Juan Manuel Mendoza Almaraz - Academia.edu (original) (raw)
Papers by Juan Manuel Mendoza Almaraz
Agronomía Costarricense, 1969
El queroseno afecta de manera negativa la actividad biológica del suelo, así como el crecimiento ... more El queroseno afecta de manera negativa la actividad biológica del suelo, así como el crecimiento y desarrollo de las plantas. Para analizar lo anterior, se evaluó este contaminante en avena (Avena sativa), cebada (Hordeum vulgare), pasto (Chloris gayana) y trigo (Triticum aestivum), en las poblaciones microbianas de la rizósfera y el rizoplano, así como el porcentaje de degradación del contaminante en suelo rizosférico. Se empleó un diseño experimental completamente al azar con un arreglo factorial 2 x 4, con 8 tratamientos y 5 repeticiones en cada uno. Los factores fueron dosis de queroseno (0 y 2000 mg.kg-1) y especie de planta. A los 56 días de haber establecido el experimento, el suelo contaminado redujo de manera significativa (p≤0,05) el área foliar, la materia seca total y el volumen radical de las 4 gramíneas, con respecto a las establecidas en el suelo sin contaminar. En el suelo contaminado se incrementaron las poblaciones de bacterias totales en el rizoplano y la rizósfer...
Revista Internacional De Contaminacion Ambiental, Aug 17, 2012
Palabras claves: nodulación, HAP, fitotoxicidad, antioxidantes totales, fenólicos, clorofila RESU... more Palabras claves: nodulación, HAP, fitotoxicidad, antioxidantes totales, fenólicos, clorofila RESUMEN Este estudio evaluó el establecimiento de la simbiosis entre Rhizobium tropici CIAT899 y Leucaena leucocephala (Lam.) en sistemas contaminados con naftaleno (NAF) y fenantreno (FEN) y la respuesta de la planta con el contenido de compuestos fenólicos totales (CFT), actividad antioxidante total (AAT) y contenido total de clorofilas (Clo-roT) y carotenos (CaT). A los 31 días, el NAF tuvo efectos negativos en la formación de nódulos, retardando su aparición hasta el día 25 en presencia de 100 mg/L. Ante 20 mg FEN/L, las plantas de L. leucocephala no mostraron diferencias significativas en la formación de nódulos con respecto al testigo, mientras que a 60 y 100 mg FEN/L la nodulación disminuyó significativamente en 52 %. La inoculación con R. tropici incrementó el peso seco total (PST) hasta en 150 % comparado con las plantas no inoculadas. El CFT en hoja fue significativamente mayor en los tratamientos no inoculados en comparación con aquellos inoculados con R. tropici y significativamente mayor ante FEN que con NAF. Para ambos contaminantes, la concentración de 100 mg/L produjo mayor CFT y AAT en comparación con 20 y 60 mg/L. Para el caso de raíz, los tratamientos sin contaminantes en ausencia de R. tropici presentaron mayor CFT y AAT. Para los nódulos, la AAT incrementó significativamente ante NAF, mientras que ante FEN disminuyó. El NAF o el FEN redujeron significativamente el contenido de CloroT, el cual fue significativamente mayor en plantas con Rhizobium en comparación con las plantas no inoculadas. El contenido de CaT en plantas no inoculadas incrementó en presencia de NAF y FEN.
Soil Science Society of America Journal, 2009
Applied Soil Ecology, 2014
This study identified microbial functional groups like total culturable bacteria, potential N 2-f... more This study identified microbial functional groups like total culturable bacteria, potential N 2-fixing free living bacteria, N 2-fixing hydrocarbonoclastic bacteria, N-assimilating hydrocarbonoclastic bacteria, total fungi, actinobacteria, P-solubilizers, lipolytic microorganisms, and starch, cellulose, pectin and protein degrading microorganisms, isolated from the rhizosphere of four species of mangroves (Red, Black, White, and Button) from the natural protected area at the Terminos Lagoon, Campeche, México. Overall, microbial populations showed significant differences (P < 0.05) among the four mangrove species. The rhizosphere of White mangrove showed better chemical and textural soil properties, and harbored the highest microbial populations when compared to the remaining mangrove species. The principal component analysis indicated that two components accounted the 85.3% of the total variation. The most significant textural and chemical soil properties were the major components, CP1 (organic matter and total organic carbon) and CP2 (sand and clay). Microbial populations correlated (P < 0.05, Pearson coefficient) with sand and clay particles, and with some soil chemical properties such as organic matter. The total nitrogen and organic carbon significantly correlated with cellulose degraders, while phosphorus with N 2-fixing bacteria, total fungi, and with pectin and starch degraders.
Journal of Environmental Management, 2012
Petroleum hydrocarbons (PHs) are major organic contaminants in soils, whose degradation process i... more Petroleum hydrocarbons (PHs) are major organic contaminants in soils, whose degradation process is mediated by microorganisms such as the filamentous fungi Cunninghamella elegans and Phanerochaete chrysosporium. However, little is known about the tolerance and the degradation capability of Trichoderma species when exposed to PH. This research evaluated the tolerance and growth of 11 Trichoderma strains to crude oil (COil), naphthalene (NAPH), phenanthrene (PHE) and benzo[a]pyrene (B[a]P) by using in vitro systems. Petri dishes containing solid mineral minimum medium were separately contaminated with COil, with seven doses of either NAPH or PHE (250, 500, 750, 1000, 2000, and 3000 mg L(-1)), and with six doses of B[a]P (10, 25, 50, 75, and 100 mg L(-1)). Non-contaminated plates were used as controls. Trichoderma strains were exposed to all the contaminants by triplicate, and the growth of each fungal colony was daily recorded. No significant differences were observed among Trichoderma strains when they were exposed to COil in which the maximum fungal growth was reached at 96 h. In contrast, Trichoderma strains showed variations to tolerate and grow under different doses of either NAPH, PHE or B[a]P. Increasing NAPH doses resulted on significant greater fungal growth inhibition than PHE doses. The exposure to B[a]P did not inhibited growth of some Trichoderma strains.
Acta Agriculturae Scandinavica, Section B - Soil & Plant Science, 2011
A field experiment was conducted at Ste. Anne de Bellevue, Quebec during the growing seasons of 2... more A field experiment was conducted at Ste. Anne de Bellevue, Quebec during the growing seasons of 2002 and 2003, to study the effect of Nod factor treatments, applied at specific growth stages, on photosynthesis and biomass accumulation by soybean grown under two tillage systems (conventional tillage, no-tillage). Spray application of Nod factors increased photosynthesis at the four fully expanded trifoliate
Canadian Journal of Plant Pathology, 2004
Crop production and climate change affect each other because crop production (1) produces greenho... more Crop production and climate change affect each other because crop production (1) produces greenhouse gases (GHGs), (2) is affected by climate change, (3) will have to adapt to changed climatic regimes, and (4) has a potential role in mitigating the production of GHGs. Agriculture is not a major producer of GHGs, at less than 10% of Canada's total. Agriculture is a major producer of methane and nitrous oxide (21 and 310 times more effective at heat trapping than CO 2 , respectively), but a minor producer of CO 2. The impacts on agriculture will come through increased CO 2 effects on plant growth, warmer and drier conditions, changes in wind speed, insect and disease pressures, and many more subtle changes resulting from altered interactions among components of crop agro-ecosystems. Predictions are for net increases in world food production as temperature increases become larger. Potential adaptations are (1) management and genetic alterations to crops, (2) legislative changes, (3) policy and economic changes, and (4) adoption of mitigation practices. Mitigation of GHG effects can be through new cropping systems and crops that reduce net GHG production by emitting less nitrous oxide, increasing soil organic matter content, and allowing production of bio-products such as bio-fuels.
Agronomía Costarricense, 1969
El queroseno afecta de manera negativa la actividad biológica del suelo, así como el crecimiento ... more El queroseno afecta de manera negativa la actividad biológica del suelo, así como el crecimiento y desarrollo de las plantas. Para analizar lo anterior, se evaluó este contaminante en avena (Avena sativa), cebada (Hordeum vulgare), pasto (Chloris gayana) y trigo (Triticum aestivum), en las poblaciones microbianas de la rizósfera y el rizoplano, así como el porcentaje de degradación del contaminante en suelo rizosférico. Se empleó un diseño experimental completamente al azar con un arreglo factorial 2 x 4, con 8 tratamientos y 5 repeticiones en cada uno. Los factores fueron dosis de queroseno (0 y 2000 mg.kg-1) y especie de planta. A los 56 días de haber establecido el experimento, el suelo contaminado redujo de manera significativa (p≤0,05) el área foliar, la materia seca total y el volumen radical de las 4 gramíneas, con respecto a las establecidas en el suelo sin contaminar. En el suelo contaminado se incrementaron las poblaciones de bacterias totales en el rizoplano y la rizósfer...
Revista Internacional De Contaminacion Ambiental, Aug 17, 2012
Palabras claves: nodulación, HAP, fitotoxicidad, antioxidantes totales, fenólicos, clorofila RESU... more Palabras claves: nodulación, HAP, fitotoxicidad, antioxidantes totales, fenólicos, clorofila RESUMEN Este estudio evaluó el establecimiento de la simbiosis entre Rhizobium tropici CIAT899 y Leucaena leucocephala (Lam.) en sistemas contaminados con naftaleno (NAF) y fenantreno (FEN) y la respuesta de la planta con el contenido de compuestos fenólicos totales (CFT), actividad antioxidante total (AAT) y contenido total de clorofilas (Clo-roT) y carotenos (CaT). A los 31 días, el NAF tuvo efectos negativos en la formación de nódulos, retardando su aparición hasta el día 25 en presencia de 100 mg/L. Ante 20 mg FEN/L, las plantas de L. leucocephala no mostraron diferencias significativas en la formación de nódulos con respecto al testigo, mientras que a 60 y 100 mg FEN/L la nodulación disminuyó significativamente en 52 %. La inoculación con R. tropici incrementó el peso seco total (PST) hasta en 150 % comparado con las plantas no inoculadas. El CFT en hoja fue significativamente mayor en los tratamientos no inoculados en comparación con aquellos inoculados con R. tropici y significativamente mayor ante FEN que con NAF. Para ambos contaminantes, la concentración de 100 mg/L produjo mayor CFT y AAT en comparación con 20 y 60 mg/L. Para el caso de raíz, los tratamientos sin contaminantes en ausencia de R. tropici presentaron mayor CFT y AAT. Para los nódulos, la AAT incrementó significativamente ante NAF, mientras que ante FEN disminuyó. El NAF o el FEN redujeron significativamente el contenido de CloroT, el cual fue significativamente mayor en plantas con Rhizobium en comparación con las plantas no inoculadas. El contenido de CaT en plantas no inoculadas incrementó en presencia de NAF y FEN.
Soil Science Society of America Journal, 2009
Applied Soil Ecology, 2014
This study identified microbial functional groups like total culturable bacteria, potential N 2-f... more This study identified microbial functional groups like total culturable bacteria, potential N 2-fixing free living bacteria, N 2-fixing hydrocarbonoclastic bacteria, N-assimilating hydrocarbonoclastic bacteria, total fungi, actinobacteria, P-solubilizers, lipolytic microorganisms, and starch, cellulose, pectin and protein degrading microorganisms, isolated from the rhizosphere of four species of mangroves (Red, Black, White, and Button) from the natural protected area at the Terminos Lagoon, Campeche, México. Overall, microbial populations showed significant differences (P < 0.05) among the four mangrove species. The rhizosphere of White mangrove showed better chemical and textural soil properties, and harbored the highest microbial populations when compared to the remaining mangrove species. The principal component analysis indicated that two components accounted the 85.3% of the total variation. The most significant textural and chemical soil properties were the major components, CP1 (organic matter and total organic carbon) and CP2 (sand and clay). Microbial populations correlated (P < 0.05, Pearson coefficient) with sand and clay particles, and with some soil chemical properties such as organic matter. The total nitrogen and organic carbon significantly correlated with cellulose degraders, while phosphorus with N 2-fixing bacteria, total fungi, and with pectin and starch degraders.
Journal of Environmental Management, 2012
Petroleum hydrocarbons (PHs) are major organic contaminants in soils, whose degradation process i... more Petroleum hydrocarbons (PHs) are major organic contaminants in soils, whose degradation process is mediated by microorganisms such as the filamentous fungi Cunninghamella elegans and Phanerochaete chrysosporium. However, little is known about the tolerance and the degradation capability of Trichoderma species when exposed to PH. This research evaluated the tolerance and growth of 11 Trichoderma strains to crude oil (COil), naphthalene (NAPH), phenanthrene (PHE) and benzo[a]pyrene (B[a]P) by using in vitro systems. Petri dishes containing solid mineral minimum medium were separately contaminated with COil, with seven doses of either NAPH or PHE (250, 500, 750, 1000, 2000, and 3000 mg L(-1)), and with six doses of B[a]P (10, 25, 50, 75, and 100 mg L(-1)). Non-contaminated plates were used as controls. Trichoderma strains were exposed to all the contaminants by triplicate, and the growth of each fungal colony was daily recorded. No significant differences were observed among Trichoderma strains when they were exposed to COil in which the maximum fungal growth was reached at 96 h. In contrast, Trichoderma strains showed variations to tolerate and grow under different doses of either NAPH, PHE or B[a]P. Increasing NAPH doses resulted on significant greater fungal growth inhibition than PHE doses. The exposure to B[a]P did not inhibited growth of some Trichoderma strains.
Acta Agriculturae Scandinavica, Section B - Soil & Plant Science, 2011
A field experiment was conducted at Ste. Anne de Bellevue, Quebec during the growing seasons of 2... more A field experiment was conducted at Ste. Anne de Bellevue, Quebec during the growing seasons of 2002 and 2003, to study the effect of Nod factor treatments, applied at specific growth stages, on photosynthesis and biomass accumulation by soybean grown under two tillage systems (conventional tillage, no-tillage). Spray application of Nod factors increased photosynthesis at the four fully expanded trifoliate
Canadian Journal of Plant Pathology, 2004
Crop production and climate change affect each other because crop production (1) produces greenho... more Crop production and climate change affect each other because crop production (1) produces greenhouse gases (GHGs), (2) is affected by climate change, (3) will have to adapt to changed climatic regimes, and (4) has a potential role in mitigating the production of GHGs. Agriculture is not a major producer of GHGs, at less than 10% of Canada's total. Agriculture is a major producer of methane and nitrous oxide (21 and 310 times more effective at heat trapping than CO 2 , respectively), but a minor producer of CO 2. The impacts on agriculture will come through increased CO 2 effects on plant growth, warmer and drier conditions, changes in wind speed, insect and disease pressures, and many more subtle changes resulting from altered interactions among components of crop agro-ecosystems. Predictions are for net increases in world food production as temperature increases become larger. Potential adaptations are (1) management and genetic alterations to crops, (2) legislative changes, (3) policy and economic changes, and (4) adoption of mitigation practices. Mitigation of GHG effects can be through new cropping systems and crops that reduce net GHG production by emitting less nitrous oxide, increasing soil organic matter content, and allowing production of bio-products such as bio-fuels.