http://hdl.handle.net/11336/325 Articulos de PLANTA PILOTO DE PROC.IND.MICROBIOLOGICOS (I) Fri, 05 Apr 2024 20:59:44 GMT 2024-04-05T20:59:44Z http://hdl.handle.net/11336/231778 Egg parasitoid assemblages and their effectiveness against the Lepidoptera soybean defoliators in Argentina's subtropical production region Valverde, Liliana; Van Nieuwenhove, Guido Alejandro; Virla, Eduardo Gabriel Soybean, Glycine max (L.) Merr. (Fabaceae), is one of the most important crops worldwide, but caterpillars of various species (Lepidoptera) may greatly reduce its annual yield. Nowadays, the main method of controlling these pest species is based on the use of broad-spectruminsecticides, which are harmful to human health and increase environmental contamination. Therefore, other sustainable methods of control, such as biological control, are in increasing demand. The present study aimed to identify the egg parasitoid species that attack lepidopterans defoliating soybeans in South America's subtropical regions, as well as evaluate their effectiveness at various stages of soybean development. The research was conducted in a commercial soybean field (80 ha) located in Tucumán, Argentina, which was surrounded by wild vegetation as a way to promote biological control. Every week, throughout three consecutive soybean seasons, 20 soybean plants were randomly selected and brought to the laboratory in search of lepidopteran eggs. Over the course of the three crop seasons, the soybean plants were attacked by Anticarsia gemmatalis Hübner (Erebidae), Rachiplusia nu (Guenée), and Chrysodeixis includens (Walker) (both Noctuidae). Six egg parasitoid species were identified, but only three of them were frequently found during the current study. Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) was the most predominant species attacking all lepidopteran pests across all soybean phenological stages. Encarsia porteri (Mercet) (Hymenoptera: Aphelinidae) preferred to attack R. nu eggs, whereas Telenomus cyamophylax Polaszek (Hymenoptera: Scelionidae) parasitized only A. gemmatalis and R. nu eggs. Despite the use of insecticides in the soybean field, the parasitism rates recorded were high. This suggests that using conservation tactics such as native vegetation patches and surrounding alternative crops may result in higher rates of natural control. Fri, 01 Mar 2024 00:00:00 GMT http://hdl.handle.net/11336/231778 2024-03-01T00:00:00Z http://hdl.handle.net/11336/231053 GIS-based methodology for mapping and modeling microbialite deposits in high mountain lakes and wetlands of Central Andes (Catamarca, Northwestern Argentina) Villafañe, Patricio Guillermo; Cónsole Gonella, Carlos Alfredo; Farias, Maria Eugenia; Ahumada, Luis Gabriel; Ruiz Sánchez, Francisco Javier Modern microbialites in Argentina’s Puna (Central Andes) are considered a reliable tool for understanding the evolution of early life on our planet and developing strategies fordetecting life on Mars. The morphological, structural and geochemical variations in these deposits, together with their distribution and architecture, are some of the most important parameters for understanding and characterising them. However, the lack of appropriate cartography and/or thehigh price to access it, added to the complex geological and geomorphological context in this region, complicate a traditional mapping on a good scale of detail. This paper presents a GIS-based methodology for a detailed mapping and architectural modeling of Las Quínoas microbialiticdeposit (Holocene). To meet this objective, the geoprocessing of the information obtained from drone surveys, fieldwork and laboratory work, is carried out using ArcGIS software. The result is a high-resolution reconstruction of the deposit architecture, together with several thematic mapsthat represent the variation of the morphological, structural and geochemical characteristics of the oncoids (microbialites) with respect to depth and their position in the water body. From an integral point of view, this work provides a new methodological approach for microbialites mapping and improves the survey strategies in Central Andes. Thu, 01 Sep 2022 00:00:00 GMT http://hdl.handle.net/11336/231053 2022-09-01T00:00:00Z http://hdl.handle.net/11336/225019 Microbial Biopesticides: Diversity, Scope, and Mechanisms Involved in Plant Disease Control Vero, Silvana; Garmendia, Gabriela; Allori Stazzonelli, Enzo; Sanz, José María; Gonda, Mariana; Alconada Magliano, Teresa Maria; Cavello, Ivana Alejandra; Dib, Julian Rafael; Diaz, Mariana Andrea; Nally, Maria Cristina; Pimenta, Raphael Sanzio; Fonseca Moreira da Silva, Juliana; Vargas, Marisol; Zaccari, Fernanda; Wisniewski, Michael Food losses, defined as a reduction in the quantity and quality of food during production and storage, impact food safety and security. Losses caused by plant pathogens are among the most significant. Chemical pesticides have been extensively used to prevent microbial diseases. Their toxicity and reduced efficacy, however, have encouraged investigators to develop alternatives. Alternatives based on microbial biopesticides tend to be safer and more environmentally benign than conventional pesticides. In recent years, formulations based on biopesticides have progressively increased in number and diversity and have attracted commercial interest. Understanding the mechanisms by which biopesticides control the disease is fundamental to achieving optimal disease control. Biocontrol mechanisms can be divided into two main categories: those related to the ability to inhibit pathogens or their virulence factors, and those that enhance host plant fitness and induce disease resistance. Here, the first type of strategy is reviewed, which is directly mediated by physical contact between biocontrol agents and pathogens or indirectly by exposure of a pathogen to antimicrobial or microbial-inhibiting compounds produced by the microbial antagonist. Mechanisms involving physical contact include mycophagy, destruction of pathogenic bacteria by bacteriophages or predation, and disease inhibition by topical applications of specific dsRNA. Indirect mechanisms that do not involve direct contact with a pathogen include the production of antimicrobial compounds, competition, and virulence factor suppression by quorum quenching. These topics are reviewed and discussed. Wed, 01 Mar 2023 00:00:00 GMT http://hdl.handle.net/11336/225019 2023-03-01T00:00:00Z http://hdl.handle.net/11336/225017 Conversion of sugarcane vinasse into biomass of Aspergillus sp. V1 and its potential application as a fish feed ingredient del Gobbo, Luciana Melisa; Pérez Iglesias, Juan Manuel; Almeida, César Américo; Villegas, Liliana Beatriz; Colin, Veronica Leticia Vinasse generated by bioethanol industry is the acid liquid waste with high content of organic matter that causes undesirable impacts when it is poured into the ecosystem, indiscriminately. Therefore, the development of new technologies to improve the vinasse management is relevant worldwide. As a possible alternative, in this study, conversion of sugarcane vinasse into biomass of Aspergillus sp. V1 for use as a cheap fish feed ingredient was evaluated. Vinasse toxicity was also monitored, before and after biomass production, using growth parameters in Lactuca sativa as endpoints. Biomass of Aspergillus sp. V1 produced from vinasse supplemented with 2 g/L urea revealed a nutritional composition within recommended levels for fish diets, and an aflatoxins concentration of 12.9 µg/kg, which was within permissible levels for animal feeds. Fish feeding assays with 50 % and 100 % fungus biomass did not demonstrate any adverse effects for Poecilia reticulata, used as a model organism. Finally, inhibitory concentration (IC50) on L. sativa root elongation was 11.7 % for initially received vinasse and 23.8 % for vinasse resulting from biomass production. These findings demonstrate that it is feasible to minimize the transfer of distilleries pollution to the environment through biological conversion of vinasse into fungal biomass with nutritional value. Fri, 01 Sep 2023 00:00:00 GMT http://hdl.handle.net/11336/225017 2023-09-01T00:00:00Z