1,720,982 research outputs found
Fine mapping and gene expression analysis of de18, a defective endosperm mutant of maize affecting auxin metabolism
No full textThis paper reports the high resolution mapping of the defective endosperm 18 (de18) locus on chromosome 10 using SSR and AFLP markers. Expression data between the mutant de18 and its wild type De18 are also reported. Many genes involved in endosperm development and linked to auxin metabolism have been identified in kernels at four different developmental stages
Gene expression analysis in maize ears and silks after Fusarium verticillioides infection
No full textPhysiological and molecular analysis of drought response in two sweet sorghum genetypes.
No full textSweet sorghum is a multipurpose crop that, providing food, feed and fuel with a limited use of resources, responds to the criteria of modern agriculture and particularly to sustainable bioenergy production. It is a C4 plant adapted to marginal soils and semi-arid environments, characteristics that should be maintained and further improved in the process of obtaining new genotypes for bioenergy production . To understand the molecular and physiological basis of drought tolerance in sorghum, two genotypes (IS 19453 and Keller) were evaluated in a growth chamber experiment. Drought stress started when plants had consumed 80% of transpirable soil water. Total RNA was extracted from irrigated and not irrigated plants at 3 levels of water stress, and gene expression analysis was carried out using microarray technique. In both genotypes the number of differentially expressed genes increased with the stress level. Most of the up regulated genes were involved in cell rescue, transport, nucleic acid binding, and in lipid, protein and sugar metabolism. In non-irrigated plants, at the higher stress level, 54 up-regulated genes presented levels of expression 2-5 fold higher with respect to control samples. Among these 54 genes, 12 were up-regulated from the onset of stress. Further experiments are being carried out to confirm gene expression analysis with q-RT PCR and to isolate candidate genes for drought tolerance
L’importanza dell’ossigeno per la vinificazione
No full textGli accorgimenti per una corretta gestione del processo produttivo. L’imbrunimento dei bianchi è uno degli
inconvenienti più temut
Microarray analysis of differentially expressed mRNAs and miRNAs in young leaves of sorghum under dry-down conditions
No full textSorghum is a C4 plant adapted to semi-arid environments, and characterized by high water-use efficiency.
To better understand the molecular and physiological basis of drought response the sorghum genotype
IS19453, selected as a drought tolerant line during field trials, was evaluated in a “dry-down” experiment
under controlled conditions. The incoming stress was monitored by determining the water potential
available for 4-leaf-old plants. Control plants were maintained at approximately 2.5 pF, while water
stressed plants were sampled at 3.12, 3.65 and 4.14 pF. Transcriptome analysis was monitored using a
high density microarray containing all available sorghum TC sequences. Drought affected gene expression
at 4.14 pF; 1205 genes resulted up-regulated. Most of the differentially expressed genes were involved
in regulation of transcription (bZIPs, MYBs, HOXs), signal transduction (phosphoesterases, kinases, phosphatases),
carbon metabolism (NADP-ME), detoxification (CYPs, GST, AKRs), osmoprotection mechanisms
(P5CS) and stability of protein membranes (DHN1, LEA, HSPs). Several of them could be located in stay
green QTLs. Eight were selected and validated by qRT-PCR. A dedicated miRNA microarray allowed the
identification of four families of miRNAs up-regulated in the earlier phase of stress, while one family
was down-regulated. The selected drought related genes could be used to screen for potential drought
tolerance in other sorghum genotypes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Evaluation of broad spectrum sources of resistance to Fusarium verticillioides and advanced breeding lines
No full textFusarium verticillioides is the fungus commonly associated with maize production in temperate regions of the world, producing ear rot and contamination of grain by fumonisins. Genetic resistance is the best preventive action against fumonisins contamination, although no commercial maize hybrids are completely resistant at present. Several studies of the relationship between Fusarium and other species producing ear rot suggest that these fungal species interact in similar ways with the host plant. Consequently, host plant resistance to one pathogen could be associated with resistance to another. The aim of this study was to introduce sources of resistance to Fusarium spp. into maize inbred lines and to evaluate ear rot severity and fumonisin B1 contamination in advanced breeding lines and hybrids after artificial and natural infection with F. verticillioides. Two inbred lines (Co430 and Mp420) with resistance to kernel infection by F. graminearum and A. flavus, respectively, were crossed and backcrossed to susceptible inbred 1203. The BC1S1 progenies were evaluated for plant morphology and silk date and the selected S1 plants were self-pollinated. The S2 families were evaluated under artificial and natural infection with F. verticillioides. Selected S2 progenies were grown ear-to-row until S5-derived inbreds were developed. The S5 lines were evaluated under artificial and natural infection and used as males to produce single crosses. In both crosses, the mean ear rot of the S5 lines with the lowest ear rot was not significantly different from the resistant parent means. Significant progress was observed in the hybrids regarding ear rot performance: on average, ear rot severity decreased significantly from 23% in check hybrids to 5.3% in Co430-derived hybrids. Our results suggest that inbred lines bred for resistance to A. flavus and F. graminearum ear rot could be used to select advanced breeding lines with increased resistances to F. verticillioides ear rot
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