bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative productivity of super-fine Merino and Border Leicester breeding ewes grazing semi-improved native pasture on the New England Tablelands, New South Wales
Authors: Sumner RMW , Stephenson SK
Published: March 2005

Age-balanced breeding flocks of 40 ewes of the super-fine Merino (M) and Border Leicester (BL) breeds were set-stocked together on semi-improved native pasture for three years. The M ewes grew more wool and weaned more lambs of a lighter weight, while the BL ewes were heavier than the M ewes at all weighings. During the last year the BL ewes experienced an overall weight loss not shown by the M ewes, which was reflected in increased mortality. Mortality within the BL breed was high, 70% compared with 17.5% for the M. Pneumonia was the primary cause of death.
Survival feeding of pregnant and lactating ewes with combinations of wheat and lucerne hay
Authors: Clements BW , Gleeson AR , Nicholls PJ
Published: March 2005

An experiment was performed to determine the proportion of roughage required by pregnant and lactating ewes fed wheat-based diets under drought conditions. Five dietary treatments ranging from wheat alone to lucerne hay alone were fed to pregnant and lactating Merino ewes, at levels estimated to give a similar net energy intake per ewe per day. The energy levels fed were altered during the experiment in an attempt to maintain ewe liveweight at a constant level. Wheat alone was unsuitable for lactating ewes, while a diet of 54% hay and 46% wheat (54:46) gave the best milk yields, lamb growth and lamb survival. The mean milk yields of the ewes ranged from 26.5 � (SD) 2.5 ml hour-1 for wheat alone to 38.1 � 2.2 ml hour-1 for the 54:46 diet. Lamb liveweight gains between birth and weaning (at seven weeks) were related to ewe milk yields, with lambs on the wheat alone diet gaining 3.17 kg and those on the 54:46 diet gaining 5.10 kg. Only half of the lambs born to ewes fed wheat alone survived to weaning, compared with 89% of lambs on the 54:46 diet. Analysis of the responses indicated that, for milk yield, the 54:46 diet was near optimum and that lamb growth and survival would be maximized at 60-67% hay.
Effect of topdressed phosphorus fertilizer on established white clover based pastures in south-east Queensland. 1. Prediction of yield responses using soil tests
Authors: Rayment GE , Bruce RC
Published: March 2005

Seventeen short-term field experiments were conducted over a five year period in south-east Queensland in which rates of up to 60 kg P ha-1 as monocalcium phosphate were topdressed onto established, previously grazed, grass-white clover (Trifolium repens) pastures, Increases (P < 0.05) in yields of white clover were obtained at seven sites, but concurrent increases in grass production occurred at only four sites. Higher total pasture production resulted at six of these sites. One quantitative (total) and two empirical (0.005 M H2SO4 and 0.5 M Na HCO3) estimates of phosphorus status in 0-10 cm soil samples, collected prior to topdressing treatments, were separately correlated with relative yield responses of white clover, grass and total pasture components. Although soil phosphorus levels by all methods were statistically intercorrelated (P < 0.01), acid-extractable and total phosphorus tests were generally unsuitable for predictive purposes, having low coefficients of determination for regressions and Cate-Nelson separations of responsive from non-responsive sites. Bicarbonate-extractable phosphorus proved the most suitable soil test. It accounted for 60 and 44% of the variance in relative yields of white clover and total pasture, respectively, but was poorly correlated with relative yields of grass. The suggested critical level of soil phosphorus (bicarbonate extraction) for white clover is 28 ppm P. For total pasture, responses are likely below 22, unlikely above 28 and uncertain between 22 and 28 ppm P, respectively. Percentage variance in relative yields already explained by both empirical tests was not significantly increased by inclusion of terms for pH and exchangeable calcium into the X variable.
Effect of topdressed phosphorus fertilizer on established white clover based pastures in south-east Queensland. 2. Macronutrient status and prediction of yield responses using plant chemical tests
Authors: Rayment GE , Bruce RC
Published: March 2005

Details are given on the effect of topdressed phosphorus, at rates up to 60 kg P ha-1, on macronutrient concentrations and phosphorus uptakes of components of white clover based pastures from phosphorus responsive and non-responsive sites. These data were obtained from 17 short-term field experiments conducted over a five year period in south-east Queensland. Plant indices for predicting yield responses to phosphorus by these pastures were derived from nutrient concentrations in tops and in 'diagnostic' samples of white clover collected during spring to early summer. Mathematical approaches used had little effect on critical values obtained. For white clover tops, which comprised fresh leaves, petioles and flowers, a critical phosphorus concentration of from 0.28 to 0.30% was established. Alternatively, an N : P ratio of 15 effectively separated responsive from non-responsive sites. The critical phosphorus concentration based on 'diagnostic' samples, which differed from tops in that flowers were excluded, was 0.30%. There was no practical difference between diagnostic indices based on white clover or total pasture production.
Effects of time and rate of application of herbicides on serrated tussock (Nassella trichotoma) and improved pasture species. 2. Tetrapion
Authors: Campbell MH , Gilmour AR , Vere DT
Published: March 2005

The effects of time and rate of application of tetrapion on burnt and unburnt serrated tussock, growing with and without improved species, were measured in four experiments carried out near Bathurst, New South Wales, between 1975 and 1978. Tetrapion proved effective in killing unburnt serrated tussock when applied in each season of the year. The most economical rates proved to be 1.00 kg a.i, ha-1 in spring and summer and 1.33 kg a.i. ha-1 in autumn and winter. Tetrapion was also effective in killing serrated tussock that had been burnt six and nine months before spraying. Although tetrapion had harsh phytotoxic effects on Phalaris aquatica and Trioflium repens growing in association with serrated tussock, these improved species recovered. Thus it proved possible to selectively remove serrated tussock from P. aquatica and T. repens by using tetrapion. Based on 1979 costs, tetrapion appears an economic alternative to other herbicides currently used to kill serrated tussock.
An assessment of whether energy was the first factor limiting production of dairy cows grazing kikuyu grass pasture
Authors: Moir KW , Dougherty HG , Goodwin PJ , Humphreys FJ , Martin PR
Published: March 2005

Whole plants of kikuyu grass were taken at intervals over a 9-month period from four commercial dairy farms on which this grass was the predominant species. The plants were separated into leaf and stem fractions and their metabolizable energy (ME) concentrations were estimated from their cell-wall contents. The overall mean ME in the dry matter of leaf and stem on each farm was of the order of 11 and 9 MJ kg DM-1, respectively. From considerations of appetite limits depending upon whether energy was derived mainly from leaf or stem, and taking into account ME supplied from supplementary feeds, and ME requirements for milk production, it was concluded that the production of the herd with the highest mean production cow-1 (4140 kg lactation-1) was limited by dietary energy concentration, although the genetic capacity of the cows to produce milk at the expense of body weight loss overcame this limitation to some extent. On the other farms with low to intermediate levels of productivity, the amount of food on offer was the first limiting factor.
Effects of multiple suckling by dairy heifers for short periods before and after calving on subsequent milk yields
Authors: Peel CJ , Robinson IB , McGowan AA
Published: March 2005

The effects of multiple suckling by dairy heifers for short periods both before and after calving on milk production were studied. Results from heifers sucked by three calves per heifer for 1, 2, 3 and 4weeks after calving were pooled and a regression equation derived. This predicts that for each additional week that heifers are sucked in early lactation (up to 4 weeks), the post-suckling milk yield will be increased by 4.3 � 0.8% (mean � standard error) compared with similar heifers machine milked from the commencement of lactation. The sucking of heifers before calving did not enhance post-partum milk yields. However, the sucking of heifers for short periods after calving by calves that are being reared as dairy replacements offers a practical means of both increasing milk production, and possibly reducing the labour input of rearing the calves.
Growth and yield of a semi-dwarf and a standard height wheat cultivar in the Murrumbidgee Irrigation Area
Authors: Cooper JL
Published: March 2005

A semi-dwarf cultivar (WW 15) and a standard height Australian wheat variety (Timgalen) were grown at two nitrogen levels and under three irrigation regimes in the Murrumbidgee Irrigation Area. Numerous plant measurements were taken to determine which attributes were associated with the superior yield of semi-dwarf wheat in this environment. WW 15 yielded 42% more grain than Timgalen and nitrogen fertilizer increased the yield of both varieties. The irrigation treatments did not affect yield because rainfall was above average. Total dry matter production and leaf area of WW 15 were similar to those of Timgalen, but WW 15 put a much greater proportion of its dry matter into grain. A greater number of grains per spike was the yield component responsible for the higher yield of WW 15. The increase in grain yield with the addition of nitrogen fertilizer was due to a general improvement in all aspects of crop vigour (e.g. tiller density, leaf area, total dry matter). There was no interaction between cultivars and nitrogen rates in their effect on grain yield.
Agents of pollination in sunflower crops on the central Darling Downs, Queensland
Authors: Radford BJ , Nielsen RGH , Rhodes JW
Published: March 2005

Honeybees (Apis mellifera L.) were the most frequent insect visitors to flowering sunflower heads on the central Darling Downs. Populations in 42 crops during mid-morning in fine weather averaged 65.3 bees per 100 flowering heads. A range of moth species was observed at night but total moth populations in 33 crops between 7 p.m. and 8 p.m. averaged only 3.9 moths per 100 flowering heads. Although Heliothis armigera moths and wind can pollinate sunflowers, insects other than honeybees, and wind, played an insignificant role in crop pollination.
Amelioration of structurally unstable grey soils in the north-western wheat belt of New South Wales
Authors: Doyle AD , Tayler DW , Yates WJ , So HB , McGarity JW
Published: March 2005

Methods of amelioration of structurally unstable grey clays were studied in field experiments conducted at three sites in the Gwydir Valley in northern New South Wales. A set of ameliorative treatments was established at each site in 1973, and a second set of treatments was established in 1974. Plots were sown with wheat each year until 1977 to study residual effects. In the first series of experiments, gypsum at 12.5 t ha-1 greatly increased wheat yields at all sites, with residual effects still strongly evident in 1977. The yield increases were commonly associated with reduced surface soil crust strength, increased wheat establishment, and increased stored soil water at sowing. Potassium sulphate at 3.75 t ha-1 and organic matter (chopped hay at 12 t ha-1) gave initial yield increases, but residual effects did not persist. Neither polyvinyl alcohol (200 kg ha-1) nor deep ploughing (to 25 cm) was successful as an ameliorant. In the second series of experiments, gypsum at 2.5 t ha-1 consistently increased wheat yields, with residual effects still evident in 1977, although yield increases were much less than those obtained with 12.5 t ha-1 gypsum in the first series of experiments. A crop of oats ploughed under was not a successful ameliorant, but calcium carbonate (5 t ha-1) showed some potential.
A re-evaluation of the effectivenes of calcined Christmas Island C-grade rock phosphate
Authors: Palmer B , Bolland MDA , Gilkes RJ
Published: March 2005

The influence of calcination temperatures up to 1050�C on the effectiveness of Christmas Island C-grade ore was determined in glasshouse trials with wheat. All calcines were capable of supporting the same maximum yield. Maximum effectiveness, equivalent to one-third that of superphosphate, occurred for calcination temperatures between 450�C and 600�C. Re-evaluation of the results of other workers indicated that a similar value for relative effectiveness applies to their work on a variety of species.
Control of root-knot of tobacco with ethylene dibromide in north Queensland
Authors: Broadley RA
Published: March 2005

Treatment of a coarse sandy soil with a moisture content of 2.6% (dry weight) with ethylene dibromide (EDB) at 72 kg a.i. ha-1 gave good control of the root-knot nematode, Meloidogyne javanica. Efficacy was not increased when soil moisture was increased to 4.9%, nor by sealing the surface with a roller and irrigation immediately after fumigation. Methods of placement of EDB and dosage rates were compared in three seasons. When applied through one tine at 18 kg a.i. ha-1, nematode control after harvest was slightly inferior to applications of 36 kg through two tines or 72 kg through four tines, but yields of cured leaf and plant girth were not reduced. When EDB was applied through two tines, nematode control improved as the rate of application was raised through the range 18, 24, 30 and 36 kg a.i. ha-1.
Control of root-knot of potatoes on the Atherton Tablelands, north Queensland
Authors: Broadley RA
Published: March 2005

Ethylene dibromide at 72 kg a.i, ha-1, fenamiphos at 10 kg a.i. ha-1 overall or at 5 kg a.i, ha-1 in a band, reduced the incidence of nematode-galled tubers, resulting in increased yields of saleable tubers of up to 225% in a December planted crop and 33% in a January planted crop. Spraying fenamiphos on the soil before planting was more effective than a granule treatment or a post-plant spray. In a crop planted in March, tuber galling was negligible.
Superphosphate and stocking rate effects on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 5. Bone phosphorus levels in grazing cattle
Authors: Little DA , Shaw NH
Published: March 2005

The influence of fertilizer on bone phosphorus levels in grazing cattle was examined on native spear grass (Heteropogon contortus) pastures in central coastal Queensland oversown with Townsville stylo (Stylosanthes humilis). The first experiment compared superphosphate at nil, 125 or 250 kg ha-1 annually (F0, F1, F2, respectively), at three stocking rates. In the eighth and final year of this experiment, bone samples from Brahman-cross cattle obtained by rib biopsy were analyzed for their phosphorus content. Analyses of pasture samples indicated that Fo provided a diet deficient in phosphorus, but that F1 and F2 were adequate. Animals on F0 grew slowly, and after one year bone from the twelfth rib contained 121.5 mg P cm-3 In contrast, bone samples from cattle on F1 and F2 contained over 150 mg P cm-3 . At the end of the year there was no difference in bone phosphorus levels between animals on F1 and F2, although a significant advantage of F2 over F0 became apparent earlier in the year than that for F1. It is suggested that levels around 120 mg P cm-3 in bone from the twelfth rib indicate a deficiency of phosphorus, and that levels over 150 mg P cm-3 indicate adequacy. The diet selected from F0 was apparently deficient in protein for six months of the year. However, the quality of herbage selected from the fertilized pasture was much higher throughout the year, probably mainly through the consequent availability of much greater amounts of Townsville stylo. A second experiment, involving potassium fertilizer plus superphosphate, was run for three years following the development of potassium deficiency in the legume. During the first two years only small changes in bone phosphorus were observed, but in the third year, highly significant increases in bone phosphorus occurred in all fertilizer treatments. In a third experiment, changes in bone phosphorus were measured in animals grazing pasture dressed with superphosphate for the first time. After the first year, F2 produced higher levels of bone phosphorus than did F1, but no difference occurred in the second year. The results suggested that for the promotion of bone phosphorus storage, the higher rate of fertilizer application was of only short-term advantage.
Growth and carcase characteristics of Simmental × Friesian and Friesian × Friesian cattle in a Mediterranean environment
Authors: Gifford DR , Stephen PC
Published: March 2005

The calving performance of 152 Friesian cows, located on two properties in the southern Adelaide Hills region of South Australia and mated to Simmental and Friesian sires, is reported. The growth of their steer and heifer progeny and the carcase characteristics of the steer progeny are also reported. Differences due to breed of sire in the incidence of both assisted calvings and calf deaths at birth were not significant on either property. The number of assisted calvings ranged from 1 in 36 calvings for Friesian x Friesian to 3 in 31 calvings for the Simmental x Friesian, both recorded on the same property. The Simmental x Friesian progeny were always significantly heavier at birth than the Friesian progeny. On one property, the Simmental x Friesian and Friesian x Friesian steers grew at a similar rate from weaning at approximately 11 weeks of age until slaughter at approximately 32 months of age, at which stage their carcases did not differ significantly in weight, length, fat cover and eye muscle area. On the other property, the Simmental x Friesian steers grew significantly faster from weaning to slaughter than did the Friesian x Friesian steers. When slaughtered at approximately 34 months of age, the Simmental x Friesian carcases were heavier (P < 0.001 ) and had a larger eye muscle area (P < 0.001 ) than the Friesian x Friesian steers, but there were no significant differences in length or fat cover. The carcases of both breed types were leaner than required by the local Adelaide market and steers would need to be slaughtered at heavier liveweights than those used in this study for acceptable levels of carcase fatness to be achieved.
Effect of shearing time and location on vegetable matter components in the New South Wales woolclip
Authors: Warr GJ , Gilmour AR , Wilson NK
Published: March 2005

Four shearing times, summer, autumn, winter and spring, were examined in relation to the quantity and type of vegetable fault in Merino wool in seven districts of New South Wales in 1974 and 1975. Shearing time did not affect total vegetable matter (VM) content in six of the seven districts surveyed. Shearing in summer in the Central-West Slopes and Plains lowered (P < 0.05) VM compared with autumn and winter shearing; levels of burr and seed were also lower (P < 0.05). In other districts, burr or seed components were decreased at particular times of shearing, but there was no effect on total VM content. Seed contamination was lowest with spring and summer shearing in all districts in survey 1. Thus, in most districts, shearing time did not reduce VM, but in particular areas such changes may be of considerable value in reducing contamination from individual species. Wools from the North-West Slopes and Plains, Central-West Slopes and Plains and Western Division were heavily contaminated with burr and seed, whereas in wools from the Tablelands and Southern Slopes, seed was the major contaminant.
Effect of selenium supplementation on survival, liveweight and wool weight of young sheep on Kangaroo Island, South Australia
Authors: Walker SK , Hall GP , Smith DH , Ponzoni RW , Judson GJ
Published: March 2005

The responses in liveweight, wool weight and survival, to selenium supplementation, were studied in young sheep from weaning to yearling age. The experiment was conducted over three years. In the first year, one sodium selenite supplementation rate was used (total dose 46.5 mg). During the following two years two supplementation rates were administered (total doses 46.5 mg and 93 mg). Mean concentrations of selenium in whole blood in unsupplemented sheep varied from 0.19-0.56 pmol l-l and from 0.20-0.44 pmol l-1 in the two years in which concentrations were measured. Supplementation, which commenced at lamb marking, increased the selenium concentration in sheep at weaning and thereafter. Selenium supplementation improved the break-of-season weight (P < 0.01) and yearling weight (P < 0.01 ) but not weaning weight (0.05 < P < 0.1 ). Hogget fleece weight was improved (P < 0.01 ) and mortality reduced (P < 0.01) by selenium supplementation. There was a treatment x year interaction in mortality rates (P < 0.01 ). There were no significant differences between the two supplementation rates
Reducing losses of surface-sown seed due to harvesting ants
Authors: Campbell MH , Gilmour AR
Published: March 2005

Four experiments were carried out at Orange, New South Wales, in 1978 to test the effect of coating seeds with insecticides on their removal by seed harvesting ants (Pheidole sp.). Treated or untreated seeds of Phalaris aquatica were placed 10 cm from the entrance to an ant nest and the number of seeds taken by ants noted daily. Further experiments tested the effect of coating seeds with insecticides on the germination of P. aquatica and Medicago sativa and on the viability of rhizobia applied to the seed. Permethrin, at 1.50 and 2.25 g a.i. kg-1 seed and bendiocarb at 0.75, 1.50 and 2.25 g a.i. kg-1 seed significantly reduced the rate of removal of seed by ants when compared with the rate of removal of untreated seed. Ants removed untreated seed at > 150 seedsinest day-1 while treated seed was removed at an average of 5 seedslnest day-1 over a 14 day period. The wettable powder formulation of permethrin was as effective as the miscible oil formulation. The activity of ants from nests that took treated seed was reduced by the higher rates of bendiocarb, but not affected by permethrin and the low rate of bendiocarb when compared with the activity of ants from nests that took untreated seed. The miscible oil formulation of permethrin reduced the rate of germination of P. aquatica, but the wettable powder formulation of both permethrin and bendiocarb had no deleterious effect on germination. Neither permethrin nor bendiocarb had deleterious effects on the survival of Rhizobium meliloti or R. trifolii.
Economic and biological factors determining productivity in a young hedgerow planting of apples
Authors: Beattie BB , Campbell JE , Roberts EA
Published: March 2005

Data for the first eight years of a planting of Jonathan, Delicious and Granny Smith apples on MM.102, MM.104, MM.106 and Northern Spy (NS) rootstocks are considered. Spacings of 3.7 m (440 trees ha-') to 1.9 m (862) in steps of 0.15 m were used in rows 6.1 m apart. Trees were pruned to a central leader. Jonathan, Delicious and Granny Smith on NS and MM.106 rootstocks produced bigger trees at the wider spacings, as did Granny Smith on MM.104 and Delicious on MM.102; the size of Granny Smith and Jonathan trees on MM.102, and of Delicious on MM.104, was not affected by spacing ; Jonathan on MM.104 produced the biggest trees at the closer spacings. Yield per tree was not affected by spacing. Granny Smith gave highest yield over the period, followed by Delicious; for rootstocks the order was NS, MM.106, MM.104 with MM.102 last. Commercial quantities of fruit were produced after four years and a total of around 80 t ha-' was produced between ages four years and eight years from trees planted 3.7 m apart. Trees planted 1.9 m apart produced around 130 t ha-l over the same period. The quality of fruit from the trial was comparable with commercial fruit, and there were no apparent differences in quality between fruit from densely spaced and from widely spaced trees. After taking into account costs of production such as sprays, fertilizer and labour, and estimated market price, the approximate cumulative net returns per hectare over the five years were : $7420, $11,540 and $12,390 � $440 for Jonathan, Delicious and Granny Smith cultivars. For rootstock net returns were $781 0, $831 0, $1 2,500 and $1 3,200 � $500 for MM.102, MM.104, MM.106 and NS. Net returns increased by $326 � $68 for each 0.1 5 m unit decrease in spacing. These results indicate that apples planted at higher densities than normal and pruned to a central leader are far superior to the current Australian apple plantings in yield per hectare and in productivity.
The growth rates of weaned lambs grazing three legume-based pastures during summer
Authors: Sanderson ID , McFarlane JD , McManus WR
Published: March 2005

An experiment was conducted on the Central Western Slopes of New South Wales with Dorset Horn x Merino lambs to assess their liveweight gains during summer when weaned on to a lucernebased pasture under dryland conditions, and when weaned on to irrigated lucerne and red clover pastures. Lambs grazing irrigated lucerne, irrigated red clover and dryland lucerne had average growth rates of 155, 178 and 124 g day-1/head, respectively, throughout the 106 day experimental period. The poor growth rates of lambs on the dryland lucerne were apparently due mainly to the low digestibility of the dry feed on offer as a result of low rainfall, which also caused feed supply to be limiting during part of the experimental period. Lamb growth and intake data suggest that the diets selected from the red clover were of higher digestibility than those selected from the irrigated lucerne. It was concluded that irrigated red clover and irrigated lucerne provided useful diets for young lambs in this environment, although the growth rates achieved were less than reported elsewhere for these species in cooler climates. Growth rates achieved by lambs grazing dryland lucerne were less satisfactory for prime lamb production.
Zinc status of grazing sheep: seasonal changes in zinc concentrations in plasma, wool and pasture
Authors: Masters DG , Somers M
Published: March 2005

Zinc status of grazing sheep was surveyed for three years on six properties in the south-west of Western Australia. The concentration of zinc in the plasma of rams and ewes varied both among sheep and among properties, and was up to 21% lower in autumn than in spring. The zinc status of ewes, but not rams, remained low in winter, as reflected by both plasma and wool levels. Pasture zinc levels were lowest in autumn and highest in winter, and regular recordings below 20 �g g-1 were made. The low zinc status of sheep in autumn was accompanied by low pasture zinc content and a low pasture availability. However, the data suggest that the decrease in maternal zinc levels during winter are due to reproductive stress. Plasma zinc levels regularly fell below the presently suggested optimum, and seasonal variation in both plasma and wool zinc levels indicates that in autumn and possibly winter there is an inadequate uptake of zinc. This is indirect evidence for a widespread marginal deficiency of zinc in grazing sheep.
Evaluation of pigeon pea (Cajanus cajan) as an autumn forage for coastal New South Wales
Authors: Norman MJT , Searle PGE , Dankittipakul N , Ingram KC , Baskoro Jde B
Published: March 2005

Six experiments were carried out at Camden, New South Wales (latitude 34�S), over 5 years, 1973-74 to 1977-78, to evaluate pigeon pea as a potential annual legume forage for autumn use in coastal New South Wales. Three cultivar tests were made with a limited range of material from the University of Queensland collection. The cultivars UQ38 and UQ50 were the most satisfactory. A plant population study with UQ38 and UQ50 gave population response curves for total dry matter yield of the form Y = a-bcx, with near maximum yields at 5-6 plants m-2. A time of sowing experiment with UQ50 indicated that to achieve maximum leaf yield at the end of April, sowing could be made as late as early November. A defoliation study with UQ50 showed pigeon pea to be susceptible to mid-season cutting: minimum total yields (first cut plus recovery) were obtained by cutting 12 or 15 weeks after sowing. Two experiments involving periodic sampling in autumn and early winter, together with results from the defoliation study, indicated that pigeon pea could only be utilized satisfactorily for grazing from March to May inclusive. It is concluded that pigeon pea has some potential as an autumn forage. Its main disadvantages are the need for high weed control inputs, a consequence of its slow early growth, and the limited period over which it could be usefully grazed.
Effect of wheat seeding rate on wild oat competition
Authors: Radford BJ , Wilson BJ , Cartledge O , Watkins FB
Published: March 2005

A series of field trials was sown on black earth soils on the Darling Downs, Queensland, with five wheat seeding rates x five levels of wild oat infestation. The lowest seeding rate required to produce optimum grain yield at a site was higher in wild oat infested plots than in weed-free plots. Increase in seeding rate reduced the dry weight of wild oats at maturity and increased the dry weight of wheat at maturity until wheat population density exceeded 150 plants m-2. Increase in seeding rate also reduced wild oat seed production, especially at low wild oat population densities.
Survival in soil of bacteria causing common and halo blights of French bean in Victoria
Authors: Wimalajeewa DLS , Nancarrow RJ
Published: March 2005

Survival of Pseudomonas phaseolicola and Xanthomonas phaseoli in soil between successive bean crops was studied in a field situation at Bairnsdale. P. phaseolicola and X. phaseoli survived on nylon netting for maximum periods of 6 and 3 weeks, respectively, on the soil surface, and for 6 and 2 weeks when buried. On infected leaf, stem and pod tissue P. phaseolicola survived for 20 weeks on the soil surface and for 11 weeks when buried; X. phaseoli survived up to 11 weeks on the soil surface and for 3 weeks when buried. In heavily infected bean plots neither pathogen was carried over from one growing season to the next. It is concluded that infected bean debris in the soil from the previous growing season is not a source of common and halo blight infection in East Gippsland.
Indexing grapevine clones in the Fruit Variety Foundation of Australia for virus and virus-like diseases
Authors: Shanmuganathan N , Fletcher G
Published: March 2005

Using a wide range of indicators, 94 grapevine clones held in the national repository at Irymple, Victoria, were indexed for the important virus and virus-like diseases of grapevine during 1974 to 1979. Results showed that 12 clones were infected with leafroll, 53 with yellow speckle and 4 with fleck. The clones appeared to be free from asteroid mosaic, corky bark, legno riccio, flavescence doree, fanleaf and other soil-borne virus diseases.
Fungicidal control in pineapple and avocado of diseases caused by Phytophthora cinnamomi
Authors: Allen RN , Pegg KG , Forsberg LI , Firth DJ
Published: March 2005

Root and heart rot diseases of pineapples and root rot of avocado caused by P. cinnamomi were controlled with fungicides. In pineapples, treatments were applied at planting and again after one and two months. Ridomil (0.8 kg a.i. ha-1) and Aliette (8 kg a.i. ha-1) controlled P. cinnamomi better than the standard Difolatan treatment (11 kg a.i. ha-1). In avocado nursery plants, Ridomil mixed with the soil before planting (1 g a.i. per 10 l soil) or drenched onto the soil surface around established plants (1 g a.i, per 10 1 container) controlled root rot for at least four months after treatment. Two applications of Ridomil, applied at a rate of 5 g a.i. m-2 as a soil drench beneath the canopy of 7 year old trees affected by root rot, controlled P. cinnamomi without affecting its biological antagonists and permitted trees to recover over a 12-month period.
Reduction of red colour in Starkrimson apples using calcium nitrate sprays
Authors: Jones KM
Published: March 2005

Experiments were conducted for two years in Southern Tasmania on Starkrimson apple trees in an attempt to lighten the unacceptable dark red colour of the fruit. Treatments consisted of spraying trees with zero (control), two, four, six and eight sprays of 0.5% w/w calcium nitrate. Sprays were applied at weekly intervals, each treatment being completed one week prior to a common harvest date. In both years calcium nitrate reduced red colouration, the magnitude of the reduction was dependent on the number of sprays. In 1976 the proportion of unacceptable apples was reduced from 40% to 13% by eight sprays of calcium nitrate. The proportion of unacceptable fruit was further reduced from 13% to 1% during cold storage and ripening. Colour did not develop strongly in 1977 and although the effects of calcium nitrate sprays and storage plus ripening were to reduce red colour they were of no practical significance. A further experiment in 1977 tested the effect of increasing the concentration of calcium nitrate from 0.5% to 1.0% and 1.5% w/w, in an effort to reduce the number of sprays. No significant colour reduction resulted from these treatments. Yield was not significantly affected by any treatment. Calcium nitrate sprays reduced the incidence of breakdown in the 1976 trials at the higher number of applications, but no difference was detected in 1977.
A comparison of two methods of predicting bone weight of cattle
Authors: Murray DM
Published: March 2005

The accuracy of some published prediction equations for two methods of predicting side bone weight of cattle was evaluated by fitting data from cattle of known carcase composition to them. The two methods evaluated are based on the use of either side weight and the weight of the radius and ulna; or the separate weights of the humerus, radius and ulna, femur and tibia. The results indicated that of the two methods, the use of the weights of the four bones gave by far the more accurate results when applied to the independent sample of test data. Some data of other workers relating to the use of the radius and ulna as a predictor of side bone weight are reported. These data suggest that the relatively poor results obtained here for the method incorporating the weight of the radius and ulna may not necessarily reflect the possible predictive value of this bone.
Use of carcase measurements to predict percentage carcase composition in crossbred lambs
Authors: Thompson JM , Atkins KD
Published: March 2005

Half carcases from 108 lambs, from two sexes (wethers and ewes), six genotypes (Dorset Horn and Border Leicester rams crossed with Merino, Corriedale and Border Leicester x Merino first cross ewes) and three slaughter weights (34, 44 and 54 kg liveweight) were dissected into fat, muscle, bone and connective tissue. Measurements of carcase weight, fatness (1 2-13th and 8-9th rib fat depth), size (carcase length, chest depth and leg length) and shape (fleshing index) were recorded. Carcase weight and fat depth at the 12-13th and 8-9th rib sites were the three best single predictors of percentage fat (RSD's = 3.564,3.912 and 3.291 ), percentage muscle (RSD's = 3.1 64,2.970 and 2.948) and percentage bone (RSD's = 1.455, 1.848 and 1.467) in the carcase. The combination of carcase weight with a measure of fat depth at the 12-13th or 8-9th rib sites improved the prediction of percentage fat (RSD's = 2.845 and 2.955), percentage muscle (RSD's = 2.629 and 2.851) and percentage bone (RSD's = 1.425 and 1.342) over that of carcase weight or fat depth as single predictors (P< 0.05). The further addition of size or shape to a model already containing weight and fatness was not significant (P > 0.05). Interactions between carcase measurements and weight were significant for some measures of fatness and size in the prediction of percentage fat and bone. No interactions were significant in the prediction of percentage muscle. The effect of genotype on the prediction of percentage composition was significant for many of the measurements, whereas the effect of sex was only significant for prediction of percentage bone and not for prediction of percentage fat and muscle. It was concluded that carcase weight and fatness provided the most accurate prediction of percentage carcase composition and that additional measures of size or shape did not improve the accuracy. Using carcase weight and fatness, knowledge of genotype improved the prediction of percentage carcase composition, whereas sex was relatively unimportant.
A study of the periods for which lupin stubbles infected with Phomopsis leptostromiformis remain toxic
Authors: Allen JG , Wallace SR , Wood PM
Published: March 2005

The toxicity of the stubbles of a number of lupin crops was monitored throughout summer and autumn in 2 years. It was shown that lupin stubbles can be toxic at the time of harvest, that they can remain significantly toxic for at least 17 weeks, and that toxicity can develop in the absence of summer rain. On the basis of these findings a new recommendation is made on the management of sheep grazing lupin stubbles. This recommendation requires regular and close examination of the sheep.
Production of two species and two interspecific hybrids of phalaris under irrigation in south-west New South Wales
Authors: Read JW , Lovett JV
Published: March 2005

Two phalaris hybrids (Siro 11 46 and allopolyploid) and the parent lines (Phalaris aquatica and P. arundinacea) were compared in monoculture with nitrogen fertilizer and in a mixed sward with white clover and lucerne. The experiment was flood irrigated and the effects of defoliating the swards at intervals of 21, 42 and 84 days were measured. The hybrid (Siro 11 46) was the most productive genotype at all defoliation intervals. Eighty one % of its annual yield occurred in spring and summer. This production imbalance renders Siro 11 46 unsuitable as the foundation of a pasture for high production throughout the year. The mixed sward produced more than the monoculture sward when defoliated every 21 or 42 days and there was increased production associated with increased defoliation interval. The monoculture sward was more productive than the mixed sward at an 84 day defoliation interval. The yield of Siro 1146 + white clover was 2.25 t ha-1 per 84 days, compared with a mean yield of phalaris + white clover of 1.78 t ha-1 per 84 days for the three other genotypes. The results indicate that Siro 11 46 grown with white clover and defoliated approximately every 42 days would be a suitable alternative pasture to Paspalum dilatatum and white clover in the two-pasture system used in irrigation areas of southern New South Wales. The problems of low acceptability and suspected toxicity of Siro 1146 are discussed.
An investigation of reduction in wheat yields after use of a high level of ammonium sulphate for a number of years
Authors: Mason MG
Published: March 2005

Investigations were carried out to determine reasons for reduced yields in two out of three multiple wheat cropping trials, where ammonium sulphate (S/A) was applied each year at 376 kg ha-1 (76 kg N ha-1). These included chemical analysis of soil and plant samples from the trials, and a pot trial on soil from the two affected sites at Merredin and Wongan Hills. At all three sites the SIAtreatment lowered soil pH and exchangeable bases and increased exchangeable H in the soil. Available Al was markedly increased at Merredin and Wongan Hills, the sites where yields were reduced, but to a much lesser degree on the third site at Beverley. Available Mn was increased at Beverley. The reductions in soil Mg and K were reflected in the contents of these nutrients in wheat tops from the sites, but Ca content was affected only at Merredin. Plant Mn levels were increased by S/A at Wongan Hills and Beverley, but Al levels did not show any consistent effects. The level of plant Mo was reduced by S/A at all sites. In pots, on soil from the high S/A plots at Merredin and Wongan Hills a large growth response to lime was obtained, but no growth responses to Ca, Mg or K. The response to lime was associated with a decrease in Al in the plants at both sites and an increase in P at Merredin. It was considered that Al toxicity was the most likely cause of the yield reductions, but that levels of K and Mo could also be marginal for healthy growth.
The effect of proportion of whole or rolled oats in steer rations on their digestibility
Authors: McDonald CA , Hamilton D
Published: March 2005

In a cross-over design, digestibility (D) of organic matter (OM), crude fibre (CF) and starch (S) was examined for steer rations containing hay plus 33 to 74% of whole or rolled oats at constant total DM. The DOM and DCF varied with proportion of grain in the ration, but did not differ with form of grain. The DS did not vary with proportion of grain, but was lower with whole than with rolled grain (93.8 cf 98.2%). The variation in the DOM was slight, with the highest value at about 60% grain. The DCF was highest at about 50% grain, and declined rapidly with a higher proportion of grain. The DOM of hay fed to reserve steers was 54.1%. By difference, the DOM of the oats at the lowest and highest proportion of grain was 78.1 and 67.0%, respectively. The results refute the hypothesis that proportion of grain in the diet may influence the relative digestibility, by beef cattle, of whole and rolled oats. However, they do suggest a detriment to animal performance if the ration exceeds an oats content of about 50-60%.
The comparative productivity of five ewe breeds. 2. Hogget wool production
Authors: Atkins KD
Published: March 2005

This paper contains information on the fleece characteristics of hogget ewes from five breeds in each of seven years at Temora Agricultural Research Station. Measurements of greasy fleece weight, clean scoured yield and the components of clean fleece weight were made on the following breeds: a Border Leicester x Merino fixed halfbred (BLM), Corriedale, Polwarth, a South Australian strong wool (S.A. Merino) and a medium wool Peppin strain of Merino. Average annual clean fleece weights were 3.53, 3.53, 3.04, 2.77 and 2.70 kg for the S.A. Merino, Corriedale, BLM, Peppin Merino and Polwarth breeds respectively. Average fibre diameters of these breeds were 23.1, 25.1, 27.2, 20.3 and 22.1 pm respectively. An interaction between breeds and years for clean fleece weight was associated with larger differences between the breeds in the years when environmental conditions favoured higher average clean fleece weights. Differences between breeds were large in all the components of clean fleece weight. Within breeds, the contribution of variation in follicle number to variation in clean wool weight was relatively greater in the Polwarth and Peppin Merino breeds than in the Corriedale and S.A. Merino breeds, with the BLM breed intermediate. The converse ranking applied to variation in fibre volume as a contributor to variation in clean wool weight within breeds.
A comparison of levels of production and profit from grazing Merino ewes and wethers at various stocking rates in northern Victoria
Authors: White DH , McConchie BJ , Curnow BC , Ternouth AH
Published: March 2005

Merino wethers and breeding ewes were grazed at various stocking rates on an annual pasture in the sheep-wheat zone of Northern Victoria from 1966 to 1973. There was considerable variation between years in botanical composition, the incidence of subterranean clover in the pasture plots varying by up to 80 percentage units between years. Total pasture production was measured in one plot during the last 4 years of the experiment, varying from 2.1 t ha-1 in the drought year (325 mm rain) of 1972, to 8.8 t ha-1 in the higher rainfall (883 mm) year of 1973. The large year-to-year variations in pasture production and botanical composition were reflected in differences between years in sheep production at various stocking rates. Wethers produced about 20% more wool than breeding ewes grazing at the same stocking rate, providing no supplements were fed. August-lambing ewes either lost weight in early spring or gained weight more slowly than wethers of the same age and flock background. The consequence of this was that maximum weights of ewes were consistently about 10 kg less than wethers at the same stocking rate. Both ewes and wethers had similar rates of weight loss from November to March. In one year ewes at 3.7 ha-1 were fed supplements in autumn, since they were lighter than the feeding weight of 41 kg, whereas wethers stocked at 11.1 ha-1, were not. An economic analysis of the experimental data indicated that the most profitable stocking rates of Merino wethers were up to 1.7 times that of August-lambing ewes. This ratio varies with season, and is also likely to vary with changes in lambing date or environment. The most sensitive determinants of optimal stocking rate were the rate of decline of fleece weight, and lambs born relative to ewes joined, with increasing stocking rate. Sheep liveweight at time of sale could also be important.
Phosphate sorption and extractable iron in soils during irrigated rice-upland crop rotations
Authors: Willett IR , Higgins ML
Published: March 2005

Two field experiments were conducted, in which phosphate sorptivity, acetate-(pH 4.8) and oxalate-(pH 3.0) extractable iron levels were monitored during irrigated rice-wheat-wheat and rice-fallow maize rotations in two clay soil types. Flooding for the rice crop markedly increased levels of phosphate sorptivity and extractable iron. On drainage of the rice crops, levels decreased rapidly but did not immediately return to levels occurring in the soils before flooding. Thereafter, levels of phosphate sorptivity and acetate-extractable iron slowly decreased during the following 21 months. Levels of oxalate-extractable iron in drained rice soils showed no consistent trends. The changes in phosphate sorptivity are described in terms of possible changes in the form of the iron hydrous oxides in the soil. The results indicated that the effectiveness of phosphate fertilizer to crops after rice should increase with time after drainage of the rice crop. More efficient use of phosphate fertilizer may be achieved by delaying the sowing of the following crop for as long as possible. There appeared to be little prospect for increasing the rate of decrease in phosphate sorptivity by management practices.
The effect of nitrogen fertilizer and irrigation frequency on a semi-dwarf wheat in south-east Australia. 1. Growth and yield
Authors: Cooper JL
Published: March 2005

An experiment in south-eastern Australia in 1971 examined the semi-dwarf wheat WW15 when grown with two rates of nitrogen fertilizer (nil, 112 kg N ha-1) and under four irrigation regimes. The irrigation regimes comprised natural rainfall only (293 mm), and 2, 3 or 7 flood irrigations, scheduled according to cumulative pan evaporation. Nitrogen fertilizer had little effect, but grain yield increased from 4.3 t ha-1 with no irrigation to 8.1 t ha-1 with 7 irrigations. Each increase in irrigation frequency produced a significant (P < 0.01) increase in grain yield. A greater individual grain weight contributed most to the yield difference between nil and 2 irrigations. More spikes m-2 contributed most to the yield increase with higher irrigation frequencies. Irrigations also increased plant height, dry matter, leaf area and the proportion of fertile shoots.