Residual value of molybdenum trioxide for clover production on an acidic sandy podzol

2002 ◽  
Vol 42 (5) ◽  
pp. 565 ◽  
Author(s):  
R. F. Brennan

The residual value (RV) of molybdenum (Mo) for clover (Trifolium subterraneum L.) production was measured for an acidic sand when the fertiliser was spread over the soil surface (topdressed). The RV of Mo, as molybdenum trioxide, the most widely used Mo fertiliser in Western Australia, was measured using yield of dry herbage (DM), Mo concentration of DM, and Mo content of DM (yield of DM multiplied by the Mo concentration of DM). The RV of Mo fertiliser was measured in 1993 for fertiliser Mo applied once only to plots not treated with Mo before, either in 1993 (current Mo) or 1-10 years previously (previous Mo). Relative to the nil-Mo treatment, additions of Mo fertiliser increased DM yield by about 1.20 t/ha (20% DM increase) in October. When 80 or 320 g Mo/ha was applied, all yields were on the maximum yield plateau except for Mo applied 10 years previously. The yield for the 80 g Mo/ha treatment applied 10 years earlier decreased by about 15% relative to the other current and previous Mo treatments. However, as measured using Mo concentration and Mo content in DM, there was a continuous decline in the effectiveness of previous Mo relative to current Mo the longer the previous Mo was in contact with the soil. The decrease in RV was about the same as measured using Mo concentration or content in tissue. Molybdenum applied 5 years previously was about one-third as effective as current Mo for Mo content or Mo concentration of DM.

1991 ◽  
Vol 31 (6) ◽  
pp. 777
Author(s):  
MDA Bolland

The effect of superphosphate applications (0, 25, 50, 75, 100 and 125 kg P/ha to the soil surface) on the dry matter (DM) herbage production of dense swards of subterranean clover (Trifolium subterraneum cv. Junee) and yellow serradella (Ornithopus compressus cv. Tauro) was measured in a field experiment on deep, sandy soil in south-western Australia. The swards were defoliated with a reel mower at weekly intervals from 88 to 158 days after sowing, to a height of 2 cm for the first 9 cuts, 4 cm for the tenth cut and 5 cm for the eleventh cut. Yellow serradella was more productive than subterranean clover. Consequently, for the relationship between yield and the level of phosphorus (P) applied, yellow serradella supported larger maximum yields and required less P than subterranean clover, to produce the same DM herbage yield. Maximum yields of yellow serradella were 12-40% larger. To produce 70% of the maximum yield for yellow serradella at each harvest, yellow serradella required about 50% less P than subterranean clover. However, when yields were expressed as a percentage of the maximum yield measured for each species at each harvest, the relationship between yield and the level of P applied was similar for both species, and they had similar P requirements.


2003 ◽  
Vol 43 (10) ◽  
pp. 1221 ◽  
Author(s):  
M. D. A. Bolland ◽  
J. S. Yeates ◽  
M. F. Clarke

The dry herbage yield increase (response) of subterranean clover (Trifolium subterraneum L.)-based pasture (>85% clover) to applications of different sources of sulfur (S) was compared in 7 field experiments on very sandy soils in the > 650 mm annual average rainfall areas of south-western Australia where S deficiency of clover is common when pastures grow rapidly during spring (August–November). The sources compared were single superphosphate, finely grained and coarsely grained gypsum from deposits in south-western Australia, and elemental S. All sources were broadcast (topdressed) once only onto each plot, 3 weeks after pasture emerged at the start of the first growing season. In each subsequent year, fresh fertiliser-S as single superphosphate was applied 3 weeks after pasture emerged to nil-S plots previously not treated with S since the start of the experiment. This was to determine the residual value of sources applied at the start of the experiment in each subsequent year relative to superphosphate freshly-applied in each subsequent year. In addition, superphosphate was also applied 6, 12 and 16 weeks after emergence of pasture in each year, using nil-S plots not previously treated with S since the start of the experiment. Pasture responses to applied S are usually larger after mid-August, so applying S later may match plant demand increasing the effectiveness of S for pasture production and may also reduce leaching losses of the applied S.At the same site, yield increases to applied S varied greatly, from 0 to 300%, at different harvests in the same or different years. These variations in yield responses to applied S are attributed to the net effect of mineralisation of different amounts of S from soil organic matter, dissolution of S from fertilisers, and different amounts of leaching losses of S from soil by rainfall. Within each year at each site, yield increases were mostly larger in spring (September–November) than in autumn (June–August). In the year of application, single superphosphate was equally or more effective than the other sources. In years when large responses to S occurred, applying single superphosphate later in the year was more effective than applying single superphosphate 3 weeks after pasture emerged (standard practice), so within each year the most recently applied single superphosphate treatment was the most effective S source. All sources generally had negligible residual value, so S needed to be applied each year to ensure S deficiency did not reduce pasture production.


1967 ◽  
Vol 7 (24) ◽  
pp. 25 ◽  
Author(s):  
GB Taylor ◽  
RC Rossiter

Seed production and persistence of the Carnamah, Northam A, Dwalganup, and Geraldton strains of subterranean clover (Trifolium subterraneum L.) were examined in undefoliated swards in the wheatbelt of Western Australia. The early flowering characteristic of Carnamah was not always associated with higher seed yields. Only when there was a well-defined, early finish to the growing season, or when flowering was very much earlier in Carnamah (viz., following an early 'break' to the season), did this strain clearly outyield both Northam A and Geraldton. The seed yield of Dwalganup was generally inferior to that of the other strains. Factors affecting regeneration are discussed. Under low rainfall conditions, poorer germination-regulation of Carnamah, compared with Geraldton and Northam A, would be expected to result in poorer persistence unless offset by higher seed yields in the Carnamah strain.


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.


1992 ◽  
Vol 32 (8) ◽  
pp. 1077 ◽  
Author(s):  
BH Paynter

Burr medic (Medicago polymorpha) and yellow serradella (Ornithopus compressus) were compared with subterranean clover (Trifolium subterraneum) in their response to freshly topdressed phosphate in the low rainfall wheatbelt of Western Australia. Species were compared on the amount of applied phosphorus (P) required for 90% maximum yield and the ratio of their curvature coefficients from the Mitscherlich relationship between P applied and absolute yield. On marginally acidic, medium-textured soils, burr medic had a higher external shoot requirement for applied P than subterranean clover. Relative differences between the species were affected by season, initial concentration of bicarbonate-extractable P in the soil (0-10 cm), and timing of plant harvest during the growing season. Burr medic generally achieved a higher absolute maximum yield at each harvest, a larger absolute yield response, and a larger percentage response to applied P than subterranean clover. There was no difference between burr medic and subterranean clover with respect to the internal efficiency of P use for shoot production. For seed production, the external requirements of burr medic and subterranean clover for applied P were similar according to the criterion of P required at 90% maximum yield, but burr medic had a higher requirement if curvature coefficient was the criterion for comparison. Burr medic also had a higher internal efficiency of P use for seed production than subterranean clover. On an acidic, light-textured soil, yellow serradella had a lower requirement for applied P than subterranean clover, according to both criteria for all harvests in 2 separate years.


1978 ◽  
Vol 29 (2) ◽  
pp. 225 ◽  
Author(s):  
PG Ozanne ◽  
A Petch

Three crop species, sand-plain lupin, Lupinus cosentinii L. (cv. Chapman), narrow-leaf lupin, L. angustifolius L. (cv. Uniharvest), and wheat, Triticum aestivium (cv. Gamenya), were grown under field conditions in soil fertilized then cultivated to 10 cm depth. Two annual pasture species, subterranean clover, Trifolium subterraneum L. (cv. Daliak), and Wimmera ryegrass, Lolium rigidum Gaud. (cv. Wimmera), were also grown in the field both with and without cultivation. All species were fertilized with seven levels of phosphate broadcast on the soil surface before cultivation. The amount of phosphate which produced 90% of maximum yield depended on species and cultivation practice: wheat required 98 kg phosphorus/ha; L. angustifolius, 65 kg/ha; L. cosentinii, 42 kg/ha; subterranean clover, after cultivation, 49 kg/ha; subterranean clover, not cultivated, 28 kg/ha; Wimmera ryegrass after cultivation, 40 kg/ha; Wimmera ryegrass, not cultivated, 18 kg/ha. All species except wheat required less current phosphate in this experiment than they did 3 years earlier on the same site in virgin soil. Cultivation changed the distribution of soil phosphate, and the roots of the pasture species followed the phosphate distribution.


2006 ◽  
Vol 46 (5) ◽  
pp. 659 ◽  
Author(s):  
R. F. Brennan ◽  
M. D. A. Bolland

Potassium (K) deficiency is now common in sandy soils of south-western Australia and the K requirements of most pasture species grown in rotation with crops in the region are not known. In a glasshouse experiment using a K deficient yellow sand, we compared the K requirements of 5 pasture species now commonly grown in the region: French serradella (Ornithopus sativus Brot.) cv. Cadiz, yellow serradella (Ornithopus compressus Brot.) cv. Santorini, balansa clover [Trifolium balansae, classified as T. michelianum Savi var. balansae (Boiss)] cv. Paradana, 2 subterranean clover (Trifolium subterraneum L.) cultivars, cv. Seaton Park (subspecies subterraneum) and cv. Trikkala (subspecies yanninicum), and annual ryegrass (Lolium rigidum Gaud) cv. Wimmera. After 56 days of growth, above-ground growth was harvested and analysed for total K. Mitscherlich curves were fitted to yield of dried shoots, K concentration and K content (K concentration multiplied by yield) of the shoots. These fitted curves were used to determine the amount of K required to produce 75% of the maximum yield of dried shoots, K required to attain a K concentration in dried shoots of 25 g/kg, and K required to achieve a K content in dried shoots of 250 mg K/pot. Annual ryegrass and yellow serradella more effectively used indigenous soil K and applied K to produce dried shoots than the other species and cultivars, with the other species and cultivars requiring about 55% more applied K to produce 75% of the maximum shoot yield. The K content in dried shoots estimated the total K taken up from the soil, and annual ryegrass took up least K from soil, but it required least applied K to produce 75% of the maximum shoot yield, indicating it used the K it took up very effectively to produce shoots. Yellow serradella took up most K and, after annual ryegrass, it needed least applied K to produce the target yield of dried shoots. After yellow serradella, subterranean clover cv. Trikkala took up most K from soil, but it required nearly the most applied K to produce the target shoot yield so it was inefficient at using K taken up to produce the shoots. For all the other species and cultivars, K requirement was similar as assessed by yield or K content data. The critical concentration of K required for 90% maximum yield of dried shoots was about (g K/kg) 24 for balansa clover, 23 for both subterranean clover cultivars, 21 for yellow and French serradella, and 15 for annual ryegrass.


1984 ◽  
Vol 35 (2) ◽  
pp. 201 ◽  
Author(s):  
GB Taylor

Burrs of eight varieties of subterranean clover (Trifolium subterraneum L.), which had experienced one summer at the soil surface, were placed on the soil surface and at depths of 2, 6 and 10 cm in the soil. The numbers of residual hard seeds were determined after 1, 2 and 3 years. The effects of laboratory treatment at a diurnally fluctuating temperature of 60/15�C on the softening of buried seeds and of seeds stored in the laboratory for 1 and 3 years were determined. Rate of seed softening in all varieties decreased with increasing depth of burial, apparently because the soil insulated the seeds from high soil surface temperatures. Few seeds of the varieties Northam and Geraldton softened during 3 years of burial at 6 or 10 cm; while, at the other extreme, few seeds of Yarloop survived 3 years at any depth. Some evidence was found for microbial decomposition of hard seeds in the field. Seeds softened more readily at 60/15�C (in the laboratory) as the preceding periods of either laboratory storage or field burial increased. Such storage or burial experiences have a preconditioning effect on hard seeds, making them more amenable to softening once they are subjected to wide diurnal temperature fluctuations. The results indicate that soil tillage associated with cropping should build up a useful soil seed reserve of the harder seeded varieties.


2011 ◽  
Vol 51 (1) ◽  
pp. 38-43 ◽  
Author(s):  
Jagdev Kular ◽  
Sarwan Kumar

Quantification of Avoidable Yield Losses in OilseedBrassicaCaused by Insect PestsA six year field study was conducted from 2001-2002 to 2006-2007 at Punjab Agricultural University, Ludhiana, India to study the losses in seed yield of differentBrassicaspecies (B. juncea, B. napus, B. carinata, B. rapaandEruca sativa) by the infestation of insect pests. The experiment was conducted in two different sets viz. protected/sprayed and unprotected, in a randomized block design, with three replications. Data on the infestation of insect pests, and seed yield were recorded at weekly intervals and at harvest, respectively. The loss in seed yield, due to mustard aphid and cabbage caterpillar, varied from 6.5 to 26.4 per cent.E. sativasuffered the least loss in seed yield and harboured the minimum population of mustard aphid (2.1 aphids/plant) and cabbage caterpillar (2.4 larvae/plant). On the other hand,B. carinatawas highly susceptible to the cabbage caterpillar (26.2 larvae/plant) and suffered the maximum yield loss (26.4%).


1980 ◽  
Vol 16 (2) ◽  
pp. 117-125 ◽  
Author(s):  
R. W. Willey ◽  
M. R. Rao

SUMMARYA simple competitive ratio (CR) is proposed as a measure of intercrop competition, to indicate the number of times by which one component crop is more competitive than the other. Intercropping data show that this CR term could be useful in (i) comparing the competitive ability of different crops, (ii) measuring competitive changes within a given combination, (iii) identifying which plant characters are associated with competitive ability, and (iv) determining what competitive balance between components is most likely to give maximum yield advantages.


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