Predicting the development of photoperiod 'insensitive' winter wheats in south-central New South Wales

2003 ◽  
Vol 54 (3) ◽  
pp. 293 ◽  
Author(s):  
L. D. J. Penrose ◽  
N. A. Fettell ◽  
R. A. Richards ◽  
D. J. Carpenter
Keyword(s):  
New South ◽  
New South Wales ◽  
Initial Step ◽  
Regression Equations ◽  
Wheat Cultivars ◽  
Sowing Time ◽  
Field Development ◽  
South Central ◽  
South Wales ◽  
The Relationship

The aim of this study was to determine the effect of vernalisation on the field development of vernalisation responsive wheats in south-central New South Wales, and to develop equations with which to predict their timing of ear emergence in this region. To achieve this, a 'phasic development' approach was taken by considering relationships between temperature and photoperiod and the duration of the leaf, spikelet, and stem development phases in 3 photoperiod 'insensitive' vernalisation responsive wheat cultivars. The responsiveness to vernalisation of these cultivars covered much of the range that has been reported in wheat. This study was conducted at 3 sites and over 6 sowing times (17 field environments), covering the geographic and commercial range in sowing time for wheat grown in this region of Australia. An initial step in this study was to obtain measures of development duration that were independent of site and sowing date over our 17 field environments. Thus, appropriate photo-thermal units of time were sought using a photoperiod and vernalisation insensitive control wheat. The appropriate base temperatures and photoperiods we found for these photo-thermal units were not entirely consistent with those found in previous studies. Phase durations of our vernalisation responsive wheat cultivars were measured in these units.Vernalisation was found to be the predominant factor determining duration of both the leaf and spikelet phases in our vernalisation responsive wheat cultivars. The relationship we found between accumulated vernalisation and the duration of the leaf phase was similar to the relationship found in an earlier study in a controlled environment. This relationship differed from those currently used in 'phasic development' models for wheat. There appeared to be some latitude in the range of vernalising temperatures that could be used to estimate vernalisation in our field environments. Duration of the stem phase was strongly influenced by photoperiod, and showed greatest complexity of control, to the extent that site-specific effects could not be removed from equations predicting the duration of this phase.Simplified regression equations appeared to predict time of ear emergence reasonably well over the range of environments considered in our study, with the exception of a few cultivar × sowing time combinations for which wheat would not be commercially sown in the region. The ability to predict time of ear emergence may allow plant breeders to evaluate development controls that might extend the range of environments over which winter wheats may be commercially sown in south-central New South Wales.

Prediction of ear emergence in winter wheats grown at Temora, New South Wales

1997 ◽  
Vol 48 (4) ◽  
pp. 433 ◽  
Author(s):  
L. D. J. Penrose
Keyword(s):  
New South ◽  
New South Wales ◽  
Sowing Date ◽  
Thermal Time ◽  
Yield Potential ◽  
Regression Equations ◽  
Sowing Time ◽  
Frost Risk ◽  
South Wales

This study examined factors that determine ear emergence in winter wheats grown at Temora, New South Wales. Three development factors were considered: degree of winter habit, response to photoperiod, and intrinsic earliness. The effect of winter habit was first examined by using 3 pairs of related wheats that differed for spring–winter habit. Wheats were sown under irrigation from mid February to June, for up to 4 consecutive years. Ear emergence was recorded in days of the year for ease of field interpretation, and in photo-thermal time to measure delay in development. Winter habit was found to delay ear emergence throughout this sowing range. Ear emergence was then studied in 23 winter wheats that as a group encompassed a broad range for each of the 3 development factors, and these winter wheats were grouped on the basis of combinations of development factors. Differences in ear emergence between these groups guided the construction and testing of regression equations that described ear emergence as a function of sowing date and of the 3 development factors. Many combinations of factors were associated with the time of ear emergence (i.e. 1 October) at Temora that best optimises the balance between frost risk and yield potential. Combinations of development factors also influenced the flexibility of sowing time for winter wheats grown at Temora. These findings may assist the breeding of new winter wheats that can be sown over a longer period than current winter cultivars.

Comparison of winter habit and photoperiod sensitivity in delaying development in early-sown wheat at a site in New South Wales

1997 ◽  
Vol 37 (2) ◽  
pp. 181 ◽  
Author(s):  
L. D. J. Penrose ◽  
R. H. Martin
Keyword(s):  
New South ◽  
New South Wales ◽  
Photoperiod Sensitivity ◽  
Thermal Time ◽  
The South ◽  
Sowing Time ◽  
South Central ◽  
South Wales ◽  
A Site

Summary. This study compared 2 mechanisms that delay the development of early-sown wheat, winter habit and sensitivity to photoperiod. To conduct this study, ear emergence dates were recorded for serial sowings of 15 wheats over 4 consecutive years at Temora, New South Wales, comprising 36 sowings in total. Ear emergence was measured as day of the year, and in both thermal and photothermal time from sowing. The timing of ear emergence was first considered in 3 wheats that were insensitive to photoperiod and vernalisation. In contrast to thermal time, the duration from sowing to ear emergence did not vary with sowing time when measured in photothermal units. Such a measurement is essential for the study of mechanisms whose effect in delaying development is a function of sowing time. These results were obtained using a more simply calculated measure of photothermal time than has been previously reported. For early-sown wheat, winter habit was found to more strongly delay ear emergence and provide greater flexibility in sowing time than responsiveness to photoperiod. Our study provided evidence that winter habit is a more attractive method of delaying ear emergence in early-sown wheat than photoperiod sensitivity. This finding supports the continued breeding of winter wheats for early sowings in the south-central wheat belt of New South Wales.

Tolerances of wheat cultivars to pre-emergence herbicides

1985 ◽  
Vol 25 (4) ◽  
pp. 922 ◽  
Author(s):  
D Lemerle ◽  
AR Leys ◽  
RB Hinkley ◽  
JA Fisher
Keyword(s):  
Grain Yield ◽  
Spring Wheat ◽  
Yield Loss ◽  
New South ◽  
New South Wales ◽  
Yield Reduction ◽  
Wheat Cultivars ◽  
Yield Losses ◽  
South Wales

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.

Wheat for fodder and grain on the Northern Tablelands of New South Wales

1995 ◽  
Vol 35 (1) ◽  
pp. 93 ◽  
Author(s):  
RD FitzGerald ◽  
ML Curll ◽  
EW Heap
Keyword(s):  
Grain Yield ◽  
New South ◽  
New South Wales ◽  
Annual Rainfall ◽  
Sowing Time ◽  
Wheat Varieties ◽  
Dual Purpose ◽  
Grain Yields ◽  
High Rainfall ◽  
South Wales

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.

Bunch covers, leaf number and yield of bananas

1970 ◽  
Vol 10 (47) ◽  
pp. 802 ◽  
Author(s):  
DW Turner
Keyword(s):  
Water Relations ◽  
New South ◽  
New South Wales ◽  
Leaf Length ◽  
Leaf Number ◽  
South Wales ◽  
North Eastern ◽  
Number Of Leaves ◽  
The Relationship

The effects of plastic bunch covers and varying defoliation treatments on bunch weight were measured on Williams bananas at Alstonville in north-eastern New South Wales. Bunch covers did not significantly affect bunch weight. The number of leaves left on the plant at bunch emergence only reduced yield when less than four leaves were present. Leaf length duration was calculated and was positively related to bunch weight. Bunch covers did not alter the relationship between leaf number and yield. The rate of sucker growth and water relations within the plants were altered by defoliation treatments. Both of these effects were greatest when less than three leaves were left on the plant.

scholarly journals Screen-time, obesity, ageing and disability: findings from 91 266 participants in the 45 and Up Study

2010 ◽  
Vol 14 (1) ◽  
pp. 34-43 ◽  
Author(s):  
Emily Banks ◽  
Louisa Jorm ◽  
Kris Rogers ◽  
Mark Clements ◽  
Adrian Bauman
Keyword(s):  
Physical Activity ◽  
Screen Time ◽  
Vegetable Consumption ◽  
New South ◽  
New South Wales ◽  
Full Time ◽  
Obesity Prevalence ◽  
Cross Sectional ◽  
South Wales ◽  
The Relationship

AbstractObjectiveTo assess the relationship between obesity and sedentary behaviours, such as watching television or using a computer (‘screen-time’), and describe how this relationship varies between population subgroups.DesignCross-sectional analysis of the relationship between obesity (BMI ≥ 30 kg/m2) and screen-time, adjusted for age, sex, income and education and compared according to a range of personal characteristics.SettingNew South Wales, Australia.SubjectsA total of 91 266 men and women aged 45 years and above from the general population of New South Wales in 2006–2007 and providing self-reported information on height and weight and other factors.ResultsObesity prevalence was 21·4 %. Compared to individuals with <2 h of daily screen-time, the adjusted relative risks (RR) of obesity were 1·35 (95 % CI 1·26, 1·44), 1·70 (95 % CI 1·59, 1·82), 1·94 (95 % CI 1·81, 2·08) and 1·92 (95 % CI 1·80, 2·06) for 2–3, 4–5, 6–7 and ≥8 h, respectively. The increase in obesity with increasing screen-time was similar within categories of overall physical activity, but was attenuated in those in full-time paid work, compared to non-workers (P for interaction < 0·0001). Among non-workers, the overall obesity RR per 2 h increase in daily screen-time was 1·23 (95 % CI 1·21, 1·25) and was significantly elevated in all groups examined, ranging from 1·16 to 1·31 according to sex, level of age, education, income, smoking and fruit consumption. The RR did not differ significantly according to overall physical activity, region of residence and alcohol and vegetable consumption, but was substantially lower in disabled v. not-disabled individuals (P for interaction < 0·0001).ConclusionsObesity increases with increasing screen-time, independent of purposeful physical activity. This was observed in all population groups examined, although it is attenuated in full-time workers and disabled individuals.

Low nodulation and nitrogen fixation of mungbean reduce biomass and grain yields

2005 ◽  
Vol 45 (3) ◽  
pp. 269 ◽  
Author(s):  
D. F. Herridge ◽  
M. J. Robertson ◽  
B. Cocks ◽  
M. B. Peoples ◽  
J. F. Holland ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Grain Yield ◽  
New South ◽  
New South Wales ◽  
Soil Nitrate ◽  
Grain Yields ◽  
South Wales ◽  
Negative Effect ◽  
On Farm ◽  
The Relationship

Apparent nodulation failures and associated low grain yields have been reported for commercial mungbean (Vigna radiata) crops in southern Queensland and northern New South Wales. We therefore conducted on-farm surveys of 40 commercial mungbean crops in the region in which symbiotic traits, i.e. nodulation and nitrogen fixation, and biomass and grain yield were monitored. Effects of bradyrhizobial inoculation and inoculation methods on mungbean and soybean (Glycine max) symbiosis and yield were determined in experiments at 3 sites in northern New South Wales. Thirty-four of the 35 mungbean crops assessed for nodulation were nodulated. The relationship between soil nitrate to a depth of 90 cm at sowing and mungbean nodulation was not significant. However, at low-to-moderate soil nitrate levels (<100 kg N/ha), the mean nodule score was 1.6, compared with 0.5 at high (>100 kg N/ha) soil nitrate levels. Soil nitrate had a negative effect on the percentage of mungbean nitrogen derived from nitrogen fixation (%Ndfa). Mean %Ndfa values for soil nitrate levels <50, >50–100 and >100 kg N/ha were 35, 22 and 19% respectively. Grain yields of the surveyed mungbean crops varied from 0.3 to 2.1 t/ha, and were correlated with shoot dry matter. Grain yield was not significantly correlated either with sowing soil nitrate, nodule score or %Ndfa. In the inoculation experiments, mungbean did not nodulate as well as soybean, producing about one-third the number of nodules. Both species responded to inoculation with increased nodulation, although data from one of the sites suggested that responses during early growth of mungbean were not maintained during pod-fill. Effects of inoculation on mungbean %Ndfa were marginal. Average increases were 9%, based on natural 15N abundance, and 6%, based on the ureide method. Soybean %Ndfa, on the other hand, responded strongly to inoculation, with increases of 56 (15N) and 77% (ureide). Inoculation increased mungbean crop N by an average of 10% and grain yield by 6%, compared with responses to fertiliser nitrogen of 31% (crop N) and 10% (grain yield). For soybean, inoculation increased crop nitrogen by 43% and grain yield by 7%, similar to responses to fertiliser nitrogen of 45 (crop N) and 5% (grain yield). These results suggest that inoculated mungbean was N-limited and that inoculation of mungbean using current technology may be somewhat ineffectual. We concluded that low nodulation and nitrogen fixation of commercial mungbean most likely results from the suppressive effects of nitrate and/or insufficient numbers of bradyrhizobia in the soil. When low symbiosis and low soil nitrate are combined, N is likely to limit crop growth, and potentially grain yield. Suggested strategies for improving mungbean nodulation and nitrogen fixation in the northern grains belt include selection of more symbiotically competent plant and bradyrhizobial genotypes and more effective utilisation of established soil populations of mungbean bradyrhizobia.

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