Improvement of copper stress tolerance in pepper plants (<i>Capsicum annuum</i> L.) by inoculation with arbuscular mycorrhizal fungi

The effect of arbuscular mycorrhizal fungi (AMF) inoculation, on pepper plant growth and physiological parameters in response to increasing soil Cu concentrations was studied. Treatments consisted of inoculation or not with Funneliformis mosseae or Rhizophagus intraradices and the addition of Cu to soil at concentrations of 0, 2, 4 and 8 mM CuSO₄. The increase in copper concentration diminished the inoculation in all treatments. The highest experimental concentration of Cu (8 mM) reduced significantly the hyphae viability and ALP activity, regardless of the inocula used. The total dry weight and the leaf area were higher for mycorrhizal plants. The mycorrhizal dependence was 30 and 50% for plants inoculated with F. mosseae and R. intraradices, respectively at 8 mM CuSO4. The electrolyte leakage was higher at higher Cu concentrations, in roots and leaves. Net photosynthetic rates and transpiration were lower in plants treated with Cu, regardless of the inocula. At low Cu concentration in soil no differences were observed in Cu content in the shoots and roots. At 4 mM Cu, Cu content in roots was significantly higher than in shoots. At 8 mM Cu, in non-inoculated plants accumulate more Cu than inoculated plants in the roots, leaves and fruits regardless of the inocula. Beneficial microbial inoculants such as AMF, is an attractive strategy to farmers in the context of sustainable agriculture. Pre-inoculation in transplants could be an adequate practice to alleviate the deleterious effects in stress of pepper plants. However different AMF species can differ in their ability to minimize stress effects and promote plant growth.Instituto de Fisiología Vegeta

Quick growth of lettuce plants using purple led illumination devices

Background and Objective: As the world's population increases, efforts are to produce more food. The growth of vegetables requires a certain generation time that limits the amount obtained from them. The present study was initiated to evaluate the speed and capacity of lettuce plant growth in a red-blue LED sunless lighting model. Methodology: Lettuce seed were insert in 20 black plastic (polypropylene) seed beds 54×28 cm plates; each one with 288 alveoli (diameter 1.9 cm depth 3 cm). Plates were randomized in two groups (LED illumination or control sunlight group during 30 days)-10 plate each group-. Artificial lighting device consists of 6 LED modules (3 red and 3 blue LED modules) to form a purple color. Root length, plant height, relation height/root, number of leaves, aerial part of the plant and an index of greenery (SPAD unit) were variables included in the study. These variables were measured at the beginning of the experience and also at day 7th,15th and at day 21sth of the experience. Statistical method used was one way ANOVA using the Stat-graphics Centurion program. The mean values obtained were compared using the LSD test with a significance of p <0.05 with a confidence interval of 95%. Results: The number of leaf and root length was similar in both groups. Root length was similar. However, leaf area, leaf/root relation, overall height of plant and SPAD units were increased in LED lighting compared with sunlight growth. Conclusion: The purple LED lighting model is a valid option to induce lettuce production in sunless conditions.Facultad de Ciencias MédicasInstituto de Fisiología VegetalFacultad de Ingenierí

El trabajo en grupos heterogéneos como innovación didáctica: la experiencia del curso optativo de grado y abierto a la comunidad de Cultivo en Hidroponia en la Facultad de Ciencias Agrarias y Forestales

El curso de Cultivo en Hidroponia se desarrolla en la Facultad de Ciencias Agrarias y Forestales, UNLP. En este curso se identifica una importante heterogeneidad en los participantes, tanto en sus edades, como en sus capacidades y habilidades, ya que está dirigido a alumnos de grado, profesores de escuelas medias y miembros de la comunidad. Dadas las características del alumnado se observa como problemática la dificultad de algunos estudiantes para comprender los contenidos y de los docentes al buscar herramientas pedagógicas y didácticas que permitan incluir los intereses de cada alumno en particular, respondiendo a sus inquietudes, sin perder la dinámica del grupo ni los propósitos de enseñanza. Por cuestiones de tiempo, espacio y disponibilidad horaria, no es posible realizar distintos cursos en función de los objetivos de cada uno de los participantes, lo que nos coloca ante el desafío de desarrollar una propuesta de enseñanza globalizadora en la que todos se sientan incluidos. Para esto, se diseñó una propuesta de innovación que toma la diversidad como una potencialidad, y también como una dimensión a atender en virtud de garantizar estrategias metodológicas que posibiliten incluir diferentes trayectorias e intereses de formación.Especialización en Docencia UniversitariaFacultad de Humanidades y Ciencias de la EducaciónInstituto de Fisiología Vegeta

Quick growth of lettuce plants using purple led illumination devices

Background and Objective: As the world's population increases, efforts are to produce more food. The growth of vegetables requires a certain generation time that limits the amount obtained from them. The present study was initiated to evaluate the speed and capacity of lettuce plant growth in a red-blue LED sunless lighting model. Methodology: Lettuce seed were insert in 20 black plastic (polypropylene) seed beds 54×28 cm plates; each one with 288 alveoli (diameter 1.9 cm depth 3 cm). Plates were randomized in two groups (LED illumination or control sunlight group during 30 days)-10 plate each group-. Artificial lighting device consists of 6 LED modules (3 red and 3 blue LED modules) to form a purple color. Root length, plant height, relation height/root, number of leaves, aerial part of the plant and an index of greenery (SPAD unit) were variables included in the study. These variables were measured at the beginning of the experience and also at day 7th,15th and at day 21sth of the experience. Statistical method used was one way ANOVA using the Stat-graphics Centurion program. The mean values obtained were compared using the LSD test with a significance of p <0.05 with a confidence interval of 95%. Results: The number of leaf and root length was similar in both groups. Root length was similar. However, leaf area, leaf/root relation, overall height of plant and SPAD units were increased in LED lighting compared with sunlight growth. Conclusion: The purple LED lighting model is a valid option to induce lettuce production in sunless conditions.Facultad de Ciencias MédicasInstituto de Fisiología VegetalFacultad de Ingenierí

Comprehensive analysis of Nematode–Tomato Plant–Mycorrhizal Fungus system for bio based product development

Nacobbus aberrans is a plant parasitic nematode that causes significant economic losses in the American Continent and is considered a quarantine pest in many countries. Some arbuscular mycorrhizal fungi have shown the ability to reduce the population of this pathogen; however, most studies do not consider other relevant aspects that have to do with the crop or the fungus. The purpose of this work was to select an isolated mycorrhizal fungus based on a comprehensive analysis of the Nematode–Plant–Mycorrhizal Fungus system. The test was conducted on Solanum lycopersicum L. grown in pots. The evaluated isolates were Funneliformis mosseae, Rhizoglomus intraradices A2, and Rhizoglomus intraradices B1. All the isolates reduced the nematode population significantly; however, differences in the content of photosynthetic pigments, soluble proteins, and osmoregulatory metabolites were identified. All of these impacted on the photosynthetic rates of the different treatments. There were also differences in the growth of the fungi within the roots, and in the viability of the fungal structures. The comprehensive analysis of the plant–nematode–fungus group allows us to conclude that the isolate with the greatest capacity to compensate for the negative effect of parasitism, and with the greatest possibility of lasting as a biocon- trol agent is Funneliformis mosseae.Instituto de Fisiología Vegeta

Bioacumulación y respuestas fisiológicas de Festuca arundinacea (Poaceae) al exceso de ZN(II)

There is evidence showing that Festuca arundinacea plants can absorb and accumulate high amounts of Zn(II), greater than those considered as phytotoxic, without affecting plant growth. In order determine the usefulness of this species as a phytoremediation plant, a pot experiment was carried out to measure the physiological strategies employed by F. arundinacea ‘Malma’ Schreb plants growing in environments with an excess of Zn(II). The plants were grown until reaching adequate biomass, when increasing concentrations of Zn(II) were applied. Three months later, growth parameters (total biomass and leaf area), physiological parameters (relative membrane conductivity, chlorophyll and carotene contents, malondialdehyde in roots, and soluble proteins) and Zn(II) content were determined. Total biomass, leaf area, chlorophyll, carotene and protein contents in the aerial part showed a decline with the increase of Zn(II) concentration, whereas the relative conductivity, the protein content and malondialdehyde in roots showed the opposite pattern. Our results suggest that this species can be used for the phytostabilization of polluted soils with moderate concentrations of Zn(II).Existe evidencia que demuestra que las plantas de Festuca arundinacea pueden absorber y acumular altas cantidades de Zn(II), superiores a las consideradas fitotóxicas, sin afectar el crecimiento de las plantas. Para determinar la utilidad de esta especie como planta fitorremediadora, se realizó un experimento en macetas para determinar las estrategias fisiológicas empleadas por F. arundinacea ‘Malma’ Schreb, que crecen en ambientes con exceso de Zn(II) para determinar su utilidad como especie fitorremediadora. Las plantas crecieron hasta alcanzar una biomasa adecuada para la aplicación de tres concentraciones crecientes de Zn(II). Tres meses después se determinaron parámetros de crecimiento (biomasa total y área foliar), parámetros fisiológicos (conductividad relativa de la membrana, contenido de clorofila y carotenos, malondialdehído en raíces y proteínas solubles) y contenido de Zn(II). La biomasa total, área foliar, contenido de clorofila, caroteno y proteínas en la parte aérea mostraron una disminución con el aumento de la concentración de Zn(II), mientras que la conductividad relativa, contenido de proteínas y malondialdehído en las raíces mostraron un patrón opuesto. Nuestros resultados sugieren que esta especie puede ser utilizada para la fitoestabilización de suelos contaminados con concentraciones moderadas de Zn(II).Fil: Gonzalez, Matias Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; ArgentinaFil: Ruscitti, Marcela Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; Argentina. Universidad Nacional del Noroeste de la Provincia de Buenos Aires. Departamento de Ciencias Básicas y Experimentales; ArgentinaFil: Plaza Cazón, Josefina del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; ArgentinaFil: Arango, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; Argentin

Influence of aqueous extracts of Johnson grass rhizomes on mycorrhizal colonization and plant growth of Mentha x piperita L.

El objetivo del presente trabajo fue evaluar el efecto de extractos acuosos de rizomas de Sorghum halepense (sorgo de Alepo) sobre la colonización micorrícica, la viabilidad de las estructuras fúngicas, la biomasa total, la conductividad relativa de las membranas celulares y la fotosíntesis de plantas de Mentha x piperita L. Estacas de menta enraizadas inoculadas y no inoculadas con Glomus intraradices B1 o Glomus mosseae crecieron durante 60 días en una mezcla de perlita:vermiculita:arena tindalizada, regadas con solución de Hoagland y con cuatro concentraciones de extracto acuoso de rizomas de sorgo de Alepo S: 0 %, 5 %, 10 %, 15 %. El experimento fue realizado en invernáculo siguiendo un diseño experimental completamente al azar en un factorial 3 x 4. El mayor nivel de colonización micorrícica se presentó en los tratamientos libres de sorgo de Alepo, 87 % y 92 % para G. mosseae y G. intraradices respectivamente, disminuyendo significativamente con la mayor dosis de extracto. La viabilidad de las estructuras fúngicas también disminuyó significativamente. La dependencia micorrícica aumentó un 35 % con la mayor dosis de extracto. Las mayores concentraciones redujeron significativamente la biomasa total y la fotosíntesis neta, aumentando la conductividad relativa de las membranas de hojas y raíces. Las plantas inoculadas mostraron un mejor comportamiento comparadas con las no inoculadas. Los extractos acuosos de sorgo de Alepo disminuyeron el crecimiento de las plantas mientras que la inoculación con hongos micorrícicos morigeró sus efectos adversos.The aim of this work was to evaluate the effects of aqueous extracts of rhizomes of Sorghum halepense on mycorrhizal colonization, succinate dehydrogenase activity, total dry weight, relative conductivity cell membrane and net photosynthesis in Mentha x piperita plants. Rooted cuttings non inoculated or inoculated with Glomus intraradices or Glomus mosseae grown during 60 days into an inert tyndallized substrate, irrigated with Hoagland solution and four concentrations of aqueous extracts of Johnson grass rhizomes: 0 %, 5 %, 10 % and 15 %. The experiment was carried out in a greenhouse, in 3 x 4 factorial arrangement, in completely randomized design. The higher mycorrhizal colonization occur in treatments without Johnson grass, 87 % and 92 % by G. mosseae y G. intraradices respectively, and decreasing significantly with the higher doses of extract. The fungus structures viability decreasing significantly with the higher doses of extract, and the mycorrhizal dependency increased by 35 % with the highest dose of extract. The higher concentrations of extract reduced the total biomass and photosynthesis, and increase the relative conductivity the membranes of leaves and roots. The inoculated plants showed a better performance than non-inoculated. Aqueous extracts of Johnson grass decreased plant growth while inoculation with mycorrhizal fungi reduces adverse effects.Instituto de Fisiología Vegeta

Micorrizas arbusculares : Biología y aplicaciones en el sector agro-forestal

En la formación de los Ingenieros Agrónomos, Forestales y Biólogos, el conocimiento de la dinámica del suelo es fundamental para la toma de decisiones. La actividad microbiana influye sobre las características físicas, químicas y biológicas del suelo, las cuales determinan la fertilidad de los agroecosistemas. Los hongos formadores de micorrizas arbusculares ejercen un papel fundamental sobre la biología de la planta y la calidad del suelo.Facultad de Ciencias Agrarias y ForestalesFacultad de Ciencias Naturales y Muse

Introducción a la propagación vegetal : De la fisiología a la práctica integrada

La propagación vegetal es una rama de la fisiología vegetal que estudia la reproducción de las plantas, utilizando técnicas y fundamentos adquiridos por la práctica y la investigación. El presente libro comprende conceptos básicos de botánica y fisiología vegetal, que permiten explicar las técnicas de propagación sexual y asexual de distintos grupos vegetales.Facultad de Ciencias Agrarias y Forestale

Micorrização e enxertia melhoram o crescimento de tomateiro e diminuem a população de Nacobbus aberrans

Inoculation with mycorrhizal fungi and the use of rootstock that is tolerant or resistant to nematodes are two strategies that allow the nematode to be controlled, and plants to coexist with the pathogen. However, the two techniques have always been tested in isolation, when their positive effects are less compared to when they are able to act together. In the present work, two rootstocks combined with the mycorrhizal fungus Rhizophagus intraradices were compared, with the aim of evaluating their behaviour on the growth of tomato plants in soils infested with N. aberrans, the false root-knot nematode. The experiment was set up in a completely randomised design with ten replications, in a 3 x 2 x 2 factorial scheme. The treatments consisted of a combination of three factors: a) plant composition: two rootstocks (Solanum lycopersicum var. cerasiform ‘Carolina’ and S. lycopersicum ‘Maxifort’), onto which the ‘Santa Clara’ tomato (S. lycopersicum) was grafted, and a non-grafted plant, considered the control, which was the same cultivar as the graft; b) mycorrhization: mycorrhizal or non-mycorrhizal roots; c) a substrate infested or not infested with N. aberrans. The plants grafted onto ‘Maxifort’ showed significantly greater growth for shoot dry weight, root fresh weight and stem diameter. The rootstock under test had a lower pathogen reproductive factor than did the ungrafted plant. Mycorrhization contributed to a reduction in the number of days until flowering, and a reduction in the final population of N. aberrans for the three plant compositions under test.A inoculação com fungos micorrízicos e o uso de porta-enxertos tolerantes ou resistentes aos nematoides são duas estratégias que permitem o controle e a convivência das plantas com esse patógeno. Contudo, ambas as técnicas sempre foram testadas de forma isolada, sendo seus efeitos positivos menores, se comparados com a possibilidade de suas somatizações. No presente trabalho compararam-se dois porta-enxertos em combinação com o fungo micorrízico Rhizophagus intraradices com o objetivo de avaliar seu comportamento no crescimento de plantas de tomate em solos infestados com N. aberrans, o falso nematoide das galhas. O experimento foi instalado em delineamento interiramente casualizado, com dez repetições, sob um esquema fatorial 3 x 2 x 2. Os tratamentos consistiram na combinação de três fatores: a) as composições de plantas, dois porta-enxertos (Solanum lycopersicum var. cerasiforme cv. ‘Carolina’ e S. lycopersicum cv. ‘Maxifort’), nos quais foram enxertadas S. lycopersicum tomate ‘Santa Clara’; e, a planta pé-franco, considerada controle, que foi a mesma cultivar utilizada como enxerto; b) micorrização: raízes micorrizadas ou não micorrizadas; c) substrato infestado ou não infestado com N. aberrans. Para a massa seca da parte aérea, a massa fresca radicular e o diâmetro do caule as plantas enxertadas em ‘Maxifort’ tiveram um crescimento significativamente maior. Os porta-enxertos testados tiveram fatores de reprodução do patógeno inferiores ao do Pé franco. A micorrização contribuiu para uma diminuição dos dias ate florescimento e uma redução da população final do N. aberrans para as três composições de plantas testadas.Fil: Garita, Sebastián Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; ArgentinaFil: Bernardo, Valeria Fernanda. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; ArgentinaFil: De Almeida Guimarães, Marcelo. Universidade Federal Do Ceara; BrasilFil: Arango, María Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; ArgentinaFil: Ruscitti, Marcela Fabiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; Argentin