bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of plant density on the winter production of annual clovers grown in monocultures
Authors: Evans P. M. , Walton S. , Riffkin P. A. , Kearney G. A.
Published: September 2002

The small-seeded annual clovers, balansa and Persian, are often assumed to be
poor winter producers. Their small seed size, of about 1 mg or less, and poor
regeneration, possibly due to inappropriate grazing management in many
instances, contributes to this perception. To test the hypothesis that early
growth of these clovers is determined by the weight of germinating seed, as it
is in subterranean clover, an experiment with 2 cultivars of subterranean
clover, Leura and Trikkala, 2 cultivars of balansa clover, Paradana and Bolta,
and 1 of Persian clover, Nitro Plus, was established in the field at Hamilton,
western Victoria, at 6 sowing densities. The winter production at 2 additional
sites, Lake Bolac and Streatham, in their third and second and third seasons,
respectively, was also examined. Plant density varied from 30 to 37000
plants/m2 across sites and species.
With equal weight of germinating seed per unit area at sowing, balansa and
Persian clovers produced more herbage in winter than did the 2 subterranean
clover cultivars Leura and Trikkala (P<0.05). Even
though there was high correlation between seed weight and seedling weight
across all species shortly after emergence
(r2 = 0.99), by harvest
time no differences in plant weight existed between any treatments growing at
the same plant density. From this we conclude the following: (i) for the same
weight of germinable seed per unit area, balansa and Persian clovers produced
more dry weight per hectare than subterranean clover, because they had higher
plant densities; (ii) there were no differences in dry matter production per
hectare between species growing at similar plant densities by harvest time at
the end of winter; (iii) it appeared that in winter the small-seeded species
exhibited a higher relative growth rate than the 2 subterranean clovers.
Germination, emergence, growth, ecotypes and control of Carex appressa R. Br. (tussock sedge)
Authors: Campbell M. H. , Nicol H. I.
Published: September 2002

Germination of seeds of Carex appressa R.Br. (tussock
sedge) collected in 1989 and 1990 from Bigga, Boorowa and Kerrs Creek, New
South Wales, Australia, stored in a laboratory and germinated annually in
45-day tests, declined from an initial 75–90% in year 1 to
0.5–14% in years 10 and 11. The germination of seeds collected
from Bigga and Boorowa in 1991 declined from 90–91% in year 1 to
12–61% in year 9. This decline was best described by generalised
logistic curves (Bigga) and exponential curves (Boorowa). Most seeds that
failed to germinate were shown to be non-viable by the tetrazolium test. Rate
of germination declined with seed age, so that days for 50% of final
germination percentage increased from 8 days for 1 year-old seeds to >40
days for 11-year-old seeds. Of 8–11-year-old seeds that germinated
between days 45 and 140, 62–70% had deformed seedlings.
Germination of seeds buried in the soil for 0.5–2.7 years was lower than
that of the same seed stored in the laboratory. Germination of seeds buried at
5 mm (19%) was lower than that of the same seeds buried at 40 mm
(50%). Almost all the decline in germination occurred in the first 6
months of burial. Increased depth of sowing reduced emergence (%),
height of the shoot and length of the primary root and increased the time
taken for emergence and length of the mesocotyl. The maximum depth
C. appressa seedlings could emerge from was 44 mm.
Growth of C. appressa seedlings was slower than that of
pasture species and responded to nitrogen and nitrogen + phosphorus
and/or sulfur but not to phosphorus and/or sulfur. Differences were
recorded in the morphology of plants grown from seeds collected from various
locations and grown in the 1 environment at Orange, New South Wales. Control
of C. appressa was achieved by draining, slashing and
removing litter, applying glyphosate, surface-sowing pasture species and
topdressing with superphosphate. Five years after sowing, the foliage cover of
legumes and grasses on the best treatment was 71% and that of
C. appressa 2%, a substantial decline from the
original 81% infestation. The best technique for control of
C. appressa on infested creek flats suitable for pasture
production would be to drain, plough and bury seeds below 44 mm and then sow
pastures with superphosphate. Where ploughing is not possible, drainage,
burning to remove foliage, spraying with glyphosate and surface-sowing
pastures with superphosphate would be successful. In both situations,
long-term control can be achieved by heavy grazing for short periods only when
the soil is firm and removing re-infesting plants by annual spot spraying.
Detection of Prunus necrotic ringspot virus in almond: effect of sampling time on the efficiency of serological and biological indexing methodologies
Authors: Bertozzi T. , Alberts E. , Sedgley M.
Published: September 2002

The reliability of enzyme-linked immunosorbent assay (ELISA) and indexing
methodologies for the detection of Prunus necrotic
ringspot virus (PNRSV) in almond was assessed under local conditions. Thirteen
field-grown almond trees were sampled fortnightly throughout the growing
season. Petal and leaf homogenates were used for ELISA and to inoculate
herbaceous indicator species, while buds collected from October onwards were
budded to woody indicators. ELISA reliably detected PNRSV in petals and young
leaves from bud-break until the cessation of stem elongation. While herbaceous
indexing was not as reliable as ELISA, woody indicators could differentiate
positive from negative samples reliably throughout the testing period.
However, for mass screening of foundation plantings, nursery stock and elite
germplasm, woody indexing is too costly and slow to give results. The use of
ELISA can overcome these limitations but the timing of sample collection is
critical. Petal or leaf tissue collected early in the season will yield the
most reliable results.
Assessment and selection of new hybrids from the Australian cashew breeding program
Authors: Blaikie S. J. , O'Farrell P. J. , Chacko E. K. , Müller W. J. , Wei X. , Steele Scott N. , Sykes S. R.
Published: September 2002

Cashew (Anacardium occidentale L.) is an emerging crop suited to tropical regions of Australia. To be viable on world markets, Australian cashews must be more productive and of higher quality than competing products. Since these characteristics are not exhibited consistently by existing varieties, an improvement program was initiated. This paper reports on the evaluation of 2 sets of hybrids produced in 1991 and 1992, which were planted on commercial cashew orchards in the Northern Territory and Queensland and were assessed in terms of yield and quality during 1998 and 1999.
Mortality of Prosopis pallida (mesquite) following burning
Authors: Campbell S. D. , Setter C. L.
Published: September 2002

A 2-year study investigated fire as a potential control technique for the invasive woody weed Prosopis pallida (Willd.) K�nth by comparing changes in plant density and stem basal area between burnt and unburnt plots. Three months after burning only 8% of the original 1760 plants per hectare remained alive, compared with 100% survival in control plots. Over the ensuing 21 months, a further 2.5 and 21% of the original plants died in burnt and control plots, respectively, and 90% of control plants that died were young plants (less than 0.5 m in height). Burning also reduced recruitment of P. pallida during the 2 post-fire years, although very few seedlings that emerged remained alive at the end of the study period in either control or burnt plots. Two years after treatments were applied, the population of P. pallida in control and burnt plots had decreased by 7 and 93% of the initial populations, respectively. Similarly, the total stem basal area of P. pallida in burnt plots after 2 years was 0.9 m2/ha, 93% less than that in the unburnt controls. Seedling recruitment had a minimum impact on stem basal area in both control and burnt plots, contributing less than 0.005%. Subsequent control measures will be necessary to treat any plants not killed by fire and any new seedlings.
Influence of panicle fragment size on ant seed-harvesting and seedling recruitment in Phalaris aquatica
Authors: Kelman W. M. , Lodge G. M. , Culvenor R. A.
Published: September 2002

Successful seedling recruitment events in sparse stands of the grass Phalaris aquatica (phalaris) are rare. A major contributing factor to this situation is the seed-harvesting activity of ants. In recently developed cultivars of phalaris, the seed is retained within the glumes of the floret and is shed in a seed-retaining panicle fragment. We tested the hypothesis that seed contained in panicle fragments was less likely to be harvested by ants than naked seed and that this would be reflected in increased seedling recruitment. Observations of ant seed-harvesting activity and records of seedling recruitment following dispersal of seed and panicle fragments onto field plots were made at Canberra, Australian Capital Territory, and Tamworth, New South Wales, over 2 years. In the second year, the effects of 2 pasture renovation treatments (sheep-grazing and shallow-discing) on seedling recruitment from seed and panicle fragments were examined. Averaged over the 2 localities, 4% of large-sized (>10�florets), 13% of medium-sized (5-10 florets) and 27% of the small-sized (2 or 3 florets) panicle fragments were harvested in a 24 h period by ants (mainly Pheidole spp.), compared with 83% of the naked phalaris seed. The effects of panicle fragment size on recruitment were variable depending on site in the first year and the interaction of site and renovation treatments in the second year, but contrary to expectation, recruitment often was not higher in panicle fragment treatments than in seeded treatments. Seedling recruitment at Canberra (a hardsetting sandy loam) was lower (22 plants/m2 from naked seed and 15 plants/m2 from seed in panicle fragments) because of the competition from existing vegetation and germination of subterranean clover from the seedbank, than at Tamworth (a self-mulching red chromosol; 179 plants/m2 from naked seed and 118 plants/m2 from seed in panicle fragments), where seedling recruitment was also significantly increased by the sheep-grazing renovation treatment. At Tamworth, a larger seedbank was recovered from plots of oversown panicle fragments compared with plots oversown with naked phalaris seed. This suggested that protection of seeds in panicle fragments over the summer months on the Tablelands of New South Wales would increase the time over which phalaris seeds are available for recruitment. Further work is needed to test seedling recruitment in panicle shattering v. non-shattering phalaris populations and to define the conditions under which the seedbank contained in the panicle fragments can be exploited to improve stand persistence.
Temperate Pasture Sustainability Key Program: an overview
Authors: Mason W. K. , Kay G.
Published: September 2002

This special edition of the
Australian Journal of Experimental Agriculture presents
papers from work undertaken as part of the Temperate Pasture Sustainability
Key Program (TPSKP; see Fig. 1), and presented at a workshop in Sydney in
November 1997.
TPSKP was initiated by Meat and Livestock Australia (MLA). The Land and Water
Resources Research and Development Corporation, the International Wool
Secretariat and the Murray Darling Basin Commission were joint funders of some
of the individual projects.
Most projects were carried out on private properties, and many had producer
groups associated with the sites to provide input into treatment selections as
well as management guidance and support. This substantial producer input was
provided free to the program.
The success of TPSKP relied heavily on physical and financial support from
State departments of agriculture and conservation, CSIRO and universities, and
also on the enthusiasm of these groups to work collaboratively across the 4
south-eastern states. One of the key results of this cooperation was the
development of a set of experimental protocols so that measurements taken
anywhere in TPSKP could be directly compared.
TPSKP aimed to develop the principles for manipulating pasture composition to
make grazing systems more productive and sustainable. The program priorities
were to: (i) determine by survey the attitudes of producers to grazing
management and identify the characteristics of those producers most likely to
adopt the program results; (ii) demonstrate by June 1996 that potentially
responsive perennial grass-based pastures could be upgraded using grazing
management to become a ‘desirable’ pasture for animal production
and sustainability; (iii) demonstrate by June 1996 that newly sown perennial
grass-based pastures could be maintained in a desirable condition using
grazing management; (iv) determine the critical factors responsible for the
capacity of perennial grasses to persist, respond to drought, and ameliorate
land degradation; (v) develop producers’ skills in pasture species
identification, pasture and animal assessment, and feed budgeting, both to
enhance their existing management, and to ‘prime’ them for the
outputs from TPSKP; (vi) to demonstrate (in phase 2) that improvements in
pasture composition and grazing management can have both economic and
environmental benefits.
Quantifying the sustainability of grazed pastures on the Northern Tablelands of New South Wales
Authors: Scott J. M. , Hutchinson K. J. , King K. , Chen W. , McLeod M. , Blair G. J. , White A. , Wilkinson D. , Lefroy R. D. B. , Cresswell H. , Daniel H. , Harris C. , MacLeod D. A. , Blair N. , Chamberlain G.
Published: September 2002

An experiment was conducted to examine the
effect of deep-rooted perennial grasses on the water and nitrogen economy of 3
mature pasture communities with different botanical compositions but the same
fertiliser history. One pasture was dominated by volunteer naturalised pasture
grasses (Eleusine tristachya and
Danthonia spp.) (termed ‘degraded’), another
was phalaris (Phalaris aquatica) dominant (phalaris),
and a third was dominated by phalaris into which white clover
(Trifolium repens) had been recently sown
(phalaris–white clover).
Two replicates of each pasture type were grazed continuously over 4 years with
young weaner sheep changed each year. Measurements of hydrology, nutrient
cycling, botanical composition and animal production were made in order to
quantify the sustainability characteristics of each of the pasture types.
Data are summarised as absolute measures at various points in time and also as
trends over time. The ranking of standardised treatment measures was then
summed to provide an index of sustainability with or without a weighting
assumed to be representative of the relative importance of various layers of
sustainability viewed from the perspective of a hypothetical
‘typical’ grazier. The results show that the phalaris–white
clover treatment was substantially more sustainable, in both ecological and
economic terms, than either of the other treatments. The unweighted index for
the phalaris–white clover pasture was 3.61 compared to 2.08 and 1.98 for
the phalaris and ‘degraded’ pastures, respectively.
Producer perceptions of pasture decline and grazing management
Authors: Reeve I. J. , Kaine G. , Lees J. W. , Barclay E.
Published: September 2002

The improvement of the sustainability of meat
and wool production in the high rainfall temperate zone of Australia depends,
in part, on the extension of grazing management approaches to maintain a
desirable species composition. A survey of producers in this zone was
undertaken to describe some of the factors relevant to the adoption of grazing
management practices. It was found that there is widespread concern among
producers about pasture decline. Weeds and weed control appear to play an
important role in producers’ perceptions of the problem and appropriate
remedial action. Producers do not seem to doubt that grazing management might
be used to maintain a desirable species composition, but substantial numbers
believe that other influences, such as drought, may over-ride the capacity of
grazing management to maintain a desirable species composition. The
implications of these findings for the extension of grazing management
practices to producers, are discussed.
Pre-season soil establishment of legume inoculant rhizobia is not effective for the nodulation of lupin and faba bean crops in acidic soils
Authors: Evans J. , Eberbach P. , Luckett D. , Cormack S.
Published: September 2002

In soils with a resident population of symbiotically effective rhizobia in
sufficient number that legume inoculation is not a requirement for successful
legume cropping, greater flexibility may be exercised in the use of legume
seed dressings that are toxic to rhizobia. Inoculating crops antecedent to
legume crops has been suggested as a method for pre-establishing effective
inoculant rhizobia in soil. The extent to which this strategy
(pre-inoculation) would remove the need for inoculating legume seed
(conventional inoculation) was tested for Bradyrhizobium
sp. (Lupinus) and
Rhizobium leguminosarum bv. viciae
with crops of lupin (Lupinus angustifolius) and faba
bean (Vicia faba), respectively.
In the glasshouse, in pasteurised sand and red kandosol, the numbers of
B. sp. (Lupinus) in the
rhizospheres of wheat (Triticum aestivum), canola
(Brassica campestris) and clover
(Trifolium subterraneum) increased 300–10000-fold
over a 14-week period, reaching numbers similar to that achieved on
L. angustifolius. These increases were not greatly
affected by chemical seed dressings commonly applied to the crops: on wheat,
Vincit C and Baytan C; on canola and subterranean clover, Lemat. In the sandy
soil, the nodulation of lupin following pre-establishment of rhizobia, drying
and mixing of soil, was not improved by conventional inoculation; in the red
kandosol nodulation was increased only marginally by conventional inoculation.
The results with the glasshouse pot trials warranted further investigation in
the field.
Under field conditions, when B. sp.
(Lupinus) was pre-established with wheat, on a red
kandosol in south-western New South Wales, the number of these bacteria
surviving in the dry soil at the end of the wheat phase was much lower than in
the glasshouse study. In the following season, the nodulation of lupin sown
without inoculant, and dependent only on pre-established rhizobia, was
significantly reduced, as compared with that on conventionally inoculated
lupin. An exception occurred where the lupin was dry-sown 3 weeks before rain,
in which case nodulation was comparatively poor even with conventional
inoculation. Reduced nodulation was generally consistent with initially fewer
rhizobia in the lupin rhizosphere. However, the numbers of rhizobia were
eventually similar to those found with conventional inoculation. In the third
year, in autumn, B. sp. (Lupinus)
was abundant in the soil in all treatments and there were no differences in
lupin nodulation between treatments.
Similarly, introducing R. leguminosarum bv.
viciae on wheat, in an acidic red kandosol in
south-western New South Wales, failed to provide as much nodulation of faba
bean as was achieved with conventional inoculation. The maximal dry matter of
the bean crop was also significantly lower with pre-inoculation as compared to
conventional inoculation.
Nitrogen and environmental factors influencing macadamia quality
Authors: Stephenson R. A. , Gallagher E. C. , Doogan V. J. , Mayer D. G.
Published: September 2002

Applications of nitrogen fertiliser in macadamia orchards remain high, despite
indications that optimum yields and quality are obtained at a lower rate. This
6-year study examined the effect on quality of 230, 690 and 1150 g
nitrogen/tree . year, applied in April (floral initiation), in April and
June (inflorescence development), in April, June and November (rapid nut
growth and premature nut drop), in April, June, November and January (nut
maturation/oil accumulation) or monthly. Higher rates of nitrogen
increased kernel recovery by 1% in 5 years out of 6. In 1 year only, 4
or more split applications of the medium and high rates of nitrogen increased
kernel recovery by up to 1.6%. These increases were insufficient to
compensate for depressed yields (17% lower) at high nitrogen. In good
years, when yields were above average, kernel recovery tended to be high and
in years with poor yields, kernel recovery tended to be low except when nuts
were small. Moderate summer—early autumn rainfall of about 100
mm/month was associated with high kernel recovery whereas very heavy
rainfall (>200 mm/month) during this period was detrimental.
The percentage of first grade kernels was influenced most by season but was
negatively correlated with the rate of nitrogen. Impurities, including
immature, deformed, mouldy and insect-damaged kernels, were lowest at low
rates of nitrogen and highest during wet harvest seasons.
Time of nitrogen application had no significant effect on yield, kernel
recovery, the percentage of first-grade kernels or impurities. For sustained
high yield and quality, 355 g nitrogen, or 0.8 kg urea/tree.year, applied
in April—June is indicated. Agronomic and economic advantages of
reducing rates of nitrogen applied to macadamia orchards are enhanced by
increasingly important environmental considerations.
Multiple regression analyses indicated that the rate, strategy and timing of
nitrogen application, rainfall, temperature, flushing and litterfall were
correlated with kernel recovery and first-grade kernels but more work is
needed to elucidate the significance of these factors.
Extension theory and practice: a review
Authors: Black A. W.
Published: September 2002

This paper examines strengths and limitations of four major strategies or
models in agricultural extension: linear ‘top-down’ transfer of
technology; participatory ‘bottom-up’ approaches; one-to-one
advice or information exchange; and formal or structured education and
training. The main conclusion is that no single model or strategy is likely to
be sufficient by itself. Despite criticisms of linear technology transfer
models, there is still a need for access to reliable scientific information,
just as there is a need to provide for active participation by farmers in
research and development processes. One-to-one exchange of information and
advice, whether from farmer to farmer or from professional adviser to farmer
(and vice versa), will continue to be important. So too will be the lifting of
levels of formal education and training among farmers. New information
technologies will facilitate some forms of education, training and information
exchange, but will need to be supplemented by other extension strategies.
Evaluation of tree establishment treatments on saline seeps near Wellington and Young in New South Wales
Authors: Marcar N. E. , Hossain A. K. M. A. , Crawford D. F. , Nicholson A. T.
Published: September 2002

The success of tree establishment on both
saline and non-saline sites is dependent on the use of appropriate pre- and
post-planting procedures. The 4 trials reported here on 2 dryland saline
sites, near Wellington and Young in New South Wales, deal with the individual
and combined effects of mulch, fertiliser, tree guards and pre-conditioning
with salt and waterlogging, alone and in combination, on survival and growth
of Acacia stenophylla,
Atriplex nummularia,
Casuarina cunninghamiana,
Eucalyptus camaldulensis and
Melaleuca halmaturorum. Each trial included 1 or more of
these species. Soil salinity was assessed at the plot level using a hand-held
electromagnetic induction device (EM38).
Treatments had variable effects, depending on species, site, experiment and
treatment combinations. Mulch application significantly improved height in 2
trials and, in combination with plastic guard and fertiliser, produced the
best results. Treatments generally increased basal stem diameter or stem
diameter at breast height, and crown volume, but the differences were usually
not statistically significant. The combined effect of mulch, fertiliser and
plastic guard on growth was usually greater than any single treatment.
Productivity and pasture intake of defaunated crossbred sheep flocks
Authors: Hegarty R. S. , Shands C. , Harris C. , Nolan J. V.
Published: September 2002

From a flock of pregnant crossbred ewes, 63 were established as protozoa-free
by treatment with alkanate 3SL3 and 64 ewes were maintained as controls. The
controls included 20 ewes, which had been defaunated and subsequently
re-inoculated with protozoa. After lambing, both flocks were grazed in a
6-paddock rotation until weaning at 20 weeks of age. Defaunated ewes were
heavier than control ewes throughout lactation and had a higher urinary
allantoin concentration than the control ewes. Intake and apparent
digestibility of pasture dry matter by ewes did not differ between groups
although these estimates were confounded by differences in pasture composition
between the paddocks used. Both groups selected a diet with digestibility
approximately 10% units higher than the bulk digestibility of pasture
on offer. Control ewes selected a higher proportion of white clover in their
diet than was available in the pasture (24% v.
2%) but defaunated ewes did not exhibit preferential selection for
clover. Lambs from defaunated ewes were heavier at birth, remained heavier
until weaning and grew more wool than lambs from control ewes. Contamination
of fauna-free ewes and lambs with protozoa was first observed at weaning and
protozoa were detected in 41 out of 60 lambs, 4 weeks after contamination was
first detected. Study of defaunated ewes returned to a flock of untreated ewes
confirmed rapid spread of contamination into defaunated ewes with small
entodiniomorph protozoa establishing first.
Growth and yield of 3 hybrid papayas (Carica papaya L.) under mulched and bare ground conditions
Authors: Elder R. J. , Macleod W. N. B. , Reid D. J. , Gillespie R. L.
Published: September 2002

At Yarwun (151.3˚E, 23.75˚S), Australia, papaya Hybrid 29 yielded
twice as much fruit as Hybrid 11 and 30% more than Hybrid 13. The plots
mulched with coarse grass hay yielded 50% more fruit than the plots
with bare ground. The highest yielding treatment, Hybrid 29 + mulch,
averaged the equivalent of 81 t/ha.year over the 16.5-month harvest
period. The yields were achieved in spite of inadequate water supply due to
drought and the loss of 877 plants from 1441 plant positions (4 plants per
position) due to the 3 phytoplasma diseases; dieback, yellow crinkle and
mosaic.
Hybrid 29 produced higher yields than the other hybrids by flowering early on
shorter plants with thicker stems and setting more fruit that commenced lower
down on the stem. Hybrid 13 was intermediate in size and the amount of fruit
setting between Hybrid 29 and Hybrid 11 but was the slowest to flower and set
fruit. Hybrid 11 had the thinnest and tallest stems, flowered at an
intermediate time between the other 2 hybrids and produced fewer flowers and
fruit resulting in the lowest yield.
Mulching increased stem height and thickness, promoted earlier flowering and
increased fruit set, yield and average fruit weight
Nodulation and growth of pasture legumes with naturalised soil rhizobia. 1. Annual Medicago spp.
Authors: Ballard R. A. , Charman N.
Published: September 2002

The ability of 11 species of annual medics
(Medicago doliata, M. laciniata,
M. littoralis, M. minima,
M. orbicularis, M. polymorpha,
M. praecox, M. rigidula,
M. rigiduloides, M. tornata and
M. truncatula) to nodulate and fix nitrogen with
naturalised rhizobia from 28 South Australian soils was assessed. The number
of rhizobia in the soils was estimated. Medic shoot dry matter production and
nodulation were measured, after inoculation of medic seedlings with a soil
suspension, in 2 glasshouse experiments.
The number of medic rhizobia ranged from 0.4 10 2 to 1.5
10 6 per gram soil.
Medicago laciniata was the only medic species tested
which was not consistently nodulated by the soil rhizobia. While all the other
species formed nodules, they varied widely in their ability to form an
effective symbiosis. Symbiotic performance (which indicates how much growth
the medic line achieved, when compared to an effective inoculation treatment)
of the medic species ranged from 3%
(M. rigiduloides) to 67%
(M. praecox). Herald
(M. littoralis) achieved a symbiotic performance of
49% and it was estimated that this would be insufficient to meet the
nitrogen requirements of a Herald-based pasture during early growth. The
symbiotic performance of Santiago (M. polymorpha) was
low (17%) and erratic (from –6 to 72%). The ability of the
rhizobia to form an effective symbiosis varied widely also between soil
regions. For example, the rhizobia in Riverland soils resulted in only
31% of the shoot dry matter of those in Eyre Peninsula soils, in
association with M. polymorpha.
There are significant opportunities to improve the symbiotic performance of a
number of the species of annual medics examined in this study. Options to
improve the effectiveness of the symbiosis of medics with naturalised soil
rhizobia are discussed.
Cultivar, sowing date and plant density studies of fibre hemp (Cannabis sativa L.) in Tasmania
Authors: Lisson S. N. , Mendham N. J.
Published: September 2002

This paper reports on a 3-year agronomic study into fibre hemp
(Cannabis sativa L.) conducted in Tasmania, Australia.
The performance of selected hemp cultivars, and the responses to sowing date
and plant density were investigated as part of a broad feasibility study to
assess the potential of fibre hemp and flax
(Linum usitatissimum L.) as sources of fibre for the
Australian newsprint industry.
Trials were conducted at separate sites in north-west and south-east Tasmania.
Nine cultivars from the Ukraine, Hungary and France were examined in 2
separate trials. The Hungarian cultivars, Kompolti and Unico B, and the French
cultivar Futura 77 had the highest single plot dry stem yields (up to 1500
g/m 2 ) and bark proportions (up to 40%). All
the cultivars flowered toward the end of January, suggesting that the growing
season in Tasmania could accommodate much later flowering and potentially
higher yielding genotypes. Levels of the psychoactive agent,
delta-9-tetrahydrocannabinol were consistently below the legal maximum of
0.35% (dry weight basis).
Three sowing date trials were conducted across 2 seasons incorporating dates
between mid September and mid November and a single autumn planting at the end
of May. Interactions with cultivar and planting density were also considered.
Stem and bark yield declined with delays in sowing after early–mid
October in response to a decline in calendar days and thermal time from sowing
to flowering. The response was most pronounced in sowings of Kompolti, which
flowered within a short period and differed more substantially in durations to
flowering. Earlier sowings were limited by premature flowering in response to
shorter daylengths and by poor drainage at one of the 2 trial sites. The
success of early sowings in Tasmania would appear to depend on finding
cultivars less sensitive tophotoperiod, and cultivation on well drained sites.
A further trial was conducted to investigate the influence of plant density on
hemp yields. Treatments included densities from 50 to 300 plants/m
2 . Plant density declined with crop growth across all
treatments and was most pronounced for populations of 200 and 300 plants/m
2 . Final harvest stem yield responded in a parabolic
manner to plant density, with maximum yields at about 110 plants/m
2 . Differences in the percentage of the long, high
quality bark fibre at final harvest were generally small and not significant.
However, regression analysis of the response of bark percentage suggested a
linear decline with increasing initial density.
Feeding by redlegged earth mite (Halotydeus destructor) on seedlings influences subsequent plant performance of different pulse crops
Authors: Liu A. , Ridsdill-Smith T. J.
Published: September 2002

Damage caused by redlegged earth mite to seedlings of 6 pulse species and its
effect on subsequent plant growth and grain yield were examined under
controlled and field conditions. Seedling damage caused by redlegged earth
mite affected subsequent plant growth and reduced seed yield, but the
responses varied among different pulse species. Field pea and yellow lupin
were the most susceptible at seedling stage and flowering, but only yellow
lupin suffered significant reduction in grain yield (30%) in the field.
Narrow-leafed lupin suffered moderate damage, faba bean slight damage, while
chickpea and lentil suffered little or no damage. The practical implications
of these results are discussed.
Evaluating faba beans for resistance to ascochyta blight using detached organs
Authors: Kohpina S. , Knight R. , Stoddard F. L.
Published: September 2002

Detached-organ techniques were developed, using either individual leaves or
stem segments with attached leaves, for use in genetic studies on resistance
to ascochyta blight in faba beans. A single isolate of
Ascochyta fabae, A26, was used to infect the highly
resistant population ILB 752, moderately resistant cultivar Fiord and highly
susceptible population NEB 463. Cultural conditions were established that
maintained the detached organs in good condition for more than the 10 days
required for disease symptoms to be expressed. Detached organs were scored for
presence, number and size of lesions and also for number of lesions bearing
pycnidia. Spore suspensions of 5 x 102 to 2 x
106 per mL were used, with 5 x 104
providing as much infection as greater concentrations. Leaves and stems were
taken from 3-, 5- or 7-week-old plants. Younger plant parts were more
susceptible than older ones and plants aged 3–5 weeks provided adequate
material for the tests. The susceptibility of the 3 accessions in these
experimental conditions followed the order expected from field trials.
Weighing and assay in the early days of the Melbourne Branch of the Royal Mint
Authors: Bolton H. C. , Williams Nicola H.
Published: September 2002

The Melbourne Branch of the Royal Mint was founded in response to demand from prospectors and the rapidly increasing Victorian population for a viable currency. Its basic function was to assay the precious metals received, which relied on accurate weighing. Various officers of the Mint, including Robert Barton, George Foord, Robert Law and Carl Otto added refinements that contributed to the speed and reliability of this process. The Melbourne Mint operated from 1872 until 1968, although gold refining ceased in June 1964, and it then concentrated on producing threepenny and penny pieces, and also one- and two-cent bronze coins for the new decimal currency. The Royal Australian Mint, Canberra, was commissioned in 1965 and decimal currency was introduced on 14 February 1966.
A systematic revision of Japanese Trichadenotecnum Enderlein (Psocodea:'Psocoptera':Psocidae:Ptyctini), with redefinition and subdivision of the genus
Authors: Yoshizawa Kazunori
Published: September 2002

The genus Trichadenotecnum Enderlein, 1909 is redefined
as a monophyletic group. The following 22 Japanese species are treated and
classified into five species-groups except one species not placed in a group:
sexpunctatum-group –
T. album, sp. nov., T. incognitum
Roesler, 1939; medium-group –
T. takahashii, sp. nov.,
T. mixtum, sp. nov.,
T. magnomixtum, sp. nov.,
T. amamiense, sp. nov.,
T. okinawense, sp. nov.,
T. yonaguniense, sp. nov.,
T. kumejimense, sp. nov.,
T. latebrachium, sp. nov.,
T. pseudomedium, sp. nov.,
T. yaeyamense, sp. nov.;
alexanderae-group –
T. alexanderae Sommerman, 1948,
T. castum Betz, 1983,
T. sexpunctellum (Enderlein, 1907);
majus-group –
T. yamatomajus, sp. nov.,
T. nothoapertum, sp. nov.;
spiniserrulum-group –
T. falx, sp. nov., T. furcalingum,
sp. nov., T. pardidum Thornton, 1961,
T. circularoides Badonnel, 1955;
incertae sedis –
T. fuscipennis, sp. nov. The monophyly and phylogenetic
relationships of these species-groups are discussed. A key to Japanese species
of Trichadenotecnum is given.
Platypodidae under scrutiny
Authors: Kuschel Guillermo , Leschen Richard A. B. , Zimmerman Elwood C.
Published: September 2002

The historical status of the family Platypodidae is reviewed and the family is
revised. Results of a cladistic analysis based on 35 terminal taxa and 80
adult morphological characters show that the current placement of Platypodidae
makes the subfamily Scolytinae paraphyletic. Moreover, several important
genera included in Scolytinae are shown to be members of Cossoninae (i.e. the
placement of Protoplatypus Wood and
Phylloplatypus Kato in Cossoninae is confirmed). Based
on these results, the status of Platypodidae as a family and subfamily is
rejected, Scolytinae thereby becoming a monophyletic taxon.
Araucarius groups in Scolytinae instead of Cossoninae in
the analysis on a single step only, but it is suggested that it be retained in
Cossoninae until this subfamily is submitted to a similar phylogenetic study.
Three genera and four species of Cossoninae are described as new:
Dobionus Kuschel, gen. nov.: type species
D. araucarinus Kuschel, sp. nov. (with the inclusion of
D. brachyrhinus (Montrouzier));
Coptonus Kuschel, gen. nov.: type species
C. fijianus Kuschel, sp. nov. (with the inclusion of
C. papuanus Kuschel, sp. nov.) and
Dissostomus Kuschel, gen. nov.: type species
D. hornabrooki Kuschel, sp. nov.
Substantial allozyme diversity in the freshwater crayfish Parastacoides tasmanicus supports extensive cryptic speciation
Authors: Hansen B. , Adams M. , Krasnicki T. , Richardson A. M. M.
Published: September 2002

Allozyme electrophoretic studies on the freshwater crayfish genus
Parastacoides Clark suggest the presence of several
cryptic species within this morphologically conservative taxon. Two
independent allozyme studies were undertaken to assess the validity of the
current taxonomy of this monotypic genus. An initial study examined 42
individuals from 10 sample sets for allozyme variation at 22 putative loci,
and a subsequent study surveyed an additional 72 specimens from 20 sample sets
at 16 putative loci. Both studies revealed the same general outcomes, namely:
(1) several instances of sympatric species diagnosable
at multiple allozyme loci; (2) numerous examples of
putative allopatric species with significant levels of genetic divergence
(25–81% fixed difference, 0.30–1.67 Nei distance) well
beyond those found between conspecific populations of any parastacid;
(3) broad genetic affinities among putative species are
inconsistent with currently recognised morphotypes; and
(4) low levels of within-population genetic variability,
typical of parastacids. Although it is not possible to determine how many
species are represented on the basis of these two preliminary studies, the
allozyme data nevertheless indicate that an absolute minimum of 11 species and
perhaps as many as 19 species are likely to be present in the genus. They
indicate the need for a thorough taxonomic revision of the genus using both
molecular and morphological data.
Allozyme evidence for a new species of freshwater crayfish of the genus Cherax Erichson (Decapoda : Parastacidae) from the south-west of Western Australia
Authors: Austin C. M. , Ryan S. G.
Published: September 2002

The marron, Cherax tenuimanus (Smith), is one of the most easily recognisable members of the freshwater crayfish genus Cherax. Since its description in 1912, the taxonomy of the species has not been in dispute, but recent genetic studies have demonstrated that the species is not homogenous and consists of two genetically distinct forms. One of these forms is widespread and exploited via aquaculture and the other is restricted to a single river system, the Margaret River. This paper presents allozyme data, collected over a 19-year period, which documents the introduction of the widespread form into the Margaret River and the subsequent reproductive interactions between the two forms. These data indicate minimal interbreeding between the two forms of marron and so justify their recognition as distinct species. As the original description of the marron was based on specimens collected from the Margaret River, the form native to this river retains the name C. tenuimanus and a new species, Cherax cainii Austin is described for the common, widespread form of marron. An additional outcome of this study is that C. tenuimanus has been rapidly displaced by the introduced C. cainii within the Margaret River. Consequently, urgent conservation measures are required to protect C. tenuimanus and prevent its possible extinction.
Nothotrichocera Alexander (Diptera : Trichoceridae): new species, redescriptions and phylogenetic relationships within the genus
Authors: Krzeminska Ewa
Published: September 2002

Nothotrichocera antarctica (Edwards),
Nothotrichocera tonnoiri Alexander and Nothotrichocera
tasmanica Alexander are redescribed and a new species of the
cingulata-group, N. collessi, sp.
nov., is described. The eleven species of
Nothotrichocera belong in four well-defined groups of
species, which have evolved in geographically isolated, circum-Antarctic
regions. The unique positions of N. tonnoiri and
N. tasmanica are stressed. A key to the species-groups
is given and a phylogenetic analysis of the genus is presented.
A Revision of the Australian Moth Genus Paralaea Guest (Lepidoptera : Geometridae : Ennominae)
Authors: McQuillan Peter B. , Young Catherine J. , Richardson Alastair M. M.
Published: September 2002

The genus Paralaea Guest is reviewed and includes fourpreviously described species, P. porphyrinaria (Gueée, 1857), P. beggaria (Guenée,1857), P. ochrosoma (R. Felder & Rogenhofer,1875) and P. polysticha (Goldfinch, 1944), and nine newspecies: P. atralba, sp. nov., P. chionopasta, sp. nov., P. jarrah, sp. nov., P. karri , sp. nov., P. maranoa, sp. nov., P. sarcodes, sp. nov., P. taggorum, sp. nov., P. tasmanica, sp. nov. and P. toowoomba, sp. nov. The genus has a Bassiandistribution with some extension into the woodlands of the semi-arid zone. Most species occur in south-eastern Australia with six species in Tasmania. Known larvae feed on Eucalyptus, especially trees of the subgenus Monocalyptus, and one species is an occasionalforest pest.
Temporal variation in the movement of the spiny lobster Jasus edwardsii
Authors: Kelly Shane
Published: September 2002

Of 32 large spiny lobsters tracked with acoustic tags for 14–355 days in
north-east New Zealand, 25 moved detectable distances (>0.1 km) from their
tag site while being monitored. Individual lobsters moved up to 12.3 km over a
12-month period but the furthest distance from a tagging site was only 3.1 km.
Maximum movement rates of 0.029 km day–1 to 1 km
day–1 were recorded, but periods of elevated
movement activity were interspersed with extended periods of little or no
movement. Females were more active toward the end of the egg-bearing season
around September and October. Males displayed two peaks in activity over the
year, one in summer near the start of the new moult cycle, and another in
winter following the mating season. The onset of elevated movement activity
was often accompanied by a shift in the depth distribution of tagged lobsters,
with 12 moving out to offshore sandflats and small, isolated, patch reefs. The
results indicate that adult J. edwardsii have high site
fidelity, spending extended periods in relatively small areas of inshore reef.
However, lobsters leave their coastal reef sites during offshore movements
that appear to be related to the moulting, reproductive and feeding cycles.
Influence of asexual reproduction on the structure and dynamics of Holothuria (Halodeima) atra and Stichopus chloronotus populations of the Great Barrier Reef
Authors: Uthicke S.
Published: September 2002

To determine the effect of asexual reproduction by transverse fission on the
population structure of holothurians, ensities and individual weights of
Holothuria atra (JÄÄger,1833)and
Stichopus chloronotus (Brandt, 1835)were measured over a
26-month period on near-shore reefs of the Great Barrier Reef. Densities of
H.atra (0.01—0.69 individuals m
–2 )and S. chloronotus
(0.11—1.67) did not increase during periods of intense asexual
reproduction, and the density on each reef remained relatively stable.The
effect of fission was clearly visible in the weight —frequency
distributions of both species. The average individual wet weight in each
population declined (H. atra from 105/134 g to
64/94 g in two respective populations;S. chloronotus
from 128/302 g to 82/190 g in two respective populations) with the
onset of fission in early winter, and more individuals in the weight range of
fission products were found. The biomass followed the seasonal trend of the
average weights for both species, with minimum values in winter. A conceptual
model based on these and previous findings identified five possible factors
(mortality, habitat stability, optimum individual size, food availability,
larval supply) involved in promoting or repressing transverse fission, and the
model indicated the consequences for the population.
How efficient is extraction of stream insect larvae from quantitative benthic samples?
Authors: Marchant R. , Hehir G.
Published: September 2002

The efficiency of extraction of
Agapetus larvae (Glossosomatidae : Trichoptera) from
quantitative benthic samples was estimated by the use of two approaches: an
indirect estimate based on the probability of missing a specimen in two scans
of a sample (the two-count method) and a direct estimate derived by re-picking
samples. Both approaches gave similar estimates for the probability of missing
a specimen of a given size and both showed that this probability increased as
size decreased; losses ranged from 6% to 30%. The two-count
method thus provides a reliable way to compensate for these losses. Such
corrections made little difference to conclusions concerning
Agapetus population density, larval growth or secondary
production derived from a previous study. However, when no corrections are
applied, mortality estimates may be inaccurate if early instars are picked
with less efficiency than later ones.
Behavioural responses to alarm odours in indigenous and non-indigenous crayfish species: a case study from Western Australia
Authors: Gherardi Francesca , Acquistapace Patrizia , Hazlett Brian A. , Whisson Glen
Published: September 2002

The assertion that invasive species show higher plasticity in the use of
information than indigenous ones was analysed in an indigenous crayfish
Cherax tenuimanus (marron) and the non-indigenous
C. albidus (yabby) in temperate Western Australia. In
the laboratory, both species displayed a measurable change in their behaviour
when presented with odours produced by food and by damaged conspecifics. They
also reacted to heterospecific cues, possibly because ~70 years of sympatry
had led the two species to learn each other’s alarm signals. However,
this may be explained as a case of phylogenetic inertia and/or may be
related to similar mechanisms of chemical detection. Yabbies displayed shorter
reaction times and clearer changes in their body posture to heterospecific
odours than did marron, supporting the view that invasive crayfish make faster
and more appropriate use of information than those species they are
displacing.