Variation in nutritive value of plant parts of subterranean clover (Trifolium subterraneum L.)

2000 ◽  
Vol 40 (3) ◽  
pp. 397 ◽  
Author(s):  
Y. J. Ru ◽  
J. A. Fortune

While it has been reported that leaves of subterranean clover are less digestible than stems, there is a lack of information on the variability of nutritive value of plant parts of subterranean clover. To determine the variation in nutritive value of leaf, petiole, stem and burr, an experiment with 26 cultivars of subterranean clover was conducted at Shenton Park Field Station, Perth, Western Australia. The cultivars were divided into 3 maturity groups according to flowering time and each cultivar was sown in blocks comprising 4 replicates. The plots were grazed by sheep at 2-weekly intervals. Plants were sampled at the vegetative stage before grazing and after the cessation of flowering. Dry matter digestibility (DMD) and nitrogen concentration of leaves, petioles, stems and burrs were determined. At the vegetative stage, there was no difference in DMD (P>0.05) among plant parts for most cultivars, and leaf had the highest (P<0.05) nitrogen concentration (4.8–5.4%). After the cessation of flowering, leaf had the highest DMD and nitrogen concentration (P<0.05). The DMD of plant parts differed significantly among cultivars (P<0.05). There was a slight decrease in DMD over time for leaves and a significant decrease in DMD for stems and petioles. These results suggest the main objective of grazing management of subterranean clover swards should be to increase the proportion of leaf material in the swards and that selection of leafy varieties by breeding could improve the late season digestibility of subterranean clover. Such management and breeding strategies would have value when the cultivars are in mixed pastures or used with supplements in summer.

2001 ◽  
Vol 41 (2) ◽  
pp. 169 ◽  
Author(s):  
Y. J. Ru ◽  
J. A. Fortune

The nutritive value of 26 cultivars of dry, mature subterranean clover was evaluated at Shenton Park, Perth, Western Australia. The cultivars were divided into 3 maturity groups according to flowering time and each cultivar was sown in blocks comprising 4 replicates. The plots were grazed by sheep at 2-week intervals during the growing season. Dry mature plant material and soil were sampled in summer to examine the effect of grazing and cultivar on seed yield and nutritive value of feed residues. Cultivars heavily grazed in spring had a low herbage mass. There was no difference in seed yield and seed weight between heavily and lightly grazed cultivars. Dry matter digestibility and mineral content of dry residues was inconsistent for the 2 grazing treatments. The dry matter digestibility of dry, mature subterranean clover ranged from 40 to 56%, with a wide range of crude fibre, nitrogen and mineral content for the 26 cultivars. While most minerals in the dry residues were above the requirement for sheep, 7 cultivars had a zinc content less than the maintenance requirement for sheep. There was an imbalance for all cultivars in calcium: phosphorus with a range of 4–10: 1. Concurrent estimates on the yield and composition of seed indicated that seed can be resource of minerals for grazing animals in summer. Most cultivars had a seed yield over 100 g/m2 with that of 9 cultivars being over 130 g/m2. Seed was rich in nitrogen, sodium, phosphorus, potassium, magnesium, zinc and copper, and poor in sodium, calcium and manganese. However, there were no cultivars with an appropriate ratio of calcium and phosphorus. The imbalance in nitrogen and sulfur was a result of high nitrogen content with the ratio ranging from 19: 1 to 29: 1.


1997 ◽  
Vol 48 (8) ◽  
pp. 1199 ◽  
Author(s):  
Y. J. Ru ◽  
J. A. Fortune

Twenty-six cultivars of subterranean clover were divided into 3 maturity groups according to the flowering time and sown in 2 blocks with 4 replicates. The plots were grazed under 2 intensities (hard and lax) during the growing season. The proportions of leaf, petiole, stem, and burr before senescence, dry matter digestibility (DMD), herbage availability, and seed yield in summer were measured. The energies required to shear and compress the resultant dry mature plant materials were determined using an Instron material testing instrument. The results showed a large range for shear (11·3-18·2 kJ/m2) and compression energies (2·8-4·6 kJ/kg DM) among the 26 cultivars. Grazing intensity in spring did not affect shear energy (P > 0·05) but increased the compression energy of dry mature subterranean clover by 0·2 units (P < 0·05). The energy required to shear or compress plant materials was highly correlated with herbage availability, flowering time, proportions of leaf and petiole in the sward, and fibre content of the plant materials, with the relationships being modified by grazing intensity in spring. Compression energy was related to DMD of plants (r = -0·7) and shear energy did not account for a significant amount of variation in DMD.


2002 ◽  
Vol 29 (1) ◽  
pp. 91 ◽  
Author(s):  
Andrew P. Woolnough ◽  
William J. Foley

Near-infrared spectroscopy (NIRS) was used to predict the nutritive value of forage species available to the critically endangered northern hairy-nosed wombat (Lasiorhinus krefftii). Nutritive attributes of the forage successfully estimated included total nitrogen concentration, fibre (including neutral detergent fibre, acid detergent fibre and acid lignin), organic matter, water soluble carbohydrates and in vitro dry matter digestibility. The reported results demonstrate the seasonal variability of the forage resource available to L. krefftii in its tropical savanna habitat. Multivariate modelling of the spectra enabled the nutritive value of forage samples to be estimated with coefficients of determination (r2) of 0.770–0.995 and standard errors of the cross-validation of 0.070–2.850 using a modified partial least-squares analysis technique. The standard error of the laboratory was 0.02–1.42. This study demonstrates that broad-based NIRS predictive equations can be used to predict the nutritive value of a number of plant types available to a herbivore over time. By using NIRS the analyst can rapidly analyse large numbers of samples with limited reduction of precision, thereby enabling large-scale ecological applications that may have previously been impeded by time and costs.


1981 ◽  
Vol 32 (2) ◽  
pp. 257 ◽  
Author(s):  
DJ Reuter ◽  
AD Robson ◽  
JF Loneragan ◽  
DJ Tranthim-Fryer

Effects of severe and moderate copper deficiency on the development of leaves and lateral branches, on the distribution of dry weight within the plant, and on seed yield of Seaton Park subterranean clover were assessed as part of three glasshouse experiments. Copper deficiency markedly depressed top and root growth without producing any distinctive symptoms. It retarded phasic development by delaying development of leaves and lateral branches, senescence of plant parts, and flowering: it also depressed the proportion of stem plus petiole in plant tops and decreased internode elongation, pollen fertility and the number of burrs and seeds formed. As a result of its effect in delaying flowering, copper deficiency would depress seed production particularly strongly when low soil water supply shortens the growing season. The need for suitable procedures for diagnosing copper deficiency is emphasized by the lack of specific plant symptoms in this species.


2001 ◽  
Vol 41 (2) ◽  
pp. 177 ◽  
Author(s):  
M. D. A. Bolland ◽  
Z. Rengel ◽  
L. Paszkudzka-Baizert ◽  
L. D. Osborne

A glasshouse experiment evaluated dried herbage yield responses of dense swards of subterranean clover (Trifolium subterraneum cv. Trikkala) or Italian ryegrass (Lolium multiflorum cv. Aristocrat) to applications of different amounts of lime (0, 2.5, 5.0, 7.5, 10 and 12.5 t lime/ha) to either a loam or a sand. Yields were measured at 4 harvests [29, 51, 86 and 108 days after sowing (DAS)] when ryegrass plants had 3 leaves per tiller. Increasing amounts of lime raised the pH (1: 5, soil: 0.01 mol CaCl2/L) of the loam by 2.7 units and that of the sand by 2.0 units. Applications of lime significantly (P<0.05) increased dry herbage yields, by between 16 and 53%, for: (i) clover on the loam soil at 86 and 108 DAS, and for the sand at 108 DAS; (ii) ryegrass on the loam at 51, 86 and 108 DAS, and on the sand at 108 DAS. Increasing amounts of lime had no effect on the concentration of nutrient elements in dried herbage of either clover or ryegrass, except that the concentration of calcium increased, and the concentration of sodium, manganese and zinc (and boron for ryegrass only) all decreased. Additions of lime had no effect on dry matter digestibility, metabolisable energy, concentration of crude protein or water-soluble carbohydrates in dried herbage at any of the 4 harvests.


1973 ◽  
Vol 13 (63) ◽  
pp. 404 ◽  
Author(s):  
JG McIvor ◽  
DF Smith

Changes in herbage production, dry matter content, nitrogen content and in vitro digestibility of two sown species-subterranean clover (Trifolium subterraneum) and annual ryegrass (Lolium rigidum) - and five common volunteer species-capeweed (Arctotheca calendula), musky crowfoot (Erodium moschatum), barley grass (Hordeum leporinum), ripgut brome grass (Bromus rigidus) and soft brome grass (Bromus mollis)-were measured throughout their growth cycle. The volunteer species compared favourably with the sown species for these measurements and should be capable of providing nutritious grazing for animals.


2007 ◽  
Vol 47 (8) ◽  
pp. 927 ◽  
Author(s):  
M. D. A. Bolland ◽  
I. F. Guthridge

For the first time, we quantified pasture dry matter (DM) responses to applied fertiliser nitrogen (N) for intensively grazed, rain-fed, dairy pastures on sandy soils common in the Mediterranean-type climate of south-western Australia. The pastures are composed of subterranean clover (Trifolium subterraneum L.) and annual and Italian ryegrass (Lolium rigidum Gaud. and L. multiflorum Lam.). Six rates of N, as urea (46% N), were applied to 15 m by 15 m plots four times during 2002 and after each of the first 5–7 grazings in 2003 and 2004, throughout the typical April–October growing season. Total rates of N applied in the first year of the experiments were 0, 60, 120, 160, 200 and 320 kg N/ha, which were adjusted in subsequent years as detailed in the ‘Materials and methods’ section of this paper. The pastures in the experiments were rotationally grazed, by starting grazing when ryegrass plants had 2–3 leaves per tiller. The amount of pasture DM on each plot was measured before and after each grazing and was then used to estimate the amount of pasture DM consumed by the cows at each grazing for different times during the growing season. Linear increases (responses) of pasture DM to applied N occurred throughout the whole growing season when a total of up to 320 kg N/ha was applied in each year. No maximum yield plateaus were defined. Across all three experiments and years, on average in each year, a total of ~5 t/ha consumed DM was produced when no N was applied and ~7.5 t/ha was produced when a total of 200 kg N/ha was applied, giving ~2.5 t/ha increase in DM consumed and an N response efficiency of ~12.5 kg DM N/kg applied. As more fertiliser N was applied, the proportion of ryegrass in the pasture consistently increased, whereas clover content decreased. Concentrations of nitrate-N in the DM consistently increased as more N was applied, whereas concentrations of total N, and, therefore, concentration of crude protein in the DM, either increased or were unaffected by applied N. Application of N had no effect on concentrations of other mineral elements in DM and on dry matter digestibility and metabolisable energy of the DM. The results were generally consistent with findings of previous pasture N studies for perennial and annual temperate and subtropical pastures. We have shown that when pasture use for milk production has been maximised in the region, it is profitable to apply fertiliser N to grow extra DM consumed by dairy cows; conversely, it is a waste of money to apply N to undergrazed pastures to produce more unused DM.


1982 ◽  
Vol 33 (6) ◽  
pp. 989 ◽  
Author(s):  
DJ Reuter ◽  
JF Loneragan ◽  
AD Robson ◽  
D Plaskett

Effects of zinc supply on the distribution of zinc and dry weight among plant parts were examined during the first 55 days of vegetative development of Seaton Park subterranean clover grown in a zinc-deficient soil in a glasshouse. Symptoms of zinc deficiency first appeared in young trifoliate leaves. Zinc deficiency decreased the expansion of blades and petioles, delayed the development of leaves and lateral branches, depressed dry weights of roots and shoots, and increased the proportion of plant dry weight in roots and leaf blades. In each treatment and at each harvest, zinc concentrations varied widely amongst plant parts and with their physiological age. Plant parts also differed widely in the response of their dry matter and zinc concentrations to both zinc treatment and harvest time. It is suggested that these complex relationships explain why plant samples consisting of composite plant parts are not suitable for diagnosis of zinc deficiency. In the present experiment, zinc concentration in whole shoots was unsatisfactory for diagnosing zinc deficiency since concentrations were higher in young, zinc-deficient plants than in older, zinc-adequate plants. In young leaf blades of the same physiological age, zinc concentrations showed reasonably constant relationships with plant growth throughout the entire experiment. However, they varied two- to three-fold in leaves of different ages from the same plants. The results show the importance for diagnosis of zinc deficiency of selecting as a sample a single organ of defined physiological age. The youngest open leaf blade is recommended for diagnosis of zinc deficiency in subterranean clover.


1975 ◽  
Vol 26 (6) ◽  
pp. 975 ◽  
Author(s):  
RH Groves ◽  
JD Williams

Growth of skeleton weed (Chondrilla juncea, form A) and subterranean clover (Trifolium subterraneum) was studied in a glasshouse experiment in which the species were grown alone or together and the resultant effects of shoot and root competition assessed. The leaf number and weight of plant parts of C. juncea were reduced by competition vith subterranean clover, especially when shoots of the two species were competing. The leaf area of C. juncea was reduced, especially when roots of the two species were growing together. Puccinia chondrillina on C. juncea rosettes reduced leaf number, leaf area, and weight of plant parts. Subterranean clover grown with C. juncea infected with P. chondrillina further reduced the size and weight of the weed. The large reduction in leaf area and root weight of C. juncea (form A) plants in the presence of both subterranean clover and P. chondrillina suggests that growth of this form of C. juncea in Australia will be greatly reduced in pastures containing these species. In the long term, densities of this form may possibly be so lowered that a significant level of control will be reached in a cereal cropping-pasture system.


2001 ◽  
Vol 52 (3) ◽  
pp. 415 ◽  
Author(s):  
D. C. Cohen

An in sacco (nylon bag) technique was used to estimate the degradability of dry matter (DM) and crude protein, and to estimate the effective rumen degradability of protein (ERDP), for 3 irrigated clover herbages. Pasture characteristics (nutritive values and leaf: stem ratios) were also described, and relationships to ERDP established. The nutritive value characteristics and degradabilities of white clover (Trifolium repens L.), Persian clover (Trifolium resupinatum L.), and subterranean clover (Trifolium subterraneum L.) were also compared for various regrowth periods (of 3, 4, 6, and 12 weeks). Nutritive value characteristics of clover herbages varied from 9.9 to 11.9 MJ/kg DM for metabolisable energy, 153 to 304 g/kg DM for crude protein, and 209 to 377 g/kg DM for neutral detergent fibre. The leaf: stem ratio correlated well with the crude protein content of the clovers, with herbages consisting of more leaf generally having superior crude protein content (R2 = 0.64, P < 0.001). The effective rumen degradability of protein for clover herbages ranged from 60 g/kg DM for mature (12 week regrowth) subterranean clover to 195 g/kg DM for vegetative (3 weeks regrowth) Persian clover. For clover herbages with a 3-week regrowth period, after initial cutting to 5 cm, and at ruminal outflow rates of 0.08/h, the effective rumen degradability of protein varied from 136 to 195 g/kg DM. A positive relationship between crude protein and ERDP (R2 = 0.82) suggested that ERDP could be estimated for clover herbages that have been previously assessed for crude protein content, obviating the need for in sacco studies. Calculated degradabilities were lower for all clovers when higher ruminal outflow rates were assumed. Using the metabolisable protein system, metabolisable protein supply and metabolisable protein in excess of animal requirements were calculated. Ruminal losses of nitrogen were also estimated for cows consuming white clover of varying regrowth periods in both early and late lactation. It was concluded that metabolisable protein supply is unlikely to limit production in these examples. At regrowth periods of 3 weeks, metabolisable protein contributions from microbial and dietary sources were similar, and twice that required by the animal. Ruminal losses of nitrogen were substantial and amounted to 66—23% of nitrogen intake. In the experiments reported here, if all of the energy required to excrete excess protein (as urea) could instead be used for the production of milk, cows may have produced 0.5mp;mdash;2.0 kg more milk per day. Such losses could potentially be reduced if the protein content and/or degradabilities of clover herbages were reduced, and/or energy rich supplements were offered.


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