Polysaccharide composition of Australian wheats and the digestibility of their starches in broiler chicken diets

1990 ◽  
Vol 30 (2) ◽  
pp. 183 ◽  
Author(s):  
G Annison

The polysaccharide compositions of 20 wheat varieties from New South Wales and Western Australia were determined. Mean pentosan and �-glucan contents ranged from 5.7 1 to 8.18% and from 0.61 to 0.87% respectively, on a dry matter basis. Starch contents ranged from 61.5 to 68.9% and the wheat starches were between 21.1 and 31.8% amylose. The starch digestibility of the wheats was found to be independent of the levels or composition of the polysaccharides when assayed using 5-week-old broiler chickens.

1992 ◽  
Vol 32 (4) ◽  
pp. 447 ◽  
Author(s):  
G Sweeney ◽  
RS Jessop ◽  
H Harris

The yields and yield structure of cultivars of triticales and bread wheats (with a range of phasic development patterns in both species) were compared in 2 field experiments at Narrabri in northern New South Wales. The experiments were performed on a grey cracking clay soil with irrigation to prevent severe moisture stress. Triticales, both early and midseason types, appeared to have reached yield parity with well-adapted wheat varieties. Meaned over the 2 experiments and all sowings, the triticales yields were 19% greater than the bread wheats. Triticales were generally superior to wheat in all components of yield of the spike (1000-grain weight, grain number/spikelet and spikelet number/spike), whilst the wheats produced more spikes per unit area. The triticales also had higher harvest indices than the wheats. The results are discussed in relation to the overall adaptability of triticale for Australian conditions.


1998 ◽  
Vol 38 (6) ◽  
pp. 567 ◽  
Author(s):  
G. C. Anderson ◽  
R. D. B. Lefroy ◽  
G. J. Blair

Summary. A glasshouse experiment was conducted to study the correlation between various soil sulfur (S) extractants and pasture response to applied S grown under controlled environmental conditions (glasshouse) as influenced by variations in levels of extractable S. Intact paired soil cores were collected at 2-month intervals from an S x P factorial experiment at 4 field sites on the Northern Tablelands of New South Wales on 11 occasions. Soil samples were collected from each core and the cores placed in the glasshouse. Sulfur was applied to one core of each pair and basal nutrients applied to all cores which were then oversown with white clover (Trifolium repens L. cv. Haifa). The extractable S in the soil was analysed using the following techniques: 0.1 mol Ca(H2PO4)2/L (MCPt); 0.1 mol Ca(H2PO4)2/L, treated with activated charcoal (MCPi); water (H2O); 0.25 mol KCl/L, heated at 40°C for 3 h (KCl-40); 0.25 mol KCl/L, heated at 100°C for 4 h (KCl-100); 0.5 mol NaHCO3/L (NaHCO3); and an acid digestion of the soil (total). Dry matter yield and S content of the pasture shoots were measured for each 2-month growth period. The relationship between the various soil S extraction techniques and the response of pasture to applied S varied over time and was influenced by the level of inorganic S present in the soil and the amount of organic S extracted. When the level of MCPi-extractable S ranged between 2 and 22 µg S/g soil due to the application of fertiliser (summer 1987–88 and autumn 1988), or after a period of high mineralisation rates (spring 1988), the MCPi, MCPt, H2O and KCl-40 techniques had the highest correlation with the increase in S content of the pasture when S was applied. The higher correlation for the MCPt, H2O and KCl-40 techniques than the MCPi technique indicates that plants obtained some S from the organic S pool. In contrast, when the levels of MCPi-extractable S ranged between 2 and 10 µg S/g soil and the rate of mineralisation increased in response to an increase in soil temperature (June 1988 and June 1989) or moisture (September 1989) upon transfer of samples from the field to the glasshouse, the MCPt, H2O and KCl-40 techniques underestimated the available S pool and had lower r2 values than either the KCl-100 or NaHCO3 techniques.


1975 ◽  
Vol 15 (77) ◽  
pp. 795 ◽  
Author(s):  
JA Thompson

A range of temperate annual and perennial legumes, naturalized or commonly sown in the area, was examined at three field sites in low fertility soils derived from granite on the south western slopes of the New England Region, New South Wales. They were compared over a four year period in terms of their persistence, dry matter and nitrogen production and their compatibility with associated temperate perennial grasses, The response of sown grass to nitrogen fertilizer application was also examined in the absence of legume. Ten legumes were examined at one site and six of these at the other two sites. In general, nitrogen yields were ranked similarly to total dry matter yields of all treatments, including grasses in the absence of legume. However, the legumes were ranked differently in terms of productivity of the legume component and productivity of associated grass. At all sites lucerne gave the highest yields of total dry matter and of legume and the lowest yield and persistence of associated grass-comparable to grass growing in the absence of legume or applied nitrogen. Subterranean clover was ranked second or third in total dry matter yield, depending on site, but provided the highest yield of associated grasscomparable to grass receiving high levels of applied nitrogen. Under this legume soil nitrogen levels tended to be highest. Rose clover, sown at one site only, yielded more legume dry matter than subterranean clover but grass yield was comparable to that with lucerne. The results suggest that subterranean clover is the superior legume for successful mixed sowings although inclusion of white clover could be justified. Lucerne appears to be best sown as a pure sward.


1971 ◽  
Vol 11 (50) ◽  
pp. 307 ◽  
Author(s):  
GJ Murtagh

The effectiveness of chemical seedbed preparation for sod-sown oats was studied using varying intervals between spraying and sowing. Four herbicides were compared in a second experiment. Both experiments were conducted on paspalum (Paspalum dilatatum) dominant pastures on red basaltic soil on the North Coast of New South Wales. Herbicides were most effective when applied at 6.7 kg acid equivalent a hectare. At this rate, the highest yields of dry matter and nitrogen were obtained when there was a three-week interval and considerably less when there was no interval. A mixture of 2,2-DPA (2,2-dichloropropionic acid) and amitrole (3-amino-1,2,4-triazole) was more effective than 2,2-DPA alone with a three-week spraying interval but there was no difference with a six-week interval. Both amitrole and a mixture of amitrole and ammonium thiocyanate were ineffective for chemical seedbed preparation on paspalum pastures;


1993 ◽  
Vol 33 (2) ◽  
pp. 245 ◽  
Author(s):  
PG Tow

The persistence and water use efficiency of Digitaria eriantha spp. eriantha and Hunter river lucerne were compared on red solodic soil with a hardsetting surface and poor internal drainage, on the North- West Slopes of New South Wales. After prolonged watering, the profile was wet to a depth of 48 � 1.5 cm, with an available moisture store of 90 mm. Over 3 years, persistence of digitaria was excellent. The population of lucerne was reduced following flooding at summer temperatures, Dry matter production of nitrogen (N) fertilised digitaria per mm warm season rainfall was similar to that of tropical grasses adapted to comparable rainfall environments in subtropical Queensland. Lucerne dry matter per mm rainfall was only about half that of digitaria (3.2 v. 6.3 kg). Lucerne grew well in mixture with digitaria except under prolonged wet soil conditions in summer. Artificial solodic profiles were constructed in the glasshouse to compare digitaria and lucerne in monoculture and mixture under varying temperature, moisture, and N regimes. Lucerne showed sensitivity to both high and low moisture levels at summer temperatures but performed very well at spring temperatures and moderate moisture levels where the mean evapotranspiration ratio was 400 g water per g dry matter. Water use efficiency was higher in digitaria than in lucerne, except at spring temperatures without added N. Water use efficiency of the mixture was always similar to that of the most efficient monoculture of the particular treatment.


1995 ◽  
Vol 35 (1) ◽  
pp. 93 ◽  
Author(s):  
RD FitzGerald ◽  
ML Curll ◽  
EW Heap

Thirty varieties of wheat originating from Australia, UK, USA, Ukraine, and France were evaluated over 3 years as dual-purpose wheats for the high rainfall environment of the Northern Tablelands of New South Wales (mean annual rainfall 851 mm). Mean grain yields (1.9-4.3 t/ha) compared favourably with record yields in the traditional Australian wheatbelt, but were much poorer than average yields of 6.5 t/ha reported for UK crops. A 6-week delay in sowing time halved grain yield in 1983; cutting in spring reduced yield by 40% in 1986. Grazing during winter did not significantly reduce yields. Results indicate that the development of wheat varieties adapted to the higher rainfall tablelands and suited to Australian marketing requirements might help to provide a useful alternative enterprise for tableland livestock producers.


2004 ◽  
Vol 44 (12) ◽  
pp. 1165 ◽  
Author(s):  
A. M. Bowman ◽  
W. Smith ◽  
M. B. Peoples ◽  
J. Brockwell

Total productivity and legume nitrogen fixation (N2 fixation) in dryland pastures were examined in a 2 year study (1999–2001) on 118 farms in central-western New South Wales. Pasture exclosure cages, placed at 217 on-farm sites, were harvested on 7 occasions and the foliage hand-sorted according to species in order to measure shoot dry matter (DM). The separated legume shoot material collected in spring 1999 (52 different legume samples) and 2000 (76 different legume samples) from a subset of representative pastures (41 cages on 28 different farms in 1999, 32 cages on 25 different farms in 2000) was also analysed for concentration of nitrogen (%N) and 15N natural abundance. These data were subsequently used to calculate the proportion of the legume shoot N derived from atmospheric N (%Ndfa), comparative measures of the relative efficiency of N2 fixation (kg N fixed/t DM accumulated) and the amounts of shoot N fixed (kg N/ha). The survey encompassed 8 common pasture types, and 5 others that were less common, ranging from native perennial grass pastures with little legume content to lucerne (Medicago sativa L.) pastures with and without companion clovers. Fifteen legume species were found in the pastures, some only occasionally. Lucerne and white clover (Trifolium repens L.) were the only perennials. Mean spring estimates of %Ndfa were similar in 1999 and 2000 for lucerne (72 and 81%, respectively), rose clover (T. hirtum All., 82 and 77%) and annual medics (Medicago spp., 89 and 86%). For the remaining 12 legume species, measures of %Ndfa ranged from 64 to 95% and averaged 83%. Shoot %N contents were greater for lucerne than for the other 14 legumes and this was reflected in the comparative measures of N2 fixation which ranged from 14.5 kg N/t DM for rose clover to 25.7 kg N/t DM for lucerne in 2000. The most productive pasture type comprised lucerne plus balansa clover [T. michelianum Savi var. balansae (Boiss.) Azn.], white clover or arrowleaf clover (T. vesiculosum Savi), but all pasture types that contained lucerne were highly productive. Spring was the most productive season and summer the least. Lucerne was overwhelmingly the most productive legume and was responsible for >83% of the fixed N in those pastures that contained both lucerne and other legumes. Lucerne productivity was approximately uniform throughout the year whereas, for other pastures, especially those based on rose clover or subterranean clover (T. subterraneum L.), there were sharp peaks in spring and little or no dry matter production over summer. The presence of lucerne in pastures significantly (P<0.05) reduced broadleaf weeds. It was concluded that, where there are requirements in central-western New South Wales agriculture for uniform forage production throughout the year and a high input of fixed N, lucerne is substantially superior to other species.


1991 ◽  
Vol 31 (5) ◽  
pp. 639 ◽  
Author(s):  
PL Milthorpe ◽  
PR Dann

In 1985, experiments were conducted at 4 localities in south-eastern and central New South Wales, to assess the production potential of tagasaste. The results were disappointing: 2 experiments failed to establish because of soil waterlogging, while production from the other 2 sites was only intermittent. Annual dry matter production did not exceed 3 t/ha at Condobolin or 5 t/ha at Yass. Although survival of established plants was good, production was limited by prolonged dry periods at Condobolin and by low temperatures during winter at Yass. Tagasaste is costly to establish (up to $A500/ha) and difficult to manage. In our environments, conventional pastures or fodder crops which require simpler management would probably out-produce tagasaste at most times during the experimental period.


1984 ◽  
Vol 24 (125) ◽  
pp. 236
Author(s):  
GK McDonald ◽  
BG Sutton ◽  
FW Ellison

Three winter cereals (wheat varieties Songlen and WW 15, triticale variety Satu) were grown after cotton or summer fallow under three levels of applied nitrogen (0, 100 and 200 kg N/ha) at Narrabri, New South Wales. The cereals were sown on August 7, 1980 and growing season rainfall was supplemented by a single irrigation. Leaf area, total shoot dry matter production and ears per square metre were lower after cotton than after summer fallow, while grain yields of cereals sown immediately after cotton were 33% lower than those sown after fallow. Adding nitrogen increased leaf area, dry matter and grain yields of crops grown after cotton and fallow, but significant increases were not obtained with more than 100 kg/ha of applied nitrogen. Crops grown after cotton required an application of 100 kg N/ha for leaf and dry matter production at anthesis to equal that of crops grown after fallow with no additional nitrogen. The corresponding cost to grain yield of growing cotton was equivalent to 200 kg N/ha. The low grain yield responses measured in this experiment (1 8 and 10% increase to 100 kg N/ha after cotton and fallow, respectively) were attributed to the combined effects of late sowing, low levels of soil moisture and loss, by denitrification, of some of the applied nitrogen. The triticale, Satu, yielded significantly less than the two wheats (1 99 g/m2 for Satu c.f. 255 and 286 g/m2 for Songlen and WW 15, respectively), and did not appear to be a viable alternative to wheat in a cotton rotation.


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