Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Background: Tagetes contains about 55 species, its largest center of diversification is in Mexico with 35. Nearly 10 % of the species have cultural and economic importance. To date, anatomical studies are lacking in most of its species. Question: Are there foliar anatomical characters with diagnostic value that allow discriminating between the nine species of Tagetes studied? Study species: T. lacera, T. lemmonii, T. linifolia, T. lucida, T. lunulata, T. micrantha, T. parryi, T. stenophylla, T. zypaquirensis. Study site and date: Natural distribution areas in the Mexican Highlands, Trans-Mexican Volcanic Belt and the Genetics Experimental Field, Chapingo Autonomous University, Texcoco, State of Mexico, during 2017. Methods: Botanical specimens were collected. Leaves were fixed and subjected to conventional anatomical techniques, as clearing and embedding in paraffin for their observation and analysis. Results: Tagetes species develop entire and pinnatisect leaves, secondary venation pattern was eucamptodromous becoming reticulodromous distally and simple and festooned brochidodromous. The marginal ultimate venation was incomplete except for T. lunulata. Abundant and diverse trichomes, dorsiventral and isolateral mesophyll, collateral vascular bundles with sheath, and ducts in mesophyll and midvein were observed. Conclusions: The leaf architecture and anatomy of the studied species reveals common characters in Asteraceae. However, in Tagetes the type of trichomes, of mesophyll, size of ducts, and sclerenchyma associated to vascular bundles are important. Translate stop  

Background: Dry Forest can be recovered with restoration plantings. Selection of tree species for restoration plantings depends on its successful performance under the adverse conditions of degraded areas. Hypotheses: Early-successional legume species have higher survival in degraded areas. Studied species: Twelve native tree species from the dry forest. Study site and dates: Pastures excluded from cattle ranching activities in Quilamula, Tlaquiltenango, Morelos, Mexico for 28 months, from July 2017 to October 2019. Methods: Experimental plantings of 12 tree species (N= 1,080 juveniles). Survival was registered in October 2017, June and October 2018, and in October 2019. Results: Early-successional tree species showed higher survival (27 %) than late- successional species (20 %). Legumes showed higher survival (25 %) tan non-legumes (22 %). Early non-legume species and late-successional legumes had a similar and higher survival (> 30 %) than early-successional legume species (<18 %). Conclusions: To ensure the success of restoration plantings and accelerate the recovery of the forest, it is suggested to plant a mix of early-successional species (i.e., Dodonaea viscosa Jacq. and Leucaena leucocephala (Lam.) De Wit) and as many late-successional legumes and non-legumes species as possible.

Background: The geographic distribution of Pinguicula moranensis var. neovolcanica is restricted to the Trans-Mexican Neovolcanic Belt. In Tlaxcala, this species has disappeared in most of the sites where it had been registered. Understand relationships among environmental, morphological, and reproductive characteristics in the prevailing population is needed. Questions and / or Hypotheses: What is the effect of the environment and morphological characteristics on biotic and reproductive variables of P. moranensis in Tlaxcala? Studied species: Pinguicula moranensis var. neovolcanica Zamudio. Study site and date: Panotla and San José Teacalco, Tlaxcala, México. February and July in 2019. Methods: In two sites where abiotic variables (light and humidity) as well as biotic variables (density, prey, and floral visitors) were recorded. The plant´s morphological characteristics (rosette diameter, length, and number of peduncles and flowers) and reproductive characteristics (total numbers of seeds, fertile or aborted seeds, and viability) were recorded. Results: Positive effects on prey abundance were found for the abiotic variable humidity, as well as for the morphological characteristics of number of peduncles and number of fertile seeds. The taxonomic diversity of prey was related to the number of fertile seeds. Similarly, light, individual density, and seed viability had a positive effect on the number of fertile seeds. Conclusions: The present results indicate that abiotic, biotic, morphological, and reproductive variables interact to determine the persistence of the P. moranensis population in Tlaxcala. Moreover, this study emphasize the importance of habitat conservation in the Trans-Mexican Volcanic Belt. Translate stop   Translate stop   Translate stop   Translate stop   Translate stop  

Background: Cocoa is a species commonly cultivated under agroforestry systems (AFs), when microclimate conditions are adequate, it achieves high growth rates and seed yield. Questions and Hypotheses: How do four cocoa varieties respond to open (OC) and closed (CC) shade tree canopy conditions within AFs? We hypothesized that cocoa functional traits values correlate with microclimate conditions in the CC. Studied species: Theobroma cacao L. (Malvaceae). Study site and dates: Papantla, Nautla, Veracruz; San Pedro, Oaxaca. Rainy season, 2018. Methods: Three AFs were selected; either one with OC and CC zones, photosynthetically active radiation (PAR), vapor pressure deficit (VPD), air temperature (Ta) and relative humidity (RH) were registered. Cocoa tree and leaves functional traits were evaluated in four regional cocoa varieties, in ten individuals per variety, canopy condition and AFs. Results: Higher values of PAR, VPD and Ta, and lower RH were recorded under OC than in CC. Cocoa tree height, stem diameter, fruit production, SLA (Specific Leaf Area), LWC (Leaf Water Content) and SS (Stomatal Size) were higher for Nautla. Only the cocoa clone Inifap8 displayed higher height and fruit production than the other varieties. Conclusions: Veracruz and Oaxaca states have AFs with microclimatic conditions where cocoa cultivation can potentially develop. However, it is essential to incorporate our understanding of the adaptive responses of cocoa to particular shade trees canopy structure. Cocoa leaf traits, SLA, LWC and SS, may be used as indicators for enhancing management and sustainability in AFs in the face of climate change. Translate stop   Translate stop  

Background: Forests of Pinus pinceana in the Eastern Sierra Madre of Tamaulipas grow in dry environmental conditions. It is important to know the composition and floristic diversity, as well as the useful structural parameters for future conservation programs. Questions: What is the structure, composition and floristic diversity of the vegetation associated with the Pinus pinceanaforest in Tamaulipas? Studied species / data description /Mathematical model: Pinus pinceana, structural parameters, diversity, and linear regression models. Study site and dates: State of Tamaulipas, Mexico. March 2016 to March 2017. Methods: At each site (A and B) three strata were analyzed, ten 100 m2 plots for high stratum, 25 m2 for medium stratum and 1 m2 for low stratum, for a total of 30 plots per site. Results: A total of 48 species, 39 genera and 24 families of vascular plants were recorded. Fabaceae, Euphorbiaceae and Asparagaceae were the most representative families. Pinus pinceana had the highest Importance value index (IVI), whereas Flourensia laurifolia and Acacia roemeriana had the highest IVI values for the medium stratum. For the low stratum Croton ciliatoglandulifer and Hechtia hernandez-sandovalii had the highest IVI value. Significant differences were also found in the structure of the middle and upper stratum between the two study sites. Translate stop   Translate stop   Translate stop  

Background: Potential distribution models are widely used to estimate and predict changes in the distribution of a species in response to different processes of global change. Knowing the extent and distribution of vegetation is a basic step for measuring the environmental status of a basin. Questions: What are the bioclimatic variables that most contribute to the distribution of riparian trees in a basin? What is the environmental similarity among distributed species in a basin? Studied species: 17 species of riparian trees. Study site and dates: Bajo Río Grijalva sub basin, January – December 2020. Methods: Potential distribution models were obtained for 17 riparian tree species using 19 climate variables and three topographic variables using the Maximum Entropy method. The evaluation of the models was done with the results of the analysis of the area under the curve (AUC). Results: The models presented an AUC value > 0.8 for most species. The results obtained showed maps of potential distribution of the 17 species, 11 of them distributed in the part of the study area with highest altitude, 13 in the middle part, and all match in the part with the lowest altitude. Upon analyzing the bioclimatic profile of the modeled species, it was observed that the slope, aspect and elevation were the variables that determined in greater proportion the potential distribution of species. Conclusions: When analyzing the similarity of the species with respect to environmental variables, Haematoxylum campechianum stands out as the species with the greatest environmental difference. Translate stop   Translate stop   Translate stop  

Background: Agastache foeniculum is one of the perennial aromatic plants of the Lamiaceae family. The essential oil (EO) of this plant has potent antibacterial and antifungal properties, and hence it is extensively used in the pharmaceutical and food industries. Water-deficit stress occurring at any plant growth stage changes the morphological, phytochemical, and physiological processes. Melatonin is considered as a new kind of plant growth regulator which increases plant tolerance to environmental stresses. Hypotheses: The response to water deficit in A. foeniculum is Mel-dependent and affects their physiological and phytochemical characteristics Studied species: Agastache foeniculum Study site and dates: Tabriz, Iran, 2019. Methods: For this purpose, plants were subjected to water-deficit stress, which was followed by foliar application of melatonin as biostimulants on dry matter and secondary metabolites of A. foeniculum. Results: Results indicated that water-deficit stress (at 60 % of Field capacity) increased shoot dry weight, total phenol, anthocyanins and flavonoids content as well as EO content. Application of various melatonin concentrations improved the content of the mentioned traits. According to GC-MS analysis, ten chemical compounds were recognized in the EO composition of A. foeniculum. The most important EO compound (%) in the studied treatments was methyl chavicol, under severe water-deficit stress conditions with Mel at  concentration of 100 μM. Conclusions: The results indicated that the application of Mel (at 100 µM) as a bio-inducer can alleviate the detrimental effects of water-deficit stress (at 60 and 30 % field capacity) and improve the quality of EO.

Background: San Miguel Tolimán, in the municipality of Tolimán, Querétaro, is part of the Sierra Gorda-Río Moctezuma priority region for conservation. In the area along the Tolimán River there is gallery forest vegetation (BG) adjacent to xerophytic scrub (MX); the site lacks an inventory of its flora. Questions: What is the angiosperm richness of the MX and BG? What is the percentage of native, endemic, and at-risk species in both communities? Study species and data description: List of angiosperms in the area. Study site and date: MX and BG of San Miguel Tolimán, municipality of Tolimán, Querétaro, Mexico; November 2017 to September 2018. Methods: Bimonthly sampling of angiosperms during one year in 25 ha/community. Results: Two vegetation types were recognized: MX and disturbed gallery forest (BGP). 131 species were recorded: 54 in the MX (19 endemic and 16 at risk) and 79 in the BGP (12 exotic; 8 endemic and 9 at risk), with two species shared among the communities. In the MX, the families Asteraceae and Cactaceae were the most diverse and in the BGP Asteraceae followed by Poaceae and Malvaceae. In both communities herbaceous followed by shrubs were the biological forms with the highest number of species. Conclusions:  This study shows the great diversity of species present in a relatively small area and constitutes a precedent for prioritizing the conservation of plant resources in this zone.

Background: Hot-cold conception is important for plant-disease relationships in peasant communities, where introduced species acquire medicinal uses and are more available in anthropocentric systems than native; how these are selected is studied with indices, hypotheses that contribute to theories are rarely tested. Hypotheses: There will be more medicinal introduced species that will have more versatility than native ones; home-gardens will have more availability of them than the forest. Study site and dates: San Pedro Topiltepec (SPT), San Andrés Nuxiño (SAN), Oaxaca, September 2015-March 2017. Methods: Medicinal flora and its uses were inventoried by community, recording availability (socioecological system) and status (native/introduced) by species. Informant consensus factor and relative value estimated information similarity among informants; use value (UV) indicated species versatility. Hot-cold conditions were recorded by species and disease. Results: Species and diseases were 64 (75 % native, 25 % introduced) and 134 in SAN, 81 (52 % native, 48 % introduced) and 177 in SPT, respectively. In SAN 58 % species were available in forests, in SPT 62 % species were available in home gardens. UV was higher for native plants in SAN and for introduced plants in SPT. Hot-cold dichotomy influenced selection of medicinal plants in both communities. Conclusions: Both communities belong the same ethnicity, select medicinal plants differently. SAN uses a higher proportion of native plants, forests have higher species availability, native plants are the most versatile. SPT uses similar proportions of native and introduced plants, home gardens have more availability, introduced plants are the most versatile.

Background: Lianas are an important woody component of tropical rain forests. We described and compared the composition, structure, and diversity of the liana community in one of the northernmost neotropical rain forests. Question: How much does this liana community differ in attributes with global patterns documented in other tropical and subtropical rain forests? Study site and dates: Los Tuxtlas Tropical Biology Station, Veracruz, Mexico. 2015-2018. Methods: We censused all lianas ≥ 1 cm in diameter in a 1-ha plot and determined dominant families and species, diametric distribution, and diversity of order q. Results: We recorded 396 liana stems, 42 species, and 20 families. Basal area was 6619.2 cm2. Order 1 and 2 diversity was 21.9 and 13.4, respectively. Apocynaceae, Bignoniaceae, Celastraceae, and Malpighiaceae accounted for about 60 % of abundance and basal area, and 45.2 % of species richness. The 10 most abundant species included more than 60 % of stems and basal area. Conclusions: Species richness, abundance, and basal area were low compared with other tropical and subtropical sites worldwide. It was noteworthy the coincidence of some dominant species and families across the Neotropics and the absence of Fabaceae among the most important families. Latitudinal location and some key climatic factors such annual average rainfall and dry season length may explain, in part, our findings.