Compartimos un nuevo artículo de investigación del grupo de investigación Genebso: «Minimal stories in Southeast Buenos Aires grasslands: carabid beetle biodiversity throughout an urban-rural gradient»
Urbanization modifies the original habitat and the biodiversity. Research throughout urban-rural gradients allows the monitoring of human activities on the biodiversity of native environments. Our aims were to a) record the diversity of edaphic coleopteran families and carabid species in native grassland remnants of urban, suburban and rural areas; b) identify potential taxa exclusively associated with urban and rural sites, respectively, or indifferent to such categorization; and c) compare the body sizes, wing morphology and trophic groups of carabid beetles in the three levels of urbanization. Our results showed that carabid species richness is higher in urban areas, but we found no difference in the number of families of edaphic coleopterans. One species, the eurytopic Argutoridius bonariensis, dominated in all areas; but in the suburban and rural areas it shared the dominance with stenotopic Argutoridius sp. N° 2. Carabid species assemblages did not exactly reflect the urban-rural gradient selected a priori. Regarding size variation, we found that large size species were more abundant in two urban sites; wing-dimorphic and apterous species were more abundant in urban areas. In reference to trophic groups, we recorded larger number of omnivores in the urban areas. We showed that some species can develop and survive in cities while others cannot, creating and sustaining a “new” urban ecosystem, with its own history, rules, dynamics and internal ecological memory.
Nuevo artículo de investigación: Indigenous arbuscular mycorrhiza and Trichoderma from systems with soybean predominance can improve tomato growth
Consolo, V. Fabiana
Barbieri, Pablo Andrés
Abstract: In the last decades, there has been a tendency towards sustainable agriculture. Following this trend, edaphic fungi as Trichoderma and arbuscular mycorrhizal fungi (AMF) could increase plant growth contributing to diminish agricultural chemical supply. However, little information exists in current research regarding the possible effects of alternative practices to soybean monoculture systems on fungal groups that could contribute to plant health and/or productivity. Thus, our objective was to assess changes in the abundance and diversity of indigenous AMF and Trichoderma from a long-term field experiment located in the Argentinean Pampas, in order to test the effect of alternative practices to soybean monoculture. The fungal ability to promote the growth of crops, such us tomato plant was also tested. Soil samples were collected from a soybean monoculture system (Sb), a system including cover crop (Avena sativa) followed by soybean (CC/Sb) and a system including rotations (rot) of SoybeanMaize-Wheat crops CC/Sb-rot, M-rot and W-rot, respectively. Highest AMF and Trichoderma abundance was found at W-rot and M-rot systems, and highest AMF diversity was found at W-rot and CC systems. Furthermore, highest mycorrhizal colonization was found at CC/Sb and W-rot systems. Inoculated plants with single AMF consortium or with Trichoderma strains showed significant increases in comparison with the control. Dual inoculation increased tomato plant growth as compared to the control, and evidence of synergism was found by increases in shoot and root growth. Our results show that dual inoculation with indigenous AMF and Trichoderma from alternative crop systems to soybean monoculture could play an important role in tomato plant growth. This information could be useful to decrease production costs and environmental impacts.
Crop rotation systems
Nuevo artículo de investigación: «Sucrose-to-ethanol microalgae-based platform using seawater» de los autores:
*M. Eugenia Sanz Smachetti, *Camila D. Coronel, Graciela Salerno & Leonardo Curatti
• Bioprospecting for native sucrose-accumulating microalgal strains
• Induction of sucrose and lipid accumulation using seawater
• Mild sugar-extraction conditions and direct conversion into ethanol
• Modeled productivity of 4200 L ethanol·ha−1·year−1 in raceway ponds in Brazil
Microalgal biomass is increasingly considered a promising feedstock for the production of bioethanol because it has simpler biochemical composition and structural features than plant feedstocks. However, it still requires hazardous and/or expensive acid or enzymatic saccharification processes before its conversion into ethanol by fermentation. To bypass this limitation, we identified microalgal strains that accumulate up to 10% (w/w) of sucrose, a readily fermentable sugar. Conditions were optimized to produce sucrose in half-strength seawater, as well as efficient extraction by very mild procedures, and conversion into ethanol. We present a model based on cultivation in environmental photobioreactors that predicted a productivity of 4200 L ethanol·ha−1·year−1 in raceway ponds in Brazil, approaching the average sucrose and ethanol productivity from sugarcane.