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The preservation of quality, sanity and nutritional value of the seeds during the storage period depends not only on the conditions of production and harvesting, but the storage and maintenance of appropriate storage conditions of the product. The aim of this study was to evaluate the relationship between chemical composition, germination and sanity in seeds of landraces maize stored under different conditions. Lots of corn seeds of the varieties Oito Carreiras, Cabo Roxo and Lombo Baio were used. The seeds were stored for nine months in paper bags at temperature of 10°C in a laboratory / cold chamber (condition 1) and in plastic packaging atmosphere at room temperature (condition 2). Germination test, sanity and chemical composition analysis were performed. The seed quality is affected by changes in the chemical composition during storage. Fungi incidence is related to the chemical composition of the seeds is changed during the storage period. [ABSTRACT FROM AUTHOR]

The preservation of quality, health and nutritional value of the seeds during the storage period depends not only on the conditions of production and harvesting, but the storage and maintenance of appropriate storage conditions of the product. Thus, the aim of this study was to analyze the chemical composition of seeds of landraces maize stored under different conditions. Seeds of three maize varieties Oito Carreiras, Cabo Roxo and Lombo Baio were analyzed in relation to the contents of ash, crude protein, lipids, fatty acids, total dietary fiber, soluble and insoluble, and carbohydrates. From the results it was concluded that the content of crude protein, fat and saturated fatty acids decreased with storage and that the chemical composition of the seeds of landraces of maize did not vary with the storage condition. The chemical composition of stored seeds is modified in intensity and variable speed as it progresses deterioration in reserve substances, respiratory rate, synthesis and activity of enzymes can occur, all with direct influence on the chemical composition of the seeds. [ABSTRACT FROM AUTHOR]

The article provides information on a survey of 16 pecan or Carya illinoinensis orchards in southern Brazil to determine the causal agent of a small black circular leaf spot disease. Topics include findings on morphological features and sequence homology, inoculation of young detached leaflets to confirm pathogenicity, and the emergence of black leaf spots after 22 days on all inoculated leaflets.

The objective of this study was to characterize species of the Cladosporium cladosporioides complex isolated from pecan trees (Carya illinoinensis) with symptoms of leaf spot, based on morphological and molecular approaches. Morphological attributes were assessed using monosporic cultures on potato dextrose agar medium, which were examined for mycelial growth, sporulation, color, and conidia and ramoconidia size. Molecular characterization comprised isolation of DNA and subsequent amplification of the translation elongation factor 1α (TEF-1α) region. Three species of the C. cladosporioides complex were identified: C. cladosporioides, Cladosporium pseudocladosporioides, and Cladosporium subuliforme. Sporulation was the most important characteristic differentiating species of this genus. However, morphological features must be considered together with molecular analysis, as certain characters are indistinguishable between species. TEF-1αcan be effectively used to identify and group isolates belonging to the C. cladosporioides complex. The present study provides an important example of a methodology to ascertain similarity between isolates of this complex causing leaf spot in pecan trees, which should facilitate future pathogenicity studies.

The occurrence of Fusarium spp associated with pecan tree (Carya illinoinensis) diseases in Brazil has been observed in recent laboratory analyses in Rio Grande do Sul State. Thus, in this study, we i) obtained Fusarium isolates from plants with disease symptoms; ii) tested the pathogenicity of these Fusarium isolates to pecan; iii) characterized and grouped Fusarium isolates that were pathogenic to the pecan tree based on morphological characteristics; iv) identified Fusarium spp to the species complex level through TEF-1α sequencing; and v) compared the identification methods used in the study. Fifteen isolates collected from the inflorescences, roots, and seeds of symptomatic plants (leaf necrosis or root rot) were used for pathogenicity tests. Morphological characterization was conducted using only pathogenic isolates, for a total of 11 isolates, based on the mycelial growth rate, sporulation, colony pigmentation, and conidial length and width variables. Pathogenic isolates were grouped based on morphological characteristics, and molecular characterization was performed by sequencing TEF-1α genes. Pathogenic isolates belonging to the Fusarium chlamydosporum species complex, Fusarium graminearum species complex, Fusarium proliferatum, and Fusarium oxysporum were identified based on the TEF-1α region. Morphological characteristics were used to effectively differentiate isolates and group the isolates according to genetic similarity, particularly conidial width, which emerged as a key morphological descriptor in this study.