bluuebunny/crossref_metadata_2025 huggingface dataset:
The nutritive value of citrus pulp ensiled with wheat straw and poultry litter for sheep
Authors: Migwi P. K. , Gallagher J. R. , van Barneveld R. J.
Published: September 2002

In experiment 1, 4 treatments were prepared consisting of a mixture of chopped
wheat straw in different proportions, a fixed proportion of poultry litter and
0, 15, 30 and 45% citrus pulp on a dry matter basis. The mixtures were
ensiled for 60 days at room temperature in polythene bags. Ensiling (time
effect) resulted in an increase (P<0.001) in titrable
acidity level and a decrease in pH in the silage. In titrable acidity, there
was an interaction effect (P<0.001) between the
levels of citrus pulp and the ensiling time, such that there was an increase
(P<0.001) in titrable acidity and a decrease
(P<0.001) in pH in the 4 treatments both before and
after fermentation. However, compared with the premix, there was a large
increase in titrable acidity in silage following fermentation. Ensiling
resulted in complete elimination of all coliforms in spite of their presence
in large numbers in the mixtures before ensiling. Although the total nitrogen
content was not affected, ensiling resulted in an increase
(P<0.05) in the proportion of soluble nitrogen. The
potential degradability of the silage dry matter ranged from 487 to 582
g/kg and increased (P<0.05) with the level of
citrus pulp. In experiment 2, the daily intake of dry matter, organic matter,
digestible organic matter and the digestibility of organic matter increased
significantly with levels of citrus pulp in the basal silage diet, but there
was no difference (P>0.05) in dry matter intake
between diets containing 0, 76 and 167 g/kg citrus pulp when the intake
was expressed on the basis of metabolic body weight. However, there was a
decrease (P<0.001) in intake of silage and diet dry
matter, organic matter and digestible organic matter when the level of citrus
pulp in the basal silage diet increased from 167 to 272 g/kg. Only animals
on the basal silage diet containing 167 g/kg citrus pulp had a higher
(P<0.05) and positive nitrogen balance of 1.0
g/day. It is concluded that wheat straw and poultry litter can be ensiled
successfully with citrus pulp to produce silage that is safe and of high
fermentation quality. This silage has a medium to high feeding value in sheep,
provided that the level of citrus pulp in the diet is in the range of
150–200 g/kg.
Nutritional constraints on root nodule bacteria affecting symbiotic nitrogen fixation: a review
Authors: O'Hara G. W.
Published: September 2002

Root nodule bacteria require access to adequate concentrations of mineral
nutrients for metabolic processes to enable their survival and growth as
free-living soil saprophytes, and in their symbiotic relationship with
legumes. Essential nutrients, with a direct requirement in metabolism of
rhizobia are carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur,
potassium, calcium, magnesium, iron, manganese, copper, zinc, molybdenum,
nickel, cobalt and selenium. Boron does not seem to be required by rhizobia,
but is essential for the establishment of effective legume symbioses. Nutrient
constraints can affect both free-living and symbiotic forms of root nodule
bacteria, but whether they do is a function of a complex series of events and
interactions. Important physiological characteristics of rhizobia involved in,
or affected by, their mineral nutrition include nutrient uptake, growth rate,
gene regulation, nutrient storage, survival, genetic exchange and the viable
non-culturable state. There is considerable variation between genera, species
and strains of rhizobia in their response to nutrient deficiency. The effects
of nutrient deficiencies on free-living rhizobia in the soil are poorly
understood. Competition between strains of rhizobia for limiting phosphorus
and iron in the rhizosphere may affect their ability to nodulate legumes.
Processes in the development of some legume symbioses specifically require
calcium, cobalt, copper, iron, potassium, molybdenum, nickel, phosphorus,
selenium, zinc and boron. Limitations of phosphorus, calcium, iron and
molybdenum in particular, can reduce legume productivity by affecting nodule
development and function. The effects of nutrient deficiencies on
rhizobia–legume signalling are not understood. The supply of essential
inorganic nutrients to bacteroids in relation to nutrient partitioning in
nodule tissues and nutrient transport to the symbiosome may affect
effectiveness of nitrogen fixation. An integration of molecular approaches
with more traditional biochemical, physiological and field-based studies is
needed to improve understanding of the agricultural importance of rhizobia
response to nutrient stress.
More frequent allocation of herbage does not improve the milk production of dairy cows in early lactation
Authors: Dalley D. E. , Roche J. R. , Moate P. J. , Grainger C.
Published: September 2002

Two experiments were conducted to test the hypothesis that offering a given
daily allowance of herbage as smaller feeds more frequently than once per day
will increase daily herbage intake and milk yield.
In experiment 1 (spring 1995), cows in early lactation were offered either 40
or 65 kg DM/cow.day allowance of herbage as either 1 feed or as 6 equal
feeds. The latter cows received a fresh strip of herbage at 0600, 0900, 1100,
1330, 1800 and 2000 hours. The experiment lasted 28 days with treatment
effects being measured from days 15 to 28. There were no significant
differences in herbage intake (15.6 v. 15.9 kg
DM/cow.day), grazing time (9.4 v. 9.5
h/cow.day), milk production (25.4 v. 25.2
L/cow.day) or milk composition between the 1-feed treatment and 6-feed
treatment, respectively, during the final 2 weeks of the experiment.
Increasing herbage allowance increased (P<0.001)
herbage intake. Liveweight loss during the experiment was less
(P<0.05) for 6-feed cows than 1-feed cows.
A similar experiment was conducted in 1996 (experiment 2); however, all cows
were offered a single herbage allowance of 50 kg DM/cow.day. The
frequencies of feeding were the same as in experiment 1 except that a new
strip of herbage was offered to the 6-feed cows at 0800, 1130, 1700, 2030,
2400 and 0330 hours. The experiment comprised 2 intensive measurement periods,
the first in weeks 1 and 2 (period 1) and the second in weeks 4 and 5 (period
2). Herbage intake did not differ between treatments averaging 15.2 and 16.3
kg DM/cow.day for the 1-feedtreatment and 6-feed treatment respectively.
Milk yield declined from 27.1 L/cow.day in period l to 25.6 L/cow.day
in period 2 and was lower for the 6-feed treatment than for the 1-feed
treatment 25.7 and 26.7 L/cow.day, respectively. Offering fresh herbage to
the 6-feed cows between 2000 and 0600 hours decreased the proportion of
daylight hours these cows spent grazing but did not change total grazing time.
Despite the adoption of extreme grazing management procedures in the
experiments reported in this paper, we were unable to increase herbage intake
or milk production of dairy cows in early lactation. It would appear that
farmers have little opportunity to increase herbage intake in early lactation
by increasing the frequency of allocation of pasture
Methods used in the CRC program for the determination of carcass yield and beef quality
Authors: Perry D. , Shorthose W. R. , Ferguson D. M. , Thompson J. M.
Published: September 2002

This paper describes the methodology used for the collection of carcass yield
and meat quality data from straightbred and crossbred cattle in the
Cooperative Research Centre for Cattle and Beef Quality core program.
Effects of perennial ryegrass cultivar, duration of lock up and nitrogen fertiliser application on dairy pasture dry matter yield and quality for silage in south-western Victoria
Authors: Jacobs J. L. , McKenzie F. R. , Ward G. N. , Kearney G.
Published: September 2002

A study in south-western Victoria determined effects of 3 perennial ryegrass
(Lolium perenne L.) cultivars (Vedette, Impact and
Nevis) with differing maturities, duration of lock up and nitrogen (N)
application on the dry matter yield and nutritive characteristics of pasture
for silage. Treatments were cultivar (3), N (0 and 50 kg N/ha) and
duration of lock up (5–10 weeks) arranged in a completely randomised
design in 3 by 5 m plots replicated 3 times. Plots were mown to a uniform
height (5 cm) on 14 September 1998 (first day of lock up) and 1 week later N
was applied as urea (46% N) at either 0 or 50 kg N/ha to the
respective plots. Weekly sampling commenced on 19 October (week 5 of lock up),
and continued until 23 November. For each treatment and harvest date, dry
matter yield and botanical composition were determined, and samples of total
pasture and the ryegrass fraction were collected and chemically analysed for
dry matter digestibility, concentrations of crude protein, neutral detergent
fibre, water-soluble carbohydrates and minerals. Metabolisable energy was
derived from dry matter digestibility.
All pasture types were predominantly ryegrass (>90%) with no
differences in the nutritive characteristics of total pasture swards or the
respective ryegrass fraction. Nitrogen at 50 kg N/ha significantly
(P<0.05) increased dry matter yield for all
cultivars. Metabolisable energy (MJ/kg DM) of the pasture declined with
time for all treatments, with Vedette having a significantly
(P<0.05) greater rate of decline than the other
cultivars. Vedette reached early ear emergence about 3 weeks earlier (week 7)
than the other cultivars. The harvestable metabolisable energy yield
(MJ/ha) at ear emergence was highest for Impact, followed by Nevis and
Vedette.
In conclusion, there is potential to use later-maturing cultivars of ryegrass
in south-eastern Australia to allow for later harvesting of forage for silage,
while maintaining metabolisable energy and maximising dry matter yields.
Furthermore, the use of N fertiliser can also increase dry matter yields
without impinging on pasture quality provided the time between N application
and harvest date does not exceed 5–6 weeks.
Saprophytic microorganisms with potential for biological control of Botrytis cinerea on Geraldton waxflower flowers
Authors: Beasley D. R. , Joyce D. C. , Coates L. M. , Wearing A. H.
Published: September 2002

Saprophytic bacteria, yeasts and filamentous fungi were isolated from
Geraldton waxflower flowers and screened to identify potential antagonism
towards Botrytis cinerea. Isolates from other sources
(e.g. avocado) were also tested. Isolates were initially screened
in vitro for inhibition of
B. cinerea conidial germination, germ tube elongation
and mycelial growth. The most antagonistic bacteria, yeasts and fungi were
selected for further testing on detached waxflower flowers. Conidia of the
pathogen were mixed with conidia or cells of the selected antagonists,
co-inoculated onto waxflower flowers, and the flowers were sealed in glass
jars and incubated at 20˚C. The number of days required for the pathogen
to cause flower abscission was determined. The most antagonistic bacterial
isolate, Pseudomonas sp. 677, significantly reduced
conidial germination and retarded germ tube elongation of
B. cinerea. None of the yeast or fungal isolates tested
was found to significantly reduce conidial germination or retard germ tube
elongation, but several significantly inhibited growth of
B. cinerea. Fusarium sp.,
Epicoccum sp. and Trichoderma spp.
were the most antagonistic of these isolates. Of the isolates tested on
waxflower, Pseudomonas sp. 677 was highly antagonistic
towards B. cinerea and delayed waxflower abscission by
about 3 days. Trichoderma harzianum also significantly
delayed flower abscission. However, as with most of the fungal antagonists
used, inoculation of waxflower flowers with this isolate resulted in unsightly
mycelial growth.
Nitrogen Special Issue: summing up of papers and recommendations for future research
Authors: Wolfe E. C.
Published: September 2002

The 12th Australian Nitrogen Fixation Conference was the third in a series of
national workshops that began in 1991 and dealt with aspects of the nitrogen
dynamics of Australian pastures and croplands. The conference and the papers
published in the Special Issue addressed, at least in part, the slow progress
that is evident in improving the rate of biological nitrogen fixation by
enhancing inoculating techniques and Rhizobium strains.
An important output from the conference was an analysis of nitrogen supply and
demand in Australian dryland crops, indicating less reliance on biological
nitrogen fixation due to higher wheat yields, the increased use of canola in
crop rotations and problems with pulses. In 3 keynote reviews, the factors
affecting the fixation and release of biologically fixed nitrogen to
non-legume crops were comprehensively detailed. These factors included the
frequency of legumes in rotations and their individual biomass rather than the
efficiency of nitrogen fixation itself. The further development and use of
models is a way of predicting outcomes for various combinations of management
and crop rotations. The present trend towards fewer years of legumes in phase
farming in Australia may reverse, resulting in renewed interest in ley
pastures and pulse crops.
Assessing positional accuracy and its effects on rice crop area measurement: an application at Coleambally Irrigation Area
Authors: van Niel T. G. , McVicar T. R.
Published: September 2002

If management decisions are based on geospatial data that have not been
assessed for spatial accuracy, then debate about both the measurements and the
decisions themselves can occur. This debate, in part, can be avoided by
evaluating the spatial accuracy of geospatial data, leading to heightened
confidence in both the data and the decisions made from the data. To increase
the effectiveness of environmental compliance monitoring, the spatial
accuracies of 2 Geographic Information System datasets were estimated at the
Coleambally Irrigation Area, New South Wales. The first, high-resolution
digital aerial photography acquired in January 2000, is the Geographic
Information System baseline data for Coleambally Irrigation Area. The second,
Digital Topographic Data Base roads data, although not a reference dataset at
Coleambally Irrigation Area, is often used as a baseline dataset across
Australia. Neither dataset met the National Mapping Council of
Australia’s standard of map accuracy, so a new version of the digital
aerial photography was created that did. The positional accuracy of the
improved dataset was over 4 times more accurate than the Digital Topographic
Data Base roads dataset and over 2.5 times more accurate than the original
digital aerial photography. It was also found that the overall areal error of
paddocks measured from the improved dataset decreased as more paddock areas
were added together; a finding that has a direct impact on management
decisions at Coleambally Irrigation Area. This study both provides a
demonstration of how to assess and improve spatial accuracy and shows that
this process is not unduly complicated.
Nitrogen supply and demand in Australian agriculture
Authors: Angus J. F.
Published: September 2002

The supply of and demand for nitrogen by whole industries and individual crops
is discussed in relation to changes in farming systems, particularly the
relative importance of fertiliser and biologically fixed nitrogen. The use of
fertiliser nitrogen (N) in Australia has grown at an annual rate of 14%
since the early 1990s, after growing at half that rate since the 1950s. The
accelerated growth occurred during a period when world demand has been almost
constant. Most of the additional demand has been for the dryland cereal and
canola industries of southern Australia, where crops previously obtained
almost all their N from mineralisation of soil organic matter and the residues
of legume pastures. The most likely reasons for the belated increase in use of
fertiliser N in Australia are to replace the supply from pasture residues as
the area of pasture decreased and to satisfy the increased demand of cereals
following break crops and of the break crops themselves, particularly canola.
For a dryland cereal, there is a problem of matching soil N supply with an
unpredictable N demand. For winter cereals in Australia, crop N demand is
poorly synchronised with soil N supply. The time of greatest demand is
normally during the stem-elongation phase when the crop is growing fastest.
For crops targeted for high-protein grain, there is an even greater demand
around the flowering phase. The peak N demand for well-managed crops growing
with no water limitations exceeds the capacity of the soil to supply N from
mineralisation at the time, so additional N is required to meet the shortfall,
either from fertiliser or mineral N retained in the soil from earlier
mineralisation. Predicting the optimum supply of fertiliser N at sowing is
difficult in cases where N demand is influenced by variable rainfall.
Topdressing and banding fertiliser offer prospects for more closely matching N
supply and demand for dryland crops. The future role of legumes in supplying
residual N is discussed in relation to the trend towards continuous cropping.
Ripening and quality responses of avocado, custard apple, mango and papaya fruit to 1-methylcyclopropene
Authors: Hofman P. J. , Jobin-Decor M. , Meiburg G. F. , Macnish A. J. , Joyce D. C.
Published: September 2002

The potential for the ethylene binding inhibitor, 1-methylcyclopropene, to
delay ripening of ‘Hass’ avocado, ‘African Pride’
custard apple, ‘Kensington Pride’ mango and ‘Solo’
papaya was examined. Fruit were gassed with 25 µL/L
1-methylcyclopropene for 14 h at 20°C, followed by treatment with 100
µL/L ethylene for 24 h, and then ripened at 20°C. Ethylene
treatment alone generally halved the number of days for fruit to reach the
ripe stage, compared with untreated fruit. 1-Methylcyclopropene treatment
alone increased the number of days to ripening by 4.4 days (40%
increase), 3.4 days (58%), 5.1 days (37%) and 15.6 days
(325%) for avocado, custard apple, mango and papaya, respectively,
compared with untreated fruit. Applying 1-methylcyclopropene to the fruit
before ethylene prevented the accelerated ripening normally associated with
ethylene treatment, so that the number of days to ripening for fruit treated
with 1-methylcyclopropene plus ethylene was similar to the number of days to
ripening for fruit treated with 1-methylcyclopropene alone.
1-Methylcyclopropene treatment was associated with slightly higher severity of
external blemishes in papaya and custard apple, slightly higher rots severity
in avocado, custard apple and papaya, and at least double the severity of stem
rots in mango, relative to fruit not treated with 1-methylcyclopropene. Thus,
1-methylcyclopropene treatment has the potential to reduce the risk of
premature ripening of avocado, custard apple, mango and papaya fruit due to
accidental exposure to ethylene. However, additional precautions may be
necessary to reduce disease severity associated with 1-methylcyclopropene
treatment.
Productivity and water relations of field-grown cashew: a comparison of sprinkler and drip irrigation
Authors: Blaikie S. J. , Chacko E. K. , Lu P. , Müller W. J.
Published: September 2002

Cashew is an emerging crop in the seasonally ‘wet–dry’
tropical regions of northern Australia. In North Queensland flowering and
fruiting of cashew coincides with the dry season (May–November). During
this period growers sprinkler irrigate at 500 L/tree.week. A 3-year
(1996–98) experiment compared this strategy with alternatives, including
no irrigation or drip irrigation in which 115 or 230 L/tree.week was
applied by drippers placed near the tree trunk and near the canopy drip line
throughout the dry season. Measurements of soil water to 1.3 m, leaf gas
exchange, chlorophyll fluorescence, tree sap flow and yield were made. Data
collected in the first 2 years showed that the water requirement of the trees
increased progressively as the crop load and evaporative demand increased
during the dry season. During the final year of the study, additional
sprinkler and drip treatments, in which water applications were progressively
increased during the dry season, were introduced.
The productivity of cashew in this experiment was strongly influenced by
irrigation treatments, ranging (over all years) from 42 to 160 g nut/m
2 canopy surface area. Depletion of plant-available
water in the root zone was associated with a reduction in photosynthesis
mediated by partial stomatal closure. These effects of soil drying were
evident in all irrigated treatments during the mid and late stages of the dry
season but were more severe in treatments receiving the least water. When
irrigation was withheld until the mid-stage of the dry season the trees had
similar yields to those that were irrigated throughout, emphasising the
importance of providing adequate irrigation between nut set and harvest.
When rainfall from January to September in each year of the study was taken
into account, there was a strong linear relationship between nut yield and
water applied (rainfall + irrigation), with each extra kilolitre of
water applied resulting in about 6 extra g nut/m 2
canopy surface area. This linear relationship was based on water application
in the range 25–50 kL per season. It is possible that if the seasonal
water application had exceeded 50 kL the marginal response to extra water may
have diminished. Using drippers was slightly more efficient than sprinklers,
with drip-irrigated trees requiring about 5% less water applied to
achieve a given nut yield. In years when rainfall is average, and subject to
other economic factors, growers in North Queensland should aim to irrigate
about 500 L/tree.week.
In years of low rainfall between January and September it is likely that yield
will be improved by applying more irrigation water; high rainfall during these
months of the year may reduce the irrigation requirement. In all cases growers
should be careful to accurately monitor water applications, particularly when
the total (from rainfall + irrigation) exceeds 40 kL/tree for the
season.
Response of winter-sown carrots (Daucus carota L.) to rate and timing of phosphorus application on Joel sands
Authors: McPharlin I. R. , Lanztke N. C.
Published: September 2002

The response of winter-sown carrots to rate and timing of phosphorus
application on Joel sands was investigated at 2 commercial vegetable property
sites on the Swan Coastal Plain in 1996. Phosphorus was applied at rates from
0 to 160 kg/ha at 2 times of application either 100% broadcast to
the soil surface and incorporated before sowing (BS) or 25% broadcast
and incorporated before sowing with 75% broadcast to the soil surface
(not incorporated) after sowing in 5 equal-sized applications of 15%
every 3 weeks, commencing 3 weeks after sowing (BS + AS ).
There was a significant increase in total yield in response to rate and time
of application of phosphorus at both sites. Total yield was 3–10%
higher in the BA + AS than in the BS treatment at site 1 and
10–35% higher at site 2. Marketable yield was 21% higher
at site 2 in the BS + AS compared with the BS treatment. Total and
marketable yields were maximised at 40–80 kg/ha applied P at both
sites.
The concentration of phosphorus (%DW) in the youngest mature leaves at
mid-growth was up to 30–35% higher in the BS + AS than
in the BS treatment. Consequently, the percentage of phosphorus corresponding
to the rate of applied phosphorus necessary for maximum yield was higher in
the BS + AS than in the BS treatment. Thus, critical concentrations
of phosphorus in the youngest mature leaves required for maximum yield of
carrots should take account of timing of phosphorus application.
Exponential regressions best described the relationship of phosphorus uptake
(phosphorus concentration yield) by roots or whole plants to rate and timing
of applied phosphorus. Phosphorus uptake by roots and whole plants increased
with rate of applied phosphorus and was higher in the BS + AS than in
the BS treatment. Recovery efficiency of fertiliser phosphorus by whole plants
was 2.0–3.0-fold higher in the BS + AS treatment than in the BS
treatment at 40–80 kg P/ha.
Effect of sample preparation on in situ estimates of protein degradability for white clover herbages
Authors: Cohen D. C. , Doyle P. T.
Published: September 2002

The amount of crude protein in white clover solubilised during ingestion by
cows was determined by collecting swallowed boluses in rumen fistulated cows.
Six experiments were then conducted to determine the effects of sample
preparation on in situ estimates of rumen degradability
of crude protein in white clover (Trifolium repens L.)
herbages. Different methods of preparation were compared with chopped fresh
herbage, a recommended method when this type of feed is
incubatedin situ. Samples of white clover were either:
(i) chopped fresh to 10 mm lengths (FRS), (ii) frozen, freeze-dried and ground
(FRZ/D), (iii) oven-dried at 45°C for 48 h and ground (OD45C),
(iv) oven-dried at 60°C for 48 h and ground (OD60C), or (v) minced
fresh in a food processor (MNC).
The immediate solubilities of crude protein from MNC preparations most closely
approximated measures of the proportion (0.28–0.37) of crude protein
solubilised during ingestion by cows, while immediate solubilities of crude
protein from FRS preparations were low (0.09–0.19). The effective rumen
degradability of protein for FRS was lower
(P<0.05) than for MNC, FRZ/D or the
oven-dried preparations.
The effects of the method of preparation of fresh clover on estimates of rumen
degradable protein and undegraded dietary protein were compared assuming cows
were producing <15 L milk/day. In the 2 experiments comparing FRS
and MNC preparations, the average estimates of rumen degradable protein and
undegraded dietary protein were 158 and 83 g/kg DM, respectively, for FRS,
compared with 189 and 52 g/kg DM for MNC. Over the 4 experiments comparing
fresh and dried preparations, estimates of rumen degradable protein and
undegraded dietary protein for FRS were 140 and 101 g/kg DM, respectively,
and differed from those for FRZ/D of 156 and 70 g/kg DM. The
implications of such differences have been discussed in relation to use of the
in situ technique. It was concluded that no method of
sample preparation will be ideal and it is likely the preferred method of
sample preparation for in situ studies will vary for
fresh herbages compared with conserved forages and concentrates.
Effect of frost on the quality of samples of Janz wheat
Authors: Allen H. M. , Pumpa J. K. , Batten G. D.
Published: September 2002

The effect of frost damage on wheat grain quality was examined in samples of
an Australian Prime Hard wheat cultivar Janz. Wheat grain samples that were
lightly frosted, severely frosted and unfrosted were obtained from the
Riverina district of New South Wales. Each frosted sample was separated by
sieving into 2 fractions by size using a commercial grader that was equipped
with an aspirator. As the degree of frost damage in the samples increased,
grain size decreased, flour extraction decreased, flour ash increased, flour
colour deteriorated, dough strength decreased, baking quality decreased,
α-amylase activity increased and falling number decreased. Quality
assessment of the separated grain fractions showed that the large grains
(>2 mm) in both lightly frosted and severely frosted crops were equal
or better than the unfrosted sample in all tested quality parameters. The
large grain fraction fully met the Australian Prime Hard receival standards
and was of quality commensurate with the grade. Separation of grain by size
was calculated to be commercially viable for up to 50% frost damage. A
commercial flourmill purchased frosted feed grain, followed the sieving
procedure, and produced large grain consistent with unfrosted wheat that was
subsequently used for normal processing.
Seed yield and nutritive value of dry, mature subterranean clover (Trifolium subterraneum L.)
Authors: Ru Y. J. , Fortune J. A.
Published: September 2002

The nutritive value of 26 cultivars of dry, mature subterranean clover was
evaluated at Shenton Park, Perth, Western Australia. The cultivars were
divided into 3 maturity groups according to flowering time and each cultivar
was sown in blocks comprising 4 replicates. The plots were grazed by sheep at
2-week intervals during the growing season. Dry mature plant material and soil
were sampled in summer to examine the effect of grazing and cultivar on seed
yield and nutritive value of feed residues. Cultivars heavily grazed in spring
had a low herbage mass. There was no difference in seed yield and seed weight
between heavily and lightly grazed cultivars. Dry matter digestibility and
mineral content of dry residues was inconsistent for the 2 grazing treatments.
The dry matter digestibility of dry, mature subterranean clover ranged from 40
to 56%, with a wide range of crude fibre, nitrogen and mineral content
for the 26 cultivars. While most minerals in the dry residues were above the
requirement for sheep, 7 cultivars had a zinc content less than the
maintenance requirement for sheep. There was an imbalance for all cultivars in
calcium: phosphorus with a range of 4–10: 1.
Concurrent estimates on the yield and composition of seed indicated that seed
can be resource of minerals for grazing animals in summer. Most cultivars had
a seed yield over 100 g/m2 with that of 9 cultivars
being over 130 g/m2. Seed was rich in nitrogen,
sodium, phosphorus, potassium, magnesium, zinc and copper, and poor in sodium,
calcium and manganese. However, there were no cultivars with an appropriate
ratio of calcium and phosphorus. The imbalance in nitrogen and sulfur was a
result of high nitrogen content with the ratio ranging from 19: 1 to 29: 1.
Ripening of climacteric fruits initiated at low ethylene levels
Authors: Wills R. B. H. , Warton M. A. , Mussa D. M. D. N. , Chew L. P.
Published: September 2002

Mature, unripe mango, peach, custard apple, kiwifruit and tomato were stored
at 20˚C in air containing ethylene at <0.005, 0.01, 0.1 1.0 and 10
L/L. The time to ripen of all the climacteric fruits increased linearly
with logarithmic decrease in ethylene concentration over the whole
concentration range examined. Similar observations were also obtained with
kiwifruit and custard apple held at 0 and 14˚C, respectively. However,
the sensitivity of fruits to ethylene varied with banana and kiwifruit >
custard apple and mango > tomato, avocado and peach. Since the ethylene
level around horticultural produce during marketing is always >0.005
L/L, the time climacteric fruit can be held in an unripe condition is
currently less than optimal but intervention to limit ethylene action would
appear to be only warranted for the most sensitive fruits.
Management of Avena ludoviciana and Phalaris paradoxa with barley and less herbicide in subtropical Australia
Authors: Walker S. R. , Robinson G. R. , Medd R. W.
Published: September 2002

The competitive advantage of barley compared with wheat was quantified for
suppressing seed production of Avena ludoviciana Durieu.
(wild oats) andPhalaris paradoxa L. (paradoxa grass),
and for improving herbicide effectiveness on these major winter grass weeds of
the subtropical grain region of Australia. Eight field experiments were
broadcast with weed seed before sowing wheat or barley, in which the emerged
weeds were then treated with 4 herbicide doses (0, 25, 50, 100% of
recommended rates). Yield reduction from untreated weeds was on average 4
times greater in wheat than in barley, with greater losses from
A. ludoviciana than P. paradoxa.
Barley did not affect weed emergence, but suppressed weed tiller density and,
to a lesser extent, the number of weed seeds per tiller. Seed production was,
on average, 4340 and 5105 seeds/m2 for
A. ludoviciana and P. paradoxa,
respectively, in untreated wheat compared with 555 and 50
seeds/m2 in untreated barley. Weed seed production
following treatment with 25% herbicide rate in barley was similar or
less than that after treatment with 100% herbicide rate in wheat.
Overall, 25% herbicide rate was optimal for both conserving yield and
minimising weed seed production in barley. For wheat, maximum yield was
achieved with 50% herbicide but weed seed production was lowest with
100% herbicide rate. This indicates that weeds can be effectively
controlled in barley with considerably less herbicide than required in wheat,
highlighting the importance of including barley as a part of weed management
strategies that aim to reduce herbicide inputs.
Tactical versus continuous stocking in perennial ryegrass-subterranean clover pastures grazed by sheep in south-western Victoria. 3. Herbage nutritive characteristics and animal production
Authors: Waller R. A. , Sale P. W. G. , Saul G. R. , Kearney G. A.
Published: September 2002

A 4-year grazing experiment was carried out in south-western Victoria to
compare the effect of tactical stocking with continuous stocking on the
persistence of perennial ryegrass (Lolium perenne L.)
and the productivity of sheep used for prime lamb production. Tactical
stocking consisted of variable length summer, autumn and winter rotations and
continuous stocking in spring. The 2 grazing strategies were compared on 2
contrasting pastures: an upgraded pasture, sown with newer cultivars of
perennial ryegrass and subterranean clover
(Trifolium subterraneum L.) with 26 kg
phosphorus/ha.year, and a naturalised perennial ryegrass pasture receiving
6 kg phosphorus/ha.year. Paddocks were grazed by Border Leicester x Merino
ewes, which were mated to a terminal sire to lamb in September. In this final
paper of the series, the effects of the grazing systems and pasture treatments
on animal production and herbage quality are presented.
The liveweights of the ewes were similar across all treatments during autumn
and winter, but the tactically stocked ewes were 3–6 kg lighter than
continuously stocked ewes during spring and summer. The lower liveweight was
attributed to the lower (P<0.001) herbage quality on
the tactically stocked pastures in spring (P<0.001).
Both digestibility and crude protein concentration were about 4 percentage
units lower with tactical stocking in spring. This lower quality was
associated with the higher herbage mass (by 500–900 kg dry
matter/ha) on the tactically stocked pastures, which presumably had a
higher stem:leaf ratio and showed reproductive growth earlier than the
continuously stocked pastures. Although there were differences in ewe
liveweight, this did not affect individual lamb weaning weight or ewe fleece
weight. There were significant increases in production per hectare from
tactically stocked or upgraded pasture treatments due to the higher stocking
rates that could be carried, 9 and 51%, respectively. In 1998, 544
kilograms of lamb per hectare was weaned from continuously stocked paddocks
and 607 kg/ha from tactically stocked paddocks
(P<0.05), and 449 and 702 kg/ha from the typical
and upgraded pastures, respectively.
This study reinforces the view that soil fertility and pasture improvement
have a much greater impact on animal productivity than changes to grazing
method with little effect on per head productivity. The negative impact of
rotational stocking on herbage quality reinforces the need to use these
systems strategically when benefits from increased herbage mass are expected
to increase animal production or overcome sustainability or pasture
persistence problems.
Effects of the concentration of manganese in the seed in alleviating manganese deficiency of Lupinus angustifolius L.
Authors: Brennan R. F. , Longnecker N. E
Published: September 2002

Low concentration of manganese in the seed of narrow-leafed sweet lupin
(Lupinus angustifolius L.) decreased both the
germination of seedlings and grain yield. In lupin, the grain yield obtained
from seeds with increasing the manganese concentration planted on
manganese-deficient soils could not reach grain yields on the maximum yield
plateau reached by applying fertiliser manganese or minimise the amount of
split seed. Consequently, in lupin for maximum grain yield and minimum amounts
of split seed, both adequate manganese in seed and fertiliser manganese are
required on manganese-deficient soils.
A rapid semi-quantitative procedure for screening hydrocyanic acid in white clover (Trifolium repens L.)
Authors: Ayres J. F. , Murison R. D. , Turner A. D. , Harden S.
Published: September 2002

The presence of cyanogenic glucosides in white clover
(Trifolium repens L.) is an anti-nutritional factor due
to the potential for cyanide to pre-dispose selenium deficiency in grazing
animals. Considerable genotypic variation in cyanogenesis occurs in white
clover and it is important that highly cyanogenic white clover lines are
identified to ensure that germpasm used in breeding programs does not lead to
the release of cultivars that exceed safe levels. A procedure for rapid
semi-quantitative screening of large white clover germplasm collections is
described. This procedure is based on the picrate assay and utilises computer
imagery and calibration relationships between spectral intensity (red, green,
blue bands) of the colour reaction on picrate paper with cyanide in standard
solutions to predict hydrocyanic acid concentration in white clover leaf.
Nitrogen accumulation and distribution at anthesis and maturity in ten wheats grown at three sites in north-western Victoria
Authors: Flood R. G. , Martin P. J.
Published: September 2002

Plant nitrogen relationships were studied in 10 wheat cultivars sown at 3
sites (Horsham, Boort and Walpeup) in north-western Victoria by determining
the nitrogen concentration and nitrogen content of plant components at
anthesis and maturity. While the concentration of nitrogen varied in different
plant components, whole plants at anthesis had a nitrogen concentration below
the value required for maximum growth. The time to anthesis had an influence
only on grain yield and grain nitrogen percentage at Horsham. Total
assimilation of nitrogen at both anthesis and maturity was more strongly
correlated to plant dry matter than plant nitrogen concentration. There was a
significant negative correlation between grain nitrogen percentage and both
nitrogen harvest index and harvest index. Grain yield was strongly correlated
with total nitrogen accumulated at anthesis and more strongly correlated with
total nitrogen accumulated at maturity. Grain yield was significantly
correlated with nitrogen harvest index and more strongly correlated with
harvest index. Grain yield was negatively correlated with grain nitrogen
percentage. The negative association between grain nitrogen percentage and
harvest index has important implications for the breeding of wheat with higher
grain nitrogen percentage while maintaining or increasing grain yield. The
results indicated that none of the measured parameters could be used for
indirect selection aimed at improving grain nitrogen percentage.
Grazing management to increase utilisation of phalaris-based pasture in dryland dairy systems
Authors: Watson D. J. , Avery A. , Mitchell G. J. , Chinner S. R.
Published: September 2002

Phalaris (Phalaris aquatica cv. Sirosa)-based pastures
at Sandy Creek (north-eastern Victoria) and Flaxley (South Australia) were
subjected to grazing strategies based on different pre- and post-grazing
pasture dry matter levels for 3 years, 1994–96. At Sandy Creek, 3
treatments consisted of commencing grazing when either 1600 (1), 2200 (2) or
2800 (3) kg dry matter per hectare (DM/ha) of pasture had accumulated,
with treatments being grazed to a pasture residual of 1200 kg DM/ha.
Grazing strategies were imposed over autumn–winter. At Flaxley, there
were 5 treatments. Grazing commenced when either 1800 (1) or 2200 (2) kg
DM/ha of pasture had accumulated, and was grazed to a pasture residual of
1200 kg DM/ha. Also when either 2200 (3) or 2600 (4) kg DM/ha of
pasture had accumulated and these treatments were grazed to a pasture residual
of 1800 kg DM/ha. A further treatment was when phalaris had reached a
4-leaf stage (5) (4 fully expanded leaves per tiller) and this was grazed to a
residual of 1200 kg DM/ha. The grazing strategies were imposed over the
autumn, winter and spring.
Pasture consumption at Sandy Creek was higher in treatments 2 and 3. Pasture
metabolisable energy (ME) levels and crude protein contents were not affected
by treatment. Pasture consumption at Flaxley was greater in treatments 2 and
4. The strategy of grazing at the phalaris 4-leaf stage (5) showed potential
for large spring growth. The ME of pasture was unaffected by treatments.
The optimal grazing strategy to increase pasture growth for phalaris cv.
Sirosa-based pastures in winter-dominant rainfall zones of temperate
Australia, receiving about 700 mm average annual rainfall appears to be:
allowing 2200 or 2600 kg DM/ha of pasture to accumulate before grazing
back to a pasture residual of 1200 or 1800 kg DM/ha, respectively.
Effect of leucaena supplementation level, and provision of urea, on utilisation by sheep of Rhodes grass hay
Authors: Karda I. W. , Dryden G. McL.
Published: September 2002

Tarramba leucaena (Leucaena leucocephala cv. Tarramba)
foliage had per kilogram dry matter, 169 g protein and 29.8 g condensed
tannins. Its value as a supplement, given either with or without urea, to
sheep given a low-quality Callide Rhodes grass
(Chloris gayana cv. Callide) hay was studied. Six rumen
fistulated sheep (mean s.d. liveweight, 34 1.4 kg) were used to compare 6
dietary treatments in an incomplete latin square design. Rhodes grass hay was
given ad libitum either alone, or with urea 7 g/day
(U), or with leucaena 150 g/day (L150), or leucaena with urea (L150U), or
leucaena 300 g/day (L300), or leucaena with urea (L300U). Digestible
organic matter intake was increased significantly by leucaena supplementation
although digestibility of the whole diet did not alter. Rumen fluid ammonia-N
was not altered by leucaena supplementation, but was increased by urea. This
suggests that Tarramba foliage protein has some resistance to ruminal
degradation. Liquid and solids passage rates were not affected by the
treatments. Microbial nitrogen supply to the intestine (g/day), and the
efficiency of microbial nitrogen synthesis (g/kg organic matter apparently
digested in the rumen), were increased by leucaena supplementation
(P<0.01). Microbial protein synthesis was the only
response in which 300 g/day air-dry Tarramba foliage gave improved results
over 150 g/day.
Application of molecular techniques to studies in Rhizobium ecology: a review
Authors: Thies J. E. , Holmes E. M. , Vachot A.
Published: September 2002

The symbiosis between legumes and their specific root-nodule bacteria,
rhizobia, has been employed to improve agricultural productivity for most of
the 20th century. During this time, great advances have been made in our
knowledge of both plant and bacterial genomes, the biochemistry of the
symbiosis, plant and bacterial signaling and the measurement of nitrogen
fixation. However, knowledge of the ecology of the bacterial symbiont has
lagged behind, largely due to a lack of practical techniques that can be used
to monitor and assess the performance of these bacteria in the field. Most
techniques developed in the last few decades have relied on somehow
‘marking’ individual strains to allow us to follow their fate in
the field environment. Such techniques, while providing knowledge of the
success or failure of specific strains in a range of environments, have not
allowed insight into the nature of the pre-existing rhizobial populations in
these sites, nor the interaction between marked strains and the background
population. The advent of molecular techniques has revolutionised the study of
Rhizobium ecology by allowing us to follow the flux of a
variety of ecotypes within a particular site and to examine how introduced
rhizobia interact with a genetically diverse background. In addition,
molecular techniques have increased our understanding of how individual
strains and populations of root-nodule bacteria respond to changes in the
environment and how genetic diversity evolves in field sites over time. This
review focuses on recently developed molecular techniques that hold promise
for continuing to develop our understanding of Rhizobium
ecology and how these can be used to address a range of applied problems to
yield new insights into rhizobial life in soil and as legume symbionts.
Taxonomy and phylogeny of the New Zealand longicorn beetle genus Calliprason White (Coleoptera : Cerambycidae : Cerambycinae)
Authors: Song Deping , Wang Qiao
Published: September 2002

The New Zealand cerambycid genus Calliprason White is
revised, the scope of this genus is redefined, and all species are
redescribed. Four monotypic genera, Stenopotes Pascoe,
Drotus Sharp, Pseudocalliprason
Broun, and Epheus Broun, are synonymised with
Calliprason. As a result of this revision, the number of
species in Calliprason has increased to five. A key to
the five species is given. Terminalia of both sexes are illustrated and
described. Cladistic analysis suggests that the revised
Calliprason is a monophyletic genus supported by 15
synapomorphies. Subdivisions of species groups are discussed. This genus is
mainly distributed in the North Island of New Zealand with some
representatives in the South Island and the Chatham Islands.
A revision of the genus Allotrochosina Roewer (Araneae : Lycosidae)
Authors: Vink Cor J.
Published: September 2002

The lycosid spider genus Allotrochosina Roewer is
reinstated with two valid species: A. schauinslandi
(Simon) (New Zealand), which is redescribed, and
A. karri, sp. nov. (Western Australia). Notes on the
subfamilial placement, biology, distribution and biogeography of
Allotrochosina are given.
Phylogenetic revision of Agapophytus Guérin (Diptera : Therevidae : Agapophytinae)
Authors: Winterton Shaun L. , Irwin Michael E.
Published: September 2002

Morphologically diverse and species-rich, the endemic Australasian genus
Agapophytus is revised. Eleven previously described
species are redescribed and twenty-nine species are described for the first
time: A. adonis, sp. nov.,
A. annamariae, sp. nov.,
A. antheliogynaion, sp. nov.,
A. asprolepidotos, sp. nov.,
A. atrilaticlavius, sp. nov.,
A. biluteus, sp. nov.,
A. borealis, sp. nov.,
A. caliginosus, sp. nov.,
A. cerrusus, sp. nov.,
A. chaetohypopion, sp. nov.,
A. chrysosisyrus, sp. nov.,
A. decorus, sp. nov., A. dieides,
sp. nov., A. discolor, sp. nov.,
A. eli, sp. nov., A. fenestratum,
sp. nov., A. galbicaudus, sp. nov.,
A. labifenestellus, sp. nov.,
A. laparoceles, sp. nov.,
A. lissohoplon, sp. nov.,
A. lyneborgi, sp. nov.,
A. notozophos, sp. nov.,
A. novaeguineae, sp. nov.,
A. pallidicrus, sp. nov.,
A. palmulus, sp. nov.,
A. paramonovi, sp. nov.,
A. septentrionalis, sp. nov.,
A. yeatesi, sp. nov. and A. zebra,
sp. nov. All 40 species of Agapophytus were compared in
a cladistic analysis with three species of Acupalpa
Kröber using 134 states across 58 adult morphological characters. The
analysis resulted in 36 most parsimonious trees with a length of 240 steps.
The phylogenetic relationships of the species of
Agapophytus are discussed with three main clades
recognised: A. dioctriaeformis clade,
A. australasiae clade and
A. queenslandi clade.
New species of Mexicope, stat. nov. and Ianthopsis from Australia and a rediagnosis of Acanthaspidiidae (Isopoda : Asellota)
Authors: Just Jean
Published: September 2002

Two new species, Mexicope westralia and
Ianthopsis vanhoeffeni, are described from south-western
and south-eastern Australia respectively. One species of
Mexicope was known previously from the Gulf of Mexico
and the Caribbean. New morphological evidence shows that
Mexicope, hitherto considered as family
incertae sedis, should be transferred to the
Acanthaspidiidae. New diagnoses are presented for the family Acanthaspidiidae
as well as the genera Mexicope and
Ianthopsis. The distribution of species in the
Acanthaspidiidae is summarised. The vertical distribution patterns of the
three genera in the family (Acanthaspidia,
Ianthopsis, Mexicope) are shown to
be very different. It is suggested that the family originated in cold water of
the southern hemisphere at lower shelf to upper bathyal depth
(Ianthopsis) with subsequent evolution and radiation of
Acanthaspidia in the deep sea and
Mexicope in shallow warmer to tropical waters.