Generación de un inoculante acelerador del compostaje / Production of a compost accelerator inoculant

Se realizó el compostaje de una mezcla de estiércol de ovino más paja. Se extrajo inóculo de 5 diferentes fases del proceso de compostaje (a los 18, 23, 28, 33 y 38 días de iniciado) y se evaluó su efecto en la reducción del tiempo de biotransformación de un compost de estiércol de ovino. Las muestras se conservaron en un ultracongelador, después se liofilizaron para obtener el inóculo y se agregaron 50 g a cada tratamiento en la segunda fase experimental. En dicha fase se establecieron seis tratamientos: C = paja (P) + estiércol de ovino (E), T1= P+E +inóculo de 18 días de iniciado el proceso de compostaje (I18), T2= P + E+I23, T3= P + E +128, T4= P + E + I33, T5= P + E + I38, con 3 repeticiones. Estos tratamientos se colocaron en una cámara de ambiente controlado con 45% de humedad relativa y a 30°C. Al mismo tiempo, se colocaron frascos con 50 g de material para medir la producción diaria y la acumulación de CO2, la temperatura, el pH, la conductividad eléctrica, la materia orgánica, el nitrógeno (N), el carbono total, la relación C:N, el tamaño de partícula y la densidad aparente. La producción de CO2 en los tratamientos T2 y T5 mostró diferencia significativa (p < 0,05) de respecto de los demás tratamientos, lo que demuestra que el inóculo de estos tratamientos aceleró la dinámica de los microorganismos y el proceso de compostaje. La calidad y la madurez del compost se garantizan a medida que disminuye la cantidad de CO2.

Composting was performed using a mixture of ovine manure and straw. Inoculum was extracted at five different phases of the composting process (18, 23, 28, 33 and 38 days after the start of the composting process) and its effect on reducing biotransformation time was evaluated in the composted ovine manure. The samples were preserved in a deep freezer, then lyophilized to obtain the inoculum, 50g of which was added to each treatment in the second experimental phase. Six treatments were established; C = straw (P) + ovine manure (E), T1 = P+ E+ inoculum 18 days after the start of the composting process (I18), T2 = P + E + I23, T3 = P + E +128, T4 = P + E +133, T5 = P + E +138, with three replications. Treatments were placed in a controlled-environment chamber at 45% relative humidity and 30°C along with flasks containing 50 g of material to measure daily production, CO2 accumulation, temperature, pH, electric conductivity (dS/m), organic matter (%), total nitrogen (%), total carbon (%), C: N ratio, particle size (Tp) and bulk density (g/l). CO2 production (mg) showed a significant difference (p <.05) of treatments T2 and T5 with respect to the others, which demonstrated that the inoculum of these treatments accelerated the dynamics of microorganisms and the composting process. The quality and maturity of the compost are guaranteed as the amount of CO2 decreases.

[Production of a compost accelerator inoculant]. / Generación de un inoculante acelerador del compostaje.

Composting was performed using a mixture of ovine manure and straw. Inoculum was extracted at five different phases of the composting process (18, 23, 28, 33 and 38 days after the start of the composting process) and its effect on reducing biotransformation time was evaluated in the composted ovine manure. The samples were preserved in a deep freezer, then lyophilized to obtain the inoculum, 50g of which was added to each treatment in the second experimental phase. Six treatments were established; C=straw (P)+ovine manure (E), T1=P+ E+inoculum 18 days after the start of the composting process (I18), T2=P+E+I23, T3=P+E+I28, T4=P+E+I33, T5=P+E+I38, with three replications. Treatments were placed in a controlled-environment chamber at 45% relative humidity and 30°C along with flasks containing 50g of material to measure daily production, CO2 accumulation, temperature, pH, electric conductivity (dS/m), organic matter (%), total nitrogen (%), total carbon (%), C: N ratio, particle size (Tp) and bulk density (g/l). CO2 production (mg) showed a significant difference (p ≤.05) of treatments T2 and T5 with respect to the others, which demonstrated that the inoculum of these treatments accelerated the dynamics of microorganisms and the composting process. The quality and maturity of the compost are guaranteed as the amount of CO2 decreases.

Evaluation of different iron compounds in chlorotic Italian lemon trees (Citrus lemon).

The severe deficiency of iron or ferric chlorosis is a serious problem of most citrus trees established in calcareous soils, as a result of the low availability of iron in these soils and the poor uptake and limited transport of this nutrient in trees. The objective of this study was to evaluate the response of chlorotic Italian lemon trees (Citrus lemon) to the application of iron compounds to roots and stems. On comparing the effects of aqueous solutions of ferric citrate, ferrous sulphate and FeEDDHA chelate, applied to 20% of the roots grown in soil and sand, of trees that were planted in pots containing calcareous soil, it was observed that the chelate fully corrected ferric chlorosis, while citrate and sulphate did not solve the problem. EDDHA induced the root uptake of iron as well as the movement of the nutrient up to the leaves. With the use of injections of ferric solutions into the secondary stem of adult trees, ferric citrate corrected chlorosis but ferrous sulphate did not. The citrate ion expanded the mobility of iron within the plant, from the injection points up to the leaves, whereas the sulphate ion did not sufficiently improve the movement of iron towards the leaf mesophyll.