Selection in Base Population of Ornamental Peppers (Capsicum annuum L.)

Aims: The aim of this study was to characterize and select plants with ornamental potential and resistant to pathogens in generation F2. Study Design: For genetic divergence analysis, Tocher's grouping method was used, based on the standardized Euclidean distance. Analyses were carried out for the quantitative and qualitative data separately and also for the data together. In addition, the relative importance of the characteristics evaluated for genetic divergence was calculated using SINGH's Methodology (1981). All analyses were performed using the computational Genes program. Place and Duration of Study: The experiment was conducted in a greenhouse of the Plant Biotechnology Laboratory of the Center of Agrarian Sciences (CCA) of the Federal University of Paraíba (UFPB). The treatments consisted of 354 progenies, an F2 generation of ornamental peppers (Capsicum annuum L), belonging to the Germplasm Bank of UFPB, derived from the controlled self-fertilization of F1 and obtained from the crossing between the parents UFPB390 X UFPB137. Plants grown in vessels of 900 mL filled with commercial substrate. There was variability among genotypes for the evaluated characters. Methodology: Genotypes were characterized according to the descriptors for Capsicum suggested by IPGRI. 20 quantitative characters and 4 qualitative in ornamental peppers were evaluated. Leaves identified from an optical microscope using the illustrated descriptor of imperfect fungus. Results: The variability between genotypes was higher for qualitative characters related to disease resistance. It is possible to select individual plants for opening lines in Generation F3. 7 plants; 7; 15; 50; 69; 120; 155; 157; 196; 314; 326; 331; 347 should be selected for not presenting symptoms of fungi diseases. Conclusion: Greater diversity among genotypes was detected when the incidence of diseases in the plants was evaluated. The plants 7; 15; 50; 69; 120; 155; 157; 196; 314; 326; 331; 347 should be selected because they do not present symptoms of fungal diseases.

Pre-treatment of extracellular water soluble pigmented secondary metabolites of marine imperfect fungus protects HDF cells from UVB induced oxidative stress

The melanin precursor of fungal origin was found to be an excellent UVB inhibiting agent as experimented in HDF cells and in small animals.

Development of forecasting elements for minimization of fungicide treatment in potato protection against early blight in Moscow region

Early blight of potato (the agent is imperfect fungus Alternaria alternata (Fr.) Keissl.) is a serious disease of potatoes under hot conditions. This disease is important in the regions of Eastern and Southern Europe, Asia and Africa. It is controlled with intensive application of fungicides commonly used against late blight. However, currently fungicides cause undesirable damage to humans and the environment. Elements of forecasting the early blight have been developed in order to minimize the dosage of fungicides. Primary symptoms (chloroses and necroses) and the potential of pathogen natural inoculum (determination of disease severity, indexes of formation of conidia and aggressiveness; as well as the current weather conditions) were registered and determined in the potato signal plots (no treatments or artificial inoculation) near main potato cropping. Seed tubers of main potato cropping were preliminary treated with plant growth regulator Circon and micro-fertilizer Siliplant produced by the Russian Company NEST-M. These preparations proved to be effective in acceleration process of potato growth and in delaying the early blight onset by 5-10 days. The same potato cultivar must be planted both in signaling plots and in the fields. Well-timed determination of primary symptoms and potential of pathogen in?oculum allowed us to understand the damage that early blight can cause to potato natural inoculation, and hence to provide well-timed application of fungicides with optimum dosages in mixture with Circon or Silipant. This forecasting method can be helpful for the adequate management of early blight and decrease of the environmental damages.

Species diversity, abundance and dominance of macromycetes in beech forest stands

The aim of this paper is to contribute to the knowledge of dynamics of species diversity, abundance, distribution of fruiting bodies and dominance of macromycetes in mycocoenosis of beech monocultures. The problems were studied in beech monocultures on three permanent research plots with various impacts of air pollutants generated by the aluminium plant in Žiar nad Hronom. Over the research period we determined 121 macromycete species and one species of imperfect fungus. We found relatively balanced values of abundance, fruiting body distribution and species dominance on all the examined plots. The species diversity in groups consisting of the most dominant species was practically the same on each plot. As for the ecotrophic requirements of individual macromycetes, we can conclude that the diversity of tree parasites decreased with decreasing pollutant load. We also found out relatively balanced numbers of lignicolous saprophytes and terrestrial saprophytes on each research plot. Air pollutants also influenced the species spectrum of ectomycorrhizal macromycetes negatively (only 6 species on the plot with highest pollution stress and <br />21 species on the plot with lowest pollution stress).

Multiple non-ribosomal peptide synthetase genes determine peptaibol synthesis in Trichoderma virens

Trichoderma virens, an imperfect fungus, is used as a biocontrol agent to suppress plant disease caused by soilborne fungal pathogens. Antimicrobial peptides it produces include peptaibols of 11, 14, and 18 amino acids in length. These peptaibols were previously reported to be synthesized by a non-ribosomal peptide synthetase (NRPS) encoded by the Tex1 gene in strain Tv29-8. The present study examined the Tex1 homolog in a commercially relevant T. virens strain, G20. Although the gene in G20 was 99% identical in DNA sequence to Tex1 in the 15.8 kb compared, gene disruption results indicate that it is only responsible for the production of an 18-mer peptaibol, and not 11-mer and 14-mer peptaibols. Additional NRPS adenylate domains were identified in T. virens and one was found to be part of a 5-module NRPS gene. Although the multimodule gene is not needed for peptaibol synthesis, sequence comparisons suggest that two of the individual adenylate domain clones might be part of a separate peptaibol synthesis NRPS gene. The results indicate a significant diversity of NRPS genes in T. virens that is unexpected from the literature.Key words: Hypocrea virens, Gliocladium virens, Trichoderma virens.