Relative Forage Yield of Intercropped Lucerne (\u3ci\u3eMedicago sativa\u3c/i\u3e L.) And Winter Forage Cereals

In tropical regions of the world intercropping is mainly associated with the production of maize for grain, while in temperate areas it is associated with the efficient production of forage. There is increasing interest in the development of cereal - legume intercropping in some temperate regions (reviewed by Mason & Pritchard, 1987). The aim of this study was to compare the relative forage yield of intercropped lucerne and cereal

Tillage Systems in the Establishment of Pastures in Argentinian Subhumid Area

The effect of three tillage systems on the number of plants produced and forage production of a pasture the first year of establishment was assessed in this experiment. The components of the pasture were alfalfa (Medicago sativa L.), tall fescue (Festuca arundinacea Shreb), orchard grass (Dactilys glomerata L), and prairie grass (Bromus unioloides). Treatments were three tillage systems: conventional tillage (CT), reduced tillage (RT), and direct sowing (DS). Sowing was performed with (NI) and without fertilizers (N0) in each treatment. A split-plot experimental design with two repetitions was used, with tillage being the main factor and the fertilization levels the secondary one. Results were subjected to ANOVA while means were compared by the Duncan Test Counts. These were conducted 90 days after sowing to determine the number of emerged alfalfa and grass seedlings. In November, before starting direct grazing, hand cut samples were taken to determine total biomass and also biomass production of each component of the pasture. Total stand plant and grass stand, was significantly affected (P \u3c 0.05) by the tillage factor. Forage production of both alfalfa and grass, and total production was higher with conventional tillage (CT) and differed significantly (P \u3c 0.05) from direct sowing (DS). The fertilizing effect and its interaction with the tillage factor was not statistically significant (P \u3c 0.05) for any of the components measured. Results indicate that direct sowing seems to condition grass plant stand and forage production of each of the pasture components in the year of establishment

Biomass Vertical Distribution in a Grazed Grassland Under Monoespecific and Mixed Grazing

Mixed grazing is defined as the use of the same forage resource for more than one herbivore species. It has been shown that different herbivore species have specific grazing modalities (Black and Kenney, 1984), which may differentially modify the structure of the pasture. The aim of this study was to evaluate the biomass vertical distribution in a sward with mixed grazing

Effects of Tree and Tillage Systems on the Productivity of the Herbaceous Stratum in Silvopastoral Systems in the Southwest of Córdoba, Argentina

In the southwest of Córdoba, Argentina, there are lands with severe water erosion, due to the interaction of rolling pampas, high intensity precipitation, loam soil, and farming systems based on annual crops (Cantero et al., 1998). In an attempt to mitigate the erosive processes, a silvopastoral system was established in which winter forage was combined with trees. To improve the physical condition of the soil, two tillage systems were implemented. The objective of this paper was to determine the effect of trees and tillage systems on the production of forage

Efecto de la Defoliaci\uf3n Sobre la Din\ue1mica del Crecimiento de Triticale

Using Triticale (xTriticosecale Wittmack) forage, the effects of time of utilization and stocking rate on growth dynamics were studied. Cv. 'Qui\uf1\ue9-UNRC' was employed after grazing in vegetative (EV) and reproductive stages (ER) using three stocking rates C1=2, C2=3 and C3=5 steers ha-1. The experimental design was a randomized complete block with a factorial arrangement. At the beginning, the biomass, leaf area index (IAF), tiller number and height of plants were measured. During re-growths, the rates of leaf appearance (TAH), elongation (TEH), tiller density and accumulated biomass were determined. Later, mean leaf lifespan (VMF), growth rate (TCC), and senescence (TSC) were calculated. At the initial stage, C1 had higher biomass, foliar area and plant height than C3 (p=0.05). In the re-growths, the average TAH was 17.4 days in EV grazing and 25 days in ER (p 64 0.001). There was a VMF interaction (p 64 0.05); C2 had the lowest value in EV (46.6 days) and ER the highest (140 days). The TCC decreased from 23 to 21.9 and 15.1 kg DM ha-1d-1 for C1, C2 and C3, respectively (p 64 0.001) on increasing the animal load. The TSC with EV and ER grazing was 5.44 y 2.83 kg DM ha-1d-1 (p 64 0.05) respectively. The accumulated biomass was higher with low stocking rates(p 64 0.05) reaching a value of 4275.8 kg DM ha-1.En triticale (xTriticosecale Wittmack) forrajero se estudiaron los efectos del momento de utilizaci\uf3n y la carga animal sobre la din\ue1mica del crecimiento. Se emple\uf3 el cv. 'Qui\uf1\ue9-UNRC' pastoreado en estado vegetativo (EV) y reproductivo (ER) con tres niveles de carga animal: C1 = 2, C2 = 3 y C3 = 5 novillos ha-1. El dise\uf1o estad\uedstico fue bloques completos al azar con arreglo factorial. Al inicio se determin\uf3 biomasa, \ue1rea foliar, n\ufamero de macollos y altura de plantas. En los rebrotes se analizaron las tasas de aparici\uf3n y elongaci\uf3n de hojas, densidad de macollos y biomasa acumulada. Luego se calcul\uf3 la vida media foliar (VMF) y las tasas de crecimiento (TCC) y senescencia del cultivo (TSC). En la situaci\uf3n inicial, C1 present\uf3 mayor biomasa, \ue1rea foliar y altura de plantas que C3 (p 64 0,05). En los rebrotes, la tasa de aparici\uf3n de hojas (TAH) promedio fue de 17,4 d\uedas con pastoreo en EV y 25 d\uedas en ER (p 64 0,001). En la VMF hubo interacci\uf3n (p 64 0,05); C2 present\uf3 el menor valor (46,6 d\uedas) en EV y el mayor en ER (140 d\uedas). La TCC disminuy\uf3 de 23 a 21,9 y 15,1 kg MS ha-1 d-1 al aumentar la carga animal (p 64 0,001). La TSC con pastoreo en EV y ER fue 5,44 y 2,83 kg MS ha-1 d-1, respectivamente (p 64 0,05). La biomasa acumulada fue mayor en las cargas bajas (p 64 0,05), llegando a valores de 4275,8 kg MS ha-1

PF 13. Effect of grazing density on harvest efficiency, forage allotment and meat production of a triticale crop

In the FAV UNRC, Experimental farm, grazing density effect on the productivity of a triticale crop (xTriticosecale Witmack) CV Quiñe UNRC was evaluate, seeding at 28-03-96. Experimental units of 1.5; 1.0; 0.75 and 0.6 ha were used giving four treatments C1: 2 an./ha, C2: 3 an./ha, C3: 4 an./ha and C4: 5an./ha A rotational grazing system was established mode of 7 days of harvest and 40 days of rest. Grazing begin on June 15/96 ending on October 1/96. Angus steers weigthing 182 ± 14.5 kg were put on the scales at the 21 days being kept out the grass from moon of the former day. Harvest efficiency (%), forage allotement (g DM/kgSW/day) daily weigth gain (g/an/day) and meat production (kg/ha) complete randomized block dessing with 2 repetitions were adopted and mean ampared using Duncan‘s test. Harvest efficiency were of 23.4 ± 3.7 %, in C1 and 71.6 ± 2.7 % in C4 differing significantly. Average forage allotments (gDM/kgSW/day) was 180.7 ± 16.7 (C1) and 16.9±0.1 (C4) differing significantly. Daily weigth gain (g/an/day) was of 870 ± 10 for C1 and 370 ± 20 for C4. Intermediate densities gave maximal production, without differing bettween then, but both there treatments with the rest (or with C1and C4). The present studies concluded that the C2 and C3 gave the must meat production, with daily weigth gains over 600 g, harvest efficiency of 65 % and allotments between 30 and 60 g/kgSW/day)

CARACTERIZACIÓN DEL CRECIMIENTO Y LA PRODUCCIÓN DE CEREALES FORRAJEROS INVERNALES EN CÓRDOBA, ARGENTINA (Characterization of the growth and production of winter forage cereals in Córdoba, Argentina

An experiment was conducted to characterize the growth and production of species and cultivars of winter forages widely used in the region. The species used were: rye (Secale cereale L.) cv. "Manfredi Suquía INTA" and "Naicó INTA"; oats (Avena sativa L.) cv. "Buck Tambera" and "Millauquén INTA", and triticale (x Triticosecale Wittmack) cv. "Tehuelche INTA", "Quiñé UNRC", "Genú UNRC", and "Tizné UNRC". The evaluation was carried out for four years (1993-96) with sowing during the first fortnight of March at densities that varied from 150 to 180 plants m-2. The measurements were made by monthly sampling leaving 7-10 cm stubble. The experimental design allowed the quantification of forage accumulated from sowing to the end of the cycle, and the re-growth occurring with different dates of first cut (50 or 79 days from sowing date). The phenological state of anthesis was considered for all entries as the moment of maximum accumulation. Dry matter accumulated during the growing period of plants without defoliation and that obtained with different first cut dates was estimated adjusting experimental values. The regression coefficients obtained and the acceptable degree of significance in most of the analyzed situations, suggest that the method offers the possibility of performing a good characterization of resources useful for comparison and, in this case in particular, to highlight the outstanding characteristics of each variety while trying to minimize costs. RESUMEN Se condujo un experimento con el objeto de caracterizar el crecimiento y la producción de las especies y variedades de forrajes de invierno más difundidas en la región. Las especies utilizadas fueron: centeno (Secale cereale L.) cvs. "Manfredi Suquía INTA" y "Naicó INTA" ; avena (Avena sativa L.) cvs. "Buck Tambera" y "Millauquén INTA" y triticale (X Triticosecale Wittmack) cvs. "Tehuelche INTA", "Quiñé UNRC", "Genú UNRC" y "Tizné UNRC". La evaluación se efectuó durante cuatro años (1993 - 1996) con siembras efectuadas durante la primera quincena del mes de marzo y densidades que oscilaron entre 150 a 180 plantas m-2. Las mediciones se realizaron mediante muestreos mensuales dejando un remanente de 7 a 10 cm. La disposición del ensayo permitió medir el forraje acumulado desde la siembra hasta finalizar el ciclo y el crecimiento producido por los rebrotes con distintas fechas de primer corte (50 y 79 días desde la siembra). El estado fenológico de antesis fue considerado para todos los participantes como el momento de máxima acumulación. La materia seca acumulada durante el período de crecimiento de plantas sin defoliar y la obtenida con distintos momentos de primer corte fue estimada ajustando los valores experimentales. Los coeficientes de regresión obtenidos y el grado de significancia en la mayoría de las situaciones analizadas, permite afirmar que el método ofrece la posibilidad de realizar una buena caracterización de los recursos evaluados con fines de comparación, y en este caso en particular, destacar las características sobresalientes de cada una de las variedades y tratar de minimizar la incidencia de los costos