50 research outputs found
Arachis inflata: A New B Genome species of Arachis (Fabaceae)
Great efforts have been done to collect germplasm of the Arachis genus in South America, however, many regions still remain underexplored. Under the hypothesis that these regions have new and diverse populations/species of Arachis, several expeditions were carried out since 2000 in Bolivia, to increase the documentation of the genus diversity. As a first result of these explorations, a new species of section Arachis with B genome is formally described. Arachis inflata is closely related to A. magna and A. ipaënsis, but it can be clearly distinguished from them, and from any other species of the genus, for having a type of fruit with a completely distinct morphology. The fruit has a smooth epicarp, but shows a bullated aspect, due to the presence of air chambers in the mesocarp
Molecular confirmation of species status for the allopolyploid cotton species, Gossypium ekmanianum Wittmack.
Understanding the relationship between domesticated crop species and their wild relatives is paramount to germplasm maintenance and the utilization of wild relatives in breeding programs. Recently, Gossypium ekmanianum was resurrected as an independent species based on morphological analysis of specimens obtained from the Dominican Republic, where the original type specimen was collected. The molecular data presented here support the recognition of G. ekmanianum Wittmack as a distinct species that is phylogenetically close to G. hirsutum L. Analyses of chloroplast DNA data reveal species-specific, indel polymorphisms that unambiguously distinguish G. ekmanianum samples from other polyploid congeners. Furthermore, analysis of accessions that originated from the Dominican Republic demonstrate the cryptic inclusion of this sister taxon within the US National Plant Germplasm System, a germplasm collection maintained for diversity preservation and future breeding resources. The data presented here indicate that ‘‘wild’’ G. hirsutum accessions may include the closely related G. ekmanianum, and provide a method to easily distinguish the two.Fil: Grover, C. E.. University of Iowa; Estados UnidosFil: Zhu, X.. Nantong University; ChinaFil: Grupp, K. K.. University Of Iowa; Estados UnidosFil: Jareczek, J. J.. University of Iowa; Estados UnidosFil: J. P. Gallagher. University of Iowa; Estados UnidosFil: Szadkowski, E.. University of Iowa; Estados UnidosFil: Seijo, Jose Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Nordeste. Instituto de Botánica del Nordeste (i); Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura; ArgentinaFil: Wendel, J. F.. University of Iowa; Estados Unido
Variación del color de flores y números cromosómicos en el noroeste del área de distribución de Turnera sidoides (Turneraceae)
In the context of the evolutionary studies that are being carried out in Turners sidoides autopolyploid complex (x= 7), a systematic survey was made in the northwestern area (Bolivia) of its distribution. Six populations with salmon flowers and thirty five with yellow ones of the subsp. pinnatifida were found. The distribution of these populations is associated with climatic and spatial variables. The populations with salmon flowers live in the dry forests (Chaco Boreal Biogeographical Province), while yellow flowered populations occur in the inter-andean valleys (Boliviano-Tucumana Biogeographical Province). All the population studied are diploid. The results obtained support the allopatric diversification model of populations with yellow and salmon flowers at the diploid level, probably favoured by the orographic barriers and climatic changes that have arisen during the Andes development and Quaternary glaciations. Moreover, our analysis evidences that the north western area of T. sidoides constitutes an important centre of variation of the subsp. pinnatifida and the major centre of diploids hitherto detectedEn el marco de los estudios evolutivos que se desarrollan en el complejo autopoliploide Turnera sidoides (x= 7) se realizó un muestreo sistemático en el noroeste de su área de distribución. Se hallaron 6 poblaciones con flores de color salmón y 35 con flores amarillas de la subsp. pinnatifida. La distribución de estas poblaciones está asociada con variables climáticas y espaciales. Las poblaciones que presentan flores de color salmón viven en los bosques semiáridos (Provincia Biogeográfica del Chaco Boreal) y las de flores amarillas en los valles interandinos (Provincia Biogeográfica Boliviano-Tucumana). Todas las poblaciones analizadas son diploides. Los resultados obtenidos sustentan el modelo de diversificación alopátrica de las poblaciones con diferente color de flores a nivel diploide, probablemente favorecido por el sistema de barreras orográficas y los cambios climáticos surgidos a partir del levantamiento de los Andes y de las glaciaciones del Cuaternario. Además, el análisis evidencia que el noroeste del área de T. sidoides constituye un importante centro de variación de la subsp. pinnatifida y es el mayor centro de diploides hasta ahora detectad
Comparative repeatome analysis reveals new evidence on genome evolution in wild diploid Arachis (Fabaceae) species
The South American genus Arachis (Fabaceae) comprises 83 species organized in nine taxonomic sections. Among them,section Arachis is characterized by species with a wide genome and karyotype diversity. Such diversity is determined mainlyby the amount and composition of repetitive DNA. Here we performed computational analysis on low coverage genomesequencing to infer the dynamics of changes in major repeat families that led to the differentiation of genomes in diploidspecies (x = 10) of genus Arachis, focusing on section Arachis. Estimated repeat content ranged from 62.50 to 71.68% ofthe genomes. Species with different genome composition tended to have different landscapes of repeated sequences. Athilafamily retrotransposons were the most abundant and variable lineage among Arachis repeatomes, with peaks of transpositionalactivity inferred at different times in the evolution of the species. Satellite DNAs (satDNAs) were less abundant, butdifferentially represented among species. High rates of evolution of an AT-rich superfamily of satDNAs led to the differentialaccumulation of heterochromatin in Arachis genomes. The relationship between genome size variation and the repetitivecontent is complex. However, largest genomes presented a higher accumulation of LTR elements and lower contents ofsatDNAs. In contrast, species with lowest genome sizes tended to accumulate satDNAs in detriment of LTR elements. Phylogeneticanalysis based on repetitive DNA supported the genome arrangement of section Arachis. Altogether, our resultsprovide the most comprehensive picture on the repeatome dynamics that led to the genome differentiation of Arachis species.Fil: Samoluk, Sergio Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Vaio, Magdalena. Universidad de la Republica; UruguayFil: Ortiz, Alejandra Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Chalup, Laura María Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Robledo Dobladez, Germán Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Bertioli, David J.. University of Georgia; Estados UnidosFil: Seijo, José Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin
Introgression of peanut smut resistance from landraces to elite peanut cultivars (\u3ci\u3eArachis hypogaea\u3c/i\u3e L.)
Smut disease caused by the fungal pathogen Thecaphora frezii Carranza & Lindquist is threatening the peanut production in Argentina. Fungicides commonly used in the peanut crop have shown little or no effect controlling the disease, making it a priority to obtain peanut varieties resistant to smut. In this study, recombinant inbred lines (RILs) were developed from three crosses between three susceptible peanut elite cultivars (Arachis hypogaea L. subsp. hypogaea) and two resistant landraces (Arachis hypogaea L. subsp. fastigiata Waldron). Parents and RILs were evaluated under high inoculum pressure (12000 teliospores g-1 of soil) over three years. Disease resistance parameters showed a broad range of variation with incidence mean values ranging from 1.0 to 35.0% and disease severity index ranging from 0.01 to 0.30. Average heritability (h2) estimates of 0.61 to 0.73 indicated that resistance in the RILs was heritable, with several lines (4 to 7 from each cross) showing a high degree of resistance and stability over three years. Evidence of genetic transfer between genetically distinguishable germplasm (introgression in a broad sense) was further supported by simple-sequence repeats (SSRs) and Insertion/Deletion (InDel) marker genotyping. This is the first report of smut genetic resistance identified in peanut landraces and its introgression into elite peanut cultivars
Characterization of the Arachis (Leguminosae) D genome using fluorescence in situ hybridization (FISH) chromosome markers and total genome DNA hybridization
Genome re-assignment of Arachis trinitensis (Sect. Arachis, Leguminosae) and its implications for the genetic origin of cultivated peanut
FIDEL—a retrovirus-like retrotransposon and its distinct evolutionary histories in the A- and B-genome components of cultivated peanut
In this paper, we describe a Ty3-gypsy retrotransposon from allotetraploid peanut (Arachis hypogaea) and its putative diploid ancestors Arachis duranensis (A-genome) and Arachis ipaënsis (B-genome). The consensus sequence is 11,223 bp. The element, named FIDEL (Fairly long Inter-Dispersed Euchromatic LTR retrotransposon), is more frequent in the A- than in the B-genome, with copy numbers of about 3,000 (±950, A. duranensis), 820 (±480, A. ipaënsis), and 3,900 (±1,500, A. hypogaea) per haploid genome. Phylogenetic analysis of reverse transcriptase sequences showed distinct evolution of FIDEL in the ancestor species. Fluorescent in situ hybridization revealed disperse distribution in euchromatin and absence from centromeres, telomeric regions, and the nucleolar organizer region. Using paired sequences from bacterial artificial chromosomes, we showed that elements appear less likely to insert near conserved ancestral genes than near the fast evolving disease resistance gene homologs. Within the Ty3-gypsy elements, FIDEL is most closely related with the Athila/Calypso group of retrovirus-like retrotransposons. Putative transmembrane domains were identified, supporting the presence of a vestigial envelope gene. The results emphasize the importance of FIDEL in the evolution and divergence of different Arachis genomes and also may serve as an example of the role of retrotransposons in the evolution of legume genomes in general
Deep learning-based lesion subtyping and prediction of clinical outcomes in COVID-19 pneumonia using chest CT
The main objective of this work is to develop and evaluate an artificial intelligence system based on deep learning capable of automatically identifying, quantifying, and characterizing COVID-19 pneumonia patterns in order to assess disease severity and predict clinical outcomes, and to compare the prediction performance with respect to human reader severity assessment and whole lung radiomics. We propose a deep learning based scheme to automatically segment the different lesion subtypes in nonenhanced CT scans. The automatic lesion quantification was used to predict clinical outcomes. The proposed technique has been independently tested in a multicentric cohort of 103 patients, retrospectively collected between March and July of 2020. Segmentation of lesion subtypes was evaluated using both overlapping (Dice) and distance-based (Hausdorff and average surface) metrics, while the proposed system to predict clinically relevant outcomes was assessed using the area under the curve (AUC). Additionally, other metrics including sensitivity, specificity, positive predictive value and negative predictive value were estimated. 95% confidence intervals were properly calculated. The agreement between the automatic estimate of parenchymal damage (%) and the radiologists' severity scoring was strong, with a Spearman correlation coefficient (R) of 0.83. The automatic quantification of lesion subtypes was able to predict patient mortality, admission to the Intensive Care Units (ICU) and need for mechanical ventilation with an AUC of 0.87, 0.73 and 0.68 respectively. The proposed artificial intelligence system enabled a better prediction of those clinically relevant outcomes when compared to the radiologists' interpretation and to whole lung radiomics. In conclusion, deep learning lesion subtyping in COVID-19 pneumonia from noncontrast chest CT enables quantitative assessment of disease severity and better prediction of clinical outcomes with respect to whole lung radiomics or radiologists' severity score
Predictors of clinically significant quality of life impairment in Parkinson’s disease
COPPADIS Study Group.Quality of life (QOL) plays an important role in independent living in Parkinson’s disease (PD) patients, being crucial to know what factors impact QoL throughout the course of the disease. Here we identified predictors of QoL impairment in PD patients from a Spanish cohort. PD patients recruited from 35 centers of Spain from the COPPADIS cohort from January 2016, to November 2017, were followed up during 2 years. Health-related QoL (HRQoL) and global QoL (GQoL) were assessed with the 39-item Parkinson’s disease Questionnaire (PDQ-39) and the EUROHIS-QOL 8-item index (EUROHIS-QOL8), respectively, at baseline (V0) and at 24 months ± 1 month (V2). Clinically significant QoL impairment was defined as presenting an increase (PDQ-39SI) or decrement (EUROHIS-QOL8) at V2 ≥ 10% of the score at baseline (V0). A comparison with a control group was conducted for GQoL. GQoL did not change significantly in PD patients (N = 507; p = 0.686) or in the control group (N = 119; p = 0.192). The mean PDQ-39SI was significantly increased in PD patients (62.7 ± 8.5 years old; 58.8% males; N = 500) by 21.6% (from 16.7 ± 13 to 20.3 ± 16.4; p < 0.0001) at V2. Ninety-three patients (18.6%) presented a clinically significant HRQoL impairment at V2. To be younger (OR = 0.896; 95% CI 0.829–0.968; p = 0.006), to be a female (OR = 4.181; 95% CI 1.422–12.290; p = 0.009), and to have a greater increase in BDI-II (Beck Depression Inventory-II) (OR = 1.139; 95% CI 1.053–1.231; p = 0.001) and NMSS (Non-Motor Symptoms Scale) (OR = 1.052; 95% CI 1.027–1.113; p < 0.0001) total scores from V0 to V2 were associated with clinically significant HRQoL impairment at the 2-year follow-up (Hosmer–Lemeshow test, p = 0.665; R 2 = 0.655). An increase in ≥5 and ≥10 points of BDI-II and NMSS total score at V2 multiplied the probability of presenting clinically significant HRQoL impairment by 5 (OR = 5.453; 95% CI 1.663–17.876; p = 0.005) and 8 (OR = 8.217; 95% CI, 2.975–22.696; p = 0.002), respectively. In conclusion, age, gender, mood, and non-motor impairment were associated with clinically significant HRQoL impairment after the 2-year follow-up in PD patients.Mir P. has received honoraria from AbbVie, Abbott, Allergan, Bial, Merz, UCB and Zambon and have received grants from the Spanish Ministry of Economy and Competitiveness [PI16/01575] co-founded by ISCIII (Subdirección General de Evaluación y Fomento de la Investigación) and by Fondo Europeo de Desarrollo Regional (FEDER), the Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía [CVI-02526, CTS-7685], the Consejería de Salud y Bienestar Social de la Junta de Andalucía [PI-0437-2012, PI-0471-2013], the Sociedad Andaluza de Neurología, the Jacques and Gloria Gossweiler Foundation, the Fundación Alicia Koplowitz, the Fundación Mutua Madrileña.Peer reviewe