Effect of split nitrogen applications on the yield and protein content of dryland wheat in northern New South Wales

1991 ◽  
Vol 31 (1) ◽  
pp. 85 ◽  
Author(s):  
AD Doyle ◽  
RA Shapland

Experiments were conducted with dryland wheat on a nitrogen (N) deficient site near Gunnedah, northern New South Wales, in 1987 and 1988 to compare post-sowing foliar applications of N with urea drilled between the rows at sowing. Post-sowing N was applied at tillering, booting or at both stages at rates of 20 or 40 kg N/ha while presowing applications ranged from 0-106 kg N/ha. Above ground dry weight and N uptake increased with increasing N application at sowing. Post-sowing N application increased dry weight and N uptake, with generally greater increases in N uptake than in dry weight. Dry weight and N uptake for post-sowing N application were invariably less than when an equivalent amount of N had been applied at sowing. Grain yield was increased by the application of up to 106 kg N/ha at sowing in 1987 and up to 80 kg N/ha in 1988 when a greater degree of moisture stress during grain filling restricted yield responses. Post-sowing N increased grain yield, but the yield response was lower than for the application of an equivalent amount of N at sowing. Grain yield responses were lower when N was applied at booting rather than tillering. Yield responses over the 2 years were 0.35-0.39 t/ha and 0.44-0.68 t/ha for 20 and 40 kg N/ha, respectively, applied at tillering and 0.26-0.4 t/ha and 0.26-0.48 t/ha for N application at booting. Post-sowing N application increased grain protein, with greater increases for booting than for tillering applications. There was an apparent recovery in the grain of 48-56% of N applied at sowing, but only 25-48% of N applied post-sowing.

1992 ◽  
Vol 32 (3) ◽  
pp. 383 ◽  
Author(s):  
AD Doyle ◽  
CC Leckie

Grain yield, protein, and nitrogen uptake responses are reported for 6 wheat fertiliser experiments in northern New South Wales which were representative of sites that were highly responsive, moderately responsive, and non-responsive to nitrogen (N) fertiliser applied at sowing. Apparent recoveries of applied N of 33-57% in the grain were recorded where grain yield was steeply increasing in response to additional applied N. Where yield increases were smaller in response to increments of N fertiliser, N recovery was 22-3096, but where further N application increased grain protein content but not grain yield, apparent recovery of additional fertiliser N fell below 20%. Apparent recovery was less than 10% in experiments where there was no yield response to N fertiliser. The implications for fertiliser recommendations are discussed relative to potential premium payment for wheat protein levels. It was concluded that established premium payments are too low to make N application an economic proposition to increase grain protein levels in the absence of grain yield responses.


1994 ◽  
Vol 34 (7) ◽  
pp. 1013
Author(s):  
LM Kealey ◽  
E Humphreys ◽  
AS Black ◽  
WA Muirhead

Presowing nitrogen (N) fertiliser management for aerial-sown rice was investigated for 2 soil cultivation methods, conventional cultivation and puddling, in the Coleambally Irrigation Area of New South Wales. Two N sources, urea and anhydrous ammonia (NH3, ColdFlo), were used. Urea was applied at 3 depths (0,7, 17 cm) and NH3 at 2 depths (7, 17 cm). These 5 treatments were compared with an unfertilised control and with a novel method of applying NH3 in the same operation as puddling. Urea was applied at 60 kg N/ha; the application rate of NH3 appeared to be higher than the intended rate of 60 kg N/ha. The site was responsive to N: agronomic efficiency of the urea-fertilised treatments averaged 39 kg grain yield increase/kg applied N. Dry matter yield, N uptake, and grain yield were similar on conventionally cultivated and puddled soil. There were no significant interactions between cultivation and N treatments in their effects on crop growth or N uptake. Application depth of fertiliser also had no significant effect on crop performance. Applying NH3 in the same operation as puddling was as effective as other methods of applying N, with the advantage of allowing soil preparation and fertiliser application to be completed in 1 pass. Urea labelled with 15N was applied at depths of 0, 5, and 15 cm to microplots at a rate of 60 kg N/ha. Recoveries of 15N in plants and soil were similar for both methods of soil cultivation and for different N application depths, consistent with results from the large plots described above. There was no interaction between soil cultivation and urea application depth treatments. Recovery of applied 14N averaged 32% in the plant shoots and 24% in the top 30 cm of the soil. Recoveries of 15N from presowing urea application have not previously been reported for aerial-sown rice in New South Wales. The results suggest that puddling can be readily integrated into the rice management system without changing current fertiliser practices. However, soil N uptake was very high, accounting for around 90% of the plant N uptake in the urea-fertilised treatments. Therefore, extrapolation of the results of the treatment comparisons to other sites with lower available N should only be done with caution.


2015 ◽  
Vol 66 (4) ◽  
pp. 349 ◽  
Author(s):  
Julianne M. Lilley ◽  
Lindsay W. Bell ◽  
John A. Kirkegaard

Recent expansion of cropping into Australia’s high-rainfall zone (HRZ) has involved dual-purpose crops suited to long growing seasons that produce both forage and grain. Early adoption of dual-purpose cropping involved cereals; however, dual-purpose canola (Brassica napus) can provide grazing and grain and a break crop for cereals and grass-based pastures. Grain yield and grazing potential of canola (up until bud-visible stage) were simulated, using APSIM, for four canola cultivars at 13 locations across Australia’s HRZ over 50 years. The influence of sowing date (2-weekly sowing dates from early March to late June), nitrogen (N) availability at sowing (50, 150 and 250 kg N/ha), and crop density (20, 40, 60, 80 plants/m2) on forage and grain production was explored in a factorial combination with the four canola cultivars. The cultivars represented winter, winter × spring intermediate, slow spring, and fast spring cultivars, which differed in response to vernalisation and photoperiod. Overall, there was significant potential for dual-purpose use of winter and winter × spring cultivars in all regions across Australia’s HRZ. Mean simulated potential yields exceeded 4.0 t/ha at most locations, with highest mean simulated grain yields (4.5–5.0 t/ha) in southern Victoria and lower yields (3.3–4.0 t/ha) in central and northern New South Wales. Winter cultivars sown early (March–mid-April) provided most forage (>2000 dry sheep equivalent (DSE) grazing days/ha) at most locations because of the extended vegetative stage linked to the high vernalisation requirement. At locations with Mediterranean climates, the low frequency (<30% of years) of early sowing opportunities before mid-April limited the utility of winter cultivars. Winter × spring cultivars (not yet commercially available), which have an intermediate phenology, had a longer, more reliable sowing window, high grazing potential (up to 1800 DSE-days/ha) and high grain-yield potential. Spring cultivars provided less, but had commercially useful grazing opportunities (300–700 DSE-days/ha) and similar yields to early-sown cultivars. Significant unrealised potential for dual-purpose canola crops of winter × spring and slow spring cultivars was suggested in the south-west of Western Australia, on the Northern Tablelands and Slopes of New South Wales and in southern Queensland. The simulations emphasised the importance of early sowing, adequate N supply and sowing density to maximise grazing potential from dual-purpose crops.


1981 ◽  
Vol 32 (6) ◽  
pp. 967 ◽  
Author(s):  
RWJ Pidgeon

The diets and growth rates of rainbow trout in the Wollomombi and Guy Fawkes Rivers in northern New South Wales were examined. The growth rate of trout in the Wollomombi River was much higher than that of fish in the Guy Fawkes River. Spearman rank correlation coefficients indicated that stream type was more important than fish size in determining the composition of the diet of the trout. Benthic invertebrates formed the largest component of the diet in both streams: 66.0 and 63.0% of ash-free dry weight (AFDW) in the Wollomombi River and the Guy Fawkes River, respectively. Trout in the Wollomombi River consumed more nektonic prey (33.3% of AFDW) than fish in the Guy Fawkes River (3.7% of AFDW). In contrast, surface food (aquatic imagines and terrestrial insects) made up a much higher proportion of the diet of trout in the Guy Fawkes River (33.9% of AFDW) than in the Wollomombi River (0.6% of AFDW). Crayfish were a major component of the diet (in terms of AFDW) in both streams, their proportions increasing with fish size. The significance of crayfish in relation to fish growth is discussed.


2003 ◽  
Vol 43 (1) ◽  
pp. 71 ◽  
Author(s):  
M. K. Conyers ◽  
C. L. Mullen ◽  
B. J. Scott ◽  
G. J. Poile ◽  
B. D. Braysher

The cost of buying, carting and spreading limestone, relative to the value of broadacre crops, makes investment in liming a questionable proposition for many farmers. The longer the beneficial effects of limestone persist, however, the more the investment in liming becomes economically favourable. We re-established previous lime trials with the aim of measuring the long-term effects of limestone on surface acidity (pH run-down), subsurface acidity (lime movement) and grain yield. The study made use of experiments where there was adequate early data on soil chemical properties and cereal yields. We report data from 6 trials located at 4 sites between Dubbo and Albury in New South Wales. The rate of surface soil (0–10 cm) pH decline after liming was proportional to the pH attained 1 year after liming. That is, the higher the pH achieved, the more rapid the rate of subsequent pH decline. Since yields (product removal) and nitrification (also acid producing) may both vary with pH, the post-liming pH acts as a surrogate for the productivity and acid-generating rate of the soil–plant system. The apparent lime loss rate of the surface soils ranged from the equivalent of nearly 500 kg limestone/ha.year at pH approaching 7, to almost zero at pH approaching 4. At commercial application rates of 2–2.5 t/ha, the movement of alkali below the layer of application was restricted. However, significant calcium (Ca) movement sometimes occurred to below 20 cm depth. At rates of limestone application exceeding the typical commercial rate of 2.5 t/ha, or at surface pH greater than about 5.5, alkali and Ca movement into acidic subsurface soil was clearly observed. It is therefore technically feasible to ameliorate subsurface soil acidity by applying heavy rates of limestone to the soil surface. However, the cost and risks of this option should be weighed against the use of acid-tolerant cultivars in combination with more moderate limestone rates worked into the surface soil.There was a positive residual benefit of limestone on cereal grain yield (either barley, wheat, triticale, or oats) at all sites in both the 1992 and 1993 seasons. While acid-tolerant cultivars were less lime responsive than acid-sensitive ones, the best yields were generally obtained using a combination of liming and acid-tolerant cultivars.The long-term residual benefits of limestone were shown to extend for beyond 8–12 years and indicate that liming should be profitable in the long term.


1968 ◽  
Vol 8 (35) ◽  
pp. 767
Author(s):  
RN Allen

Control of post-emergence damping-off, basal stem rot, and root rot of vetch (Vicia sativu) caused by Pythium debaryanum and other pythiaceous fungi, was obtained in a sod-sown field trial at Wollongbar, New South Wales, by applying the fungicide Dexon (R) (p-dimethylaminobenzenediazo sodium sulphonate) with the fertilizer in the furrow at sowing. Dexon improved plant establishment and survival, and increased plant vigour in the early stages of growth. Dry matter yield of vetch was increased from 206 lb an acre without Dexon, to 604 lb an acre with Dexon applied at 8 oz an acre (4.3 mg per row ft), with a corresponding reduction in the cost of fodder produced. Yield responses were also obtained at lower and higher rates, but at 64 oz an acre the Dexon was phytotoxic and no yield response was observed despite excellent disease control.


1992 ◽  
Vol 32 (4) ◽  
pp. 465 ◽  
Author(s):  
AD Doyle ◽  
RW Kingston

The effect of sowing rate (10-110 kg/ha) on the grain yield of barley (Hordeum vulgare L.) was determined from a total of 20 field experiments conducted in northern New South Wales from 1983 to 1986. Effects of sowing rate on kernel weight and grain protein percentage were also determined from 12 experiments conducted in 1985 and 1986. Two barley varieties were tested each year. In all years fallow plus winter rainfall was equal to or greater than average. Grain yield increased with higher sowing rates in most experiments, with the response curve reaching a plateau above 60-70 kg/ha. For 13 of the 40 variety x year combinations, grain yield fell at the highest sowing rates. Only in an experiment where lodging increased substantially with higher sowing rates was there a reduction in yield at a sowing rate of 60 kg/ha. The average sowing rate for which 5 kg grain was produced per kg of seed sown was 63 kg/ha. Grain protein percentage usually fell, and kernel weight invariably fell, with increasing sowing rate. Increasing sowing rates from the normal commercial rate of 35 kg/ha to a rate of 60 kg/ha typically increased grain yields by 100-400 kg/ha, decreased kernel weight by 0.4-2.0 mg, and decreased grain protein by up to 0.5 percentage points. In no case was the grain weight reduced to below malting specifications. It was concluded that sowing rates for barley in northern New South Wales should be increased to about 60 kg/ha.


1985 ◽  
Vol 25 (4) ◽  
pp. 922 ◽  
Author(s):  
D Lemerle ◽  
AR Leys ◽  
RB Hinkley ◽  
JA Fisher

Twelve spring wheat cultivars were tested in southern New South Wales for their tolerances to the recommended rates and three times the recommended rates of trifluralin, pendimethalin, tri-allate and chlorsulfuron. Recommended rates of these herbicides did not affect the emergence or grain yield of any cultivar. However, differences between cultivars in their tolerances to trifluralin, pendimethalin and chlorsulfuron at three times the recommended rate were identified. The extent of the reduction in emergence and/or grain yield varied with herbicide and season, and there was also a herbicidexseason interaction. Durati, Songlen and Tincurrin were the most susceptible cultivars to trifluralin, and Teal was the most tolerant. Yield losses from trifluralin were more severe in 1979 than in 1980 or 1981. The differential between cultivars treated with pendimethalin was smaller and more variable; Tincurrin was the only cultivar with a yield reduction in more than one season. Durati, Songlen and Shortim were the only cultivars affected by chlorsulfuron. A reduction in crop emergence of a cultivar treated with trifluralin or pendimethalin did not correlate consistently with any grain yield loss, and reductions in emergence were always greater than yield loss.


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.


1982 ◽  
Vol 22 (115) ◽  
pp. 62 ◽  
Author(s):  
DP Heenan ◽  
LG Lewin

Two experiments were done at the Yanco Agricultural Research Centre, New South Wales, in 1978-79 and 1979-80 to measure the response of long grain rice, cv. Inga, to rates of nitrogen applied at two different times. The highest yields were recorded when the nitrogen was applied at panicle initiation. Increasing the rate from 100 to 200 kg N/ha at panicle initiation had no effect on grain yield. When the nitrogen was applied earlier, just before permanent water, yields were highest at 50 kg N/ha and declined at the highest rates (150 and 200 kg N/ha). This negative yield response was mainly due to a drop in the percentage of filled florets, and occurred despite an increase in panicle number.


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