Effects of water deficit on yield of wheat and triticale

1980 ◽  
Vol 20 (106) ◽  
pp. 594 ◽  
Author(s):  
BG Sutton ◽  
EA Dubbelde
Keyword(s):  
Life Cycle ◽  
Water Deficit ◽  
New South ◽  
Water Status ◽  
Maximum Efficiency ◽  
Yield Response ◽  
Grain Production ◽  
Water Deficits ◽  
South Wales ◽  
Complete Life Cycle

The yield response of two commercial bread wheat cultivars and one triticale to water deficits imposed before anthesis, after anthesis, or during the complete life cycle was studied in a large bin (55l) experiment under rain shelters at Camden, New South Wales. Water status was managed by weekly water replacement to allow withdrawal to 25 and 0% remaining available soil water for the well-watered and deficient treatments, respectively. The three cereals performed similarly under continuously well-watered conditions (89.9, 91.1, and 100.7 g grain/bin) but under continuous water deficit the triticale produced significantly less than the bread wheats (31.2 cf 53.1 g grain/bin), respectively. The reason for this was the greatly reduced yield per plant from tillers in the triticale. Efficiency of water use over the complete life cycle for grain production was greater for the wheats than for the triticale (1.351 cf 0.954 g l-1, respectively), and maximum efficiency resulted from provision of adequate water before anthesis (an average of 1.310 g l-1 for treatments well watered before anthesis, cf an average of 1.130 g l-1 for those growing under water deficits). Post-anthesis water status had no significant effect on these values.

Superphosphate requirements of clover-ley farming. II.* The residual effects of topdressing

1977 ◽  
Vol 28 (2) ◽  
pp. 287 ◽  
Author(s):  
JF Ayres ◽  
JD McFarlane ◽  
GJ Osborne ◽  
EJ Corbin
Keyword(s):  
New South ◽  
Residual Effects ◽  
Moderate Increase ◽  
Grain Production ◽  
Grain Composition ◽  
Application Rates ◽  
South Wales ◽  
Ley Farming ◽  
Nitrogen Rates ◽  
Available Phosphate

The residual effects of topdressing the grazed clover-ley were evaluated at four sites in southern New South Wales. The significance (for the initial crop) of changes in soil fertility induced by topdressing were studied in crop experiments (five superphosphate drill rates x three nitrogen rates) immediately following the ley phase. Topdressing influenced the level of available phosphate at all sites: heavy applications induced a large increase in available phosphate, light applications induced a moderate increase, and omission of topdressing led to a slight decline. The rate of soil nitrogen accretion was affected by topdressing only at sites that were initially of medium soil phosphate status. Topdressing exerted residual effects on crop growth, grain yield, and grain composition; crops following topdressed leys showed little response to superphosphate drilled with the crop at sowing. By contrast, crops following untopdressed leys showed a consistent but low requirement for superphosphate; grain production was maximized at low application rates (< 100 kg superphosphate ha-1) and the (economic) optimal rate was usually in the range 30-60 kg superphosphate ha-1. For the initial crop, low drill application rates were apparently equivalent to large amounts of superphosphate applied by topdressing the ley. ___________________ *Part I, Aust. J. Agric. Res., 28: 269 (1977).

Control of post-emergence damping off in vetch with Dexon

1968 ◽  
Vol 8 (35) ◽  
pp. 767
Author(s):  
RN Allen
Keyword(s):  
Root Rot ◽  
New South ◽  
Yield Response ◽  
Damping Off ◽  
Plant Vigour ◽  
Basal Stem Rot ◽  
Stages Of Growth ◽  
South Wales ◽  
Yield Responses ◽  
The Cost

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.

Response of oats to seeding rate and nitrogen in the southern wheat belt of New South Wales

1974 ◽  
Vol 14 (67) ◽  
pp. 231 ◽  
Author(s):  
OR Southwood ◽  
F Mengersen ◽  
PJ Milham
Keyword(s):  
Nitrate Nitrogen ◽  
New South ◽  
Nitrogen Concentration ◽  
New South Wales ◽  
Fertilizer Application ◽  
Grazing Management ◽  
Grain Production ◽  
Seeding Rate ◽  
South Wales ◽  
Oat Cultivars

The effect of three rates of nitrogen (22.4, 44.8 and 89.6 kgNha-1 as anhydrous ammonia) and three seeding rates (67.3, 100.9, and 134.5 kg ha-1) on forage and grain production of two oat cultivars and on herbage nitrate-nitrogen concentration, was assessed at three sites in the southern New South Wales wheat belt. When oats were sown after two or three consecutive wheat crops nitrogen at 22.4 kg ha-1 was optimal for both forage and grain production. Herbage growth was best at the highest seeding rate (134.5 kg ha-1) but grain production was not influenced by seeding rate. Herbage growth of the oat cultivars Cooba and Coolabah was similar, but grain yields were higher from the latter. Herbage nitrate nitrogen increased linearly with nitrogen fertilizer application, levels that could be toxic to animals occurring in June. Cautious grazing management may be required during this period.

Response of Inga rice to nitrogen fertilizer rate and timing in New South Wales

1982 ◽  
Vol 22 (115) ◽  
pp. 62 ◽  
Author(s):  
DP Heenan ◽  
LG Lewin
Keyword(s):  
Nitrogen Fertilizer ◽  
Agricultural Research ◽  
New South ◽  
New South Wales ◽  
Research Centre ◽  
Yield Response ◽  
Fertilizer Rate ◽  
South Wales ◽  
Panicle Number ◽  
Nitrogen Fertilizer Rate

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.

Reproductive cycles, fat body cycles and socio-sexual behaviour in the Mallee dragon, Amphibolurus fordi (Lacertilia : Agamidae)

1978 ◽  
Vol 26 (4) ◽  
pp. 653 ◽  
Author(s):  
HG Cogger
Keyword(s):  
Life Cycle ◽  
Sex Ratio ◽  
Fat Body ◽  
New South ◽  
Reproductive Period ◽  
South Wales ◽  
Behavioural Types ◽  
Fat Bodies ◽  
Reproductive Cycles ◽  
Sexually Mature

A field study of the reproductive and fat cycles of the small agamid lizard Amphibolurus fordi was undertaken in two areas of mallee in central western New South Wales. The development of the gonads, including the histology of the testicular cycle, is described, together with correlated changes in the size of the inguinal fat bodies. The males emerge from winter torpor some 4-5 weeks before the females. The sex ratio approximates unity throughout the life cycle. Mating occurs from October to December; up to three clutches each of two or three eggs are laid in a season. The eggs hatch in 7-9 weeks after laying. The construction of the nesting chamber by the female is described. Apart from behaviour specifically geared to thermoregulation, two other behavioural types have been identified: male-female interactions involving only sexually mature individuals during the reproductive period, and non-sex-specific patterns which occur in both immature and mature individuals of either sex. Males are not territorial.

Short-term response of the nitrogen nutrition status of tall fescue and Italian ryegrass swards under water deficit

2005 ◽  
Vol 56 (11) ◽  
pp. 1269 ◽  
Author(s):  
Victoria Gonzalez-Dugo ◽  
Jean-Louis Durand ◽  
François Gastal ◽  
Catherine Picon-Cochard
Keyword(s):  
Water Deficit ◽  
Tall Fescue ◽  
Nitrogen Nutrition ◽  
Water Status ◽  
Italian Ryegrass ◽  
Nutrition Status ◽  
Grass Species ◽  
Simple Relationship ◽  
Water Deficits ◽  
N Concentration

Grasslands are rarely irrigated, thus water deficits often induce a reduction of the nitrogen nutrition index (NNI) during summer. This is measured using the ratio between the actual N concentration and the minimum N concentration required to achieve the maximum growth rate. NNI is derived from the standing biomass by a simple relationship. This paper details the results of a field experiment, combining 2 levels of irrigation with 2 levels of nitrogen fertilisation during the summer, on 2 commonly cultivated grass species in pure swards (tall fescue, Festuca arundinacea L., and Italian ryegrass, Lolium multiflorum). Plant water status, NNI, root length density (RLD), soil volumetric water content (θv), and mineral nitrogen concentration [N] were followed under water deficit and recovery. In both species, RLD was high (>6 cm/cm3) in the 0–0.25 m soil layer. Whereas the NNI of tall fescue responded strongly to its water status, Italian ryegrass was most often above optimal nitrogen nutrition because of its slow growth in that particular season and its higher superficial RLD. However, its NNI generally followed the θv closely, whereas tall fescue exhibited a delay in response of NNI upon rewatering, suggesting lasting effects of water deficits on the absorption capacity of roots in that species.

Effect of sowing time and nitrogen on rice cultivars of differing growth duration in New South Wales. 1. Yield and yield components

1994 ◽  
Vol 34 (7) ◽  
pp. 933 ◽  
Author(s):  
RF Reinke ◽  
LG Lewin ◽  
RL Williams
Keyword(s):  
Short Duration ◽  
New South ◽  
New South Wales ◽  
Yield Potential ◽  
High Yield ◽  
Yield Response ◽  
Growth Duration ◽  
Sowing Time ◽  
South Wales ◽  
Long Duration

New South Wales rice crops commonly take >180 days from sowing to harvest, and a reduction in crop duration is sought to increase the efficiency of rice production. The response of rice cultivars of differing growth duration to sowing time and N application was examined across 2 growing seasons. The highest yields were obtained at early sowing dates in each season. In season 2, the maximum yield of the short-duration cultivar M101 was not significantly different to the long-duration cultivars Calrose, Pelde, and M7, with yields >12 t/ha. However, yield of cv. M101 was significantly less than the long-duration cultivars at an early sowing date in season 1. Analysis of yield components did not clearly indicate the reason for reduced yield of the short duration cultivar. Damage by birds and mice before harvest, exacerbated by early maturity, is a possible cause.Later sowing reduced yields of all cultivars, with the short-duration cultivar-least affected. Optimum N application decreased with delay in sowing. At early sowings there was a positive yield response to increasing N, whereas at the latest sowings in each season the N response was negative for all cultivars. Where the yield response to applied N was positive, the yield component most associated with yield was the number of florets per unit area (r = 0.55). Where the yield response was negative, yield reductions were primarily caused by a reduction in the proportion of filled grains (r = 0.83). Minimum temperatures during the reproductive stage of each cultivar explained only a small amount of the variation in percentage of filled grain. Low minimum temperatures during the reproductive stage were not the sole cause of the reduction in proportion of filled grains of late-sown, high-N plots. The high yield potential of short-duration cultivars in The high yield potential of short-duration cultivars in the New South Wales rice-growing area is clearly demonstrated, as is the value of such cultivars where late sowing is unavoidable.

scholarly journals Vine water deficit : among the 3 applications of pressure chamber, stem water potential is the most sensitive indicator

OENO One ◽  
2000 ◽  
Vol 34 (4) ◽  
pp. 169
Author(s):  
Xavier Choné ◽  
Olivier Trégoat ◽  
Cornelis Van Leeuwen ◽  
Denis Dubourdieu
Keyword(s):  
Water Potential ◽  
Water Deficit ◽  
Leaf Water Potential ◽  
Water Status ◽  
Pressure Chamber ◽  
Leaf Water ◽  
Sensitive Indicator ◽  
Stem Water Potential ◽  
Water Deficits ◽  
Stem Water

<p style="text-align: justify;">Vine water status is an important factor in grape quality. High tannin and anthocyanin content in red grape berries are related to moderate vine water deficits. Hence, a simple and sensitive indicator is required to determine vine water status and especially water constraint. Pressure chamber allows a quick and easy to practice determination of water status in the vineyard. Three applications of pressure chamber are known: predawn leaf water potential (ΨB), leaf water potential (ΨF) and stem water potential (ΨT). Only ΨB and ΨF are widely used on vines. In this survey ΨB, ΨF, ΨT and transpiration flow were measured on mature leaves to determine non-irrigated vine water status in field grown vines during the growing season. In California as well as in France, stem Ψ was the most discriminating indicator for both moderate and severe water deficits. In every plot surveyed ΨT was much better correlated to leaf transpiration than ΨF. Moreover, ΨT revealed nascent water deficit earlier than ΨB did. Among the three application of pressure chamber, ΨT was the only one to indicate short term water deficit after a rainfall. Hence, ΨT appears to be a useful indicator for grapevine management in both non-irrigated and irrigated vineyards.</p>

scholarly journals Sharing Anxiety Is in the Driver’s Seat: Analyzing User Acceptance of Dynamic Ridepooling and Its Implications for Shared Autonomous Mobility

2021 ◽  
Vol 13 (14) ◽  
pp. 7828
Author(s):  
Sigma Dolins ◽  
Helena Strömberg ◽  
Yale Z. Wong ◽  
MariAnne Karlsson
Keyword(s):  
Focus Group ◽  
New South ◽  
Autonomous Vehicle ◽  
New South Wales ◽  
Maximum Efficiency ◽  
Community Culture ◽  
On Demand ◽  
South Wales ◽  
Autonomous Mobility ◽  
The Cost

As connected, electric, and autonomous vehicle (AV) services are developed for cities, the research is conclusive that the use of these services must be shared to achieve maximum efficiency. Yet, few agencies have prioritised designing an AV system that focuses on dynamic ridepooling, and there remains a gap in the understanding of what makes people willing to share their rides. However, in 2017, the Australian transport authority Transport for New South Wales launched over a dozen trials for on-demand, shared public transport, including AVs. In this paper, we investigate the user willingness-to-share, based on experiences from one of these trials. Four focus groups (19 participants in total) were held in New South Wales with active users of either the trialled on-demand dynamic ridepooling service (Keoride) or commercial ridepooling (UberPool). Through thematic analysis of the focus group conversations, the cost, comfort, convenience, safety, community culture, and trust in authority emerged as factors that influenced the willingness-to-share. When presented with driverless scenarios, the focus group participants had significant concerns about the unknown behaviour of their co-passengers, revealing sharing anxiety as a significant barrier to the adoption of shared AVs. This paper identifies previously disregarded factors that influence the adoption of AVs and dynamic ridepooling and offers insights on how potential users’ sharing anxiety can be mitigated.

A life cycle assessment approach to quantifying greenhouse gas emissions from land-use change for beef production in eastern Australia

2015 ◽  
Vol 37 (3) ◽  
pp. 273 ◽  
Author(s):  
Beverley K. Henry ◽  
D. Butler ◽  
S. G. Wiedemann
Keyword(s):  
Land Use ◽  
Life Cycle Assessment ◽  
Life Cycle ◽  
Land Use Change ◽  
New South ◽  
Ghg Emissions ◽  
Beef Production ◽  
South Wales ◽  
Eastern Australia ◽  
Direct Land Use Change

In life cycle assessment studies, greenhouse gas (GHG) emissions from direct land-use change have been estimated to make a significant contribution to the global warming potential of agricultural products. However, these estimates have a high uncertainty due to the complexity of data requirements and difficulty in attribution of land-use change. This paper presents estimates of GHG emissions from direct land-use change from native woodland to grazing land for two beef production regions in eastern Australia, which were the subject of a multi-impact life cycle assessment study for premium beef production. Spatially- and temporally consistent datasets were derived for areas of forest cover and biomass carbon stocks using published remotely sensed tree-cover data and regionally applicable allometric equations consistent with Australia’s national GHG inventory report. Standard life cycle assessment methodology was used to estimate GHG emissions and removals from direct land-use change attributed to beef production. For the northern-central New South Wales region of Australia estimates ranged from a net emission of 0.03 t CO2-e ha–1 year–1 to net removal of 0.12 t CO2-e ha–1 year–1 using low and high scenarios, respectively, for sequestration in regrowing forests. For the same period (1990–2010), the study region in southern-central Queensland was estimated to have net emissions from land-use change in the range of 0.45–0.25 t CO2-e ha–1 year–1. The difference between regions reflects continuation of higher rates of deforestation in Queensland until strict regulation in 2006 whereas native vegetation protection laws were introduced earlier in New South Wales. On the basis of liveweight produced at the farm-gate, emissions from direct land-use change for 1990–2010 were comparable in magnitude to those from other on-farm sources, which were dominated by enteric methane. However, calculation of land-use change impacts for the Queensland region for a period starting 2006, gave a range from net emissions of 0.11 t CO2-e ha–1 year–1 to net removals of 0.07 t CO2-e ha–1 year–1. This study demonstrated a method for deriving spatially- and temporally consistent datasets to improve estimates for direct land-use change impacts in life cycle assessment. It identified areas of uncertainty, including rates of sequestration in woody regrowth and impacts of land-use change on soil carbon stocks in grazed woodlands, but also showed the potential for direct land-use change to represent a net sink for GHG.

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