bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen fertilizer and wheat in a semi-arid environment. 4. Empirical yield response models and economic factors
Authors: Russell JS
Published: March 2005

The difficulties in predicting grain yield response to applied nitrogen under conditions of low and variable rainfall are discussed. Three models of grain yield response to applied nitrogen fertilizer for each of two strategies are proposed, based on data from field experiments carried out in the wheat growing areas of South Australia. In the first strategy (nitrogen applied at sowing) the parameters are May-August rainfall, October mean maximum temperature and one of three alternative site criteria, initial soil nitrate content (0-6 inches sampled shortly before sowing), 15-atmospheres soil moisture percentage (0-6 inches), or estimated nitrogen status. In the second strategy (nitrogen applied in late winter) the parameters are similar, except that May-July rainfall replaced May-August rainfall and a statistical relationship between yield response due to late application as compared with application at sowing was used. The response surfaces were examined using a calculated most profitable rate of application with a range of grain : fertilizer price ratios from 2 to 8. These calculations emphasize the importance of economic factors in affecting fertilizer use in areas where responses are small and variable. The limitations of the models and problems associated with the use of predicted climatic criteria are discussed. There is a need for further studies to iteratively test and modify these empirical models and ultimately to develop mechanistic models. Further study is also suggested on field aspects of late application and the possible role of both plant analysis and the single ion nitrate electrode for site characterization.
A constant level water system for long-term pot experiments
Authors: de Vries MPC
Published: March 2005

The performance of a constant level water system (CLWS) developed for long-term pot experiments was compared with watering at the surface. In an experiment with a soil with a good and stable structure, the CLWS was found to ensure a constant and adequate water supply even under very demanding conditions of plant growth, thus eliminating considerable fluctuations in soil water, risks of overwatering, and periods of water stress accompanying the technique of surface irrigation. When wheat was grown on five soils with different chemical and physical features, yields of dried tops were slightly lower with CLWS-watering. Between pot variation was significantly (P<0.001) lower with the CLWS than with irrigation at the surface. Seed emergence of French bean and root development of lucerne indicated that the structure of three out of five soils deteriorated during watering at the surface. Also, much of the surface gravel mulch sank into the soil during surface watering. By using the CLWS and porous cup tensiometers, it is possible to grow plants at soil water tensions below pF 2.8 and to determine more accurately than with irrigation at the surface when to terminate a pot experiment.
Contabescent anthers and poor boll development in cotton in the Ord River valley
Authors: Evenson JP
Published: March 2005

Widespread occurrence in cotton of 'parrot beaked' bolls, with one or more locule empty of seed, was shown to be related to periods when anthesis takes place under conditions of high temperature and water stress. Marked sowing date effects were recorded ; cotton sown in March and April having significantly lower percentage of parrot beaked bolls than cotton sown in December. Significant varietal differences in amount of the phenomenon were also recorded. The relationship between anther contabescence, and subsequent development of the parrot beaked condition, was clearly shown, and the effects of parrot beaked bolls on yield is discussed. Limited tests of lint quality showed no difference between lint from normal and parrot beaked bolls.
Chondrilla juncea in Australia. 2. Preplanting weed control and wheat production
Authors: Cuthbertson EG
Published: March 2005

The response of wheat to nitrogen fertilization and to the time and mode of skeleton weed control was determined at three locations in southern New South Wales. Nitrogen fertilization was found to increase grain yield significantly in most situations. But nitrogen reduced total grain yield where adverse seasonal conditions caused severe water stress after flowering. Added nitrogen exaggerated the water stress and reduced grain weight. Temporary removal of skeleton weed, obtained by spraying the fallow with 2,4-D four to six weeks before seeding, increased grain yield by an average of nearly 5 bushels an acre. The magnitude of the response was modified by rainfall incidence, weed cover, and time of spray application relative to seeding. The effects of chemical weed control, followed by crop competition, were apparent in stubble sown crops 12 to 18 months later in the form of reduced weed populations and increased grain yield. Preplanting sprays reduced the response to nitrogen fertilizer but the interaction, generally, was not significant. Spraying the fallow with a contact herbicide, or substituting an additional cultivation for the 2,4-D fallow spray, also increased grain yield. These results emphasize the importance of suppressing skeleton weed, by the most appropriate means available, in the period before sowing.
A nutritional evaluation of diets containing meat meal for growing pigs. 1. The effect of calcium level in wheat-animal protein diets
Authors: Batterham ES , Holder JM
Published: March 2005

Diets containing 1.4, 2.5, and 3.5 per cent calcium were fed to pigs in two experiments to observe the effect on performance of calcium level in diets containing animal protein supplements. Rate of liveweight gain and efficiency of food conversion were depressed as the level of calcium increased. There was also a trend towards a decrease in the lean content of the ham with increased calcium intake. Dry matter and organic matter digestibility of the diets were depressed as calcium intake increased, but no apparent effect on nitrogen retention was detected. There was no indication of parakeratosis in any of the animals.
The effect of delaying the introduction of concentrates on the summer milk production of hay-fed dairy cows
Authors: Radcliffe JC
Published: March 2005

From November 23, 1965, concentrates were introduced successively at two-week intervals to five treatment groups of grade Friesian cows that were being fed a basal ration of cereal hay in the paddock. The yield of milk, butterfat, solids-not-fat, and protein rose significantly as the supplements were introduced but almost no significant effect of concentrate feeding was observed on the weekly percentage composition tests of the milk. A comparison of the total covariance corrected yield results for the experimental period from November 23, 1965, to March 15, 1966, showed that the group of cows receiving concentrates throughout produced 30 per cent more milk, and 29 per cent more solids-not-fat, but only 24 per cent more protein and butterfat than the group receiving concentrates from January 18, 1966. However, the additional milk production would be uneconomic where milk is purchased on a butterfat basis.
Seasonal variation in the fertility and fecundity of Bungaree and Peppin Merinos in central-western New South Wales
Authors: Giles JR , Drinan JP
Published: March 2005

The seasonal variation in fertility and fecundity of Bungaree and Peppin Merinos was compared at the Agricultural Research Station, Trangie, New South Wales. Ewes of both strains were joined to rams of both strains for 32 days on nine occasions ; each joining being separated from adjacent periods by an interval of 10 days. For six weeks after joining the ewes were run with vasectomized rams and were then slaughtered over the following six weeks. Incidence of oestrus and ovulation rate of the two strains were similar at all times. More Bungaree than Peppin ewes returned to service, particularly during the autumn, irrespective of the strain of rams to which they were joined. There was no difference between ram strains in percentage of ewes returning to service or percentage of ewes pregnant, but a significantly higher proportion of ova were lost in pregnant ewes with multiple ovulations after joining to Bungaree rams in winter and spring.
Birth weight and survival of Merino, Corriedale, and Polwarth lambs
Authors: Mullaney PD
Published: March 2005

The effects of year of birth, age of dam, sex, and litter size upon birth weight of lambs were examined by least squares analysis in eight flocks in Western Victoria (4 Merino, 3 Corriedale, and 1 Polwarth). Male lambs were approximately 0.8 lb heavier (P<0.01) than female lambs, single lambs about 1.6 lb heavier (P<0.01) than twin lambs. Lambs, born of 5-year-old ewes, were generally heavier (P<0.01) at birth than lambs from ewes of other ages. A general set of adjustments of birth weight for these sources of variation are presented for each breed. The effects of the same sources of variation on survival of lambs to weaning were calculated by least squares analysis. Regressions of survival on birth weight (BW), BW2 and BW3 were included in the analysis. Male lambs did not survive as well as female lambs and a higher proportion of twin lambs died than single lambs. Lambs from primiparous ewes generally did not survive as well as those from multiparous ewes. Maximum survival occurred at birth weights of about 10 lb (Merino), 11 lb (Corriedale), 8 lb (Polwarth).
The growth and development of Townsville lucerne (Stylosanthes humilis) in ungrazed swards at Katherine, N.T
Authors: Fisher MJ
Published: March 2005

At Katherine, N.T., swards of Townsville lucerne (Stylosanthes humilis H.B.K.) were sown in late November and late December, 1964, and sampled every two weeks during the growing season. At each harvest the dry matter, nitrogen, and phosphorus yields of stem, leaf and petiole, inflorescence, unshed pods, shed leaf, and shed pods were determined. Crop growth rates and net assimilation rates (leaf weight basis, ELW), were derived for both plantings and compared with calculated soil water storage. Drought in January and February restricted growth during the vegetative phase, but rapid growth resumed when water stress was relieved by rain in March. Maximum dry matter yield (5400 lb an acre) and mean crop growth rate (42.3 lb an acre a day) for the November sowing were similar to those measured for Townsville lucerne at Katherine and elsewhere. Maximum crop growth rates (250 and 110 lb an acre a day for the November and December sowings respectively) appear to be about the same as those recorded in the field for subterranean clover. The strong influence of water stress on growth was emphasized by the close relationship demonstrated between ELW and calculated soil water storage. Uptake of nitrogen and phosphorus was restricted during water stress and both were redistributed to reproductive parts of the plant during flowering and seeding, nitrogen more readily than phosphorus. Nitrogen and phosphorus contents (1.9-2.0 per cent N and 0.70-0.75 per cent P) were lower than those recorded for other tropical and temperate pasture legumes. The implications of the low phosphorus contents of Townsville lucerne as cattle feed are discussed.
A hand-operated seeding device for experimental field sowing of inoculated legume seeds
Authors: Ireland JA
Published: March 2005

The problem of spacing inoculated legume seed in field-situated Rhizobium strain trials, without risk of cross-contamination, is discussed. A portable and versatile hand operated machine, capable of delivering individual inoculated legume seeds to the drill row without cross-contamination is described. Detail sufficient to permit construction by a competent tradesman is provided. Spherical seeds ranging in size from white clover (Trifolium repens) to golden tares (Vicia sativa) and irregularly shaped seeds such as lucerne (Medicago sativa) and barrel medic (Medicago truncatula) have been successfully sown.
The distribution and host-plants of the species of Quadraspidiotus (Homoptera : Diaspididae) in Australia
Authors: Brookes HM , Hudson NM
Published: March 2005

Inspections made in the pome fruit orchards of Australia during 1961-66 showed that four species of Quadraspidiotus, viz. Q. perniciosus (Comst.), Q. ostreaeformis (Curt.), Q. pyri (Licht.), and Q. lenticularis (Lind.) occurred on pome fruits and other deciduous plants. Quadraspidzofu.r perniciosus, which is a pest in most of the orchard districts of Queensland, New South Wales, Victoria, South Australia, and Western Australia, also occurs in Tasmania, while Q. ostreaeformis occurs in southern Tasmania, Victoria, and South Australia. The other two species (Q. lenticularis and ,Q. pyri) are at present confined to South Australia and Tasmania respectively. The most widely distributed species, Q. perniciosus osw, is also, economically, the mcst important because its presence on fruit may cause it to be rejected by quarantine authorities at certain ports of entry overseas. Though Q. ostreaeformis and Q. pyri are regarded as minor pests in orchards, Q. lenticularis is at present of no economic significance.
Responses of peach seedlings in sand culture to factorial combinations of nitrogen, phosphorus, and sheep manure
Authors: van den Ende B , Talor BK
Published: March 2005

A factorial experiment was done on Elberta peach seedlings growing in sand culture to test tree response to applied solutions of calcium nitrate and sodium dihydrogen phosphate, and to sheep manure which had been mixed throughout the sand before planting. Results showed that the phosphate and sheep manure treatments exerted a more pronounced influence on seedling growth and leaf nutrient composition when harvested after 9 weeks than did the nitrogen treatments. In the absence of sheep manure, seedling growth was increased by increasing the phosphate supply to the maximum tested (64 p.p.m. P). A strong, negative interaction was found between phosphate and sheep manure treatments in both seedling growth and leaf composition data, and it is concluded that the sheep manure served as a rich source of phosphate in this situation. In addition, application of sheep manure (except in the presence of 64 p.p.m. P) apparently increased uptake of N, P, K, Ca, and Mg by the seedlings, and also increased the concentrations of Ca, K, and P in the leaves. Other results relating to leaf composition are discussed and it is suggested that a Ca/Mg antagonism was operative.
The effect of burning and seasonal rainfall on native pasture at Katherine, N.T
Authors: Norman MJT
Published: March 2005

An 11-year experiment at Katherine, N.T., on the effects of time and frequency of burning on the yield and composition of native pasture on Tippera clay loam is described. In comparison with plots burned biennially in January, April, or September, the annual dry matter and nitrogen production of control plots after 5-10 years of protection from fire was low. On the other hand, production in the first five years after burning of plots that had been protected for five years and then burned was high. Under conditions favouring the accumulation of dead material, a burn every five years or so appears to be more favourable than annual or biennial burning or no burning at all. The contribution of Themeda australis and Chrysopogon fallax to total dry matter yield was negatively related to total rainfall in the two preceding seasons, and that of Sorghum plumosum positively related.
Assessment of the phosphorus and sulphur status of subterranean clover pastures. 2. Soil tests
Authors: Spencer K , Bouma D , Moye DV
Published: March 2005

Values obtained by a number of established soil test procedures for phosphorus and sulphur were correlated with yield responses to addition of the relevant nutrient, by subterranean clover-based pastures at 21 sites in south-eastern New South Wales. Colwell's bicarbonate-soluble P and Bray's P, phosphorus values showed sufficiently close associations with response to added phosphorus to be useful for predictive purposes ; Bray's P, values generally gave smaller coefficients. In general, the pasture on soils testing less than 25 p.p.m. bicarbonate-extractable P in the surface three inches responded appreciably to applied phosphorus (relative yields were <85 per cent). The corresponding value for the Bray P, procedure was 10 p.p.m. P. Soil samples from 0-1, 0-3, and 3-6 inch depths gave similar correlations with response. The time of soil sampling did not affect the relationships but winter pasture production was not as closely related to soil test values as was spring production. By contrast, soil tests for sulphur were not reliable but some discrimination between soils could be made with a 500 p.p.m. phosphate extraction. Values from soil samples collected in the winter were less closely related to response than were values from samples collected in the autumn.
Assessment of the phosphorus and sulphur status of subterranean clover pastures. 3. Plant tests
Authors: Bouma D , Spencer K , Dowling EJ
Published: March 2005

Field experiments were carried out in south-eastern New South Wales to establish the relationships between three plant tests for phosphorus and for sulphur, and the yield responses of subterranean clover pastures to applied phosphorus and sulphur. Subterranean clover plants (CV. Mt. Barker), sampled early in the growing season of 1963 and on five occasions at approximately monthly intervals in 1964, were analysed for total and soluble phosphorus and for total and reducible sulphur. The third plant test involved a comparison of the leaf area responses measured seven days after transfer to appropriate nutrient solutions of clover plants sampled in the field plots at the beginning of each growing season. Correlation coefficients (R) varying from 0.546 to 0.908 were obtained for the curvilinear regression of relative yields on total phosphorus contents of the clover, but only under conditions of an adequate sulphur supply. The correlation coefficients for soluble phosphorus were generally lower and differed greatly between samplings. The correlation coefficients for the curvilinear regressions of yield responses on the total or reducible sulphur content of clover, under conditions of ample phosphorus supply, were never less than 0.606 at the end of the season, and for some of the earlier samplings were as high as 0.947. The correlation coefficients (r) between leaf area responses and yield responses to phosphorus were 0.576 and 0.716, and those for sulphur 0.710 and 0.692 in 1963 and 1964 respectively. In contrast to those based on leaf analysis, the relationships between leaf area responses and yield response for each one of the elements were not affected by the level of supply of the other element.
MPA impregnated intravaginal sponges for the induction of oestrus in anoestrous Border Leicester × Merino ewes. 1. Lactating ewes
Authors: Dawe ST , Roberts EM , Killeen ID
Published: March 2005

In the spring of 1965, anoestrous lactating Border Leicester X Merino ewes were treated for 13 days with intravaginal sponges impregnated with 17a - acetoxy 6a - methylpregn - 4 - ene - 3,20 - dione (MAP) 7-11 weeks after lambing. Each ewe received 1000 i.u. Pregnant Mare Serum Gonadotrophin (PMSG) at the time of sponge removal. Half of the ewes received another 1000 i.u. PMSG 16 days after sponge removal. In the 2-4 days after sponge removal 80.5 per cent of the treated ewes exhibited oestrus, and 75.8 per cent of these were pregnant at autopsy 15 weeks later. The mean number of foetuses per pregnant ewe was 2.46. It was not until approximately 15 weeks after the period of treatment that a similar number of untreated ewes had exhibited oestrus. The second injection of PMSG had no effect on either the number of ewes pregnant or on the number of foetuses present at autopsy. This was largely due to the high rate of conception at the first induced oestrus.
The partial replacement of soybean meal by amino acids in pig rations based on wheat and sorghum
Authors: Beames RM , Pepper PM
Published: March 2005

In five experiments involving 104 pigs, rations consisting of grain and 15 per cent soyhean meal as the major components were compared with rations of grain plus 7.5 per cent soybean meal in combination with lysine and methionine. In three of the experiments, comparisons were also made between wheat and sorghum as basal grains. The results showed a response in growth rate and feed efficiency to the addition of 0.24 per cent L-lysine HCl.2H2O either with or without 0.20 per cent DL-methionine to rations of grain plus 7.5 per cent soybean meal. From weaning to 45 kg body weight the growth rates of pigs fed these amino acidsupplemented rations were consistently less than those obtained with pigs fed the grain plus 15 per cent soybean meal rations, although not always significantly so. From 45 kg to the final slaughter weight of approximately 90 kg, only in one experiment were the results obtained with the rations containing 7.5 per cent soybean meal plus amino acids significantly less than those obtained with the 15 per cent soybean meal rations. Where comparisons were made between wheat and sorghum, the wheat-based rations consistently produced better growth rates and feed efficiencies, and in one experiment better carcase measurements.
Cottonseed meal as a source of protein in diets for laying hens
Authors: Saville DG , Smith L , Nicholls P
Published: March 2005

Diets containing graded levels of cottonseed meal (0, 5, 10, and 15 per cent) have been compared when fed to laying pullets for seven months. The influence of ferrous sulphate and lysine supplements was also investigated. As the proportion of cottonseed meal in the diet increased, production of eggs, egg weight, and specific gravity decreased, while feed consumption per dozen eggs and Haugh Index increased. Cottonseed 413 meal treatments resulted in darker egg yolks and depressed hatchability. Neither lysine nor ferrous sulphate influenced egg production, but ferrous sulphate significantly reduced the incidence of dark yolks and increased the mean hatchability. Analysis of cottonseed meal indicated that the gossypol content of the diets was less than the minimum previously reported to have a detrimental effect on egg production. It was concluded that cottonseed meal could not be used as a major protein supplement in layer diets.
The effect of feed restriction on sexual maturity and initial reproductive performance of broiler pullets under different light treatments
Authors: Pym RAE , Sledge R
Published: March 2005

An experiment was conducted to examine the effect of restricted feeding under two lighting systems during the rearing period on the initial laying performance of broiler type pullets. The rearing treatments were imposed at nine weeks of age, removed at 22 weeks and the trial was discontinued at 36 weeks of age. The feeding treatments (restricted versus ad lib.) were arranged factorially with the lighting treatments (decreasing versus increasing). Birds reared on restricted feeding reached sexual maturity 16 days later than full fed birds, ate 17 per cent less feed to 22 weeks and gained seven per cent less in body weight to 24 weeks of age and ten per cent less to 36 weeks. Birds reared under the decreasing lighting regime reached sexual maturity at the same age as those reared under increasing lighting, ate five per cent more feed during the rearing and laying periods and gained five per cent more in body weight to 24 weeks. The mean weight of eggs laid between 24 and 34 weeks of age from pullets subjected concurrently to decreasing lighting and restricted feeding was approximately two grams heavier than that of the other three treatment combinations. Mean egg weight was one gram greater in the restricted than in the full fed group, although the difference was not statistically significant. Laying mortality was lower in the restricted fed group than in the full fed group.
The effect of sodium molybdate mixed in the lime seed pellet on nodulation, nitrogen content, and growth of subterranean clover
Authors: Gartrell JW
Published: March 2005

Sodium molybdate at l 1/2 oz, 3 oz, and 6 oz mixed with 6 lb ground limestone and pelleted onto 12 lb of Trifolium subterraneum cv. Geraldton inoculated with peat culture markedly reduced clover nodulation, growth, and combined nitrogen production compared with nil sodium molybdate. Mixtures of sodium molybdate l 1/2 oz, 3 oz, and 6 oz with l80 lb superphosphate drilled at 180 lb an acre with 12 lb an acre clover seed inoculated and pelleted with 6 lb ground limestone had no effect on nodulation, increased dry matter production by 70 per cent, and increased nitrogen per acre in tops by 110 per cent compared with nil sodium molybdate. The differences persisted into the second growing season.
Root mapping of three tropical pasture species using 32P
Authors: Bray RA , Hacker JB , Byth DE
Published: March 2005

Root growth patterns of Glycine javanica, Setaria anceps, and Medicago sativa were studied by uptake of 32P from a sandy loam. Placement of isotope was through permanently positioned PVC conduit on a grid over a 90� quadrant of the root system. Detection of radioactivity was in in situ plant material. Lucerne had strong initial root development but was slow to form lateral roots. Glycine and Setaria had quite similar root systems although Setaria had more rapid vertical root development than Glycine. Both these species had strong lateral root systems. When a regression of minimum root length against time was calculated, lateral root growth was shown to be independent of depth and distance from the plant, suggesting that roots behave as if growing from a point source in random directions at a constant rate. This rate was the same for all species. There were also indications of strong vertical root systems in lucerne and Setaria.
Calibration equations for submerged segmental orifice flowmeters
Authors: Bridge BJ , Daws GT
Published: March 2005

Regression equations for the calibration curves of submerged segmental orifice flow-meters suitable for use in flood irrigation experiments are given. hfeter diameters ranged from l 1/4 inches to 6 inches and all had a throat width to diameter ratio of 0.64. The calibration equations were of the general type Q = aH0.5,, where Q is the flow rate in cusecs, H is the head loss across the meter in inches and a is a coefficient dependent on the area of the orifice. The relationship between coefficient a and orifice area A in square inches was linear, the regression equation being a = 0.0040 + 0.0113A. The regression equation between coefficient a and meter diameter D in inches was a = 0.00704D1.92 The two relationships enable the calibration curve for any meter between l$ and G inches diameter and with a throat width to diameter ratio of 0.64 to be predicted with a maximum error of per cent. Experience with the meters in the field has shown that the flow-meters need to be constructed out of materials with smooth surfaces. Rigid PVC plastic piping has this characteristic and the added advantages of being light, easily handled, and corrosion resistant. Details of installation in the field are also given.
The occurrence of biotypes of the cereal cyst nematode (Heterodera avenae Woll.) in Victoria
Authors: Brown RH
Published: March 2005

Ten cereal cyst nematode (Heterodera avenae Woll.) populations from the Victorian Mallee and Wimmera districts, were tested for their variation in pathogenicity, using a selected range of indicator varieties. Of the oats used, Avena sterilis and A. strigosa were resistant to all populations, while A. abyssinica and CV. Sun II were both susceptible. None of the cultivars of barley or wheat was resistant ; the spring wheat CV. Loros was very susceptible. Rye CV. South Australian was resistant to all populations. The results presented indicate that only one biotype of H. avenae is present in Victoria, and that it is unlike any of those known to occur in Europe.
Interaction of spore concentration and fungicide concentration on the control of pineapple disease of sugar cane setts
Authors: Patil-Kulkarni BC , Aberdeen JEC
Published: March 2005

Sugar cane setts were artificially inoculated with spores of Ceratoytis paradoxa (pineapple disease), treated with a range of concentrations of mercuric fungicides and planted out in the field, near Brisbane, Queensland. At a constant concentration of inoculum, infection (as judged by shoot emergence, eye sprouting, and macroscopic signs of infection) decreased as the concentration of the fungicide increased. When the concentration of spores in the inoculum was increased the fungicide concentration needed to be increased to maintain a given level of control. Of the two fungicides tested, BSM11 (10 per cent phenyl mercuric acetate and 50 per cent potassium 2,4,6 trichlorophenate) was slightly more effective than Aretan (6 per cent w/w organically combined mercury). The possibility of phytotoxicity of the mercury fungicide was shown. The complicating effect of infection by other organisms is discussed.
Field evaluation of a new fungicide (bedomyl) for apple scab
Authors: Moller WJ , Wicks TJ , Steed JN
Published: March 2005

Benlate (R), (benomyl) a new experimental fungicide, was tested against app1.e scab (Ventaria inaequalis (Cke.) Wint.) in South Australia in the 1968-69 season. In an orchard heavily infected with scab it gave equal or better control OF the disease than did Melprex (R). Benlate (50 per cent wettable powder) was used at rates of 4 oz and 2 oz to 100 gallons every 14 days, and 4 oz to 100 gallons every month ; Melprex (65 per cent wettable powder) was used at 8 oz to 100 gallons every 14 days. Both materials were applied as protectants only.
Effect of age at first joining on lifetime production by Border Leicester × Merino ewes
Authors: Cannon DJ , Bath JC
Published: March 2005

Three hundred and fifty Border Leicester X Merino ewes, born March-April 1961, were drafted to two flocks, A and B. Flock A only was joined with rams on February 14, 1962. Subsequently both flocks were joined in November or December each year from 1962 to 1965. The flocks were depastured together on all occasions except for joining and lambing of flock A in 1962. There were negligible differences, between the flocks, in ewe deaths, wool cut, lambs born and reared, lamb birth weight and lamb carcase weight for the mean for the four years or in each of the years 1963 to 1966. Meat production in flock A was increased by 12 kg per ewe as a result of the extra lambing. On the other hand, 3 per cent of the ewes of flock A died in 1962 but no deaths occurred in flock B. Joining when 10-11 months old in early autumn did not disrupt the practice of joining when 20-21 months old in early summer, and, in the experiment, was the most profitable procedure.
A comparison between barley and sorghum when combined with soybean meal or meat and bone meal in rations for growing pigs
Authors: Beames RM , Sewell JO
Published: March 2005

Two experiments are reported. In the first experiment, 48 Large White pigs were individually fed from 22.2 to 86.5 kg bodyweight, with rations containing either sorghum or barley in combination with 16.6, 13.8, 10.7, or 7.4 per cent soybean meal. Type of grain did not affect growth rate or feed efficiency but carcase measurements indicated that the barley-fed pigs were leaner. There were no significant differences in growth rate or feed efficiency between the 16.6 per cent and 13.8 per cent soybean meal rations before 45 kg bodyweight or between the 16.6 per cent, 13.8 per cent, or 10.7 per cent soybean meal rations after 45 kg bodyweight, but all rations containing the three higher levels of soybean meal gave significantly better growth rate and feed efficiency than the rations containing 7.4 per cent soybean meal for both bodyweight ranges. Final results showed no significant differences between the 16.6 per cent and the 13.8 per cent soybean meal rations in growth rate, feed efficiency, or carcase measurements of pigs receiving these rations, but growth data and carcase measurements were poorer with the two lower levels of soybean meal supplementation. In the second experiment, 40 Berkshire pigs were individually fed barley or sorghum grain with 15 per cent soybean meal or 20 per cent of one of three meat and bone meals. Pigs were fed from 25.8 to 74.0 kg bodyweight. The sorghum-based rations gave significantly better growth rates and feed efficiencics than the barley-based rations after 45 kg bodyweight, but carcase appraisal indicated greater lean content in the barley-fed pigs. Growth rates and feed efficiencies obtained with rations containing two of the meat and bone meals were significantly (P<0.05) less than values obtained with the rations containing soybean meal. Pigs fed the third meat and bone meal grew only slightly more slowly than those fed soybean meal. Type of supplement had no effect on carcase measurements.
Resistance of some Australian inbred maize lines to maize dwarf mosaic disease
Authors: Grogan PW , Teakle DS
Published: March 2005

Seven out of eight maize inbred lines developed at Lawes in Queensland from open-pollinated varieties were resistant to maize dwarf mosaic disease when exposed to natural infection in the field. Five of the seven resistant inbred lines failed to become systemically infected when inoculated with infectious sap in the glasshouse. By contrast, only three out of twenty lines introduced from the U.S.A., and two out of eight lines developed at the Grafton and Glen Innes Breeding Stations in New South Wales, were resistant in the field. All three resistant lines from the U.S.A. were systemically infected when inoculated in the glasshouse, but the two resistant lines from Grafton in New South Wales were not. The resistant Lawes and Grafton maize inbred lines would appear to be better sources of genes conferring resistance to maize dwarf mosaic disease than the other lines tested.
Different levels of resistance in blue mould resistant tobacco
Authors: Wuttke HH
Published: March 2005

Seedlings of resistant tobacco lines were assessed for leaf reaction to blue mould infection at normal transplanting size and grouped in four levels of reaction. Segregation ratios from heterozygous plants confirmed the presence of a single major gene for resistance and suggested the presence of additional minor genes. Selection based on seedling reaction has accumulated minor genes for resistance in the presence of the major gene and has resulted in a very high level of resistance to the strain APT1 in both seed bed and field. The relation between the resistance levels was similar in the parent and two subsequent selfing generations. The relative disease expression at the different levels of resistance in seedlings and field plants was positively correlated.
The partial and total replacement of wheat and soybean meal by pollard in a wheat-soybean meal grower-pig ration
Authors: Beames RM , Natoli WJ
Published: March 2005

This experiment was designed to investigate the effect of high levels of pollard in the ration on the growth and carcase quality of growing pigs. Twenty-four gilts and twenty-four male castrate weaner pigs of mean liveweight 23.4 kg were each fed one of four rations in a wet form in individual stalls twice daily until they were slaughtered at a mean liveweight of 86.5 kg. The control ration was 81.9 per cent wheat and 15.0 per cent soybean meal, with added minerals and vitamins. In the other three rations, the wheat and soybean meal portion was replaced by 48.4, 67.8, and 96.9 per cent pollard. Feed allowance was adjusted to give a similar intake of digestible energy for all rations. There was no significant difference between treatments in rate of liveweight gain or in efficiency of utilization of digestible energy. Efficiency of utilization of air-dry feed decreased as level of pollard in the ration increased. These differences were significant except for the difference between the rations containing 48.4 and 67.8 per cent pollard. There was a significant decrease in dressing percentage with each increase in the level of pollard in the ration. Backfat thickness was significantly less in pigs fed rations containing 67.8 and 96.9 per cent pollard than in pigs fed the other two rations. Gilts grew more rapidly, utilized feed and digestible energy more efficiently and produced carcases with greater eye muscle indices and higher appraisal scores than the male castrates. There were no digestive disturbances on any of the rations and all were readily eaten. The results indicate that the relationship between protein quality k d net energy in pollard is of an order normally occurring in well-balanced rations.
The chemical composition, digestibility and intake of some native pasture species in central Australia during winter
Authors: Newman DMR
Published: March 2005

The chemical composition, digestibility, and voluntary intake of four perennial grasses, three annual grasses, two shrubs, and five forbs cut during winter in central Australia, were determined in pen feeding trials with sheep. There was no significant difference in digestible organic matter intake between the group of grasses and the shrubs and forbs. It is unlikely, however, that these grass-forb pastures become protein deficient during dry periods.
The effect of nitrogen fertilizer on the seasonal production of irriagted perennial grasses in coastal New South Wales
Authors: Wolfe EC , Crofts FC
Published: March 2005

The seasonal productivity of eight perennial grasses at three nitrogen levels was measured in small pure-grass swards at Badgery's Creek, New South Wales. Highly significant differences in seasonal productivity were found between nitrogen levels in all four seasons, and between cultivars in summer, autumn, and winter. The response of the grasses to nitrogen was slightly greater at the high than at the medium level of nitrogen application in all seasons, and was highest in spring (about 40 lb of dry matter per lb of applied nitrogen) and lowest in mid-winter (about 8 lb/lb). Tall fescue was the most efficient responder to nitrogen in late summer and early autumn, Kangaroo Valley ryegrass in late autumn and late winter, and Currie cocksfoot in mid-winter. At a high level of nitrogen, the dry matter produced by Kangaroo Valley ryegrass and Currie cocksfoot in the late autumn to early spring period, the period of greatest feed shortage, was nearly as great as that produced over a similar period by sod-sown oats in earlier experiments at Badgery's Creek.
Responses by pasture to current and previous application of superphosphate
Authors: Cameron IH , McGowan AA
Published: March 2005

The effects of heavy initial applications and regular annual dressings of superphosphate on the winter and spring yields of herbage from a subterranean clover-annual grass pasture were measured in a four-year experiment at Rutherglen, north-eastern Victoria, Basal levels of soil phosphorus were established in 1959 by applying 1, 7, or 13 cwt (112 lb) of superphosphate an acre to an established pasture. From 1960-1963, 0 or 1 cwt of superphosphate an acre a year was applied in all factorial combinations (i.e., 0-0-0-0, 0-0-0-1, . . . . . . . . 1-1-1-1). On the plots that received 1 cwt an acre in 1959, current application of superphosphate increased winter production in every year (by 425-1230 lb dry matter an acre, or 36-362 per cent). On the plots that received 7 or 13 cwt an acre in 1959, winter responses to current dressings were small and not significant in three of the four years, indicating a strong residual effect from the basal dressings. Responses in spring were small in both absolute (maximum 290 lb dry matter an acre) and relative (4-12 per cent) terms and were not significant in three of the four years. Tn both winter and spring yields, residual effects of current dressings were small (maximum 245 lb dry matter an acre) and generally not significant.
The influence of transplanting on the growth of the tobacco crop
Authors: Hopkinson JM
Published: March 2005

In two field experiments at Mareeba, Queensland, the effects on the subsequent development of tobacco plants of the degree of root damage received at transplanting, and of the stage of development of the transplant, were investigated. Early leaf expansion was slightly delayed by severe root damage, and slightly advanced when damage was reduced. No lasting effects of either treatment were observed, however. Total elimination of root damage by use of pot-raised seedlings shortened the period between transplanting and flowering, and reduced the numbers of leaves initiated. The greater increase in area of the lower leaves compensated for the smaller leaf number, with the result that neither the yield of cured leaf nor the total leaf area of pot-raised plants differed appreciably from that of seedbed-raised plants. The treatment did, however, have an adverse effect on leaf quality. The more advanced the development of the seedling at transplanting, the greater was the number of lower leaves stunted by the associated stresses ; but the deficiency was always balanced by the increased expansion of the upper leaves. There were no consistent yield differences that could be attributed to these effects. The remarkable compensatory ability of tobacco is emphasized and discussed in relation to seedling treatment and climate.
Sampling for weight changes in animal populations with or without identification
Authors: Verhagen AMW
Published: March 2005

Procedures for studying weight changes in animal populations by sampling on successive occasions, may or may not involve identification of the animals sampled. Since changes in a population are in general more precisely estimable from animals common to both samples, identification of the common animals enables a change in the mean weight of the population to be estimated more precisely, since then the submeans of the common animals become available for utilization in the construction of the estimators. The extent to which animals are identified during the two weighings determines whether two, one, or none of these submeans are ascertainable from the data. Accordingly there are three different procedures for estimating a change in the population's mean weight with minimized variance, one appropriate for each case. To enable comparison, the variances of these three estimators are tabulated as a function of the number of animals common to both samples and the correlation between successive weight measurements. The effect of various weighing practices in farming and research on the precision of the best obtainable estimators of change are discussed. The general formulas developed for the variance in each case pinpoint the components of variation and enable calculation of the precision to be gained by manipulating these.
The sodium concentration in some tropical pasture species with reference to animal requirements
Authors: Playne MJ
Published: March 2005

A survey was made of the sodium concentration in eight grass and legume pasture species in the Townsville region. The grass species could be characterized according to sodium concentration. Panicum maximum, Chloris gayana, and Cenchrus setigerus were 'high-sodium' species (>0.40 per cent Na), whereas Urochloa mosambicensis had a medium sodium concentration, and Cenchrus ciliaris, Heteropogon contortus, and the legumes Stylosanthes humilis and Phaseolus atropurpureus were `low-medium� species (<0.10 per cent Na). The sodium concentration in five species grown at five sites located within 257 kilometres of Townsville, Queensland, was also examined at one stage of growth. Since several common pasture species contained low levels of sodium (<0.05 per cent of dry matter) deficiency symptoms could occur in grazing stock under certain circumstances.
Growth and ignitability of annual pastures in a Mediterranean environment. 1. Effect of length of season and of defoliation on the growth, water content and desiccation of annual pastures
Authors: Parrott RT , Donald CM
Published: March 2005

The growth and water content of annual swards were examined in a Mediterranean environment under three lengths of season (attained by extension of the natural season by irrigation), and under two defoliation treatments. Swards attained their maximum percentage water (about 800-950 per cent of the dry matter) in late July or early August. Maximum dry matter yields were attained two months later, when the percentage water had fallen to 150-400 per cent. The swards were dead and dry about 50 days after maximum yield. Earlier commencement of the growing season (18 days) doubled the winter production, delayed desiccation, in the spring and gave heavier dry herbage in the following summer. Extension of the season in the spring gave little response by undefoliated swards, but a considerable response by defoliated swards ; it failed to prevent the maturation and desiccation of these annual pasture plants. Autumn irrigation gave a greater return of dry matter per inch of water than did spring irrigation. The influence of these practices on pasture growth and summer fuel production is discussed.
The effect of varieties, nitrogen and stubble treatments on successive cycles of grain and forage sorghums in the Ord River valley
Authors: Mackenzie DH , Basinski JJ , Parbery DB
Published: March 2005

Two exploratory experiments with re-cycled (ratooned) grain sorghums (hybrid Texas R.S. 610 and standard variety Alpha) and forage sorghums (hybrid Sudax and standard variety Sugardrip) were carried out at Kimberley Research Station to provide data for the initial assessment of sorghum production possibilities in the Ord River area. Re-cycling of sorghum led to progressive reduction in grain and dry matter yields. Grain yield reduction was greater when stubble was cut at the header height (approximately 40 inches) than when it was cut at 6 to 8 inches above ground level and removed. Grain and dry matter yields were higher for Texas R.S. 610 than for Alpha, while dry matter yield of Sudax was also higher than that of Sugardrip. Nitrogen application at 50 lb N an acre and 100 lb N an acre increased grain yields of Texas R.S. 610 and Alpha. It also increased dry matter yields of these two varieties and of Sugardrip, while dry matter yield of Sudax did not respond above the 50 lb N an acre rate of application. Relative, but not absolute, reduction of grain and dry matter yields in successive cycles was diminished by nitrogen application.
The effect of manganese on tobacco leaf quality and on the inorganic cation levels of tobacco
Authors: Johnson AD , Knowlton RW
Published: March 2005

In a series of field and pot experiments, quality of cured leaf of tobacco plants Nicotiana tabacum, was adversely affected by increasing leaf levels of manganese. The quality decline manifested itself as a leaf 'greying' effect. Leaf manganese concentrations were readily increased by either foliar or substrate application of manganese. The increase in leaf manganese content was associated with a significant increase in potassium concentration and a significant decrease in calcium concentration in leaves. Sodium and magnesium leaf concentrations were not greatly affected by manganese. It is suggested that the decline in cured leaf quality was associated primarily with a change in the K : Ca : Mg ratio, which occurred at relatively low concentrations of manganese in the leaves. The results of this investigation indicate that the use of manganese-based fungicide sprays could cause a further quality decline of tobacco produced on soils containing high levels of exchangeable manganese.
Packaging treatments for the storage and export of Austrtalian grapes
Authors: Beattie BB , Outhred NL
Published: March 2005

Comparisons of packing materials for table grapes were carried out during 1966, 1967, and 1968 to find a suitable alternative to granulated cork, the present export pack for grapes. Packs of Purple Cornichon, Gordo Blanco, and Waltham Cross grapes were examined for acceptability after long storage; and to confirm their suitability for export. A pack of tissue-wrapped grapes in wood-wool interspersed with tablets of sodium metabisulphite was the most promising. Grapes stored in this pack were considered acceptable after periods greater than those normally encountered during export.