bluuebunny/crossref_metadata_2025 huggingface dataset:
Turnips and protein supplements for lactating dairy cows
Authors: Moate P. J. , Grainger C. , Dalley D. E. , Martin K. , Roche J. R. , Hannah M.
Published: September 2002

Many farmers in southern Victoria grow fodder turnips as a summer feed for
lactating dairy cows. This paper reports on 2 experiments that measured the
milk yields and liveweight changes of cows offered a basal forage diet and
combinations of turnips, barley and protein supplements (cottonseed meal or
lupins).
A stall feeding experiment was conducted over 26 days with 40 Friesian cows in
mid lactation offered 1 of 5 dietary treatments. All cows were offered 10 kg
DM/day of a basal diet comprising pasture, pasture hay and pasture silage
which is similar to that available on many southern Victorian dairy farms
during summer. Cows in a control group did not receive additional feed
supplements. Cows in the other 4 groups were offered a supplement of 5 kg
DM/cow.day of either turnips, barley or a mixture containing 3 kg
DM/cow.day of turnips and 2.0 kg DM/cow.day of either crushed lupins
or cottonseed meal. The marginal milk responses from barley, turnips, turnips
+ lupins and turnips + cottonseed meal were 0.80, 0.92, 1.15 and
1.00 L/kg DM of supplement eaten. There were no significant differences
(P>0.05) in the liveweight changes of the
supplemented groups. Samples of the feeds used in this experiment were placed
in nylon bags and incubated in the rumen of non-lactating dairy cows. The
‘Ørskov’ protein degradation parameters for these feeds are
compared with the published values for a range of Australian feeds. The rate
and extent of degradation of protein from the turnip leaves, turnip bulbs and
crushed barley were all similar.
A grazing experiment was conducted over 65 days with 56 Friesian cows in mid
lactation, offered 1 of 4 dietary treatments. All groups were allowed to graze
pasture (5 kg DM/cow.day), were offered 3 kg DM/cow.day of pasture
silage and were fed different combinations of barley, cottonseed meal and
lupins. In addition, 3 of the groups separately strip-grazed turnips (about 5
kg DM/cow.day). The group fed a supplement of 8.0 kg/cow.day of barley
yielded similar quantities (18.3 L/cow.day) of milk and milk constituents
as another group fed 4.0 kg DM/cow.day of barley and 4.5 kg DM/cow.day
of turnips. Furthermore, when either 1.5 kg DM of cottonseed meal or 2.0 kg of
lupins were fed in place of barley, milk yield increased by 1.4 L/cow.day.
Dietary treatment had no significant (P>0.05) effects
on liveweight changes. From this grazing experiment it is concluded that
turnips can be used as a cheaper alternative to barley in order to maintain
high levels of milk production in summer–autumn. We estimate that if the
above quantities of protein supplement were fed with turnips, at 1997–98
prices, lupins would increase profits by 12 cents/cow.day, but there would
be no financial benefit from the cottonseed meal.
The findings from both experiments show that supplements of rumen-degradable
protein (lupins) can produce an economic milk response when fed to cows on
typical summer diets (pasture/silage/barley and turnips) in southern
Victoria.
A comparison of the topmaking performance of wool from sheep selected by index and visual methods
Authors: Vizard A. L. , Hansford K. A.
Published: September 2002

Summary. The topmaking performance of fleeces from sheep
that were ranked high or low on index selection using objective measurement
was compared with that of sheep from the same flock that were ranked high or
low on visual assessment.
A flock of 451 15-month-old fine-wool Merino sheep were classed by 2
experienced fine-wool sheep classers into 3 grades: best, average and culls.
Forty-four sheep were assessed as ‘best’ and 77 sheep were graded
as ‘culls’ by both classers. These sheep were defined as the
‘best visual’ and ‘worst visual’ sheep, respectively.
Measurements of clean fleece weight, mean fibre diameter, coefficient of
variation of fibre diameter and body weight were used in a selection index to
rank all sheep in the flock. The selection index was designed to rapidly
reduce mean fibre diameter and slowly increase clean fleece weight, whilst
maintaining staple strength and body weight. The 44 sheep with the highest
index value were defined as ‘best index’ sheep and the group of 77
sheep with the lowest index or obvious physical faults were defined as the
‘worst index’ sheep. Twenty-five fleeces were randomly selected
from each of the ‘best’ and ‘worst visual’,
‘best’ and ‘worst index’ sheep for individual
processing through to top.
The fleeces from the ‘best index’ sheep produced greater
quantities of tops that were significantly finer, longer, of lower curvature
and produced less noil than all other groups. In contrast to the large
difference in quality between tops from the ‘best’ and
‘worst index’ sheep, there was little difference in quality
between tops from the ‘best’ and ‘worst visual’ sheep.
This indicates that the traditional wool producer views of wool quality are
unrelated to processing performance. It was concluded that Merino sheep
selected by index selection using direct measurement of fleece weight, mean
fibre diameter and coefficient of variation of diameter as selection criteria
produced greater quantities of wool of superior processing performance to that
from sheep selected using visual assessment.
Effect of cincturing and chemical treatments on growth, flowering and yield of mango (Mangifera indica L.) cv. Kensington Pride
Authors: Blaikie S. J. , Leonardi J. , Chacko E. K. , Muller W. J. , Scott N. Steele
Published: September 2002

Summary. Mango (Mangifera indica
cv. Kensington Pride) is the main horticultural tree crop grown in the
tropical regions of northern Australia. A major problem for growers is that
flowering and fruiting of this cultivar is highly variable from year to year.
A series of field experiments was conducted to evaluate cincturing and
chemical treatments as a means of improving mango productivity. A standard
cincture (Cincture) was compared with a modified technique in which twine was
tied tightly into a cincture groove (Twine). The chemical treatment was based
on a morphactin formulation (MF) and was introduced to the trees by either
painting directly onto the bark of the tree trunk (MF-paint) or soaking twine
in MF before tying it into a trunk cincture (MF-twine). The amount of
morphactin applied varied with tree age and was in the range from 0–0.06
g active ingredient (a.i.) per tree. Tree responses, measured in terms of
vegetative growth, flowering and fruiting, were compared with trees that had
been treated with a physical cincture only, or with paclobutrazol (up to 5.0 g
a.i.), applied as a collar drench.
In young (3–8-year-old) trees, Twine, MF-twine and MF-paint had a
positive effect on flowering and fruiting. These trees had earlier, more
intense flowering, produced early (September) maturing fruit (up to about
4-fold increase) and had high fruit production (up to about 2-fold increase in
fruit number) compared with controls. In some cases vegetative growth was
reduced by 50–60% compared with untreated trees. Twine and
MF-twine are favoured over MF-paint because (i) the paint must be applied
annually, incurring high labour costs, and (ii) paint treatments carry the
risk of overdosing the trees with morphactin. The positive effects of Twine
and MF-twine treatments were sustained, with large responses in flowering
and/or fruiting 2–4 years after application. The responses in fruit
production from paclobutrazol, applied at rates based on manufacturer’s
recommendations, were less than with Twine, MF-twine or MF-paint.
Lupin grain yields and fertiliser effectiveness are increased by banding manganese below the seed
Authors: Brennan R. F.
Published: September 2002

The effectiveness of manganese fertiliser for seed (grain) production of lupin
(Lupinus angustifolius L.) was measured in 31 field
experiments when manganese sulfate, applied at 0–15 kg manganese/ha
was either: (i) placed (drilled) with the seed at about 5 cm; (ii) applied to
the soil surface (topdressed) before sowing; or (iii) banded about 8 cm below
the seed (13 cm below the soil surface) while sowing. Relative to the
nil-manganese treatment, additions of manganese fertiliser increased yields by
190–1870 kg seed/ha. Increases were greatest for manganese banded
below the seed (average increase 1100 kg seed/ha) followed by manganese
drilled with the seed (average increase 845 kg/ha), while the topdressed
manganese fertiliser was least effective (average increase 670 kg/ha).
Additions of manganese fertiliser did not affect plant density (measured 1
month after sowing) or the yield of dried shoots. A concentration of manganese
in the main stem of about 20 mg/kg was a reliable predictor of manganese
deficiency in lupin grain yield. It is therefore recommended that manganese
fertiliser is banded about 8 cm below the seed while sowing lupin rather than
the present practices of either drilling the manganese fertiliser with the
seed or topdressing it before sowing.
Cutflower characteristics of terminal flowering tropical Grevillea: a brief review
Authors: Beal P. R. , Joyce D. C.
Published: September 2002

Summary. The large and colourful cut inflorescences of
the terminal flowering tropical Grevillea species and
hybrids are considered by enthusiasts to have potential as a cutflower crop.
Developing understanding of the characteristics of grevillea inflorescences is
collated in this review article. Botany, quality, cultivars, production and
marketing, physiology and biochemistry, growth and development, flowering
regulation, senescence, postharvest losses, pests and diseases, loss reduction
measures, and use of floral preservatives for cut inflorescences are
discussed. This overview of current knowledge provides a platform for future
research and development on this novel native Australian flower.
The phytotoxicity of the herbicides bromoxynil, pyridate, imazethapyr and a bromoxynil + diflufenican mixture on subterranean clover and lucerne seedlings
Authors: Dear B. S. , Sandral G. A.
Published: September 2002

Summary. The effect of the herbicides pyridate,
imazethapyr and a bromoxynil + diflufenican mixture on subterranean
clover (Trifolium subterraneum L.) (cvv. Trikkala and
Karridale) and lucerne (Medicago sativa L.) (cv. Aurora)
seedlings was examined in randomised plot field experiments in 2 successive
years. Responses were compared against an unsprayed control and a standard
bromoxynil application. The herbicides and the rates of product applied were:
bromoxynil + diflufenican (0.5, 1.0 L/ha), imazethapyr (0.18, 0.3
L/ha), pyridate (1.0, 3.0 L/ha), and bromoxynil (1.4 L/ha). Weeds
were removed by hand from the subterranean clover experiments but not the
lucerne experiments.
Pyridate and imazethapyr were the least phytotoxic of the herbicides applied
on both subterranean clover and lucerne. The bromoxynil + diflufenican
mixture was the most phytotoxic, causing severe leaf burn and a depression in
herbage biomass in both species. Despite the high level of phytotoxicity by
some treatments, none of the herbicides reduced lucerne seedling numbers.
Lucerne herbage yields in late spring were higher in most sprayed plots
compared with the unsprayed control due to the removal of weed competition.
Seed yield responses in subterranean clover due to herbicide application
ranged from negative responses up to –21% with pyridate to
positive responses up to 92% with the bromoxynil + diflufenican
treatment relative to the weed-free, unsprayed control. The positive responses
were attributed to increased availability of soil water during seed set in
treatments in which herbicides suppressed legume biomass. There was a good
correlation in both 1992 (R2
= 0.85–0.89) and 1993
(R2 = 0.63–0.73)
between the depression in herbage yield in spring and the increase in seed set
relative to the control. Soil water under the subterranean clover cultivar
Karridale in spring was highest in the bromoxynil and imazethapyr treatments,
which produced a large reduction in biomass, and lowest in the control and
pyridate treatments, which had showed the least depression in biomass 60 days
after treatment application.
Although some herbicides cause a high level of phytotoxicity, their use in
weedy subterranean clover–lucerne mixtures is justified in view of the
small negative, and potentially large positive, effects on subterranean clover
seed yield and the increased lucerne yields later in the season due to weed
suppression.
The banana selection J.D. Special has longer fruit and heavier bunches than cv. Williams but bunch losses are also increased
Authors: Daniells J. W. , Reid D. J , Bryde N. J.
Published: September 2002

Summary. Yield and plant characteristics of the longer
fingered selection ‘J.D. Special’ were compared with cv. Williams
which is the industry standard. Data from 2 sources
(‘experiments’), including on-farm trials at 6 sites in
Queensland, Australia, (experiment 1) and an experiment at the Queensland
Department of Primary Industries South Johnstone Research Station
investigating maturity bronzing (experiment 2), were utilised for this report.
The fruit on hands 2 or 3 of J.D. Special were on average 10–15%
longer in the crops investigated. Increased finger length occurred along the
entire bunch resulting in 15 and 6% more extra large fruit for J.D.
Special than for Williams in the plant crops of experiments 1 and 2,
respectively. Similar differences were observed in the ratoon crops.
Bunches of J.D. Special were 19–22% heavier than Williams for
plant crops. A combination of greater fruit length and more hands per bunch in
J.D. Special contributed to their greater bunch weight. J.D. Special took
longer from planting to harvest (average of 17days) but yields/unit time
were still 17–19% greater than Williams.
Plants of J.D. Special were more prone to bunch losses with 2 cases of 35 and
45% loss compared with no losses for Williams, the losses being largely
due to wind damage. This susceptibility of J.D. Special is presumably due to
its greater plant height and heavier bunch weight. Fruit greenlife of J.D.
Special was 17% less than Williams in the one crop investigated,
although this was not significant (P>0.10).
Shoot growth, root growth and grain yield of bread and durum wheat in South Australia
Authors: Zubaidi A. , McDonald G. K. , Hollamby G. J.
Published: September 2002

Summary. In South Australia, durum wheat yields more
than bread wheat under well-watered and fertile conditions, but over much of
the state’s cereal belt the yields of durum wheat, relative to bread
wheat, are low. Three experiments were conducted over 3 years at 2 sites to
compare the growth and yield of bread and durum wheat and to investigate some
of the reasons for the differences in the relative yields of the 2 cereals.
Durum wheat yielded less than bread wheat when annual rainfall was less than
about 450 mm or when the site mean yield for bread wheat was less than 250
g/m2. Compared with bread wheat, durum wheat had
poorer early vigour, which was associated with fewer
tillers/m2, and produced fewer
kernels/m2. Under favourable grain filling
conditions, durum wheat produced larger kernels than bread wheat but its
kernel weight was more variable across sites and seasons and consequently, the
relative yields of the 2 cereals depended largely on kernel weight. For
example, in a wet year, durum wheat yielded 20% more than bread wheat,
despite producing 16% fewer kernels/m2,
because of its larger kernels (52 v. 36 mg). In 2 drier
years, kernel weights of durum and bread wheat were similar (durum and bread
wheat mean kernel weights: 40 v. 37 mg; 30
v. 33 mg) and so durum was unable to overcome the
limitation of fewer kernels/m2 and its yields were
similar to or less than bread wheat.
Root length densities of durum and bread wheat below 30 cm were low. Durum
wheat had an equivalent or lower root length density than bread wheat and
lower length per gram of root dry matter, indicating less finely divided
roots. This suggests that durum wheat may sometimes be less able than bread
wheat to utilise moisture and nutrient reserves in the subsoil because of a
smaller root system. This is an undesirable characteristic for a crop that
appears to be more reliant than bread wheat on producing large kernels for
high yields.
Efforts to improve the yield of durum wheat, either through genetic
improvement or by agronomic means, should focus on reducing the levels of
stress during the post anthesis period so that limitations to kernel growth
are minimised. Improving the early vigour of the crop, having cultivars of the
appropriate maturity and with adequate levels of resistance to root disease,
and improving root growth and function in the subsoil are likely to be
desirable characteristics.
Nutrient uptake and distribution by bread and durum wheat under drought conditions in South Australia
Authors: Zubaidi A. , McDonald G. K. , Hollamby G. J.
Published: September 2002

Summary. An important limitation to the production of
durum wheat in South Australia is its poor adaptation to the alkaline, sodic
soils of the cereal belt, which often results in nutrient imbalances in the
crop. A field experiment was conducted at Palmer, South Australia, to measure
the nutrient uptake and distribution between grain and straw of 3 bread wheat
cultivars and 9 cultivars and breeding lines of durum wheat. The purpose of
the work was to characterise the patterns of nutrient uptake and to examine
whether there were major, consistent differences between bread wheat and durum
wheat. Rainfall during the growing season was below average and the crops
suffered from drought stress after anthesis.
Plants were marginally deficient or deficient in nitrogen (N), phosphorus (P)
and zinc (Zn), and boron (B) concentrations were high. Compared with bread
wheat, durum wheat had a very much higher concentration of sodium (Na), higher
concentrations of calcium (Ca) and sulfur (S), but lower concentrations of
potassium (K), magnesium (Mg), manganese (Mn) and copper (Cu). Total amounts
of P, Zn and Na in the shoot continued to increase throughout the growing
season with significant increases occurring during grain filling, whereas
there was little increase in the amount of N, K, B and Mn during grain
filling. The maximum rate of nutrient uptake occurred before the time of
maximum crop growth rate, and was in the order K (10.1 weeks after sowing), N
(10.6), P (11.3), Mn (12.0), Zn (12.5) and B (14.6); maximum growth rate
occurred at 14.8 weeks. There was no consistent difference between bread and
durum wheat in the partitioning of nutrients to the grain.
The importance of N and Zn uptake to the growth of the durum wheat genotypes
was shown by significant correlations between maximum uptake rates of these
nutrients and maximum crop growth rate, with the strongest correlation being
with Zn. Growth rate was not correlated with uptake rates of other nutrients.
A number of genotypes of durum wheat had maximum rates of Zn and Mn
accumulation up to twice those of the current commercial genotypes. Some of
these lines have yielded well at Zn- and Mn-deficient sites which indicates
that the micronutrient efficiency of durum can be improved.
Late in the season the experiment showed signs of infection by crown rot
(Fusarium graminearum Schw. Group 1). Durum wheat showed
more severe symptoms than bread wheat and the number of white heads in durum
wheat was inversely correlated with the concentration of Zn in the shoot
during the pre-anthesis period.
Effects of chemicals and microbial antagonists on nematodes and fungal pathogens of citrus roots
Authors: Walker G. E. , Morey B. G.
Published: September 2002

In pot and field experiments in naturally infested soil, commercial products
formulated with microbial antagonists, applied to soil, performed poorly
against the nematodes Tylenchulus semipenetrans and
Paratrichodorus lobatus, and the root rot fungi
Phytophthora nicotianae and
Pythium ultimum on citrus, compared with the
conventional chemicals aldicarb, cadusafos and metalaxyl.
Prosper Nema did not reduce nematode levels even when combined with a sawdust
mulch over the soil. Nutri-life 3/20 inhibited citrus growth and caused
leaf chlorosis. Tri-D25 did not reduce root rot or isolation frequency of
Phytophthora nicotianae and
Pythium ultimum. However, a commercial formulation
(Actizyme) of Bacillus subtilis stimulated citrus
growth, and the herbicide oryzalin both stimulated citrus growth and reduced
isolation frequency of Pythium ultimum. Potassium
silicate did not reduce isolation frequency of
Phytophthora nicotianae and
Pythium ultimum or root rot, however, it did reduce
levels of T. semipenetrans in soil. Cadusafos and
aldicarb were equally effective in controlling
T. semipenetrans on roots but cadusafos was more
effective in soil and against Paratrichodorus lobatus.
Aldicarb stimulated citrus growth, while cadusafos plus metalaxyl was more
effective than metalaxyl alone in stimulating citrus growth and preventing
leaf chlorosis in soil infected with
Phytophthora nicotianae.
Results suggested that Phytophthora nicotianae was much
more damaging to citrus than Pythium ultimum, and that
nematodes (in association with Fusarium solani) were
also more damaging than P. ultimum. Relatively low
initial combined levels of T. semipenetrans and
Paratrichodorus lobatus depressed citrus growth;
reproduction rates for P. lobatus exceeded 23-fold the
initial level. Cadusafos (3 applications at 3 g/m2
over 6 months) reduced T. semipenetrans to very low
levels, but did not eliminate the nematode; mechanical incorporation of
nematicide granules improved the level of nematode control after the first,
but not succeeding, applications.
Fungal diseases of temperate annual pasture legumes in southern Queensland
Authors: Mackie J. M. , Lloyd D. L. , Ryley M. J. , Irwin J. A. G.
Published: September 2002

Summary. Diseases of temperate annual pasture legumes in
subtropical southern Queensland were surveyed during 1992 and 1993. The
following pathogenic organisms were recorded:
Colletotrichum trifolii,
Stemphylium vesicarium, Oidium
sp., Uromyces anthyllidis,
Uromyces striatus and
Pseudopeziza medicaginis from annual
Medicago spp.; Rhizoctonia solani
and Colletotrichum destructivum from
Ornithopus spp.; and Oidium sp.
from Trifolium subterraneum. Three of these disease
interactions had not been previously recorded in Queensland and 5 were new
reports for Australia. Rust was the most frequently observed and widespread
disease on annual medics (44% of M. polymorpha
samples). All other diseases of annual medics were found infrequently
(2–18% of samples). In contrast, both serradella and subterranean
clover were relatively free from any diseases.
The years during which the survey was conducted were dry (as low as 31%
of mean March–October rainfall) and the expression of disease may have
been restricted. Nevertheless, this improved knowledge of diseases of
temperate annual legumes in southern Queensland will assist in the future
selection and breeding of suitable cultivars for use in the subtropics.
Establishment, growth and persistence of greater lotus (Lotus uliginosus) at six sites in eastern Australia
Authors: Blumenthal M. J. , Bowman A. M. , Cole A. , Jones R. M. , Kelman W. M. , Launders T. E. , Nicol H. I.
Published: September 2002

Summary. Three Lotus uliginosus populations, cv. Maku,
Sharnae and the line G4704 were compared to
Trifolium repens cv. Haifa on the basis of plant
frequency and contribution to total above ground biomass production at 6 sites
in eastern Australia (Samford, Grafton, Taree, Nowra, Moss Vale and Warragul).
In addition, L. uliginosus G4703 was sown at Nowra and
L. corniculatus (L.) cv. Grasslands Goldie was sown at
Taree. At each site populations were sown with a grass;
Setaria sphacelata cv. Narok at Samford, Grafton and
Taree; Lolium perenne cv. Kangaroo Valley at Nowra and
Moss Vale and cv. Ellett at Warragul. Grasslands Maku and the sown grasses
were also sown alone at each site. Each of the pasture treatments was sown
either with 500 kg/ha single superphosphate or without superphosphate (or
with small amounts of P, if available soil Bray P
The main findings were that: (i) superphosphate had little effect on lotus
frequency and biomass after the first few harvests; (ii) Haifa white clover
was the most successful legume in terms of plant frequency and contribution to
total biomass at the subtropical sites (Taree, Grafton and Samford); (iii)
Haifa was the most successful legume in the establishment year at the
temperate sites, but lotus became dominant in subsequent years; (iv)
Grasslands Maku was the superior greater lotus population in terms of
frequency and contribution to total biomass production at all sites; and (v)
at Taree, the one site where L. corniculatus cv.
Grasslands Goldie was included, it was the superior population.
Changes in soil chemical and physical properties following legumes and opportunity cropping on a cracking clay soil
Authors: Armstrong R. D. , Kuskopf B. J. , Millar G. , Whitbread A. M. , Standley J.
Published: September 2002

Incorporating legumes into the cropping system has been shown to significantly
improve the nitrogen nutrition of cereal crops in Central Queensland. However,
little is known about the effect of these legumes on the chemical and physical
properties of soil. We examined changes in soil chemical (total nitrogen,
organic carbon and pH) and physical (bulk density, cone penetrometer
resistance and saturated hydraulic conductivity) properties following either
continuous cropping (sorghum or mungbean) or pasture legumes (siratro,
lucerne, lablab and desmanthus) over 4 years. Soil carbon was also
fractionated using a KMnO4 oxidation procedure which
classifies the soil carbon into either labile or non-labile pools.
All pasture legumes except desmanthus increased soil total nitrogen in the
topsoil (0–10 cm) after only 2 years compared with sorghum. Total
nitrogen in the soil did not significantly change under mungbean. Soil organic
carbon progressively increased under siratro, desmanthus and sorghum but
remained unchanged under the other legumes. Before the experiment, the
percentage of total soil carbon classified as labile (oxidised by 333 mmol
KMnO4/L) ranged from 14 to 17%. The amount of
labile carbon increased by 17% after 3 years of siratro, remained
unchanged under desmanthus and sorghum, and decreased under the annual legumes
and lucerne. Non-labile carbon remained either unchanged or increased under
all legumes, whereas it tended to decrease after 3 consecutive sorghum crops.
Soil pH was generally highest under sorghum and lowest under lablab. Soil
after sorghum had higher bulk density and penetrometer resistance compared
with the effect of legumes but these differences were comparatively small.
Saturated hydraulic conductivity of the soil was much higher on the soil
surface than at 10 cm. On the surface, soil hydraulic conductivity (saturated)
values were generally lower following siratro and higher after sorghum than
the other species. At 10 cm depth, soil hydraulic conductivity (saturated) was
generally lower in sorghum and, to a lesser extent, in mungbean plots
reflecting the significantly lower density of macropores under these crops.
It was concluded that although all legumes generally enhanced the chemical and
physical properties of the cracking clay, perennial legumes such as siratro
would have a greater beneficial effect in the longer term than annual legumes.
In vitro larvicidal efficacy of flystrike dressings against the Australian sheep blowfly
Authors: Levot G. W. , Sales N. , Barchia I.
Published: September 2002

The abilities of 14 registered flystrike products to prevent development of
Australian sheep blowfly (Lucilia cuprina) larvae were
measured by laboratory bioassay. Larvae were exposed to the products for
periods ranging from 5 to 180 s. Most products were quite effective against
susceptible-strain larvae but less effective in field strains due to
organophosphate resistance. Some products killed fewer than 20% of
field larvae, even after 180 s exposure. However, field strain and
susceptible-strain L. cuprina were equally likely to
succumb after thorough exposure to a powder formulation of diazinon or to
products containing ivermectin or cyromazine. Most products had no obvious
effects on larvae until 2–8 h after treatment. Exceptions were
non-aqueous, ready to use formulations such as Kleendok with diazinon,
Defiance S and Coopers Flystrike Powder. In the cases of Kleendok with
diazinon and Defiance S it is likely that formulation components other than
the active ingredient were responsible for the fast action. Of the aqueous
organophosphate formulation products Supona, containing chlorfenvinphos, was
the fastest acting. Greater proportions of susceptible larvae responded over
time but among field larvae that responded initially, there were some that
recovered within 24 h. Increasing concern over insecticide residues in wool
following jetting (topical treatment) of whole sheep, has placed greater
reliance on dressing products to control flystrike. With so few effective
products available there is a ready market for fast-acting, efficacious
products.
Effect of timing of hand thinning on productivity of Moorpark apricots destined for drying
Authors: Rettke M. A. , Dahlenburg A. P.
Published: September 2002

Summary. Thinning at full bloom was compared with
thinning at 3 stages of fruit development and the effects on size, total
soluble solids level (TSS) and yield of apricots are reported. In 2 seasons
separate branches of 9-year-old Moorpark apricot trees were hand-thinned to a
density of 1 blossom or fruit per 50 mm of fruiting wood. Times of thinning
were at full bloom, 5–15 mm size fruit, stone tip hardening and 21 days
post stone tip hardening. These treatments were compared with an unthinned
control. Experimentation was carried out at Loxton, South Australia. All
thinning treatments reduced the yield of fresh fruit. Thinning reduced yield
of dried fruit irrespective of timing in the first season but only at the
5–15 mm diameter fruit timing in the second season. Total soluble solids
level of the fruit was increased by thinning which tended to improve drying
ratio. Compared to the unthinned control all thinning treatments increased the
size of fresh fruit. Mean fruit weight and diameter progressively decreased as
thinning was delayed from full bloom till stone tip hardening. Thinning at
full bloom produced higher yields of 35-mm-grade dried fruit than other
treatments. To achieve the greatest benefit from thinning it should be carried
out at blossoming.
Assessment of resistance and tolerance of in vitro-propagated banana plants to burrowing nematode, Radopholus similis
Authors: Stanton J. M.
Published: September 2002

Summary. In vitro-propagated
banana plants cv. Goldfinger were not resistant to
Radopholus similis unless they were at least 28 weeks
old at inoculation. By contrast, a Pisang jari buaya clone and SH-3142
expressed resistance when inoculated from 12 and 8 weeks of age respectively.
Fewer nematodes were recovered from older plants of Goldfinger than from
Cavendish 3 weeks after inoculation (i.e. before a life cycle could be
completed). This suggests that the resistance mechanism of Goldfinger involves
reduction in both penetration and reproduction by nematodes. Comparison of
recovery of nematodes following inoculation of plants at different ages showed
that resistance assays should use plants which are at least 28 weeks old.
Also, plants should be at least 28 weeks old when establishing a plantation to
reduce the chance of severe damage by high nematode densities. Goldfinger was
more tolerant to R. similis than was Cavendish when
supporting the same number of nematodes.
Dry matter intake, nutrient selection and milk production of dairy cows grazing rainfed perennial pastures at different herbage allowances in spring
Authors: Moate P. J. , Dalley D. E. , Roche J. R. , Grainger C.
Published: September 2002

Summary. The effect of herbage allowance (20, 30, 40,
50, 60 and 70 kg DM/cow. day) on the consumption of nutrients from herbage
and milk production by cows in early lactation, was examined. The experiment
was conducted on rainfed perennial ryegrass pastures in September and October
1997 in south-eastern Victoria, Australia. The herbage on offer comprised
64% perennial ryegrass, 21% other grasses, 1% white
clover, 5% weeds and 9% dead material on a dry matter (DM)
basis. The average pregrazing herbage height was 13 cm, at an estimated
pregrazing herbage mass of 3.6 t DM/ha. The herbage on offer was of high
quality containing 11.6 MJ metabolisable energy/kg DM, 202 g crude
protein/kg DM and 525 g neutral detergent fibre/kg DM. Concentrations
of calcium, magnesium, sodium, potassium, phosphorus, sulfur and chloride were
4.4, 2.2, 4.4, 31.2, 3.5, 2.7 and 11.4 g/kg DM, respectively.
As daily herbage allowance per cow increased, dry matter intake increased
curvilinearly (P<0.01) from 11.2 to 18.7 kg
DM/cow. day. This was associated with a decrease in utilisation of herbage
from 54 to 26% and an increase in milk production from 25.9 to 29.1
kg/cow. day. The cows on all treatments grazed for less than 8.7
h/day. The increase in intake was achieved by an increase in the rate of
herbage intake from 1.5 to 2.2 kg DM/h for herbage allowances of 20 and 70
kg/cow.day, respectively.
Irrespective of herbage allowance, cows selected a diet that was approximately
10% higher in in vitro dry matter digestibility
and 30% higher in crude protein than that in the herbage on offer. The
neutral detergent fibre content of the herbage selected was lower
(P<0.05) than that on offer. The herbage consumed
contained more (P<0.05) magnesium, potassium and
sulfur, the same amount of calcium and phosphorus and less
(P<0.05) sodium and chloride than the herbage on
offer.
For rainfed perennial pastures in spring, herbage allowance is an important
factor in determining voluntary feed intake and production of dairy cows. To
achieve 30 L from herbage, without supplementation, high herbage allowances
are required. The increase in herbage intake, with increasing herbage
allowance, resulted from an increase in rate of dry matter intake and not an
increase in grazing time. No relationship was evident between herbage
allowance and the selection differentials for in vitro
dry matter digestibility, crude protein and neutral detergent fibre. Selection
differentials for rainfed perennial pastures in spring are similar to those
reported for irrigated perennial pastures in northern Victoria in spring and
autumn. When determining nutrient requirements it is important to consider the
interaction between herbage intake and nutrient concentration in the herbage.
Honeybees (Apis mellifera L.) increase yields of faba beans (Vicia faba L.) in New South Wales while maintaining adequate protein requirements from faba bean pollen
Authors: Somerville D. C.
Published: September 2002

Summary. A trial was conducted to measure the impact of
honeybees (Apis mellifera L.) on faba bean
(Vicia faba L.) yields and to determine the value of the
crop to honeybees.
The seed yield in cages with bees was 25% higher than in those without
bees. The pollen harvested by honey bees from the faba beans met their
nutritional requirements for protein and amino acids but there was no
detectable nectar crop gathered from the faba beans. Thus, there seems to be a
strong case for using managed honey bees to improve pollination and hence
yields of Australian faba beans where feral bee populations maybe
insufficient.
Associations between temperament, performance and immune function in cattle entering a commercial feedlot
Authors: Fell L. R. , Colditz I. G. , Walker K. H. , Watson D. L.
Published: September 2002

Behavioural, endocrine and immunological
measures made at weaning or feedlot entry were examined for associations
amongst them and with feedlot performance with a view to identifying
predictors of the suitability of cattle for feedlot finishing. The 24 animals
used in this experiment were chosen to represent the extremes of temperament
amongst 209 beef steer calves that were weaned at 7–9 months of age.
From a subgroup of 50 animals that were paddock-weaned without handling or
supplementary feeding, the 12 animals with the worst temperament were selected
on the basis of flight time and crush behaviour assessment. From a matched
subgroup of 100 animals that were weaned in yards and hand fed for 10 days,
the 12 animals with the best temperament were selected on the basis of flight
time, crush score and a novel behavioural test performed as follows. Each
morning, fresh hay and a small amount of grain were offered in an adjacent pen
and calves were scored on their willingness to walk past an observer standing
by the gateway between the 2 pens. These 2 experimental groups were designated
as ‘nervous’ and ‘calm’, respectively. Blood samples
were collected at the start and end of weaning for cortisol assay. On entry to
a commercial feedlot 6 months later, blood samples were collected for cortisol
and immunological assays on day 1 (immediately after induction processing) and
day 5 (after 4 days in the feedlot pen). The nervous group had significantly
higher cortisol levels at weaning and at the feedlot and, after 85 days on
feed, had significantly lower average daily gain and significantly higher
morbidity than the calm group. Groups did not differ in total and differential
leucocyte counts, lymphocyte proliferation, production of the cytokine
interferon, natural killer cell activity, neutrophil myeloperoxidase activity,
lymphocyte subsets (CD4, CD8 or WC1), and serum concentrations of IgA, but IgM
was lower in the calm group. Significant correlations were found between
cortisol and a number of haematological variables, flight time, and average
daily gain. The correlations suggest that desirable traits at feedlot entry
may include slow flight time, low crush score and high confidence score, low
cortisol, low total white cell count, low neutrophil count, high CD8 +
lymphocyte percentage, high lymphocyte proliferative activity and high IgA
concentration. Relationships between behavioural traits and immunological
measures may have utility in predicting the suitability of individuals for the
feedlot environment.
Tolerance of cryptic species of blue oat mites (Penthaleus spp.) and the redlegged earth mite (Halotydeus destructor) to pesticides
Authors: Umina P. A. , Hoffmann A. A.
Published: September 2002

Blue oat mites (Penthaleus spp.) and redlegged earth
mites (Halotydeus destructor) are major pests of crops
and pastures in southern Australia. Management of these mites has been
complicated by the recent discovery of 3 cryptic parthenogenic species of
Penthaleus, whereas prior research had assumed a single
species. The response of the 3 Penthaleus species and
H. destructor to commonly used pesticides (omethoate,
methidathion, bifenthrin and endosulfan) was compared.
Penthaleus falcatus was more tolerant of all pesticides
than the other species, whereas H. destructor tended to
be the most susceptible. The response of P. major was
similar to that of an undescribed cryptic species
(Penthaleus sp. x). Mites were
sampled from 7 sites where control failures had been reported. Three of these
failures were due to P. falcatus despite the fact that
this species is relatively uncommon. This suggests that the high tolerance
levels of P. falcatus relative to the other species may
lead to control problems. Nevertheless, samples of
P. falcatus from the control failure sites did not
exhibit a higher level of tolerance than those from an unsprayed site. Clones
of both P. falcatus and P. major
differed in tolerance levels, suggesting some potential for the evolution of
increased tolerance levels in mite populations. The results highlight the
importance of determining species composition when devising control strategies
for mite pest outbreaks.
Plant tests for diagnosing phosphorus deficiency in barley (Hordeum vulgare L.)
Authors: Hoppo S. D. , Elliott D. E. , Reuter D. J.
Published: September 2002

Summary. Six field experiments were conducted in the
Murraylands and Mid North regions of South Australia between 1986 and 1988 to
develop plant tests for diagnosing the phosphorus status of barley. The
effects of applied phosphorus level on total phosphorus concentrations in
youngest emerged leaf blades or whole shoots, and on shoot yield, were
examined and critical ranges were established during vegetative growth.
Experiments were conducted on a range of soil phosphorus levels with several
methods of phosphorus placement and 2 barley cultivars.
During early tillering, shoot yield and phosphorus concentrations in youngest
emerged leaf blades and whole shoots were increased more by drilling
phosphorus fertiliser with the seed (banded) than by spreading the same
phosphorus rate over the soil surface and partially incorporating the
fertiliser while sowing (broadcast). However, these methods of phosphorus
placement did not affect diagnostic relationships between relative shoot yield
and phosphorus concentrations in youngest emerged leaf blades and, as a
result, critical total phosphorus concentrations were similar for both methods
of applying phosphorus fertiliser.
Estimated critical total phosphorus concentrations for both Schooner and
Galleon barley were similar at each sampling time when allowances were made
for minor differences in growth stages between the cultivars; even though
phosphorus concentrations in youngest emerged leaf blades and whole shoots
were higher in Schooner than in Galleon at adequate phosphorus supply.
Between Zadoks scale 13.5 and 16.5 there was a linear decline in critical
total phosphorus concentration in youngest emerged leaf blades with increasing
plant age. A more variable, but steeper, decline was found for critical total
phosphorus concentration in whole shoots. Critical ranges are proposed for
total phosphorus concentrations in youngest emerged leaf blades and whole
shoots of barley.
The decline in critical total phosphorus concentration in youngest emerged
leaf blades with advancing plant age was mainly caused by a higher functional
requirement for phosphorus at early stages of growth and by increasing dry
weight, cellulose and lignin content of youngest emerged leaf blades as plants
age. Changes in the spatial distribution of applied phosphorus in relation to
root growth did not seem to be important.
The effects of monensin on milk production and levels of metabolites in blood and rumen fluid of Holstein-Friesian cows in early lactation
Authors: Granzin B. C. , Dryden G. McL.
Published: September 2002

Summary. Monensin was fed to Holstein–Friesian
cows in early lactation to study its effects on concentrations of blood
metabolites, feed intake, body condition and milk production. In the first
experiment, 18 Holstein–Friesian cows were randomly stratified into 6
similar groups of cows based on parity and previous milk yield. Cows within
these groups were assigned randomly to be fed either 0, 150 or 300 mg of
monensin per day. Monensin was fed as a component of a 1 kg grain supplement
at 0600 h daily from 14 days prepartum to 84 days postpartum.
Mean milk yields (kg/day) of cows supplemented with monensin at 150
mg/day (23.0) and 300 mg/day (23.7) were significantly higher
(P<0.05) than those of unsupplemented cows (21.1).
Milk fat and protein contents were not affected by monensin feeding but daily
yields of milk fat and protein differed significantly
(P<0.05) between treatments. Monensin supplemented at
300 mg per day significantly (P<0.05) reduced the
molar proportion of rumen acetate and increased the molar proportion of rumen
propionate. Monensin fed at either 150 or 300 mg/day significantly
(P<0.05) increased the ratio of plasma glucose:
β-hydroxybutyrate (BHB), but had no effect on concentrations of blood
acetoacetate, serum nonesterified fatty acids (NEFA), plasma glucose or BHB.
Monensin had no effect on liveweight change or condition score.
In the second experiment, 12 Holstein–Friesian cows in early lactation
were blocked on parity into 3 groups of 4 cows, and 2 cows within each block
were of either high, or low genetic merit. Monensin (none or 320 mg per day)
and genetic merit were assigned as a 2 by 2 factorial arrangement of
treatments. Monensin supplementation commenced 28 days prepartum and ended 56
days postpartum. Monensin caused a significant
(P<0.05) increase in feed intake (21.6
v. 23.2 kg/day) and significantly reduced plasma BHB
concentration (64.0 v. 6.7 mg/dL). Cows with a
higher genetic merit had a significantly (P<0.05)
higher milk yield (27.2 kg/day) compared to cows of low genetic merit
(26.3 kg/day). Low genetic merit cows fed monensin had significantly
(P<0.05) lower daily milk fat yield, lower serum NEFA
concentration and higher plasma glucose concentration compared to low genetic
merit cows not fed monensin, or high genetic merit cows. Serum insulin and
bovine somatotrophin concentrations were unaffected by the treatments.
The results of these experiments suggest that with Holstein–Friesian
cows in early lactation, the increase in hepatic propionate supply caused by
monensin supplementation increases glucose synthesis and subsequent milk
production when the requirements of the mammary gland for glucose are not
otherwise being met. If the glucose requirements of the mammary gland are
being satisfied, monensin decreases ketogenesis and the mobilisation of
adipose tissue. Monensin had a positive effect on intake in this study.
Freeze-induced reduction of broccoli yield and quality
Authors: Tan D. K. Y. , Joyce D. C. , Wearing A. H. , Rickert K. G. , Birch C. J.
Published: September 2002

Summary. Sub-zero temperatures can result in freezing
injury of broccoli (Brassica oleracea L. var.
italica Plenck) plants and thereby reduce head yield and
quality. In order to predict effects of frosts, it is desirable to know the
stages of development at which broccoli plants are most susceptible to
freezing injury. In this study, the effect of a range of sub-zero temperatures
for a short period at different stages of crop development were assessed and
quantified in terms of mortality, yield and quality of broccoli. Whole plants
in pots or in the field were subjected to sub-zero temperature regimes from
–1 to –19°C. Extracellular ice formation was achieved by
reducing temperatures slowly, at –2°C per hour. The floral
initiation stage was most sensitive to freezing injury, as yields (fresh and
dry head weights) were significantly reduced at –1 and –3°C,
and the shoot apices were killed at –5°C. There was no significant
yield reduction when the inflorescence buttoning stage was treated at –1
and –3°C. Although shoot apices survived the –5°C
treatment at buttoning, very poor quality heads of uneven bud size were
produced as a result of arrested development. The lethal temperature for
pot-grown broccoli was between –3 and –5°C, whereas the lethal
temperature for field-grown broccoli was between –7 and –9°C.
The difference was presumably due to variation in cold acclimation. Freezing
injury can reduce broccoli head yield and quality and retard plant growth.
With regard to yield and maturity prediction, crop development models based
only on simple thermal time without restrictions will not apply if broccoli
crops are frost damaged.