Population Genomics Provide Insights into the Global Genetic Structure of Colletotrichum graminicola, the Causal Agent of Maize Anthracnose.

Understanding the genetic diversity and mechanisms underlying genetic variation in pathogen populations is crucial to the development of effective control strategies. We investigated the genetic diversity and reproductive biology of Colletotrichum graminicola isolates which infect maize by sequencing the genomes of 108 isolates collected from 14 countries using restriction site-associated DNA sequencing (RAD-seq) and whole-genome sequencing (WGS). Clustering analyses based on single-nucleotide polymorphisms revealed three genetic groups delimited by continental origin, compatible with short-dispersal of the pathogen and geographic subdivision. Intra- and intercontinental migration was observed between Europe and South America, likely associated with the movement of contaminated germplasm. Low clonality, evidence of genetic recombination, and high phenotypic diversity were detected. We show evidence that, although it is rare (possibly due to losses of sexual reproduction- and meiosis-associated genes) C. graminicola can undergo sexual recombination. Our results support the hypotheses that intra- and intercontinental pathogen migration and genetic recombination have great impacts on the C. graminicola population structure. IMPORTANCE Plant pathogens cause significant reductions in yield and crop quality and cause enormous economic losses worldwide. Reducing these losses provides an obvious strategy to increase food production without further degrading natural ecosystems; however, this requires knowledge of the biology and evolution of the pathogens in agroecosystems. We employed a population genomics approach to investigate the genetic diversity and reproductive biology of the maize anthracnose pathogen (Colletotrichum graminicola) in 14 countries. We found that the populations are correlated with their geographical origin and that migration between countries is ongoing, possibly caused by the movement of infected plant material. This result has direct implications for disease management because migration can cause the movement of more virulent and/or fungicide-resistant genotypes. We conclude that genetic recombination is frequent (in contrast to the traditional view of C. graminicola being mainly asexual), which strongly impacts control measures and breeding programs aimed at controlling this disease.

Inactivation of the lipoxygenase ZmLOX3 increases susceptibility of maize to Aspergillus spp.

Plant and fungal lipoxygenases (LOX) catalyze the oxidation of polyunsaturated fatty acids, creating fatty-acid hydroperoxides (oxylipins). Fungal oxylipins are required for normal fungal development and secondary metabolism, and plant host-derived oxylipins interfere with these processes in fungi, presumably by signal mimicry. The maize LOX gene ZmLOX3 has been implicated previously in seed-Aspergillus interactions, so we tested the interactions of a mutant maize line (lox3-4, in which ZmLOX3 is disrupted) with the mycotoxigenic seed-infecting fungi Aspergillus flavus and Aspergillus nidulans. The lox3-4 mutant was more susceptible than wild-type maize to both Aspergillus species. All strains of A. flavus and A. nidulans produced more conidia and aflatoxin (or the precursor sterigmatocystin) on lox3-4 kernels than on wild-type kernels, in vitro and under field conditions. Although oxylipins did not differ detectably between A. flavus-infected kernels of the lox3-4 and wild-type (WT) maize, oxylipin precursors (free fatty acids) and a downstream metabolite (jasmonic acid) accumulated to greater levels in lox3-4 than in WT kernels. The increased resistance of the lox3-4 mutant to other fungal pathogens (Fusarium, Colletotrichum, Cochliobolus, and Exserohilum spp.) is in sharp contrast to results described herein for Aspergillus spp., suggesting that outcomes of LOX-governed host-pathogen interactions are pathogen-specific.

Relationships among resistances to fusarium and Aspergillus ear rots and contamination by fumonisin and aflatoxin in maize.

ABSTRACT Fusarium verticillioides, F. proliferatum, and Aspergillus flavus cause ear rots of maize and contaminate the grain with mycotoxins (fumonisin or aflatoxin). The objective of this study was to investigate the relationships between resistance to Fusarium and Aspergillus ear rots and fumonisin and aflatoxin contamination. Based on a previous study of 143 recombinant inbred lines from the cross NC300 x B104, 24 lines with the highest and 24 lines with the lowest mean fumonisin concentration were selected for further evaluation. Paired plots of each line were inoculated with F. verticillioides and F. proliferatum or with A. flavus in replicated trials in 2004 and 2005 in Clayton, NC, and College Station, TX. The low-fumonisin group had significantly lower levels of fumonisin, aflatoxin, and Fusarium and Aspergillus ear rots. Across year-location environments, all four traits were significantly correlated; the genotypic correlation (r(G)) ranged from r(G) = 0.88 (aflatoxin and Aspergillus ear rot) to r(G) = 0.99 (Fusarium and Aspergillus ear rots). Quantitative trait loci (QTLs) were identified and their effects estimated. Two QTLs affected both toxin concentrations, one QTL affected both ear rots, and one QTL affected Aspergillus and Fusarium rots and fumonisin. These results suggest that at least some of the genes involved in resistance to ear rots and mycotoxin contamination are identical or genetically linked.

A Copa do Mundo de futebol 2014 na região sul do Brasil: uma análise dos espaços da cidade / La Copa Mundial de Fútbol 2014 en la región sur de Brasil: un análisis de los espacios de la ciudad / The 2014 Football World Cup in southern brazil: an analysis of city spaces

O objetivo desta pesquisa foi identificar as transformações das cidades do sul do Brasil que foram sede da Copa do Mundo de Futebol 2014, principalmente no que se refere aos espaços de lazer e esporte. Trata-se de uma pesquisa descritiva de abordagem qualitativa. Os espaços delimitados foram os espaços e equipamentos do entorno dos estádios Joaquim Américo, em Curitiba/PR, e Beira-Rio, em Porto Alegre/ RS. Participaram da entrevista 25 sujeitos da cidade de Curitiba e 30 de Porto Alegre. Os resultados indicam que as mudanças se restringem aos estádios que são privados e algumas melhorias dos espaços que estão próximos aos espaços.

The aim of this research was to identify changes in southern Brazilian cities that hosted the 2014 Football World Cup, especially with regard to leisure and sporting spaces. It is a descriptive qualitative study. Spaces and equipment chosen were located near the Joaquim Américo stadium in Curitiba, PR, and the Beira-Rio stadium in Porto Alegre, RS. Twenty-five subjects from the city of Curitiba and 30 from Porto Alegre were interviewed. The results indicate that changes were restricted to private stadiums and to some improvements in areas that are near the spaces.

El objetivo de esta investigación fue identificar las transformaciones de las ciudades del sur de Brasil que fueron sede de la Copa Mundial de Fútbol de 2014, especialmente en lo que se refiere a los espacios de ocio y deporte. Es una descriptiva con un abordaje cualitativo. Los espacios delimitados fueron los locales y equipos que se encuentran en los alrededores de los estadios Joaquim Américo, en Curitiba, Paraná y Beira-Rio, en Porto Alegre, Rio Grande do Sul. Participaron en la entrevista 25 individuos de la ciudad de Curitiba y 30 de Porto Alegre. Los resultados indican que los cambios se limitan a los estadios, que son privados, y algunas mejoras en las áreas que están cerca de esos espacios.

Parques urbanos de Barcelona: relação entre usos principais e combinados, a diversidade nas formas de apropriação e a segurança / Barcelona's urban parks: the relationship between different forms of appropriation and safety from major and co-related uses

A intenção foi analisar o modelo de parques, praças e ruas de Barcelona com ênfase na relação entre diferentes formas de apropriação e a segurança desses espaços com base no conceito de usos principais e combinados de Jacobs (2000). Os procedimentos metodológicos foram: aplicação de protocolo desenvolvido no GEPLEC/UFPR, imagens fotográficas, filmagens e entrevistas semi-estruturadas com gestores e usuários. Concluiu-se que, em Barcelona, alguns espaços públicos contemplam tais formas de uso correlacionado, que dependem de uma série de fatores. Dentre esses, o planejamento urbano, que deve conectar espaços para garantir diversidade de experiências, a segurança, e, portanto, a vida pública nas grandes cidades.

The intention this paper was to analyze the model of Barcelona´s parks, plazas and streets, emphasising the relationship among different forms of appropriation and safety of these spaces, based on the concepts of major and co-related uses from JACOBS (2000). The methodological procedures were: application of the protocol developed by GEPLEC/UFPR, photographic images, films and semi-structured interviews. In conclusion, we can infer that some Barcelona's public spaces include such forms of corelated use, which depend on a number of factors, among them, urban planning, which should connect spaces in order to ensure diversity of experiences, safety, and therefore the public life in big cities.

La intención fue analizar el modelo de los parques, plazas y calles de Barcelona con énfasis en la relación entre las diferentes formas de apropriedad y la seguridad de estos espacios basados en los usos principales y combinados de JACOBS (2000). Los procedimientos metodológicos fueron: aplicación del protocolo desarrollado en el GEPLEC/UFPR, imágenes fotográficas y rodaje. Se concluyó que en Barcelona algunos espacios públicos contemplan tales formas de usos co-relacionados, los cuales dependen de una serie de factores. Entre estos, la planificación urbana, que también debe conectar espacios para garantizar la diversidad de experiencias, la seguridad, y, por lo tanto, la vida pública en las grandes ciudades.