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El acetoclor es un herbicida ampliamente utilizado en la producción de maíz, cuyo frecuente uso ha provocado persistencia grave en el suelo ocasionando alteraciones en las poblaciones del microbiota, lo que causa bajos rendimientos y dificultad para el establecimiento de otros cultivos, así como también genera amenazas en el ecosistema y en la salud de las personas. Por tal motivo, el propósito de este estudio es aislar e identificar microorganismos bacterianos asociados a los suelos con presencia de acetoclor para abrir un panorama hacia el uso de la biorremediación como biotecnología para la recuperación parcial o total de este recurso. EL proyecto se llevó a cabo dentro de las instalaciones del Instituto de Ciencias Agropecuarias (ICAp), se ubicó un productor de maíz que ha utilizado con frecuencia acetoclor para el control de malezas. Se tomaron muestras de suelo de la parcela y se llevó a cabo el aislamiento de microorganismos por técnica de dilución. Se realizaron lecturas periódicas cada 24 horas de incubación y se aislaron cinco colonias visualmente diferentes para proceder a su purificación. Se llevó a cabo identificación morfológica, la cual la mayoría fueron diferentes en almenos un aspecto, así como pruebas de tinción de Gram en las que resultaron del grupo Grampositivas. Este estudió puede sentar las bases para la identificación de un consorcio bacteriano que pueda tener aplicabilidad biorremediadora en el futuro.

Los suelos agrícolas salinos tienen altas concentraciones de sales solubles (cloruro de sodio), que afectan el crecimiento de cultivos, al disminuir la asimilación de nutrientes y la actividad microbiana. Las plantas pueden ser tolerantes a la salinidad del suelo, pero dependen de algunas propiedades como textura, conductividad eléctrica, pH, entre otros. Este trabajo evaluó un suelo agrícola erosionado por salinidad, mediante parámetros físicos y químicos, para proponer un proceso biológico de recuperación. Los resultados mostraron alto contenido de sodio (2750 ppm), pH de 8.2, conductividad eléctrica de 8.5 dS/m y 19.89 de sodio intercambiable (ESP).Por esta razón, se puede clasificar como un suelo salino-sódico, además los altos valores de pH y conductividad eléctrica infieren baja disponibilidad de algunos micronutrientes, dificultando la absorción de estos a los cultivos. Las características fisicoquímicas del suelo refieren un suelo con baja fertilidad y poca probabilidad para el desarrollo vegetal.

Potable and good-quality drinking water availability is a serious global concern, since several pollution sources significantly contribute to low water quality. Amongst these pollution sources, several are releasing an array of hazardous agents into various environmental and water matrices. Unfortunately, there are not very many ecologically friendly systems available to treat the contaminated environment exclusively. Consequently, heavy metal water contamination leads to many diseases in humans, such as cardiopulmonary diseases and cytotoxicity, among others. To solve this problem, there are a plethora of emerging technologies that play an important role in defining treatment strategies. Phytoremediation, the usage of plants to remove contaminants, is a technology that has been widely used to remediate pollution in soils, with particular reference to toxic elements. Thus, hydroponic systems coupled with bioremediation for the removal of water contaminants have shown great relevance. In this review, we addressed several studies that support the development of phytoremediation systems in water. We cover the importance of applied science and environmental engineering to generate sustainable strategies to improve water quality. In this context, the phytoremediation capabilities of different plant species and possible obstacles that phytoremediation systems may encounter are discussed with suitable examples by comparing different mechanistic processes. According to the presented data, there are a wide range of plant species with water phytoremediation potential that need to be studied from a multidisciplinary perspective to make water phytoremediation a viable method.

The objective of the present study was to examine a biological model under greenhouse conditions for the bioremediation of atrazine contaminated soils. The model consisted in a combination of phytoremediation (using Phaseolus vulgaris L.) and rhizopheric bio-augmentation using native Trichoderma sp., and Rhizobium sp. microorganisms that showed no inhibitory growth at 10,000 mg L−1 of herbicide concentration. 33.3 mg of atrazine 50 g−1 of soil of initial concentration was used and an initial inoculation of 1 × 109 UFC mL−1 of Rhizobium sp. and 1 × 105 conidia mL−1 of Trichoderma sp. were set. Four treatments were arranged: Bean + Trichoderma sp. (B+T); Bean + Rhizobium sp. (BR); Bean + Rhizobium sp. + Trichoderma sp. (B+R+T) and Bean (B). 25.51 mg of atrazine 50 g−1 of soil (76.63%) was removed by the B+T treatment in 40 days (a = 0.050, Tukey). This last indicate that the proposed biological model and methodology developed is useful for atrazine contaminated bioremediation agricultural soils, whi...

The present article reports the isolation and identification of atrazine-tolerant strains of indigenous microorganisms recovered from three representative agricultural sites representing agronomic characteristics of the Tulancingo Valley, Central part of Mexico (disturbed and undisturbed). Biochemical and morphological tests were performed for microorganism’s identification and the minimum inhibitory concentration assay was followed to assess atrazine tolerance. Results showed the microorganism populations varied from 10-5 to 10-6 UFC g-1 of soil for bacteria and 104 - 105 conidia g-1 of soil for fungi. The bacterial genera isolated and identified were: Agrobacterium sp., Bacillus sp., Erwinia sp., Micrococcus sp., Pediococcus sp., Rhizobium sp., Serrantia sp. and Sphingomonas sp. Identified fungal genera were: Alternaria sp., Aspergillus sp., Mucor sp., Cladosporium sp., Penicillium sp., Fusarium sp. and Trichoderma sp. Tests for herbicide tolerance indicate the isolated microorganisms do not show inhibitory growth at 500 to 2,500 ppm of atrazine concentrations under laboratory conditions. The strains of the fungal genera and Rhizobium sp. showed greater tolerance rates to atrazine, based on their growth without inhibition in the presence of 5,000 to 10,000 ppm of the agrochemical. Results suggest the isolated microorganisms may be useful as a viable inoculum for bioremediation purposes in agricultural atrazine-contaminated soils.