FORAGE CROP MATURITY ZONATION IN THE ATLANTIC REGION USING GROWING DEGREE-DAYS

1984 ◽  
Vol 64 (2) ◽  
pp. 329-338 ◽  
Author(s):  
A. BOOTSMA

Accumulated growing degree-days above 5 °C (GDD) were used to estimate the average time of occurrence of maturity stages before first harvest in post seeding years for alfalfa (Medicago sativa L.), double cut red clover (Trifolium pratense L.) and timothy (Phleum pratense L.) in the Atlantic region of Canada. Maturity stages recommended for first cut were reached after an average accumulation of approximately 350, 400 and 450 GDD, depending upon the cultivar. Estimates of maturity dates based on the average air temperature (T) for May and June were highly correlated with annually observed dates of selected maturity stages [Formula: see text]. T was also used to estimate regional variation in maturity dates based on normals for the 1951–1980 period from 231 climate stations. Eight maturity zones (M1 to M8) were designated for the region. Estimated average dates when forage cultivars reach maturity stages recommended for first cut ranged from on or before 15 June–25 June in the Annapolis and Saint John River valleys to after mid-July in parts of Newfoundland.Key words: Medicago sativa L., Phleum pratense L., Trifolium pratense L., cutting date, temperature, zonation

1985 ◽  
Vol 65 (3) ◽  
pp. 573-580 ◽  
Author(s):  
A. BOOTSMA ◽  
MICHIO SUZUKI

Air temperature normals (1951–1980 period) were analyzed for over 200 locations in the Atlantic region to estimate spatial and temporal variations in the critical autumn period during which alfalfa (Medicago sativa L.) should not be harvested to allow plants to reach adequate winter hardiness by accumulating sufficient food reserves in the roots. Data are presented which show that the starting date of the critical harvest period could be estimated from the average date when 450 growing degree-days above 5 °C remain in autumn (F450). F450 compared well with starting dates determined experimentally in 3 yr of field tests at three locations in Ontario. F450 varied from before 10 Aug. in northwestern New Brunswick and parts of Newfoundland to after 4 Sept. in southwestern Nova Scotia. Annual differences in climate cause F450 to vary with a standard deviation of about 5–6 days at a given location. A zonation map describing spatial variation in the rest period was prepared as a general guide for cutting management.Key words: Alfalfa, Medicago sativa L., cutting management, winter survival, climate zonation


1982 ◽  
Vol 62 (1) ◽  
pp. 145-154 ◽  
Author(s):  
UMESH C. GUPTA ◽  
K. A. WINTER ◽  
K. B. McRAE

Two separate field experiments were conducted on several crops to determine the effect of selenium (Se) applied to soils with pH levels between 5.7 and 6.6. Tissue Se levels after a single application of Se and lime, were monitored for up to six cropping years or until the tissue Se fell below 0.1 ppm, the level considered to be necessary for animal nutrition. For applications of 1.12 and 2.24 kg Se/ha, the minimal tissue Se concentration (> 0.1 ppm) was maintained in barley (Hordeum vulgare L.) for two cropping years, but with a very sharp decrease for the first 3 yr. In the case of timothy (Phleum pratense L.), tissue levels greater than 0.1 ppm were maintained for 3 yr at the higher rate of Se without lime and up to 5 yr at high soil pH levels. At the applied rates of 0.28 and 0.56 kg Se/ha, the tissue Se levels above 0.1 ppm in timothy, red clover (Trifolium pratense L.), and alfalfa (Medicago sativa L.) were maintained for one and two cropping years, respectively. In spite of the sharp decrease in plant tissue Se levels, little decrease in total soil Se was noted at rates of 1.12 and 2.24 kg Se/ha after successive croppings of barley and timothy. Although not always significant, liming, in general, increased the plant Se concentration. The Se concentration (log ppm) for tissues (or depletion of Se availability) in the Se-applied plots decreased linearly for at least the first three cropping seasons.


1973 ◽  
Vol 53 (3) ◽  
pp. 431-438 ◽  
Author(s):  
D. P. HEANEY

Red clover (Trifolium pratense L.), first- and second-cut alfalfa (Medicago sativa L.), timothy (Phleum pratense L.) hays, and oat (Avena sativa L.) straw were assayed for digestible dry matter (DDM) and dry matter intake (DMI) using sheep with various opportunities for feed selection provided by varying weighbacks between 0 and 30%. Digestible energy intakes (DEI) were also calculated. There was a slight increase in DMI values as the opportunity for selection increased, due to slightly lower DMI at low levels of weighback and higher DMI as weighback approached 30%. There were no changes in DMI due to the opportunity for selection when weighbacks varied only from 5 to 25%. Except for an apparent curvilinear relationship for the first-cut alfalfa, the change in DDM as the opportunity for selection increased was similar to that of DMI. However, the maximum changes in DDM that could be attributed to the opportunity for selection would be barely detectable in normal digestion trials. Changes in DEI attributable to the opportunity for selection were caused primarily by DMI rather than digestibility. DEI showed a slight increase as weighback increased, due to lower values at low levels of weighback and, in some cases, higher values at higher levels of weighback. There were no changes in DEI values that could be attributed to the opportunity for selection when weighbacks varied only from 5 to 25%. The data indicate that, for forage evaluation purposes, DMI and DDM can be assayed with confidence at levels of weighback between 5 and 20%.


1985 ◽  
Vol 65 (3) ◽  
pp. 787-791
Author(s):  
H. A. BURITY ◽  
B. E. COULMAN ◽  
M. A. FARIS

A greenhouse experiment has shown that total nitrogenase activity of alfalfa (Medicago sativa L.) is not significantly affected when grown in association with timothy (Phleum pratense L.), smooth bromegrass (Bromus inermis Leyss) or orchardgrass (Dactylis glomerata L.) except after initial harvest when decreased alfalfa activity was associated with smooth bromegrass or orchardgrass. It was concluded that mixed cultures of alfalfa with timothy, smooth bromegrass or orchardgrass have no effect on alfalfa N2 fixation. The results also suggest the occurrence of N transference from alfalfa to associated grasses. It is speculated that this transfer is not primarily due to the death of roots and nodule tissue (after harvest), but involves some degree of N excretion during the period before initial harvest.Key words: Alfalfa-grass mixtures, N2-fixation, nodule activity, N-transference


2013 ◽  
Vol 67 (1) ◽  
pp. 95-101 ◽  
Author(s):  
Snezana Jaksic ◽  
Savo Vuckovic ◽  
Sanja Vasiljevic ◽  
Nada Grahovac ◽  
Vera Popovic ◽  
...  

Recently, heavy metals concentrations increased in some agricultural areas due to the consequences of anthropogenic impacts. The aim of this study was to determine the level of heavy metals (As, Cr, Ni and Pb) in Medicago sativa L. and Trifolium pratense L. grown on fluvisol, in order to obtain information on safety of these nutrients. The total content of Pb, As, Cr and Ni in the samples of fluvisol was above the maximum allowable amount. The content of heavy metals in Medicago sativa L. and Trifolium pratense L. was below the critical and toxic concentrations in all samples originating from contaminated soil. It was concluded that the accumulation of heavy metals in plants did not depend only on the total content in soil, but also the affinity of the plant, and individual and interactive effects of various soil properties. No statistically significant differences in the accumulation of heavy metals between Medicago sativa L. and Trifolium pratense L were observed. It is necessary to further control of heavy metals in the investigated area, in order to prevent their entry into the food chain and provide healthy food.


1987 ◽  
Vol 67 (4) ◽  
pp. 1101-1103 ◽  
Author(s):  
LUCIUS BELZILE

The influence of timothy (Phleum pratense L.) on winter survival of red clover (Trifolium pratense L.) was studied in an experiment conducted in 1984–1985 and repeated in 1985–1986. The results indicate that the presence of timothy can help to improve red clover persistence. When the winter was favorable to the survival of legumes, the red clover population was higher in pure than in mixtured clover populations. However, when the winter was unfavorable to legumes, the red clover population was higher in populations mixed with timothy than in a pure clover population.Key words: Red clover-timothy mixture, winter survival, stand, yield


2021 ◽  
Vol 32 (1) ◽  
pp. e19491
Author(s):  
Carlos Estupiñán M. ◽  
Fernando Carcelén C. ◽  
Víctor Hidalgo L. ◽  
David Rojas E. ◽  
Oscar Vera C. ◽  
...  

El objetivo del presente estudio fue determinar la aplicabilidad de la espectroscopía del infrarrojo cercano (NIRS) para la valoración nutritiva de dos especies forrajeras de importancia en el país: alfalfa (Medicago sativa L) y trébol rojo (Trifolium pratense L). Se utilizaron 75 muestras de variedades de alfalfa (SW 8210, WL 625HQ) y 75 de variedades de trébol rojo (Quiñequeli, Kendland) obtenidas de los campos de la Estación Experimental IVITA El Mantaro, región Junín, Perú. Se realizó el análisis proximal determinando el contenido de proteína cruda (PC), extracto etéreo (EE), fibra cruda (FC), cenizas totales (CZ) y fibra detergente neutra (FDN) y se hizo la captura del espectro mediante un equipo NIRS. Se elaboraron los modelos de calibración y validación para estimar la capacidad predictiva mediante Cuadrados Mínimos Parciales (PLS), siendo los estadísticos de exactitud y precisión usados el Coeficiente de Correlación (R), Coeficiente de Determinación (R2), Raíz Cuadrada Media del Error de Calibración (RMSEC), Raíz Cuadrada Media del Error de Predicción (RMSEP), Proporción del Rango con el Error (RER) y Desviación Residual Predictiva (RPD). Los modelos matemáticos obtenidos muestran que la técnica NIRS posee una capacidad de predicción buena de los componentes nutricionales de PC, CZ y FDN (R2:0.97, 0.99, 0.94; RPD: 2.00, 2.17 y 2.00, respectivamente) para variedades de alfalfa y trébol rojo.


2019 ◽  
Vol 230 (12) ◽  
Author(s):  
Marie Davin ◽  
Amandine Starren ◽  
Emilie Marit ◽  
Kévin Lefébure ◽  
Marie-Laure Fauconnier ◽  
...  

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