In many regions, conservation tillage has been shown to contribute to preserving soil properties. However, in order to promote this practice in new areas, it is necessary to generate information about its results in local environmental conditions. Our objective was to study the effect of No Tillage (NT), Vertical Tillage (VT) and Conventional Tillage (CT) on physical soil properties of a clay loam soil and on yields (Avena sativa L.), in a semiarid area of Mexico. From 2013 to 2016 an experiment was conducted in random blocks, with the three tillage systems as treatments. Four variables were measured; bulk density (Bd), pore space (P), hydraulic conductivity (Ks) and crop yield. Our results did show scarce differences between the tillage systems. Values ranged between 1.21 g cm⁻³ to 1.39 g cm⁻³ for Bd, 45% to 55% for P, and 4.29 mm h⁻¹ to 13.61 mm h⁻¹ for Ks. Although differences were not significant among treatments, Bd decreased 6.7% for CT, 5.6% for NT and 0.7% for VT. P increased 6% for CT, 5% for NT and 0.5% for VT. Ks for CT decreased 6% more than for NT and VT. Average yield was 13% less in NT compared to CT and VT. A long-term investigation is needed in order to determine the effects of tillage methods, in our particular environmental conditions.

Energy used for tillage is an input with a high impact on the cost of crop production; it is desirable to till the soil using minimum energy. The objective of this study was to compare the specific energy expenditure, effect on soil bulk density, and forage yield of maize, by three tillage systems: Disk plow/Disk Harrow/planter (DDP), Chisel plow/Disk harrow/planter (CHDP) and No-Tillage (NT). Energy was measured for tillage operations in the summer season of 2013, 2016, and 2017. Bulk density in 2013 and 2016. Yield in 2013 and 2014. The variables of drawbar force (kN), working speed (m s⁻¹), width (m), depth (m), fuel consumption (L ha⁻¹), bulk density (g cm⁻³), and dry matter yield (Mg ha⁻¹) were measured. Results showed that there were significant differences in the amount of energy used per ha; DDP used an average of 379.75 MJ, CHDP 135.01 MJ, and NT 26.43 MJ. The average energy applied to the soil mass for each system was 400 J kg⁻¹ for DDP, 255.13 J kg⁻¹ for CHDP, and for NT was 237.8 J kg⁻¹. The overall energy efficiency was; 18.23% for DDP, 6.88% for CHDP, and 4.77% for N. The bulk density decreased significantly after three years for NT. There were no significant differences in dry matter yield. In the semiarid condition of Mexico, CHDP and NT are options for saving from 64% to 93% of energy, compared with DDP.

Greenhouse cultivation is highly efficient in the use of water and fertilizers. However, due to intensive production, the greenhouse industry applies ample amounts of water and fertilizers. An alternative to minimize water and nutrient loss is zero-leaching systems, such as closed-loop subirrigation. The objective of the present study was to compare the water and fertilizer use efficiency in containerized tomato plants grown in a subirrigation system and a drip irrigation system. Subirrigated plants exhibited lower biomass than drip-irrigated plants. However, the amount of nutrient solution required to restore evapotranspirated water was lower in subirrigation. The yield was marginally decreased in subirrigated plants compared to drip-irrigated plants. The amount of nutrient solution required to produce 1 kg of fresh tomatoes was 22 L in subirrigation, whereas in drip irrigation, plants demanded 41 L. The total nitrogen applied through the nutrient solution was 75% lower in subirrigation than in drip irrigation, while the phosphorus, potassium, calcium and magnesium applied was 66%, 59%, 70% and 74% lower, respectively. We concluded that the subirrigation system proved to be more water- and nutrient-efficient than the drip irrigation system due to the zero leaching of the nutrient solution, the lower number of irrigation events required and the lower nutrient demand of plants.

Sub-irrigation of greenhouse crops has the potential to increase water and nutrient use efficiency; however, fertilizer salts that are not absorbed by the plants tend to accumulate in the substrate and eventually raise the substrate’s electrical conductivity (EC). The objective of this study was to determine the optimum EC of the nutrient solution in sub-irrigated tomatoes to allow maximum yield. Total fruit yield was higher in sub-irrigated plants with solutions at 2.0 dS m⁻¹ (5105 g per plant), and it was comparable to that obtained for drip-irrigated plants (4903 g per plant); however, the yield of fruits from the second truss was 37% higher in sub-irrigated than in drip-irrigated plants when the EC was 2.0 dS m⁻¹. In contrast, at the end of the growing season, the yield of plants sub-irrigated with nutrient solutions of 2.0 dS m⁻¹ was the lowest, being surpassed by 37% by that of plants treated with 1.4 dS m⁻¹. The dry weight of vegetative plant parts was reduced in sub-irrigated plants, suggesting a shift in dry mass partitioning. Our results show that with sub-irrigation, the growing season should be started using nutrient solutions with higher EC, but eventually, this EC should be decreased to maintain proper substrate EC and high yield.

Las lombrices de tierra son componente esencial de la macrofauna del suelo para mantener su calidad. La labranza puede afectar de forma negativa a sus poblaciones, que normalmente varían con factores ambientales. El objetivo fue evaluar el efecto de tres sistemas de labranza en la población de lombrices de tierra, en presencia de factores temperatura, precipitación y humedad relativa ambientales en dos ciclos de cultivo de maíz forrajero. Se evaluaron la siembra directa (SD), labranza vertical (LV) y labranza convencional (LC), en bloques completos al azar en parcelas de 6 x 40 m con tres repeticiones. Se cuantificaron las lombrices en verano-otoño de 2020 y 2021; antes de la labranza y después de la siembra, control mecánico de malezas y cosecha; LC y LV provocaron la disminución de lombrices mientras que SD promovió un aumento; en especial cuando los factores ambientales generaron las condiciones óptimas para las lombrices.

De los costos de un sistema de producción, las actividades de labranza son de los más altos, pues demandan mucha energía y los combustibles derivados del petróleo incrementan sus precios continuamente. El propósito de este trabajo fue calcular y analizar los costos de dos sistemas de labranza de conservación: labranza vertical y labranza cero, para compararlos con los de la labranza convencional que normalmente se utiliza para producir avena para forraje seco, en la Región Sureste del estado de Coahuila. Para el cálculo de costos, se midió lo siguiente: el uso de combustible por cada una de las labores de los sistemas estudiados, las capacidades de trabajo con cada implemento, el rendimiento del cultivo, el costo del tractor utilizado como fuente de potencia, y el costo de cada uno de los implementos. Con los costos totales de cada sistema de producción y los beneficios de la producción bajo cada sistema, se calculó el índice de beneficiocosto. El mejor beneficio-costo se obtuvo con el sistema de labranza vertical, que tuvo un índice de 2.19, lo que significa que por cada peso invertido en este sistema de producción se obtienen 1.19 pesos de utilidad; luego le siguió el sistema de labranza convencional, con un índice de 2.02, lo que arroja una utilidad de 1.02 pesos por cada peso invertido y, finalmente, con el sistema de cero labranza se logró un índice de 1.98, lo que representa una utilidad de 0.98 pesos por cada peso invertido. En las condiciones del estudio realizado, el mejor sistema en relación con el beneficio-costo fue la labranza vertical, pues tiene una diferencia entre 14% a 17% de mayor beneficio respecto a los otros dos. Los sistemas convencionales y cero labranzas tuvieron un beneficio-costo muy similar entre ellos, pues sólo existió una diferencia de 3% entre ambos.