ABSTRACT
Resumen Objetivo. Identificar microorganismos fitopatógenos presentes en las aguas utilizadas para riego en la cuenca media del rio Bogotá. Métodos. Las muestras fueron tomadas en doce fincas de la cuenca media y analizadas con la técnica de filtración por membrana. Las bacterias se identificaron por bioquímica y los hongos por claves dicotomas. Resultados. El agua de riego analizada contenía bacterias como: E.coli, P. vulgaris, A. urinae, E. cloacae, B.cereus, S. marcescens, B. brevis, y en cuanto a los hongos se encontraron: Aspergillus fumigatus, Aspergillus flavus., Mucor sp., Rhizopus sp., Penicillium sp. y Fusarium sp. La presencia de estos potenciales fitopatógenos en el agua indican un alto riesgo de contaminación y dispersión de éstos en los cultivos.
Abstract Objective. Identify phytopathogenic microorganisms present in the water used for irrigation in the middle basin of the river Bogota. Methods. Samples were taken at 12 farms of the middle basin and analyzed by the membrane filtration technique. The bacteria were identified by biochemical and fungi by dichotomies keys. Results. The irrigation water contained bacteria analyzed as E. coli, P. vulgaris, A. urinae, E. cloacae, B. cereus, S. marcescens, B. brevis, and as for the mushrooms found: A. fumigatus, A. flavus, Mucor sp., Rhizopus sp., Penicillium sp. and Fusarium sp. The presence of these potential pathogens in water indicate a high risk of contamination and dispersion thereof in crops.
Subject(s)
Humans , Agricultural Irrigation , Wastewater Pumps , Hydrographic Basins , Aquatic MicroorganismsABSTRACT
Abstract The water resources mismanagement is a common concern in the agriculture, and this issue is boosting salinity processes in the Colombian lands. Thus, this paper aimed to assess the soil salinity risk in the RUT irrigation district for sugarcane, grape, and passion fruit by coupling SOSALRIEGO-GIS. First, sources of surface water and their influence areas were identified in the RUT irrigation district. Afterwards, inputs (water ionic constituents, electrical conductivity of rainwater, annual rainfall, crop salt tolerance, soil texture, and leaching fraction) fed in the SOSALRIEGO model, and then, the leaching requirement (LR) of each zone was computed (output) for each crop. Finally, employing GIS, LR values were arranged in categories in order to map the soil salinity risk in the RUT irrigation district for each crop and zone. The soil salinity risk fell into a medium rank for sugarcane, medium to high ranks for grape, and high to very high ranks for passion fruit. Furthermore, the soil salinity risk was higher in zones with poor irrigation water quality. Zones II and III, which canals convey domestic wastewater and drained water fell in greater salinity risk category than zone I, which bears water withdrawal from the Cauca River.
Resumen La inadecuada gestión de los recursos hídricos es una preocupación común en la agricultura, y este hecho está impulsando procesos de salinización en los suelos de Colombia. Por lo tanto, este trabajo tuvo como objetivo evaluar el riesgo de salinización del suelo en el distrito de riego RUT para cultivos de caña de azúcar, uva, maracuyá integrando el modelo SOSALRIEGO con SIG. En primer lugar, se identificaron las fuentes hídricas y sus áreas de influencia. Posteriormente, los parámetros de entrada (composición iónica del agua, conductividad eléctrica del agua de lluvia, precipitación anual, tolerancia de cultivos a la salinidad, cultivos, textura del suelo y la eficiencia de lavado) alimentaron el modelo SOSALRIEGO y, a continuación, el Requerimiento de Lavado de sales (RL) fue calculado para cada cultivo. Por último, utilizando SIG, los valores RL se organizaron en categorías con el fin de mapear el riesgo de salinización del suelo en el distrito de riego RUT para cada cultivo en cada zona. El riesgo de salinización se clasificó como medio para caña de azúcar, medio a Alto para la uva, y alto a muy alto para maracuyá. Además, el riesgo salinización del suelo encontrado fue mayor en zonas con baja calidad del agua de riego. Las Zonas II y III, en las cuales los canales conducen aguas residuales domésticas y el agua drenada fueron calificados en categorías superiores de riesgo de salinización que la Zona I, la cual recibe agua extraída directamente del río Cauca.
Resumo A inadequada gestão dos recursos hídricos é uma preocupação comum na agricultura, este fato está impulsando processos de salinização nos solos da Colômbia. Portanto, esta pesquisa objetivou avaliar o risco da salinização dos solos no distrito de irrigação RUT às culturas de cana-de-açúcar, uva e maracujá; integrando o modelo SOSALRIEGO com os Sistemas de Informações Geográficas (SIG). Em primeiro lugar, os parâmetros de entrada (composição iônica da água de irrigação, condutividade elétrica da água de precipitação, precipitação anual, tolerância das culturas à salinidade, culturas, textura do solo e eficiência de lavado de sais) alimentaram o modelo SOSALRIEGO e, seguidamente o requerimento de lavado de sais (RL) foi calculado. Finalmente, usando os SIG, os valores de RL foram categorizados com o objetivo de mapear o risco de salinização dos solos na área de estudo para cada cultura em cada zona. O risco de salinização foi classificado como Médio para a cultura da cana-de-açúcar, Médio a Elevado para a cultura da uva, e Elevado a Muito Elevado para o maracujá. Além disso, o risco de salinização foi maior nas zonas com menor qualidade da água de irrigação. As zonas II e III, cujos canais conduzem águas residuais e de drenagem foram qualificados em categorias maiores de risco do que a zona I, a qual extrai a água diretamente do Rio Cauca.
ABSTRACT
Se describe y descubre el nivel de importancia que los agricultores de León, Guanajuato, México atribuyen a los factores productivos capacitación, producción, costos, apoyos gubernamentales y tecnología, relacionados con la actividad de la producción agrícola en sus parcelas. Es decir, se conoce la realidad de los agricultores para que posteriormenteel gobierno, las instituciones de educación y asociaciones agrícolas, colaboren entre sí de manera coordinada en beneficio de dicha actividad agrícola.
The level of importance of the farmers in Leon, Guanajuato, Mexico is discovered and described, which is attributed to production factors, training, production, costs, governmentsupport, and technology, related to the activity of agricultural production in their plots. That is to say, the reality of the farmers is known so that later, the government, educational institutions, and agricultural associations, cooperate with each other in a coordinatedmanner for the benefit of the agricultural activity.
Subject(s)
Crop Production , Agriculture , Efficiency , Mexico , Rural Population , Rural WorkersABSTRACT
Resumo Este estudo objetivou avaliar a qualidade física, química e microbiológica das águas utilizadas para irrigação de hortaliças na Bacia do Córrego Sujo, Teresópolis, RJ, importante polo agrícola cuja produção abastece a região metropolitana do Rio de Janeiro. Análises de coliformes termotolerantes, bactérias heterotróficas totais e parâmetros físico-químicos foram realizados em oito diferentes pontos dos canais fluviais dessa bacia. Segundo a Resolução CONAMA 357/2005, os resultados dos parâmetros físico-químicos estudados, exceção para oxigênio dissolvido em duas estações (6 e 7), apresentaram valores próprios para a irrigação de hortaliças consumidas cruas e que se desenvolvem rente ao solo, como as cultivadas no local. Porém, segundo a mesma resolução, apenas uma estação (4) apresentou água com qualidade microbiológica própria para esse mesmo fim. Nossos resultados apontam para a necessidade de um maior controle da qualidade das águas utilizadas para irrigação nessa região; uma vez que hortaliças irrigadas com águas contaminadas podem transmitir diversas doenças.
Abstract This study aimed to evaluate the physical, chemical and microbiological quality of the water used for vegetables irrigation in the Córrego Sujo basin, Teresopolis-RJ; an important agricultural pole that supplies the metropolitan region of Rio de Janeiro. Analysis of fecal coliforms, total heterotrophic bacteria and physicochemical parameters were held in eight different points of the river channels in this basin. According to the CONAMA Resolution 357/2005, physicochemical parameters results, except for dissolved oxygen, in two stations (6 and 7) showed proper values for irrigation of raw consumed vegetables and low vegetation like those cultivated in the region. However, according to the same resolution, only one station (4) presented water with proper microbiological quality for the same purpose. Our results indicate the need for greater quality control of the water used for irrigation in this region as vegetables irrigation with contaminated water can transmit several diseases.
ABSTRACT
A study was carried out to determine the water requirement of main crops in the perumal tank irrigation command area in Cuddalore district. The main crops include rice, groundnut, and sugarcane. The crop water requirements were determined using 15 year climatic data using CROPWAT 8.0. The seven crop growth stages (nursery,nursery/land preparation,land prepearation,initial,development,mid season,late season) and three decades (I,II,III) were considered for all crops. Crops were planted during 2012 kuruvai season and the crop coefficient was determined for each crop. Reference Crop Evapotranspiration (ETo) was determined using the FAO Penman Monteith method and the effective rainfall was calculated using USDA S.C. Method. The study shows that for the study area, reference evapotranspiration (ETo) varied from 3.67 to 6.42 mm/day and the effective rainfall varied from 12.8 to 166.8 mm. Crop evapotranspiration (ETo) and the crop water requirement for Rice varied from 0.74 mm/day to 6.23 mm/day and 0.0 mm/dec to 244 mm/dec, for groundnut 2.4 mm/day to 5.03 mm/day and 0.0 mm/dec to 29.2 mm/dec, for Rice (Navarai) 0.45 mm/day to 6.49 mm/day and 0.0 mm/dec to 152.5 mm/dec, for Groundnut (Navarai) 1.78 mm/day to 5.79 mm/day and 4.1 mm/dec to 54.8 mm/dec and for Sugarcane 2.07 mm/day to 6.57 mm/day and 0.0 mm/dec to 63.9 mm/dec respectively. The peak water requirement was 1.11 l/s/ha or 9.6 mm/day with an application efficiency of 70%.
ABSTRACT
Tobacco mosaic virus (TMV) causes significant yield loss in susceptible crops irrigated with contaminated water. However, detection of TMV in water is difficult owing to extremely low concentrations of the virus. Here, we developed a simple method for the detection and quantiifcation of TMV in irrigation water. TMV was reliably detected at concentrations as low as 10 viral copies/μL with real-time PCR. The sensitivity of detection was further improved using polyethylene glycol 6000 (PEG6000, MW 6000) to concentrate TMV from water samples. Among the 28 samples from Shaanxi Province examined with our method, 17 were tested positive after virus concentration. Infectivity of TMV in the original water sample as well as after concentration was conifrmed using PCR. The limiting concentration of TMV in water to re-infect plants was determined as 102 viral copies/mL. The method developed in this study offers a novel approach to detect TMV in irrigation water, and may provide an effective tool to control crop infection.