Some species of Leuconostoc are very important for fermented dairy products, as they contribute to the organoleptic characteristics of butter and cream, and also contribute to the formation of openings in some soft, semi-hard (Edam and Gouda cheeses), many artisanal or in blue-veined cheeses, such as Roquefort. In this study, 14 Leuconostoc strains isolated from cheese and cheese-related products were characterized by genotypic and phenotypic methods, and their technological performance assessed for their potential use as dairy adjunct starters. Phenotypic characterization allowed these strains to be classified to genus level, and genotypic studies (RAPD-PCR and 16S rRNA gene sequencing) identified them to species/ subspecies level. Five Leuconostoc strains grew well and acidified milk, and most of them grew even at 8°C. They showed moderate resistance to heat treatments (30 min at 63°C) and grew well in the presence of 3% and 4% NaCl, and were significantly inhibited at pH ≤ 5. All strains showed resistance against the bacteriophages tested. In general, the antibacterial properties observed were slight and due to acid production, with the exception of Leuconostoc citreum MB1, which strongly inhibited Listeria monocytogenes ATCC 15313 by the production of a bacteriocin-like compound. All Leuconostoc strains studied were susceptible to gentamicin, tetracycline, erythromycin and ampicillin. Some strains also showed interesting technological and antimicrobial properties, thus being potentially appropriate as adjunct starters in fermented dairy products. This study highlights that adventitious lactic acid bacteria can be a great source of novel strains with interesting technological features that could be used for fermented dairy foods.

Our aim was to investigate variability for salt tolerance in a collection of Panicum coloratum var. makarikariense of INTA EEA Rafaela, Argentina. Panicum coloratum is a C4 perennial grass to be potentially used to increase forage production in areas affected by abiotic factors which reduce their productivity. We evaluated the response of half-sib families from different accessions to increasing salt concentrations under growth chamber conditions. Germination percentage (GP), GP (% of control) and index of germination decreased with increasing salinity, while mean germination time increased (P˂0.001). After being exposed to saline conditions ungerminated seeds were able to recover in distilled water and many germinated. Salt tolerance was more variable between families within accessions than between accessions in all evaluated variables. At the seedling stage, morphological and physiological variables allowed differentiation among families on the basis of salt tolerance. Molecular characterization by ISSR molecular markers demonstrated variability within parent material and grouped families by accessions. A positive but low correlation between morphological and molecular distances was detected (r = 0.24; P = 0.032). Nonetheless, even after selection, enough molecular variability remained within tolerant families grouped by principal components analysis. In summary, materials of P. coloratum var. makarikariense from INTA EEA Rafaela showed both morphological and genetic variability for salinity tolerance and the contrasting genotypes could be used as parent materials to conduct breeding studies to improve salt tolerance in this species.