Lyophilized biopolymeric beads of chitosan-xanthan with edible fungus Laccaria laccata (Scop.) Cooke as forest ectomycorrhizal biofertilizers

Objective: To evaluate whether the spores of the edible fungus Laccaria laccata (Scop.) Cooke encapsulated in a freeze-dried biopolymeric matrix of chitosan-xanthan are capable of causing ectomycorrhization in Pinus greggii Englem. trees in grenhouse. Methodology: Pearls were made with the biopolymer chitosan-xanthan, in which spores of the edible ectomycorrhizal fungus L. laccata were encapsulated. Embedded spores were analyzed using scanning electron microscopy to assess possible structural damage. Subsequently, these pearls were used as biofertilizers in a greenhouse bioassay using Pinus greggii plants to evaluate their ability to be ectomycorrhized. The bioassay lasted 270 days, when it was evaluated in order to check if there was ectomycorrhizal colonization, using stereoscopic and bright field microscopy. Additionally, it was evaluated if there was an increase in terms of growth in inoculated plants compared to non-inoculated plants 180 and 270 days after sowing. Results: The encapsulated spores of L. laccata in the biopolymeric matrix formed ectomycorrhizae in the P. greggii roots. The percentages of ectomycorrhizal colonization in the plants varied from 80 to 90%, demonstrating that the production of biopolymeric pearls with chitosan-xanthan are capable of maintaining the viability of the spores of the ectomycorrhizal fungus evaluated, and of extensively colonizing the roots of Pinus greggii. Limitations on study /Implications: Pearls encapsulated in a biopolymeric matrix containing spores of the fungus L. laccata are capable of inducing ectomycorrhization in trees of forest importance. Conclusions: Encapsulated spores of an edible ectomycorrhizal fungus in the chitosan-xanthan biopolymer have potential as a forest biofertilizer, which opens the opportunity for industrial scaling.Objective: To evaluate whether or not the spores of the edible fungus Laccaria laccata (Scop.) Cooke encapsulated in a lyophilized biopolymeric matrix of chitosan-xanthan can cause ectomycorrhization in Pinus greggii Englem. trees under greenhouse conditions. Methodology: Spores of the edible ectomycorrhizal fungus L. laccata were encapsulated in beads made with the chitosan-xanthan biopolymer. The embedded spores were analyzed using scanning electron microscopy to evaluate possible structural damage. Next, these beads were used as biofertilizers in a greenhouse bioassay using Pinus greggii plants to evaluate their ability to be ectomycorrhized. The bioassay lasted 270 days. Subsequently, stereoscopic and bright field microscopy was used to determine if the roots of the pines had been subjected to an ectomycorrhizal colonization. Additionally, the growth of inoculated plants was evaluated compared to non-inoculated plants, 180 and 270 days after sowing. Results: The spores of L. laccata encapsulated in the biopolymeric matrix formed ectomycorrhizae in the roots of P. greggii. The percentages of ectomycorrhizal colonization in the plants ranged from 80 to 90%, demonstrating that the production of chitosan-xanthan biopolymeric beads can maintain the viability of the spores of the ectomycorrhizal fungus evaluated and extensively colonize the roots of Pinus greggii. Study Limitations/Implications: The biopolymeric matrix beads that contain spores of the fungus L. laccata can induce ectomycorrhization in trees of forest importance. Conclusions: The spores of an edible ectomycorrhizal fungus encapsulated in the chitosan-xanthan biopolymer have potential as a forest biofertilizer, which opens the opportunity to scale its use up to an industrial level

Análisis de la evolución del clima y los pastizales naturales en el noroeste de la provincia de Chubut, Argentina, durante el período 2000-2014: identificación de variables asociadas a la disminución de las existencias ganaderas en la región

Una elevada proporción del territorio argentino corresponde a tierras secas y una tercera parte de éstas se hallan en la Patagonia. Esta región históricamente ha sufrido procesos de deterioro del pastizal. Generalmente, la degradación es atribuida al uso ganadero; sin embargo, el efecto del clima sobre estos sistemas ha sido poco analizado. El objetivo de este trabajo fue analizar la evolución del clima y de los pastizales naturales, a través de la identificación de variables que permitan comprender los posibles cambios en las existencias ganaderas para el noroeste de la provincia de Chubut, en el período 2000-2014. Para ello se analizaron diferentes tipos de datos: climáticos, índice verde normalizado (NDVI), lecturas de monitores MARAS y existencias ganaderas. Los resultados indican incrementos de temperatura y tendencias negativas de la productividad y estructura del pastizal. Asimismo se observó una disminución de las existencias ganaderas. El incremento de las temperaturas podría estar relacionado con balances hídricos desfavorables, los cuales, combinados con el sobrepastoreo, pueden ser factores claves en los procesos de deterioro del pastizal. Resulta fundamental continuar con el monitoreo de las diferentes variables que caracterizan a estos sistemas y diseñar estrategias que permitan mitigar los procesos descriptos.Most of Argentina territory is classified as dry lands, one third of them is located in Patagonia. The grasslands in this region have been historically affected by deterioration. This degradation has been associated to excessive grazing. However, little attention has been paid to the effect of climate on these systems. The aim of this work was to examine the evolution of climate and grasslands in NW Chubut between 2000-2014, identifying variables that allow a better understanding of the causes of changes in livestock numbers. Different types of data have been analysed: weather statistics, normalized difference vegetation index (NDVI), information from MARAS monitors and livestock numbers. Results show a temperature increase and negative trends of grasslands productivity and structure during the period. Additionally, a decline in the livestock numbers was observed. Rising temperatures could negatively affect hydric balance which, along with overgrazing, could be key factors affecting grassland deterioration. It is of fundamental importance to keep monitoring these variables and to devise mitigation strategies against the processes described.EEA EsquelFil: Garcia Martinez, Guillermo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Ciari, Georgina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Gaitán, Juan José. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Caruso, Cecilia Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Nagahama, Nicolas, Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Opazo, Walter Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Nakamatsu, Viviana Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; ArgentinaFil: Lloyd, Carlos Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Antiman Cotut, Camila Rosa. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Irisarri, Gonzalo. Universidad de Buenos Aires. Facultad de Agronomía. Laboratorio de Análisis Regional y Teledetección; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Escobar, Juan Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; Argentin

Diagnóstico de la evolución del clima, los pastizales naturales y las cargas ganaderas para el noroeste de la provincia de Chubut en el período 2000-2014

En este artículo se presenta un diagnóstico sobre la evolución del clima, los pastizales naturales y las cargas ganaderas para el noroeste de la provincia de Chubut en el período 2000-2014. El análisis abarca los departamentos de Cushamen, Futaleufú, Languiñeo y Tehuelches.EEA EsquelFil: Garcia Martinez, Guillermo Carlos. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Ciari, Georgina. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Gaitán, Juan José. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Opazo, Walter Javier. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Caruso, Cecilia Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Nagahama, Nicolas, Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Nakamatsu, Viviana Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; ArgentinaFil: Lloyd, Carlos Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Antiman Cotut, Camila Rosa. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Esquel; ArgentinaFil: Irisarri, Gonzalo. Universidad de Buenos Aires. Facultad de Agronomía. Laboratorio de Análisis Regional y Teledetección; Argentina. Consejo Nacional de Investigaciones Científicas y Tecnológicas; ArgentinaFil: Escobar, Juan Maria. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Chubut; Argentin

Recuperación de agua de efluentes de una industria de cereales utilizando membranas

Para recuperar agua de re ú so en actividades industriales, se evaluó el proceso de filtración tangencial con membranas de efluentes previamente tratados por métodos biológicos en la planta experimental del Centro Interamericano de Recursos del Agua (CIRA). Entre las características del efluente destacan una alta turbiedad, la presencia de dos colorantes sintéticos de uso alimenticio, azul brillante y tartrazina, que son causantes de varias cortinas de coloración verde, además del contenido de sales y materia orgánica con valores de DQO aún altos para considerar el re ú so del agua. En la evaluación del proceso de filtración fueron probadas dos membranas cerámicas con umbral de corte de 150 y 15 kDa, y dos poliméricas de fibra hueca con 50 y 13 kDa, integradas individualmente a un equipo de filtración a escala piloto. En cada proceso se determinó el efecto de la presión transmembrana, la velocidad de flujo de agua y las características de la membrana sobre los caudales de agua filtrada y la calidad obtenida. Los resultados mostraron que las membranas de 15 y 13 kDa fueron las más ef icientes en el tratamiento del efluente del CIRA para obtener parámetros de calidad en el agua requeridos para actividades industriales de limpieza de equipos y suministro de agua a calderas. Sin embargo, el flujo de agua recuperada del efluente fue mayor en la membrana de 13 kDa, alcanzando 35 Lh -1 m -2 de flujo de agua permeada durante 120 minutos. Mientras que la membrana más estable fue la de 15 kDa, recuperando 28 Lh -1 m -2 de agua durante 190 minutos, sin problemas de polarización

Decoupling of soil nutrient cycles as a function of aridity in global drylands

The biogeochemical cycles of carbon (C), nitrogen (N) and phosphorus (P) are interlinked by primary production, respiration and decomposition in terrestrial ecosystems. It has been suggested that the C, N and P cycles could become uncoupled under rapid climate change because of the different degrees of control exerted on the supply of these elements by biological and geochemical processes. Climatic controls on biogeochemical cycles are particularly relevant in arid, semi-arid and dry sub-humid ecosystems (drylands) because their biological activity is mainly driven by water availability. The increase in aridity predicted for the twenty-first century in many drylands worldwide may therefore threaten the balance between these cycles, differentially affecting the availability of essential nutrients. Here we evaluate how aridity affects the balance between C, N and P in soils collected from 224 dryland sites from all continents except Antarctica. We find a negative effect of aridity on the concentration of soil organic C and total N, but a positive effect on the concentration of inorganic P. Aridity is negatively related to plant cover, which may favour the dominance of physical processes such as rock weathering, a major source of P to ecosystems, over biological processes that provide more C and N, such as litter decomposition. Our findings suggest that any predicted increase in aridity with climate change will probably reduce the concentrations of N and C in global drylands, but increase that of P. These changes would uncouple the C, N and P cycles in drylands and could negatively affect the provision of key services provided by these ecosystems

Plant Species Richness and Ecosystem Multifunctionality in Global Drylands

Experiments suggest that biodiversity enhances the ability of ecosystems to maintain multiple functions, such as carbon storage, productivity, and the buildup of nutrient pools (multifunctionality). However, the relationship between biodiversity and multifunctionality has never been assessed globally in natural ecosystems. We report here on a global empirical study relating plant species richness and abiotic factors to multifunctionality in drylands, which collectively cover 41% of Earth's land surface and support over 38% of the human population. Multifunctionality was positively and significantly related to species richness. The best-fitting models accounted for over 55% of the variation in multifunctionality and always included species richness as a predictor variable. Our results suggest that the preservation of plant biodiversity is crucial to buffer negative effects of climate change and desertification in drylands