El objetivo del presente estudio fue analizar la calidad del agua para riego y suelos agrícolas del municipio de Tuxcacuesco. Se realizaron muestreos compuestos de ambos recursos durante Junio de 2015, las colectas se analizaron en el laboratorio de suelos del CUCSUR, se estimaron pH, CE, Ca2+, Mg2+, Na, K, CHO3(2+), HCO3, SO4(2-) y Cl; los índices de salinidad, sodicidad, toxicidad, así como concentración iónica, contenido de Boro y fertilidad del suelo. Los valores de pH en suelo y agua se presentaron en un rango de 7.1 a 8.5, respecto a la concentración iónica se clasificó a las aguas cómo magnésicas-bicarbonatadas y a las soluciones de suelo como sódicas-bicarbonatadas, en cuanto a RAS y CE ambos recursos fueron clasificados como S1 y C1 lo que significa que sus contenidos de sales y sodio son bajos, en el caso particular de fertilidad del suelo, los nutrientes principales (N, P, K y materia orgánica) se encuentran bajos respecto a los reportados en otras investigaciones. Los valores de CSR para las muestras tanto de agua como de suelo se encuentran entre -12 y -1.3. El contenido de Boro no alcanza los niveles de toxicidad, por el contrario, representa un aporte como micronutriente para los cultivos. En conjunto ambos recursos son recomendables para las actividades agrícolas, sin embargo en el caso puntual de fertilidad del suelo, es necesario modificar algunas prácticas para elevar las concentraciones de N, P, K y materia orgánica, con el fin de incrementar la fertilidad y fomentar el manejo sostenible del recurso. | The aim of this study was to analyze the quality of water for irrigation and agricultural soils in the municipality of Tuxcacuesco. Sampling compounds of both resources were made during June 2015, the collects were analyzed in the soil laboratory of CUCSUR were estimated pH; CE, Ca2+, Mg2+, Na, K, CHO3(2+), HCO3, SO4(2-) and Cl, salinity levels, sodicity, toxicity and ionic strength, Boron content and soil fertility. The pH values in soil and water were presented in a range of 7.1 to 8.5, respect to the ionic con-centration water was ranked as magnesium-bicarbonate and soil solutions as sodium-bicarbonate, regarding RAS and EC both resources were classified as C1 and S1 which means that their percentage of salts and sodium are low, in the case of soil fertility, the content of the primary nutrients (N, P, K and organic matter) are low compared to reported in other investigations. SRC values for samples of both water and soil are between -12 and -1.3. The Boron content does not reach toxic levels, by contrast, it represents a contribution of this micronutrient for crops. Together, both resources are recommended for agricultural activities, however, in the specific case of soil fertility, it is necessary to change some practices to increase the concentrations of N, P, K and organic matter, in order to increase fertility and promote sustainable resource management.

Amaranth (Amaranthus hypochondriacus L.), which is considered an alternative source of vegetable protein, is grown particularly under rainfed conditions. Therefore, it is important to look for better management practices that lead to a more efficient use of resources, such as water and essential nutriments, to obtain higher yields. The aim of this work was to determine the influence of nitrogen and plant density on phenology, nitrogen and water use efficiency (WUE), biomass production, and seed yield of amaranth planted on June 11, 1999, with 0, 10, and 20 g m(-2) N and 12.5, 25.0, and 33.3 plants m(-2). With the application of N and with a higher plant density (PD), the efficiency in water use and in N was greater, and in consequence, biomass production and yield increased as well. These increments were higher with higher N level and higher DP. In this way, with 20 g N m(-2) and 33.3 plant m(-2) a biomass production of 2827 g m(-2) and seed yield of 346 g m(-2) were obtained. Phenology was not affected by the treatments. The requirement of sowing heat units to physiological maturity was 1629 UC and 385 mm of water used in evapotranspiration.

Editado por Johann Gnadlinger, Everaldo Rocha Porto, Eduardo Assis Menezes, Paulo Roberto Coelho Lopes, Ines Rieder. | O efeito de fertilizantes orgânicos e químicos aplicados em fundação, associado a técnicas de captação de água de chuva ?in situ? foi avaliado na cultura do milho em condições de sequeiro. Foram utilizados dois sistemas de captação de água de chuva ?in situ?, um conhecido como sistema W e o outro como Guimarães Duque. Os tratamentos avaliados foram: 1.Testemunha (sem fertilizantes químicos e orgânicos); 2. Sistema de captação mais esterco bovino; 3. Sistema de captação mais fósforo; 4. Sistema de captação mais composto orgânico, e 5. Sistema de captação mais esterco bovino mais fósforo. Observou-se a mesma tendência de produtividade em todos os tratamentos com os dois sistemas de captação de água. O tratamento 5 apresentou a maior produtividade de milho, seguido dos tratamentos 4, 3, 2 e 1 (testemunha), respectivamente. Todos os tratamentos no sistema W apresentaram maior produtividade que no sistema Guimarães Duque, indicando uma maior eficiência do primeiro sistema no armazenamento de água no solo.