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    Soluble solids content in the stalk of maize (Zea mays L.) lines and hybrids

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    The present interest for sugar rich crops as potential energy sources, add new reasons to explore the variability for soluble sugar content in stalk of maize genotypes /Zea mays). A total of 218 entries was evaluated, evidencing a high variability (from 5 to 16% Brix) likely useful for breeding programs

    DIFFERENTIAL MODULATION OF PLANT AND FUNGAL PHOSPHATE TRANSPORTERS AND EXPRESSION OF MYCELIAL TRAITS IN DIVERSE MYCORRHIZAL MAIZE INBRED LINES

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    Current food crop production systems are heavily dependent on the use of chemical fertilizers, of which those containing phosphorus (P), essential for plant growth and development, represent a non-renewable mineral resource whose reserves are estimated to decline within 100-200 years. The microbiota associated with plant roots, mainly represented by arbuscular mycorrhizal fungi (AMF) can be exploited for reducing external P input into agro-ecosystems. In this study, plant and fungal variables involved in P acquisition were investigated in four maize inbred lines (Oh40B, Mo17, Oh43 and B73), differing for mycorrhizal responsiveness and low-P tolerance, when inoculated with the symbiont Rhizoglomus irregulare. The expression patterns of genes encoding phosphate transporters (PTs) in extraradical and intraradical mycelium (ERM and IRM) and in maize roots were assessed along with plant growth responses, P uptake and ERM extent and structure. The four maize lines differed in expression levels of PT genes in both plant and fungal tissues, in ERM phenotypic traits and plant performance. Expression of PT genes in roots and ERM of the low-P tolerant maize line Mo17 was higher than that detected in the low-P susceptible line B73, which revealed larger ERM hyphal densities and interconnectedness. Significant correlations were found between ERM structural traits, and both expression levels of PT genes and mycorrhizal host benefit data. Further studies aimed at improving our knowledge of the genetic mechanisms regulating the functioning of AMF symbiosis may lead to the development of new strategies of targeted molecular breeding to obtain more sustainable low-P tolerant crops

    THE CRISPR/CAS9 EDITING OF A WRKY GENE AND THE OVEREXPRESSION OF A LIPOXYGENASE GENE FOR IMPROVING PATHOGEN RESISTANCE IN MAIZE

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    Fusarium verticillioides (Fv) is a major cereal pathogen causing stalk rot and ear rot in maize, negatively affecting crop productivity, and compromising food safety by producing the secondary metabolites fumonisins. Several studies were conducted to identify maize genes associated with host plant resistance to Fv infection and fumonisin accumulation. The maize WRKY transcription factors and the lipoxygenases (ZmLOXs) are well recognized as important players in plant defense against pathogens, and it is known that the host-pathogen lipid cross-talk influences the pathogenesis. In this regard, previous RNA-seq experiments reported the enhanced expression of ZmLOX genes in maize resistant genotypes and GWAS resulted in one SNP significantly associated with ZmWRKY125. The Clustered Regularly Interspaced Short Palindromic Repeat/associated Cas9 (CRISPR/Cas9) editing of ZmWRKY125 and the transgenic overexpression of ZmLOX4 genes were carried out to investigate the possible implication of these two genes in the resistance mechanisms against Fv. Before cloning experiments, protein domain conservation and different splicing products have been analyzed comparing homologues and orthologues for both genes. As regards ZmWRKY125, the CRISPR cloning was based on a double cloning using two different guides (sgRNA) for one gene target. Agrobacterium tumefaciens mediated transformation was used for introducing the construct under the maize promoter ZmpUBI in the binary vector p1609 in maize A188 line. Mutants from three different transformation events were obtained. For each event, T2 plants will be genotyped to find homozygous for the mutation that in turn will be phenotyped for Fv resistance and fumonisin content. As regards ZmLOX4, the gene was cloned under an overexpressed promoter involved in kernel development in the vector L1781, and the same transformation conditions adopted for the CRISPR/Cas9 editing of ZmWRKY125 were used. Mutants from two different transformation events were obtained. For each event, T2 plants were genotyped in order to find homozygous for the mutation. Homozygous plants will be further evaluated for Fv resistance, fumonisin accumulation, oxylipin content as well as for the expression analysis of the main genes involved in the jasmonic acid pathway

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Rural resistance and popular protest in Marocco : A study of the tribal rebellion of 1911

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    Burke Edmund. Rural resistance and popular protest in Marocco : A study of the tribal rebellion of 1911. In: Revue de l'Occident musulman et de la Méditerranée, n°13-14, 1973. Mélanges Le Tourneau. I. pp. 193-206
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