

De mayo de 2005 a abril de 2006 se monitorearon pequeños roedores en cuatro sitios que representaron un gradiente de perturbación en Dzilam de Bravo y localidades aledañas: Pastizal abandonado (PA), selva baja caducifolia de cinco años (SCA), selva de hasta diez años (SDA) y selva de más de diez años de edad (SMD). El objetivo fue comparar la diversidad de ratones a través de este gradiente. Se implementaron dos cuadrantes de 5,000 m2/sitio, usando 50 trampas Sherman en una cuadrícula equidistante de 10 m durante dos noches consecutivas por mes en cada sitio. Se capturaron 478 ratones de seis especies con 1,754 recapturas. La SMD aportó el 38% de las capturas mientras que PA el 16%. Ototylomys phyllotis y Peromyscus yucatanicus aportaron el 47% y el 41%, respectivamente del total de las capturas. El sitio con la mayor riqueza específica y diversidad fue PA (H= 1.328), el sitio menos diverso fue SMD (H= 0.6321), pero con las máximas abundancias. Se presentaron diferencias significativas (P 0.05) entre sitios en cuanto a la diversidad excepto entre la SCA con SDA. Los valores de abundancia difieren fuertemente en todos los sitios. Las abundancias de O. phyllotis se vieron afectadas por el gradiente de perturbación debido a la influencia antropogénica y la topografía que están asociados a la diversidad observada.

In the 2013–2014 growing season, field surveys were conducted in native corn fields located in high altitude agricultural communities in the ‘Sierra Norte de Puebla’ in Mexico. Symptoms typical of maize bushy stunt (MBS) disease were observed and DNA extracted from symptomatic native corn plants was used as template to confirm the presence of phytoplasmas. Amplification and sequencing of 16S rRNA-encoding sequences and chaperonin 60 universal target (cpn60 UT) sequences followed by in vitro restriction fragment length polymorphism and phylogenetic analyses revealed that the phytoplasma detected belongs to the subgroup 16SrI-B, ‘Candidatus Phytoplasma asteris’. Based on 16S rRNA-encoding gene sequence analysis and on a single nucleotide polymorphism within the cpn60 UT sequence, two MBS strains, MBS-Puebla and MBS-Veracruz, were identified. This is the first detection of MBS phytoplasma (MBSP) affecting native corn and the first molecular survey made in corn fields in Mexico to detect and characterize MBSP. We discuss these results in light of the potential evolutionary relationship between corn and MBSP.

ResumenCon el fin de comparar la riqueza, diversidad y composición de especies de murciélagos, se capturaron murciélagos frugívoros utilizando redes de niebla en 4 bosques secundarios que representan un gradiente de alteración en el sureste de México. Se obtuvieron 691 murciélagos de 15 especies, de las cuales Artibeus jamaicensis (A. jamaicensis) y Sturnira lilium (S. lilium) fueron las más abundantes. No hubo diferencias significativas en la riqueza y diversidad de murciélagos frugívoros entre los bosques secundarios, aunque la composición de especies sí fue marcadamente diferente, siendo S. lilium, A. jamaicensis, Glossophaga soricina, Artibeus lituratus y Carollia sowelli las especies que más contribuyeron a estas diferencias. Los bosques secundarios, últimos refugios existentes en la llanura costera tabasqueña, una región dominada por pastizales y zonas urbanas, son importantes para la conservación de los murciélagos frugívoros y, en general, para la fauna silvestre.AbstractWe captured bats using mist nets in 4 secondary forests that represent a perturbation gradient in Southeast Mexico, in order to compare frugivore bat species richness, diversity and composition. We captured 691 frugivorous bats from 15 species; Artibeus jamaicensis (A. jamaicensis) and Sturnira lilium (S. lilium) were the most abundant. There were no significant differences in frugivorous bat richness and diversity in secondary forests, although species composition was notably different, S. lilium, A. jamaicensis, Glossophaga soricina, Artibeus lituratus and Carollia sowelli contributed the most to differences. Secondary forests are important for frugivorous bats conservation and in general for wildlife, since they are the last refuges in the Tabasco coastal plain, a region dominated by grasslands and urban areas.

Biodiversity continues to decline in the face of increasing anthropogenic pressures such as habitat destruction, exploitation, pollution and introduction of alien species. Existing global databases of species' threat status or population time series are dominated by charismatic species. The collation of datasets with broad taxonomic and biogeographic extents, and that support computation of a range of biodiversity indicators, is necessary to enable better understanding of historical declines and to project - and avert - future declines. We describe and assess a new database of more than 1.6 million samples from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. The database contains measurements taken in 208 (of 814) ecoregions, 13 (of 14) biomes, 25 (of 35) biodiversity hotspots and 16 (of 17) megadiverse countries. The database contains more than 1% of the total number of all species described, and more than 1% of the described species within many taxonomic groups - including flowering plants, gymnosperms, birds, mammals, reptiles, amphibians, beetles, lepidopterans and hymenopterans. The dataset, which is still being added to, is therefore already considerably larger and more representative than those used by previous quantitative models of biodiversity trends and responses. The database is being assembled as part of the PREDICTS project (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems - www.predicts.org.uk). We make site-level summary data available alongside this article. The full database will be publicly available in 2015. The collation of biodiversity datasets with broad taxonomic and biogeographic extents is necessary to understand historical declines and to project - and hopefully avert - future declines. We describe a newly collated database of more than 1.6 million biodiversity measurements from 78 countries representing over 28,000 species, collated from existing spatial comparisons of local-scale biodiversity exposed to different intensities and types of anthropogenic pressures, from terrestrial sites around the world. © 2014 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.