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.

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.

Nematode parasites of free-living rabbits, Oryctolagus cuniculus (L.) in eastern Australia

1966 ◽  
Vol 14 (2) ◽  
pp. 185 ◽  
Author(s):  
JD Dunsmore
Keyword(s):  
Breeding Season ◽  
New South ◽  
New South Wales ◽  
Nematode Parasites ◽  
South Central ◽  
South Wales ◽  
Eastern Australia ◽  
Regular Sampling ◽  
A Site ◽  
North Western

(1) Trichostrongylus retortaeformis (Zeder, 1800) in wild rabbits in Australia has been studied by more or less regular sampling of rabbit populations in four climatically different areas of eastern Australia. (2) In a semi-arid locality in north-western New South Wales, T. retortaeformis is rarely found; in a subtropical area of south-central Queensland it was found only in small numbers and many rabbits were apparently free of infection. In an area of the Riverina district of New South Wales most rabbits were infected but parasite numbers were rarely high. The highest levels of infection were recorded at a site in a subalpine area of New South Wales. (3) It was possible to build up a detailed picture of the dynamics of T. retortaeformis in rabbits throughout their lives at Snowy Plains, the subalpine site, in which breeding of rabbits is limited to a relatively few months each year. During their first 6-8 months of life (prior to their first breeding season) male and female rabbits carry moderate numbers of T. retortaeformis with the males carrying somewhat more parasites than the females. During the breeding season T. retortaeformis numbers in female rabbits increase very markedly (about tenfold) while numbers in male rabbits are decreasing to a low level (their lowest during the year). Following breeding, worm numbers in female rabbits drop quite rapidly while those in males increase to a similarly moderate level. Apparently a similar cycle of events occurs during each 12 months of a rabbit's life. (4) At Urana, in the Riverina plain region the cycle of events described above for Snowy Plains could not be seen, although T. retortaeformis was found in moderate numbers. This may have been due to infrequent sampling, lack of a defined rabbit breeding season, or some other factor.

Potassium deficiency and its management in a long-term rotation experiment in the south-western slopes New South Wales

2001 ◽  
Vol 41 (4) ◽  
pp. 497 ◽  
Author(s):  
G. D. Li ◽  
K. R. Helyar ◽  
M. K. Conyers ◽  
P. D. Cregan ◽  
B. R. Cullis ◽  
...  
Keyword(s):  
New South ◽  
New South Wales ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
The South ◽  
South Wales ◽  
Product Removal ◽  
Animal Excreta ◽  
K Concentration ◽  
A Site

Potassium (K) deficiency of wheat and pasture species was found at a site in the south-western slopes of New South Wales. The soil was a subnatric yellow sodosol. Subterranean clover (Trifolium subterraneum) was found to be less competitive for K in the soil compared with its associated grasses. Higher soil K concentrations were required to achieve the same subterranean clover K concentration in the grass–legume mixtures than in a subterranean clover monoculture. For wheat (Triticum aestivum) production, a soil exchangeable K (Kex ) below 0.25 cmol(+)/kg appeared to be deficient for the limed treatments, but there was no obvious critical value for either limed or unlimed treatments. The critical K exvalues for the grass –legume mixtures could not be simply specified because the values were affected by competition between species growing in swards of variable botanical composition. An annual rate of 20 kg K/ha for the pasture–crop rotations (50/50%) and 29 kg K/ha for the permanent pastures was estimated to be sufficient to replenish the K losses from product removal and animal excreta transferred to campsites at this trial site.

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.

ABORIGINAL LANGUAGES IN THE SOUTH CENTRAL COAST, NEW SOUTH WALES: FRESH DISCOVERIES

Oceania ◽  
1970 ◽  
Vol 41 (1) ◽  
pp. 20-27 ◽  
Author(s):  
A. Capell
Keyword(s):  
New South ◽  
New South Wales ◽  
The South ◽  
Central Coast ◽  
South Central ◽  
South Wales ◽  
Aboriginal Languages

Denudational history of the south‐central uplands of New South Wales

1981 ◽  
Vol 15 (2) ◽  
pp. 77-88 ◽  
Author(s):  
R. W. Young
Keyword(s):  
New South ◽  
New South Wales ◽  
The South ◽  
South Central ◽  
South Wales ◽  
History Of ◽  
History Of The South

Cycad killer, qu'est-ce que c'est? Dieback of Macrozamia communis on the south coast of New South Wales

2021 ◽  
Vol 69 (2) ◽  
pp. 102
Author(s):  
Keith L. McDougall ◽  
Penelope J. Gullan ◽  
Phil Craven ◽  
Genevieve T. Wright ◽  
Lyn G. Cook
Keyword(s):  
New South ◽  
New South Wales ◽  
Scale Insect ◽  
South Coast ◽  
Management Tool ◽  
Sufficient Evidence ◽  
Cultivated Plants ◽  
The South ◽  
Extreme Caution ◽  
South Wales

The association of an armoured scale insect (a diaspidid) with dieback of a population of a native cycad (Macrozamia communis L.A.S.Johnson) was investigated on the south coast of New South Wales. The diaspidid was found to be undescribed but morphologically similar to oleander scale – here we call it Aspidiotus cf. nerii. It is probably native to Australasia and its current known distribution is within Murramarang National Park (MNP). Aspidiotus cf. nerii has been abundant on symptomatic M. communis at MNP over at least the past decade and has spread to new parts of the park. In population studies of infested and uninfested areas we found that, although both areas had populations with reverse J curves showing dominance of seedlings, mortality of seedlings and caulescent plants was significantly higher in infested sites. Infested areas had been burnt less frequently than uninfested areas. Fire does not appear to eradicate the diaspidid but may reduce its effects enough for plants to recover. We recommend further research into the use of fire as a management tool. Although other factors may be contributing to the severity of the dieback, we suggest there is sufficient evidence for the diaspidid to be regarded as the primary cause of dieback in M. communis in MNP, regardless of its origin. Given the occurrence of similar diaspidids on cultivated plants in botanic gardens, translocation of threatened Macrozamia species using plants grown in nurseries should be undertaken with extreme caution.

Models of the distribution and abundance of ground-dwelling mammals in the eucalypt forests of north-eastern New South Wales in relation to environmental variables

2002 ◽  
Vol 29 (3) ◽  
pp. 313 ◽  
Author(s):  
P. C. Catling ◽  
R. J. Burt ◽  
R. I. Forrester
Keyword(s):  
Environmental Variables ◽  
New South ◽  
New South Wales ◽  
Slope Position ◽  
Slope Aspect ◽  
Significant Variable ◽  
South Wales ◽  
North Eastern ◽  
Eucalypt Forests ◽  
A Site

Statistical models are presented of the distribution and abundance of ground-dwelling mammals in eucalypt forests in relation to environmental variables within an area of approximately 24 000 km2 in north-eastern New South Wales. Environmental variables are defined as climatic or topographic variables that may be useful to map the distribution of fauna. The environmental variables examined were season, temperature, rainfall, elevation, lithology, steepness of slope, position on slope, aspect and landform profile. The probability of recording some species was higher in spring than autumn and many species were in highest abundance in areas of low temperature (high elevation). Although aspect was a significant variable in a number of models, no species was absent from any aspect category. Mid-slopes down to and including creeks and drainage lines were particularly important for many species, as were areas with flatter terrain. Although we have modelled environmental variables only there will no doubt be longer-term interactions between habitat and environmental variables. Fundamentally, environmental variables will determine the type of habitat present at a site, and the distribution of canopy communities, at least, can be predicted from environmental variables. However, other studies have shown for ground-dwelling mammals that environmental variables contribute little and it is the state of the habitat locally, and particularly the understorey, that determines their presence and abundance at a site. The results are discussed in relation to similar models using habitat variables and in relation to the use of such models in the management of ground-dwelling fauna in forests.

scholarly journals Acacia blayana, a new species from the South Coast of New South Wales (Acacia sect. Botrycephalae: Fabaceae)

Telopea ◽  
1990 ◽  
Vol 4 (1) ◽  
pp. 109-113 ◽  
Author(s):  
Mary Tindale ◽  
Arthur Court
Keyword(s):  
New Species ◽  
New South ◽  
New South Wales ◽  
South Coast ◽  
The South ◽  
South Wales ◽  
A New Species

Drosophilidae of Australia. 4. Mycodrosophila

1980 ◽  
Vol 28 (2) ◽  
pp. 261 ◽  
Author(s):  
IR Bock
Keyword(s):  
New South ◽  
East Asian ◽  
New South Wales ◽  
The South ◽  
Asian Species ◽  
South Wales ◽  
Eastern Australia ◽  
First Time

The Australian Mycodrosophila fauna comprises 21 species distributed in northern and eastern Australia to southern New South Wales. Only one species, M. argentifrons Malloch, is previously described from Australia; the south-east Asian species M. separata (de Meijere) is recorded for the first time. The remaining 19 species are new: adequate material has been available to permit the description and naming of 18 of them.

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