Interrelación entre la densidad de tallos y la tasa de multiplicación de tubérculos en papa criolla (solanum phureja juz. et buk) variedad "yema de huevo"

Se evaluó el efecto de diferentes densidades de siembra sobre la densidad de tallos (número de tallos/m2) y la tasa de multiplicación (número de tubérculos producidos a partir de un tubérculo-sernilla) en papa criolla (Solanum phureja Juz. et Buk.) variedad "yema de huevo", utilizando cuatro distancias entre surcos (0,70; 0,80; 0,90 y 1,0 m.) y tres distancias entre plantas (0,20; 0,25 y 0,30 m.), también, se cuantificó el número de ojos sembrados y se estableció la correlación entre estas variables. Los resultados mostraron que la densidad de tallos se incrementó significativamente cuando se disminuyó la distancia entre plantas y la distancia entre surcos, pero no se correlacionó significativamente con la tasa de multiplicación. Cuando se utilizaron distancias entre plantas menores de 0,30 m la tasa de multiplicación fue mayor, y no se vio afectada por la distancia entre surcos. EI número de ojos sembrados/m2 se correlaciono directamente con la densidad de tallos y, en forma inversa, con la tasa de multiplicación.The effect of different planting densities on stem density and multiplication rate was evaluated in the diploid potato variety ''yema de huevo" employing four different row distances (0,70; O,BO; 0,90 and 1,0 m) and three distances between hills (0,20; 0,25 and 0,30 m). The number of eyes per tuber was also measured as well as the possible correlation of all these variables. The results indicated that stem density increased when distances between rows and between hills were shorter and were not correlated statistically with multiplication rate. The multiplication rate increased at distances between hills were below 0,30 m and was not affected by row distances. Stem density was directly related to the number of eyes in the tubers, and the multiplication rate was inversely affected by the eyes in the tubers

Genomic lineages of Rhizobium etli revealed by the extent of nucleotide polymorphisms and low recombination

<p>Abstract</p> <p>Background</p> <p>Most of the DNA variations found in bacterial species are in the form of single nucleotide polymorphisms (SNPs), but there is some debate regarding how much of this variation comes from mutation versus recombination. The nitrogen-fixing symbiotic bacteria <it>Rhizobium etli </it>is highly variable in both genomic structure and gene content. However, no previous report has provided a detailed genomic analysis of this variation at nucleotide level or the role of recombination in generating diversity in this bacterium. Here, we compared draft genomic sequences versus complete genomic sequences to obtain reliable measures of genetic diversity and then estimated the role of recombination in the generation of genomic diversity among <it>Rhizobium etli</it>.</p> <p>Results</p> <p>We identified high levels of DNA polymorphism in <it>R. etli</it>, and found that there was an average divergence of 4% to 6% among the tested strain pairs. DNA recombination events were estimated to affect 3% to 10% of the genomic sample analyzed. In most instances, the nucleotide diversity (π) was greater in DNA segments with recombinant events than in non-recombinant segments. However, this degree of recombination was not sufficiently large to disrupt the congruence of the phylogenetic trees, and further evaluation of recombination in strains quartets indicated that the recombination levels in this species are proportionally low.</p> <p>Conclusion</p> <p>Our data suggest that <it>R. etli </it>is a species composed of separated lineages with low homologous recombination among the strains. Horizontal gene transfer, particularly via the symbiotic plasmid characteristic of this species, seems to play an important role in diversity but the lineages maintain their evolutionary cohesiveness.</p

Empoderamiento y feminismo comunitario en la conservación del maíz en México

Articulo científico para revista indizada.El objetivo es analizar, desde una perspectiva basada en el feminismo comunitario, el proceso de empoderamiento de las mujeres que conforman un grupo de ocho integrantes matlatzincas de la comunidad de San Francisco Oxtotilpan, México, a través de prácticas productivas, alimentarias y culturales en torno al maíz nativo. Los datos fueron recogidos durante 2014 y 2015 con técnicas etnográficas que incluyen: observación participante, historias de vida, grupos focales, entrevistas semiestructuradas y a profundidad. Son mujeres que muestran cinco dimensiones de poder (social, corporal, material, simbólico y cognitivo) que repercuten en la preservación del maíz nativo, al generar la masa crítica necesaria para incorporar a otras mujeres en acciones favorables para la soberanía alimentaria

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

Interrelación entre la densidad de tallos y la tasa de multiplicación de tubérculos en papa criolla (solanum phureja juz. et buk) variedad "yema de huevo" Interrelationship among the stem density and the multiplication rate in the diploid potato variety "yema de huevo" (Solanum phureja Juz. et Buk)

Se evaluó el efecto de diferentes densidades de siembra sobre la densidad de tallos (número de tallos/m2) y la tasa de multiplicación (número de tubérculos producidos a partir de un tubérculo-sernilla) en papa criolla (Solanum phureja Juz. et Buk.) variedad "yema de huevo", utilizando cuatro distancias entre surcos (0,70; 0,80; 0,90 y 1,0 m.) y tres distancias entre plantas (0,20; 0,25 y 0,30 m.), también, se cuantificó el número de ojos sembrados y se estableció la correlación entre estas variables. Los resultados mostraron que la densidad de tallos se incrementó significativamente cuando se disminuyó la distancia entre plantas y la distancia entre surcos, pero no se correlacionó significativamente con la tasa de multiplicación. Cuando se utilizaron distancias entre plantas menores de 0,30 m la tasa de multiplicación fue mayor, y no se vio afectada por la distancia entre surcos. EI número de ojos sembrados/m2 se correlaciono directamente con la densidad de tallos y, en forma inversa, con la tasa de multiplicación.The effect of different planting densities on stem density and multiplication rate was evaluated in the diploid potato variety ''yema de huevo" employing four different row distances (0,70; O,BO; 0,90 and 1,0 m) and three distances between hills (0,20; 0,25 and 0,30 m). The number of eyes per tuber was also measured as well as the possible correlation of all these variables. The results indicated that stem density increased when distances between rows and between hills were shorter and were not correlated statistically with multiplication rate. The multiplication rate increased at distances between hills were below 0,30 m and was not affected by row distances. Stem density was directly related to the number of eyes in the tubers, and the multiplication rate was inversely affected by the eyes in the tubers