Scorsetti, Ana Clara; Eliades, Lorena Alejandra; Stenglein, Sebastián A.; Cabello, Marta Noemí; Pelizza, Sebastián; Saparrat, Mario Carlos Nazareno
Tolypocladium cylindrosporum is an entomopathogenic fungi that has been studied as a biological control agent against insects of several orders. The fungus has been isolated from the soil as well as from insects of the orders Coleoptera, Lepidoptera, Diptera and Hymenoptera. In this study, we analyzed the ability of a strain of T. cylindrosporum, isolated from soil samples taken in Tierra del Fuego, Argentina, to produce hydrolytic enzymes, and to study the relationship of those activities to the fungus pathogenicity against pest aphids. We have made the traditional and molecular characterization of this strain of T. cylindrosporum. The expression of...
Hernández, Marcelo Paulo; Katinas, Liliana; Arambarri, Ana M.
In this paper we examine lipophilic substances, tannins, proteins, reducing carbohydrates, starch, and oxalate salts in early lineages of Asteraceae to test if they are a useful complement to classification studies. Styles of mature flowers of 44 species were processed according to plant histochemical techniques and observed by means of a light microscope. Lipophilic compounds were always present in the cuticle and cell walls, and in some species were located inside the cells. Proteins were located in the style cell walls and cell interior of most of the analyzed species. No tannins were found. In general, there is a correlation...
El presente artículo tiene como objetivo principal la aplicación de metodologías no destructivas, que utilicen muestras mínimas (micro muestras) para el reconocimiento de maderas en bienes culturales, el cual fue posible por la unión interdisciplinaria entre dos Universidades estatales de Argentina, la UNLP (Universidad Nacional de la Plata) y la UNSAM (Universidad Nacional de San Martin).
Faustino, Laura Inés; Bulfe, Nardia M. L.; Pinazo, Martín; Monteoliva, Silvia Estela; Graciano, Corina
Plants of Pinus taeda L. from each of four families were fertilized with N, P or N+P at planting. The H family had the highest growth in dry mass while the L family had the lowest growth. Measurements of plant hydraulic architecture traits were performed during the first year after planting. Stomatal conductance (gs), water potential at predawn (Ψpredawn) and at midday (Ψmidday), branch hydraulic conductivity (ks and kl) and shoot hydraulic conductance (K) were measured. One year after planting, dry weight partitioning of all aboveground organs was performed. P fertilization increased growth in all four families, while N fertilization...
Toledo, Andrea V.; Alippi, Adriana Mónica; Marino de Remes Lenicov, Ana María
The phytosanitary importance of the corn leafhopper, Dalbulus maidis (Delong and Wolcott) (Hemiptera: Cicadellidae) and the planthopper, Delphacodes kuscheli (Fennah) (Hemiptera: Delphacidae) lies in their ability to transmit phloem-associated plant pathogens, mainly viruses and mollicutes, and to cause considerable mechanical damage to corn plants during feeding and oviposition. Fungi, particularly some members of the Ascomycota, are likely candidates for biocontrol agents against these insect pests, but several studies revealed their failure to invade the insect cuticle possibly because of the presence of inhibitory compounds such as phenols, quinones, and lipids and also by the antibiosis effect of the microbiota living...
López, Silvina Marianela Yanil; Balatti, Pedro Alberto
The aim of this work was to identify closely related rhizobia, used to formulate commercial inoculants, using polymerase chain reaction (PCR). Repetitive extra-genic palindromic (REP) and BOX fingerprints hardly discriminate among a set of commercial strains. PCR targeted at repetitive RSα successfully allow discriminating within representatives of Bradyrhizobium. These fingerprints clustered isolates at a higher level of similarity and proved to be an important tool to complement the information provided by the other markers. The results suggest that mutants occur along the bacterial culture, during inoculant production. However, independently of the number of amplification reactions used to characterize and identify...