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

Plant genomes contain huge troves of information, and nowadays molecular tools to analyze genomes are less expensive and keep improving. In this review, we aimed to produce a “roadmap” to take advantage of this explosion of molecular methods and opportunities. We explain how to decide which strategies are adequate for a given evolutionary or taxonomic problem by describing 15 possible (and in some cases nonconsecutive) steps to take advantage of all the genomic resources drawing from the ever-increasing studies. We describe how to obtain an adequate genome sequence given our study species and objectives and discuss if we need to also obtain a transcriptome and additional “omic” data (i.e., proteome, metabolome, epigenome, microbiome). We analyze what is needed to conduct population genomics studies in terms of genomic methods and sampling strategies and discuss the pangenome concept. In addition, we present some considerations about how to estimate population genetics parameters and how to analyze geographic differentiation, inbreeding and gene flow. We examine ideas and methods on how to estimate natural selection and local adaptation, how to detect candidate genes, how coalescent analyses can help in these studies, the importance of genomic information for conservation studies and to understand adaptability to climate change. We assess the use of these methods in domestication studies and in understanding how form and function can be inferred from genes; likewise, how to use the genomic information for improvement of cultivated plants. We also review how can we use these methods in phylogenomic studies.

Paleobotany bears an invaluable source of knowledge for understanding the history of the biodiversity that we protect and care for today. This discipline is recognized as a source of information on physical, ecological, and biological events and processes that occurred in the past and are maintained today, but whose occurrences must be interpreted necessarily, and sometimes with limitations, solely from the lithosphere. The importance of studying past life from Mexico and addressing fossil plant reconstruction is highlighted to understand modern biodiversity. Fossils in Mexico have been studied marginally but contain valuable information to understand the history of biodiversity, both in Mexico and globally. We examined the extent to which Mexican fossils can contribute to understanding the origin and development of biological processes through time, and how past plant biodiversity in Mexico compares with the extant one. We used two sources to address these questions: (i) ideas on biological processes as seen through the fossil record, and (ii) fossils known from Mexico. Examples are given of how fossils, morphology, anatomy, and numerical methods, as well as genetics and physiology, illuminate each other to generate solid botanical concepts. The abundant and widely distributed outcrops with fossil plants suggest that further studies on Mexican material will be influential for varied biological hypotheses related to the origin and history of biodiversity. Mexican fossil plants and their scarce sampled localities are open to further investigation that will complement hypotheses on the historic discussion of biological processes.

Background: The genus Coryphantha has the second largest number of species of the tribe Cacteae-Cactaceae. Morphologically, it has been reported that the stem presents mainly globose, ovoid and cylindric variations. However, at the anatomical level, descriptions are scarce and focused on particular tissues (epidermis or xylem). The aim of this work is to contribute to the anatomical knowledge of the genus. Questions and/or Hypotheses: What are the anatomical characteristics that differentiate one species from another? Does the presence of crystals allow differentiation between species? Study species: Coryphantha clavata, Coryphantha cornifera and Coryphantha radians. Site and years of study: San Luis Potosí and Querétaro, Mexico; 2017, 2020. Methods: Three individuals per species were collected, and conventional histological techniques were applied. Anatomical descriptions were made for different tissues, and structural characteristics were measured for each species. Results: The species exhibited the greatest differences in the epidermis and hypodermis, such as the presence of subepidermal stomata (C. radians), three-layered hypodermis (C. clavata), and non-collenchymatous hypodermis (C. cornifera). Crystals were not observed in the epidermises but instead in the hypodermes, which exhibited crystal shapes of druses (C. cornifera and C. radians), prisms and round bodies (C. clavata). In the cortical tissue, C. clavata had abundant mucilage cells. The observed xylem and phloem tissues exhibited characteristics similar to those of other Coryphantha species. Conclusions: The anatomical characteristics of the epidermis and hypodermis are considered of high systematic value and could be used to distinguish between species of the genus.

Background: There is no previous evidence in the literature that documents the presence of extrafloral nectaries (EFNs) or the exomorphology of domatia in Nephelium lappaceum (rambutan), a fruit tree native to Malaysia introduced in various American countries. Question: It is the presence of EFNs responsible for the frequent visit of ants to young leaves of Nephelium lappaceum? Study site and dates: This study was conducted in a commercial rambutan orchard in the town of Francisco I. Madero, municipality of Frontera Hidalgo (Chiapas, Mexico) during the period September 2020-February 2021. Methods: External morphology of EFNs and domatia were studied using scanning electron microscopy. Nectar sugar concentration produced by EFNs was determined by refractometry. EFNs location on the plant and the frequency of visiting ants were quantified by visual counting. Results: A description of the external morphology of EFNs and domatia, as well as their location on rambutan leaflets are presented. A volume of 0.3 ± 0.2 µL/EFN of a nectar (9.3 ± 0.6 °Bx) was collected each day. Ten species of ants feeding on the nectar excreted by the EFNs were identified. Conclusion: Evidence of the presence of NEFs on rambutan leaflets is presented, which have an external morphology and location different from that observed in domatia, producing a sweet nectar used as food by a large community of ants.

Structured projection models (SPMs) are a powerful tool to investigate the dynamics of structured populations, which makes them ideal for the study of plant species spanning their range of life forms, sizes, longevity, and life cycle complexity. They are one of the most versatile tools in plant ecology, with hundreds of species studied so far and a wide variety of alternative formulations for different questions and purposes. We revise some of the most salient conceptual and methodological issues in the construction and use of SPMs including both discrete matrix projection models and continuous integral projection models. Consideration is given to the selection of the state variable and the estimation of parameters, especially those involving transitions difficult to observe in the field, such as the quantification of offspring production and the rarely observed mortality of individuals towards the end of the life cycle. Due to the growing importance of investigating population trends in a rapidly changing world, we highlight the use of SPMs for populations under a variety of environmental influences and/or away from their expected equilibrium. The presumed role of population density receives special attention because it often correlates with features of the environment, thus potentially confounding the two effects. Similarly, disentangling the various environmental effects poses challenges of its own, making it difficult to prove causality. The alternatives available are illustrated considering the selection of variables, samples, and model type suitable for specific purposes.

In Mexico, plants with crassulacean acid metabolism (CAM) are part of the Mexican culture, have different uses and are even emblematic. Unfortunately, only a small fraction of the Mexican CAM plants has been studied physiologically. For this review, the following questions were considered: What ecophysiological studies have been conducted with CAM species native to Mexico? What ecophysiological processes in Mexican CAM plants are the most studied? What type of ecophysiological studies with CAM plants are still needed? A database of scientific studies on CAM plant species from Mexico was documented, including field and laboratory works for species widely distributed, and those studies made outside Mexico with Mexican species. Physiological processes were grouped as germination, photosynthesis, and water relations. Most studies were done for CAM species of Cactaceae, Bromeliaceae, Asparagaceae and Orchidaceae, andmost ecophysiological studies have been done on germination of cacti. Field and laboratory studies on photosynthesis and water relations were mostly for terrestrial cacti and epiphytic bromeliads. There were few physiological studies with CAM seedlings in Mexico and few studies using stable isotopes of water and carbon of CAM plants in the field. More field and laboratory studies of physiological responses and plasticity of CAM plants to multiple stress factors are required to model plant responses to global climate change. In general, more physiological studies are essential for all CAM species and for species of the genus Clusia, with C3-CAM and CAM members, which can become ecologically important under some climate change scenarios.

Background: Limited number of studies have been conducted to determine the ethnobotanical uses of geophytes and to scientifically document traditional knowledge associated with them. Questions: What is the ethnobotanical usage culture of geophytes in Sakarya province? Studied species: Geophytes. Study site and dates: Sakarya, Turkey; 2017 to 2020. Methods: Information in the local community was obtained through face to face or collective interviews. In addition, cultural importance index (CII) and the informant consensus factor (ICF) values were calculated. Results: In this study, the knowledge of the local public about 115 geophytes (107 natural and eight cultivated) belonging to 26 families was revealed. The most common families are Asparagaceae (23 taxa), Iridaceae (20 taxa) and Amaryllidaceae (14 taxa). The most common genera are Crocus (12 taxa), Orchis (7 taxa) and Allium (6 taxa). Out of a total of 115 taxa, 226 uses are reported, including 128 folk remedies, 47 ornamental plants, 48 food and three the other uses. The most widely used plant according to cultural importance index is Leucojum aestivum (Gölsoğanı,  CII: 2.57). Conclusion: Our interviews revealed that the geophytes in the study area are still widely used by people in their daily lives for medicinal, food and floricultural purposes. In addition, the ethnobotanical uses of Crocus speciosus subsp. sakariensis, Crocus keltepensis, Fritillaria bithynica and Muscari pamiryigidii are reported for the first time in Turkey.

Background: Pollen, as all other plant tissues, harbors different microorganisms. As honey bees (Apis mellifera) collect and pack pollen they add regurgitated nectar to moisten and glue the pollen grains, possibly changing the microbial composition. Hypothesis: We hypothesize that while packing pollen into their corbiculae, honey bees change the pollen microbiota. Studied species: Brassica napus L., Apis mellifera L. Study site and dates: Avignon, France, 2018. Methods: In this study, we compared the microbiota of clean Brassica napus (Brassicaceae) pollen with that of bee-worked corbicular pollen by 16S rRNA gene targeted amplicon sequencing. We also compared these bacterial communities with those present in nectar, the bee gut and the bee surface as potential inoculum sources. Results: We found that by working pollen, bees increase the bacterial diversity of pollen, by adding honey bee symbionts such as Bombella, Frischella, Gilliamella and Snodgrassella, bee pathogens as Spiroplasma and nectar dwelling Lactobacillus to the new pollen microbiota. Conclusions: The bee gut is an important source of inoculum of the corbicular pollen microbiota. We discuss the implications of these findings and propose future research avenues.

Elementos Blog Botanical Sciences

Elementos Blog Botanical Sciences