M Alfonso

Publications (3)8.11 Total impact

• Source

  Available from: Lucia Ramirez

  Article: Identification of Prosopis juliflora and Prosopis pallida Accessions Using Molecular Markers

  G. Landeras, M. Alfonso, N. M. Pasiecznik, P. J. C. Harris, L. Ramírez
  [show abstract] [hide abstract]
  ABSTRACT: There has been much taxonomic confusion over the identification of Prosopis species, especially where introduced. Prosopis juliflora is the most widespread species in the arid and semi-arid tropics, although it has been confused with other species, particularly the closely related Prosopis pallida. In this study, RAPDs markers were used for the first time to distinguish between these species. Eighteen primers were used in amplification reactions, which yielded an average of 120 bands per accession. A dendrogram showing genetic similarities among accessions was constructed using UPGMA cluster analysis and the Nei and Li similarity coefficient. The genetic similarity observed between P. juliflora and P. pallida is similar to the value in sympatric Prosopis species in North America, and reconsideration of the series rank in section Algarobia is suggested. Species-specific markers confirmed that material in Burkina Faso is P. juliflora, but suggested that material collected in Brazil, Cape Verde and Senegal is P. pallida, whereas this has previously been identified as P. juliflora.
  Biodiversity and Conservation 04/2006; 15(5):1829-1844. · 2.24 Impact Factor
• Article: Relationship between monokaryotic growth rate and mating type in the edible basidiomycete Pleurotus ostreatus.

  L M Larraya, G Pérez, I Iribarren, J A Blanco, M Alfonso, A G Pisabarro, L Ramírez
  [show abstract] [hide abstract]
  ABSTRACT: The edible fungus Pleurotus ostreatus (oyster mushroom) is an industrially produced heterothallic homobasidiomycete whose mating is controlled by a bifactorial tetrapolar genetic system. Two mating loci (matA and matB) control different steps of hyphal fusion, nuclear migration, and nuclear sorting during the onset and progress of the dikaryotic growth. Previous studies have shown that the segregation of the alleles present at the matB locus differs from that expected for a single locus because (i) new nonparental B alleles appeared in the progeny and (ii) there was a distortion in the segregation of the genomic regions close to this mating locus. In this study, we pursued these observations by using a genetic approach based on the identification of molecular markers linked to the matB locus that allowed us to dissect it into two genetically linked subunits (matBalpha and matBbeta) and to correlate the presence of specific matBalpha and matA alleles with differences in monokaryotic growth rate. The availability of these molecular markers and the mating type dependence of growth rate in monokaryons can be helpful for marker-assisted selection of fast-growing monokaryons to be used in the construction of dikaryons able to colonize the substrate faster than the competitors responsible for reductions in the industrial yield of this fungus.
  Applied and Environmental Microbiology 09/2001; 67(8):3385-90. · 3.83 Impact Factor
• Source

  Available from: Lucia Ramirez

  Article: Use of molecular markers to differentiate between commercial strains of the button mushroom Agaricus bisporus.

  L Ramírez, V Muez, M Alfonso, A García Barrenechea, L Alfonso, A G Pisabarro
  [show abstract] [hide abstract]
  ABSTRACT: Agaricus bisporus is an edible basidiomycete cultivated industrially for food production. Different spawn and mushroom producers use genetically related A. bisporus strains frequently marketed as different products. In this paper we show that the use of suitable molecular markers reveals the high level of genetic homology of commercial strains of A. bisporus, and allows, at the same time, to distinguish between them. In the course of this work, a molecular marker potentially linked to the agronomic character 'mushroom weight' has been identified by bulked segregant analysis.
  FEMS Microbiology Letters 05/2001; 198(1):45-8. · 2.04 Impact Factor