bluuebunny/crossref_metadata_2025 huggingface dataset:
Pre-maturation cold acquisition in Trifolium subterraneum
Authors: Collins WJ , Smith DF
Published: November 2004

The influence of different levels of temperature during seed maturation on the subsequent rate of development in plants grown from that seed was studied in a range of subterranean clover cultivars. In one study the cultivars Carnamah, Yarloop, Woogenellup and Mt. Barker were grown at 7, 11, 14 and 17°C, and the seed produced grown on at 17°. Observations were made on the rate of leaf appearance, time of flower initiation, and time and node of first flowering. The rate of development was closely related to the temperature under which the seed was produced—the lower the temperature the faster was the rate of development. This effect was greatest with the later-flowering cultivars. In a second experiment, seed of a number of cultivars harvested commercially from a wide range of sites in southern Australia was grown on at 17°C and the rate of development observed. Time of flowering varied markedly between samples of only three cultivars. Accordingly seed of these samples were grown on for a further generation in a controlled environment. Within two of the cultivars, Mt. Barker and Bacchus Marsh, the differences in flowering observed in the previous generation persisted, which suggests that such differences were not based on environmental factors. In the cultivar Woogenellup the differences in flowering disappeared, which suggests that the original differences arose through different environmental conditions occurring during seed maturation. Cold acquisition in the maturing embryo does not seem to be a matter of practical consequence at present in subterranean clover, but may become so with changes in the location of seed production.
The influence of abomasal supplements of methionine on wool growth of wheat-fed sheep
Authors: Reis PJ , Tunks DA
Published: November 2004

Sheep receiving a diet consisting solely of wheat (500 g/day), supplemented with a mineral mixture, were given abomasal infusions of varying amounts of DL-methionine (1.5–6.0 g/day) or of L-cystine (5 g/day). Other sheep received DL-methionine as a supplement to a roughage diet. All levels of methionine infused caused a decrease in the mass of wool grown by sheep consuming the wheat diet. This effect was greatest with 6 g methionine and was due mainly to a considerable depression of fibre diameter. Smaller amounts of methionine decreased fibre diameter and increased length growth rate. The infusion of methionine caused a considerable weakening of the wool grown by most of the sheep, with the result that a 'break' was observed in the fleece after about 1 week of methionine administration. This effect occurred with all levels of methionine but was more pronounced with 6 g/day. The abomasal infusion of cystine (5 g/day) caused little change in the mass of wool grown, but fibre diameter was decreased slightly. There were no appreciable effects on the strength of wool fibres and no wool was shed. Supplementation of the roughage diet (400 g/day) with methionine at 2 g/day stimulated wool growth, whereas with 6 or 10 g/day the mass of wool grown was unchanged but fibre diameter was markedly reduced. The strength of wool fibres was not markedly influenced by methionine infusions on this diet. The levels of amino acids in blood plasma and in abomasal digesta indicated that the mixture of amino acids absorbed was similar with both the roughage and the wheat diets.
The response to phosphate of two annual pasture species. I. Effect of the soil's ability to adsorb phosphate on comparative phosphate requirement
Authors: Barrow NJ
Published: November 2004

Eleven soils which differed widely in their ability to adsorb phosphate were used in a pot trial to compare the response to phosphate by subterranean clover (Trifolium subterraneum L.) with that by Wimmera ryegrass (Lolium rigidum Gaud.). Response curves were fitted to the yields (log-transformed). The coefficients of the curves were used to calculate both the relative effectiveness of the phosphate and the phosphate required to give a given fraction of the increase in log yield due to phosphate. Overall, the phosphate requirement for the grass was less than for the clover but the two species were affected differently by the soil's ability to adsorb phosphate. The phosphate requirement for the clover increased more rapidly with increasing adsorption by the soil than the phosphate requirement for the grass.
The effect of soil water on root production of peach trees in summer
Authors: Richards D , Cockroft B
Published: November 2004

The effect of soil water supply on peach root production in summer was studied in the Goulburn Valley area of northern Victoria. Under commercial irrigation practice roots do not grow in summer. Field experiments showed that when the soil was kept moist by frequent irrigation (every 3–4 days), the concentration of roots in the surface soil nearly doubled in a single season. Furthermore, observation through glass plates showed that this enhanced root growth occurred throughout summer. When roots were kept inactive in dry soil until midsummer and thereafter irrigated frequently, they immediately responded and grew rapidly. The increased root growth did not impair fruit production. In a glasshouse experiment, with glass-fronted chambers, a relationship between root elongation, root concentration and the drying rate of the soil was found. Each experiment supported the hypothesis that soil drying rate determines the growth of roots in the surface soil. Where there was a high concentration of roots, a low irrigation frequency, and high transpiration, the rate of soil drying was rapid and roots grew slowly. It is suggested that manipulation of root growth by regulation of soil water supply may be an important method of studying root-top interactions.
Inheritance of scald resistance in barley. II.* Resistance genes of group B barley cultivars
Authors: Ali SM
Published: November 2004

The genetic basis of resistance to Rhynchosporium secalis (Oud.) Davis of barley cultivars La Mesita, West China and Sakigake differentiated as group B were determined from F2, F3 and BC1 progenies. The resistance genes identified are situated at different loci from each other. The effectiveness of the identified resistance genes to two isolates of Rhynchosporium secalis was studied under glasshouse conditions in winter and in summer, and also in the field. The inheritance of resistance genes of group B cultivars was found to be greatly influenced by environmental factors.

*Part I, Aust. J. Agric. Res., 26: 243 (1975).
Urinary sediments in sheep feeding on oestrogenic clover. IV.* Indigotin and indirubin in some sediments and calculi
Authors: Nottle MC
Published: November 2004

A blue and a red pigment found in some urinary sediments and calculi from sheep feeding on oestrogenic clovers have been identified as indigotin and indirubin respectively. Possible factors leading to their formation are discussed.

*Part III, Aust. J. Agric. Res., 25: 509 (1974).
The influence of dietary supplements of DL-methionine on the growth rate of wool
Authors: Doyle PT , Bird PR
Published: November 2004

Dietary supplements of DL-methionine (0, 1.9, 3.8, 7.7 and 15.4 g per day) were given to five groups of 15-month-old Merino sheep (five per group) over an 8-week period. The roughage ration given (c. 840 g dry matter per day) comprised oaten chaff (78%), lucerne chaff (20%) and minerals (2%). Significant wool growth responses were obtained (18% above controls) when 3.8 g supplemental methionine per day was given. Changes in the rate of wool growth were paralleled by changes in nitrogen retention. Nitrogen retention was significantly increased above controls when 3.8 g supplemental methionine per day was given. Supplemental methionine did not affect liveweight gains.
Liveweight gains and carcass composition of buffalo (Bubalus bubalis) steers on four feeding regimes
Authors: Charles DD , Johnson ER
Published: November 2004

Twenty buffalo steers were divided into four groups of five and were lot-fed for 86–287 days on nutritional regimes that varied from roughage to high-grain concentrate, and liveweight gains and carcass composition were determined. Mean daily liveweight gains were 0.74 kg (fed on three-quarters pellets + one-quarter hay), 0.67 kg (all pellets), 0.64 kg (three-quarters hay + one-quarter pellets) and 0.56 kg (all hay). Feeding regime had little effect on carcass composition. The proportions of muscle, bone, fat and connective tissue did not vary significantly among the four nutritional groups. The carcass composition of the buffalo steers did not differ greatly from that of a group of buffalo bulls previously dissected by the authors, the major difference being that the steers had significantly more fat (16.0%) than the bulls (10.6%). It was concluded that the carcass composition of the buffalo is relatively resistant to extremes of diet and to castration, and that the species does not show a propensity to fatten under 30 months of age.
Sward tests of some morphological-agronomic groups of Stylosanthes accessions in dry tropical environments
Authors: Edye LA , Williams WT , Anning P , Holm AMcR , Miller CP , Page MC , Winter WH
Published: November 2004

An experiment is described in which 33 accessions of Stylosanthes, comprising 12 morphological–agronomic groups of six species, were grown with an associated grass Urochloa mosambicensis for 3 years in small mown swards at nine different dry tropical environments in northern Australia. Pattern analysis was used to elucidate the major differences in sward performance between accessions and sites and to classify the 33 accessions defined by 54 sward attributes (6 measurements x 9 sites) over 3 years. There was a close relation between the classification of the accessions defined by sward data with a previous morphological-agronomic classification based on spaced-plant data. Among the morphological-agronomic groups tested, S. hamata M–A 28 was outstanding at most sites. However, at the extreme ranges of adaptability, S. scabra M–A 18 was more productive at sites with a growing season of 24–30 weeks, and S. scabra M–A 17 was more productive at sites with one of less than 10 weeks.
Relationships between intramuscular fat and dissected fat in the beef carcass
Authors: Johnson ER
Published: November 2004

Quantitative relationships between total dissected fat and weight of intramuscular fat in nine 'standard muscle groups' and total side muscle were investigated in 18 steer carcasses varying in fatness from 9.1 to 38.9% of chilled side weight. A simple correlation matrix showed that both weight and percentage of total dissected fat were more highly correlated with the proportion by weight of intramuscular fat in total side muscle than in any of the 'standard muscle groups'. Predictions of total dissected fat weight from regressions of the intramuscular fat percentages of 'standard muscle groups' and total side muscle were not as accurate as a relatively simple equation employing fat thickness at the 10th rib together with chilled carcass weight. For all six muscle groups used in regression equations, the percentage of total dissected fat in the carcass was more accurately predicted than total dissected fat weight. Standard muscle group 7 was the most accurate of the muscle groups in predicting total dissected fat weight, and it contained the fewest muscles (five), but they were large, expansive muscles which required extensive trimming. Standard muscle groups 3 and 7 were equally accurate in predicting total dissected fat percentage, but the former was associated with even greater dissection and trimming problems than standard muscle group 7. It is concluded that the use of intramuscular fat weight of muscle groups to improve predictions of carcass fatness is neither practicable nor successful.
Response of two soya bean cultivars to manganese toxicity as affected by pH and calcium levels
Authors: Heenan DP , Carter OG
Published: November 2004

Two cultivars of soya bean (Glycine max) were grown in nutrient solution to test their response to manganese toxicity as affected by pH and calcium levels in the medium. Increasing calcium levels consistently decreased manganese concentration in the shoots, but only decreased manganese toxicity symptoms and increased yields between moderate and high levels of substrate calcium. It is suggested that the higher ammonium/nitrate ratio associated with the low calcium treatments, where part of the calcium nitrate was replaced with ammonium nitrate, more than nullified the effect of increased manganese in the shoots obtained from the low calcium treatments. pH had little effect on concentrations of manganese, iron or calcium in the shoots or on the development of manganese toxicity symptoms. However, as pH increased at high substrate manganese levels, total dry matter yields significantly decreased and levels of manganese in the roots markedly increased. At least part of the greater root manganese at higher pH could have been in the precipitated form, while the increased retention of calcium in the roots may also have influenced manganese retention. Reasons for decreased yields at higher pH are discussed. Environmental conditions appear to have had sonic effect on cultivar response to manganese toxicity.
Effects of dormancy factors on the growth of vegetative buds of young apple trees
Authors: Thompson WK , Jones DL , Nichols DG
Published: November 2004

Controlled temperature conditions were used to investigate the chilling requirements of potted 1-year-old apple trees cv. Jonathan. The rate of bud break, the number of buds growing and extension growth were increased by prior chilling. Temperature effects over the range 2–10°C were greatest at the lower end of the range. Chilling early in the dormant period was less effective than later chilling, and interruption of chilling with periods of high temperature reduced subsequent growth.
The utilization by preruminant lambs of milk replacers containing isolated soya bean protein
Authors: Walker DM , Kirk RD
Published: November 2004

Fifty-nine male crossbred lambs, aged 2–5 days at the start of the experiment, were used in four experiments to compare the nutritive value of isolated soya bean protein (ISP) (Promine D) with cows' milk protein (DSM) in milk replacer diets. In experiment 1, ISP diets of low (0.10 of total energy as protein) or medium protein content (0.25 protein energy) with or without supplements of DL-methionine, were compared with DSM diets. In experiment 2, graded amounts of DL-methionine were added to the medium protein ISP diet to determine the optimum level of supplementation. In experiment 3, butter oil, groundnut oil, medium chain triglycerides (MCT) and coconut fat were added as the sole sources of fat in low protein ISP diets and compared with DSM diets that contained butter oil or groundnut oil. In experiment 4 alginates were added to a low protein ISP diet to improve the suspendibility of ISP in the milk replacer. The addition of DL-methionine consistently improved nitrogen balances of the lambs. The optimum concentration of methionine plus cystine in the medium protein ISP diet was 29.8 ? 7.9 mg per 100 KJ, compared with 22.5 mg/100 KJ in the unsupplemented ISP diet. Low protein ISP diets that contained groundnut oil as the sole source of fat were poorly accepted and poorly utilized. The apparent digestibilities of butter oil (0.950) and MCT (0.958) were significantly higher than those of either coconut fat (0.852) or groundnut oil (0.770). Comparable values for DSM diets were: butter oil, 0.985; groundnut oil, 0.855. The addition of alginates to the medium protein ISP diet prevented the ISP from settling out, but was associated with a reduced intake of the diet, a reduction in nitrogen digestibility and an increase in the moisture content of the faeces. The nitrogen balances of lambs given DSM diets were always higher than those of comparable lambs given ISP diets.
An analysis of climatic environments for plant-breeding purposes
Authors: Boyd WJR , Goodchild NA , Waterhouse WK , Singh BB
Published: November 2004

Variations in the regional means of a number of growing-season climatic variables, and combinations of them, are not highly correlated with the long-term regional distribution of mean wheat yields in Western Australia or with their variation between years. The data suggest that the growing season is characterized by a cyclical alternation of favourable and unfavourable conditions for crop growth. This oscillating pattern varies in amplitude and wavelength as a result of unpredictable 'between'- and 'within'-season variation in the regional distribution of rainfall. In the central zone of the study area, wheat production is subject mainly to between-season variation whilst in more marginal areas yield variation is confounded by opposing and reciprocating within-season effects. The consequences for plant breeding are that specific regional environments expected on the basis of climate do not occur predictably in the short term. It is argued that breeding objectives, selection strategies and regional testing should initially avoid complications associated with specific marginal environments by concentrating on general adaptability within the central zone, which monitors between-season variation only. Subsequent evaluation for additional adaptive features specific to marginal areas should be undertaken.
The inhibitory effect of light on seed development in subterranean clover (Trifolium subterraneum L.)
Authors: Taylor GB
Published: November 2004

Explanations were sought for the poor seed development commonly found in unburied burrs of subterranean clover. In the first of two experiments, the effects of light and of atmospheric moisture stress on seed development in subterranean clover (cv. Daliak) were examined. Burrs produced from spaced laterals were enclosed in plastic tubes variously shaded to permit the entry of 0, 5, 19, 48 and 100% daylight. The tubes were further allocated to two groups. Air was continuously passed through tubes of one group to produce an atmospheric moisture stress, while those of the other group were not subjected to air flow. There was a marked effect of light on seed development. Mean seed weight was reduced from c. 11 mg in the dark treatment to 4 mg at only 5% daylight and to 2 mg in the 100% daylight treatment. Seed numbers were reduced significantly, from four to c. two seeds per burr, in the 100% daylight treatment only. There was virtually no effect of atmospheric moisture stress on either seed set or seed size. In the second experiment, a study was made of the effect of timing of burr burial on seed development processes. Fertilization does not appear to be implicated but both cell division and cell enlargement were influenced by the state of burial and, presumably, by light.
Effect of stocking rate, lambing time and pasture management on wool and lamb production on annual subterranean clover pasture
Authors: Fitzgerald RD
Published: November 2004

Border Leicester x Merino ewes mated to Dorset Horn rams grazed subterranean clover and annual ryegrass pasture in a 2 x 2 x 4 factorial arrangement having two stocking rates (8.1 and 12.3 eweslha); two lambing times—winter (May, June, July), and spring (August, September); and four management systems, viz. set stocking (SS), autumn saving and spring hay cut (AS), replacement of half the pasture by oats or lucerne (ISP), and replacement of half the pasture by both oats and lucerne, a quarter each (2SP). The percentage of lambs born to ewes mated was lowest from May lambing and progressively increased up to August–September lambing. However, although July lambing produced marginally fewer lambs with slower growth rates than August–September lambing, the difference was not significant and the extra time available with July lambing for lambs to reach a marketable liveweight before pasture senescence meant that the earlier lambing treatment actually produced more prime lambs. The set stocking and autumn saving systems resulted in greater annual wool and lamb production than the substitute pasture systems. Any extra fodder available from oats or lucerne in those treatments failed to make up for losses in animal production associated with a reduction in available fodder during the crop preparation phase. Deterioration of annual pasture caused by plant losses associated with intermittent grazing may have reduced production further in substitute pasture treatments. The results suggest that in southern Australia on annual subterranean clover pasture the optimum level of stocking and the pasture management strategy for prime lamb production can be assessed by a careful observation of the botanical succession taking place, especially if the pasture is continuously grazed. The results also suggest that optimum fertility should be foregone in favour of an earlier lambing, in order to provide sufficient time before pasture senescence for lambs to reach a marketable liveweight. The optimum time for lambing for prime lamb production for a particular region will depend on the time of year when the pasture in the region normally matures.
Factors affecting the regrowth of Pennisetum americanum under frequent defoliation
Authors: Ferraris R , Norman MJT
Published: November 2004

Data on the regrowth of pearl millet under a 3-weekly defoliation regime, taken from an experiment at Camden, N.S.W., which involved two cultivars, two planting dates and three cutting heights, were examined in an attempt to determine factors influencing the rate of recovery from defoliation. Over all treatments, there was a positive (P < 0.01) association between regrowth over 3 weeks and the leaf area index of the stubble at the start of the regrowth period, and negative (P < 0 01) associations of regrowth with plant age and with the number of axillary branches. There was no association between regrowth and the total number of live tillers. This may have been due to the presence of decapitated tillers In the count. For late-planted crops, there was a positive (P < 0.01) association between regrowth and temperature.
Effects of a mineral oil spray on the flowering of sweet orange (Citrus sinensis)
Authors: Moss GI
Published: November 2004

Mineral oil spray (white oil), as used on Citrus for the control of insect pests, was found to reduce flowering of sweet orange when applied during flower induction Experiments were earned out with rooted cuttings and on trees In the field However, results with use of the commercial preparation were variable The inhibition was due to the oil component, while the associated emulsifiers enhanced flowering when applied during flower induction.
Genetic differences in the copper nutrition of cereals. I. Differential responses of genotypes to copper
Authors: Nambiar EKS
Published: November 2004

Seven wheat genotypes, one or barley and one of oats were compared for their sensitivity to sub optimal supplies of copper, and their ability to recover from copper deficiency when copper was applied at defined stages of growth Copper deficiency delayed maturity, reduced the straw yield and severely depressed the gram yield In all genotypes. Genotypes differed considerably in their expression of deficiency symptoms, and In then- responses to the rate and time of copper application. For all genotypes, the supply of copper needed for maximum grain yield was significantly higher than that for maximum shoot growth. Halberd wheat and Clipper barley were less sensitive to copper deficiency than wheat cultivars Gabo, Glaive, Pinnacle, Chotilerma, UP-301, Duramba, and oats cultivar Avon. Genotypes with relatively higher yield potential were less sensitive to copper deficiency than those with lower yield potential, and the ability of hexaploid wheal to recover from deficiency increased with the increase in the number of days to heading of the normal plants There was no apparent association between dwarfness and sensitivity to copper deficiency in wheat.
The comparative phosphate requirements of four annual pastures and two crops
Authors: Ozanne PG , Howes KMW , Petch A
Published: November 2004

The levels of broadcast phosphate needed for 90% of maximum production by subterranean clover, Wimmera ryegrass at two levels of nitrogen, wheat and lupins are compared in a field experiment. Two seeding rates, one five times the other, were used to vary the stand densities and yields per unit area of the swards. A total of 180 kg nitrogen/ha was supplied to the wheat and high nitrogen grass plots; the low nitrogen grass plots received 30 kg/ha. Although both the high seeding rates and the high nitrogen applications gave up to double the yield per unit area, they did not significantly change the level of phosphate required for 90% of maximum yield by a given species or mixture. Grown as single species, lupins had the highest phosphorus requirement (202 kg/ha); wheat (118 kg/ha) and clover (107 kg/ha) had similar requirements; while grass with either a low nitrogen supply (58 kg/ha) or a high nitrogen supply (56 kg/ha) had the lowest requirement when measured during flowering. When clover and ryegrass were grown as a mixed sward, the phosphorus requirement (84 kg/ha) was close to the average of those for the pure clover and grass. Both the grass and clover responded to approximately the same level of phosphate when grown as a mixture. The amount of nitrogen fixed by the clover, either as a pure sward or when mixed with grass, increased with increasing phosphate application. We think that the phosphate level required by the grass when grown with clover rather than as a pure sward was an expression of this increased nitrogen supply and not a direct response to phosphate. The levels of phosphate required to produce 90% of the maximum grain yield in the lupin and ear yield in the wheat were similar to the phosphate requirement for 90% of maximum vegetative yield.
Residual effectiveness of phosphorus on white clover on granitic soils
Authors: Holford ICR , Gleeson AC
Published: November 2004

Three field experiments were carried out on highly phosphorus-deficient granitic soils in the northern tablelands of New South Wales to determine the residual effectiveness of phosphorus, and the efficiency of its usage by white clover pastures, in relation to the rate and frequency of application of fertilizer. There was a linear and very large increase in the cumulative yield of white clover up to a maximum rate of about 100 kg phosphorus per hectare. Over the 4 or 5 years of each experiment there was no decrease in the efficiency of usage of phosphorus with increasing initial or cumulative rates of application up to a maximum rate equivalent to the phosphorus adsorption capacity of each soil. Above this rate, loss of efficiency was attributed to leaching of the excess phosphorus. Phosphorus applied at 98 kg ha-1 only in the first year gave near-maximum yields in the second year, but by the fourth year yields had fallen to as low as 50% of the yield from equivalent rates of freshly applied phosphorus. The residual effectiveness was greater than that usually reported in the literature, and this may be due to the unusually low phosphate buffer capacities of these soils. To maintain the high early productivity from a large initial application of phosphorus, a small annual supplementation of 12 kg ha-1 was required.
Sward tests of some Stylosanthes guyanensis accessions in tropical and subtropical environments
Authors: Edye LA , Williams WT , Bishop HG , Burt RL , Cook BG , Hall RL , Miller CP , Page MC , Prinsen JH , Stillman SL , Winter WH
Published: November 2004

An experiment is described in which 48 S. guyanensis accessions, comprising 11 morphological-agronomic (M–A) subgroups, were grown with an associated grass (Urochloa mosarnbicensis or Setaria anceps cv. Narok) for 3 years in small mown swards at up to nine different tropical and subtropical environments in northern Australia. The experiment was non-orthogonal, but could be analysed as three substantially orthogonal subsets; simple ranking techniques were used to explore the complete data set.Significant differences were shown to exist between the M–A groups, but these were less clear-cut than in other Stylosanthes species; the S. guyanensis groups are agronomically more variable. Nevertheless, the results have indicated the existence of five accessions which appear able to outyield any existing cultivar in the appropriate environments. These arc CPI 34911 (M–A group 8A) over a wide range of tropical sites; 40255 (10B) and Q8231 (8A), less wide-ranging than 34911 but outyielding it at a site with a long growing season; and 46590 and 46589C (both 8B), In the high-rainfall subtropics. All would merit more extended trials.
The detection of oestrogenic activity by measurements of nucleic acid concentrations in serial samples of ovine uterine tissue obtained by biopsy
Authors: Little DA , Lambourne LJ
Published: November 2004

The potential occurrence of phyto-oestrogenic activity in tropical pasture species, which are grazed almost exclusively by cattle in Australia, was assessed by a new technique based on changes in the ratio of concentrations of nucleic acids in ovine uterine tissue. Cast-for-age ewes ovariectomized on the 12th day after oestrus were subjected 14 days later to oestrogenic stimulation; samples of uterine tissue were obtained by biopsy before and after the administration of oestrogen. Significant increases in the ratio of nucleic acid concentrations, RNA/DNA, were obtained in response to the administration of 5, 10 and 20 µg stilboestrol dipropionate intramuscularly daily for 3 and 5 days. The variance of the response was mainly affected by the dose of stilboestrol, and a significant effect due to the duration of treatment was detected. It was concluded that the technique will detect levels of phyto-oestrogenic activity substantially below those likely adversely to affect reproduction in cattle.
Response of soybeans to planting date in south-eastern Queensland. III.* Agronomic and physiological response of cultivars to planting arrangements
Authors: Lawn RJ , Byth DE , Mungomery VE
Published: November 2004

Results from five field experiments, designed to evaluate the response of several soybean cultivars to planting arrangement, and conducted at two locations in south-eastern Queensland during 1967–1972, are reported. Response to planting arrangement varied depending on cultivar maturity type, planting date, and availability of moisture during growth. Averaged over cultivars and planting arrangements, seed yields for irrigated soybeans were highest for December plantings, and declined as planting was delayed. A cultivar x planting date interaction was apparent. For December planting dates, yields of all cultivars were generally highest in 50.8 cm rows. A cultivar x plant population interaction occurred, with yields of the later-maturing cultivars maximized at lower plant population levels than for the earlier cultivars. When the planting date was delayed beyond December, yields of all cultivars were maximized in narrow row-high density treatments. Yields of the narrow row-high density late plantings were equivalent to, and in the case of the late-maturing cultivars, greater than, the highest December yields. Wide row widths (101 .6 cm) were consistently lower-yielding, regardless of cultivar and planting date. Seed yields were reduced substantially by periods of severe moisture stress during growth. The relative performance of cultivars of differing phenology depended primarily on the coincidence of periods of severe stress with critical stages of development, viz. pod and seed development. In the environments involving periods of severe moisture stress, seed yields were maximized in row widths narrower than 50.8 cm, and at the lowest plant populations used (c. 95,000 plants per ha). Such treatments most closely approached low density-equidistant spacings in these studies.
Effect of feed quality and stage of lactation on the concentration of glucose in the blood of lactating cattle
Authors: McClure TJ
Published: November 2004

Three groups of dairy cows were fed on: (i) immature forage oats, together with hay and dairy meal (ration A), or (ii) moderately mature forage oats alone (ration B), or (iii) relatively mature forage oats supplemented with dairy meal (ration C), from 2 weeks before until 10 weeks after parturition. The mean concentration of glucose in the blood of the cows fed on ration A did not fall significantly after parturition, but did fall significantly after parturition in the blood of cows on rations B and C. There appeared to be an interaction between feed quality and the stage of lactation in their effects on blood glucose concentration.
Ovulation in ewes given formaldehyde-treated or untreated casein in maintenance-energy rations
Authors: Corbett JL , Edey TN
Published: November 2004

Forty-six Border Leicester ewes and 40 Dorset Horn ewes were individually fed in pens, for a period of mean length 25 days, with amounts of pelleted lucerne and barley that approximately met their energy requirements for maintenance, and contained 14.75% crude protein in the dry matter. Maintenance feeding continued on average for a further 23 days until the ewes were mated, but during this period individual daily rations for one half of each breed group contained 60 g casein that had been treated with formaldehyde; rations for the other ewes were virtually identical except that the casein was untreated. Measurements of blood urea nitrogen, plasma amino acids, and wool growth on the Dorset Horn ewes indicated that the treated casein diet provided the ewes with greater quantities of amino acids than did the untreated diet. The ovaries of all ewes were examined by laparotomy after mating. The mean number of corpora lutea per ewe was 1.6 and did not differ significantly between casein diets, nor did the mean number of ovarian follicles, 1.6, or follicle size. There were also no differences in the numbers of ewes that failed to lamb, or bore single or twin lambs.
The physical distribution of mineral material on forage plant cell walls
Authors: McManus WR , Robinson VNE , Grout LL
Published: November 2004

Data are advanced to show that controlled ashing of plant cell wall material at 500°C for 3 hr provides a convenient method of removing organic matter and permits visual study of mineral material within the plant structure. Evaluation of a range of mature tropical and temperate grass and legume forage species with the scanning electron microscope has shown the existence of a mineralized component over the cell walls. This component is distributed in sheets of thickness varying upwards from c. 0.1 µm and is located on the outer surface of cell walls, possibly constituting a masking layer around digestible organic material of the cell wall. Energy-dispersive X-ray analysis shows the major elements constituting this mineral layer to be phosphorus, calcium, sulphur and potassium.
Effects of Trichostrongylus colobriformis (Nematoda) on the nutrition and metabolism of sheep. IV.* Glucose metabolism
Authors: Roseby FB
Published: November 2004

The effect of infection with Trichostrongylus co!ubriformis on quantitative aspects of glucose metabolism was studied in 12 Merino lambs. Total entry rate, rate of irreversible loss and rate of recycling were measured simultaneously by means of [U-14C]glucose and [3-3H]glucose. The feed intake of all sheep was maintained at 540 g/day throughout the experiment. The total entry rate of glucose in infected sheep was greater than in their controls. There was a smaller difference in the irreversible loss of glucose because of increased recycling of glucose carbon in infected sheep. It was concluded that the rate of glucose synthesis was higher in infected sheep compared with control sheep on the same feed intake, because there was more recycling and possibly increased availability of propionate from the large intestine. However, this increase would not compensate for the reduced intake of glucose precursors by infected sheep fed ad libitum, so the overall effect of T. colubriformis infection would be to reduce glucose synthesis.

___________________
*Part III, Aust. J. Agric. Res., 28: 155 (1977).
Production characteristics of Jersey-Sindhi grades in Sri Lanka
Authors: Buvanendran V
Published: November 2004

Jersey sires were crossed with Sindhi females. F2 five-eighths Jersey and three-quarters Jersey animals were bred from the F1 generation. A pure herd of Ayrshires and three-breed cross animals (with the Bos taurus breeds and one B. indicus breed as ancestors) were also kept contemporaneously with the Jersey x Sindhi crosses. Milk yields of F1 animals were significantly higher than those of F2 and five-eighths animals. Calving intervals were lowest in the F1 animals, while calf mortality was lowest in the three-breed crosses and highest in Ayrshires.
Reduced cervical mucus bioassay response to oestrogen by the ovariectomized ewe after oestrogen treatment during progesterone priming
Authors: Adams NR
Published: November 2004

Ovariectomized ewes were treated with progesterone and oestrogen during a priming period, after which the mucus response of the cervix to trigger doses of 0, 5, 10 or 20 µg of diethylstilboestrol (DES) was determined. The ability of the cervix to respond to DES was diminished if the ewes had previously been given either 15 or 30 µg DES for 9 days during priming with 10 mg of progesterone daily, or if the ewes had been previously treated with 10 µg DES for 12 or 24 days during progesterone priming. Furthermore, the temporal pattern of cervical mucus response to oestrogenic pasture was altered when ewes were primed with progesterone while grazing that pasture. These phenomena made it impossible to measure accurately the oestrogenicity of a pasture when ewes were primed with progesterone for 10 days while on that pasture.Failure to respond to the DES trigger doses was not due to the production and exhaustion of cervical mucus hring priming. There appeared to be two alternative responses by the ewe's cervix to oestrogen, one productive of cervical mucus and the other resulting in a refractory state.
Superphosphate on perennial pastures. II.* Effects of a pasture response on steer beef production
Authors: Curll ML
Published: November 2004

For a 3 year period, superphosphate was applied annually at rates of 0, 62, 125 and 250 kg ha-1 to an established phalaris (Phalaris aquatica)/subterranean clover (Trifolium subterraneum) pasture with a substantial history of superphosphate use. Steers, replaced annually, continuously grazed these pastures so that plant growth responses to superphosphate could be calibrated in animal production and economic terms. Pasture growth rate responses to superphosphate, relative to unfertilized treatments and averaged over 3 years, were 64, 108 and 136% for the 62, 125 and 250 kg ha-1 treatments respectively. Similar proportions of phalaris and subterranean clover were maintained in the unfertilized pasture, and phalaris became the dominant component in the fertilized pastures. Superphosphate significantly increased the level of available pasture and steer growth rates. Steers from the 62, 125 and 250 kg ha-1 treatments averaged, at sale, 70, 98 and 117 kg heavier respectively than those from the unfertilized treatments. Over the experimental period, a twofold reduction in gross margins followed from withholding superphosphate. In contrast, its application in the second and third year led to an average fourfold and sixfold improvement respectively in gross margins. It is suggested that the use of these results to test and improve simulation models of fertilizer systems is the most effective means of establishing guidelines on which to base decisions on current fertilizer policy in other situations.

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* Part I, Aust. J. Agric. Res., 28: 991 (1977).
Formaldehyde treatment of concentrate diets for sheep. II.* Effect on urea synthesis and excretion
Authors: Faichney GJ , White GA
Published: November 2004

The synthesis of urea, its return to the gastrointestinal tract and excretion in the urine were studied in sheep given concentrate diets, untreated or treated with formaldehyde, containing four different protein levels. Rumen ammonia and plasma urea levels increased with protein level and decreased with formaldehyde treatment. Changes in urea excretion were closely related to changes in plasma urea levels. There was a relationship between urea synthesis and rumen ammonia levels, but differences in the amount of urea returned to the gastrointestinal tract did not follow a consistent pattern. When expressed as a percentage of urea synthesized, urea recycling decreased as protein level increased but tended to increase when the diets were treated. The results are consistent with an appreciable fraction of the nitrogen returned to the rumen being in forms other than urea.

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*Part I, Aust. J. Agric. Res., 28: 1055 (1977).
Water-soluble polysaccharide determination as a technique for evaluation of sweet corn maturity
Authors: Darbyshire B , Muirhead WA , Henry RJ
Published: November 2004

A relationship between the non-structural carbohydrate content and the maturity of sweet corn for processing has been established. It is demonstrated that over the period when sweet corn is suitable for harvesting, while moisture content decreases, water-soluble polysaccharide (wsp) levels increase rapidly but soluble sugar concentrations decline only slightly. These results suggest that decreasing sweetness as the sweet corn matures is due to increasing WSP levels masking the sweetness contributed by relatively constant sugar concentrations. The rapid increase in wsp makes measurement of WSP content a sensitive indicator of small changes in maturity. Because of this sensitivity and the important influence of WSP on sweet corn quality, estimation of wsp provides a rapid technique for the accurate determination of sweet corn maturity.
The effect of intravenous administration of phosphorus on phosphorus and calcium metabolism in sheep
Authors: Towns KM , Boston RC , Leaver DD
Published: November 2004

Four Dorset × Merino wethers were given an intravenous infusion of phosphorus at the rate of 1.5 g/day and the phosphorus and calcium balance determined between 5 and 11 days inclusive after the commencement of the infusion. These results were compared with phosphorus and calcium balance measured during a control period. In three of the four sheep the infused phosphorus was recovered in the faeces, but in one animal 0.37 g/day was excreted in the urine. Although the retention of phosphorus and calcium increased marginally during the infusion period, the increase was not significant. The additional phosphorus was therefore quantitatively eliminated from the animal without significantly influencing calcium balance. A theoretical model of phosphorus movement was constructed on the basis that salivary phosphorus excretion is related to plasma phosphorus concentration. In order to account for the observed recovery of phosphorus in the faeces, it was necessary to postulate either a decrease in the intestinal absorption of phosphorus or an increase in the endogenous secretion of phosphorus which was unrelated to the plasma phosphorus concentration.
Production of carcass beef of specified composition in steers of four breeds at three ages
Authors: Charles DD
Published: November 2004

The production of carcass beef, where muscle is 80% and dissectible fat 20%, was determined in Hereford, Angus, Friesian and Charolais X steers at 12, 15 and 18 months old fed ad lib, on a commercial pelleted ration from 9 months old to slaughter. The chilled right carcass sides were dissected into muscle, fat and bone. The carcass beef was the weight of dissected muscle plus fat equal to one-fourth that of muscle so that in carcasses with adequate fat the carcass beef was equal to carcass muscle x 5/4. Carcass beef percentage was highest when carcass fat was one-fourth muscle and decreased by 0.92% with each 1% increase in additional fat. There were small breed differences only at constant fatness. Liveweight and carcass weight were poor indicators of carcass beef because a minimum fatness was required and there was a decrease in carcass beef percentage as fatness increased. No one breed was superior at all the ages of slaughter because of the differences in age to reach the degree of fatness necessary to yield carcass beef 80/20. The breeds also differed in rate of fattening and therefore in the rate of decrease of carcass beef percentage with increase in age. The Herefords and Angus were sufficiently fat to be productive at a younger age than the Friesians or Charolais X but were more wasteful with increase in age. The Friesians appeared to grow for a longer time after they were sufficiently fat to be productive of carcass beef, before they became excessively wasteful. It is suggested that where beef production is measured as the yield of carcass beef of a prescribed composition it would reduce production and processing costs.
Seedling growth characteristics of Stylosanthes
Authors: Gardener GJ
Published: November 2004

Twenty-four lines of annual (S. humilis, S. subsericea, S. sundaica and S. hamata) and perennial (S. viscosa, S. scabra and S. fruticosa) species of Stylosanthes were grown for a 6 week period after sowing, and sampled weekly to determine whether differences in seedling dry weight, earlier exhibited by single members of each species in the field, were (1) representative of each species, and (2) attributable to differences in seed size, relative growth rate (RGR) or distribution of dry matter between tops and roots. Seedlings of all lines of the perennial species had much lower dry weights than the annual species. This was due largely to the low RGR values of the perennials, and to low initial photosynthetic areas of the extremely small-seeded (< 1.3 mg) lines of S. viscosa and S. scabra. Seedling weight at the first harvest was highly correlated with seed weight, embryo weight and cotyledon area regardless of species. With each successive harvest, this correlation was reduced owing to differences in RGR which were independent of seed weight. The poor top growth of the perennial species could not be attributed to increased root growth. In fact, between harvests 1 and 3, the small plants of the perennial species allocated a greater proportion of dry matter to the tops than did the annuals. The perennial species did, however, develop deeper and less-branched root systems than the annuals when both had similar root weights. The results suggest that the perennial species of Stylosanthes may present more problems than the annual species both in establishment and in competition with the vigorous tropical grasses.
Diseases of broad bean (Vicia faba L. major) and green pea (Pisum sativum L.) in Tasmania caused by subterranean clover red leaf virus
Authors: Johnstone GR
Published: November 2004

A leaf-roll disease of broad bean, similar to that induced by bean leaf roll virus (BLRV) in Europe, is common in Tasmania. Subterranean clover red leaf virus (SCRLV) was transmitted to subterranean clover test seedlings by using its most efficient vector, Aulacorthum solani (Kalt.), from 84% of 204 randomly selected affected broad bean plants. The disease was reproduced in broad bean with SCRLV in controlled aphid transmission tests. Effects of infection on yield were severe, as further pod set was markedly reduced after symptoms of infection developed. There was some variation among cultivars in their response to infection. The virus occurred as commonly in green pea crops as in broad bean. In pea it caused a top yellowing, but most commercially grown pea cultivars had some tolerance. Subterranean clover stunt virus (SCSV) caused symptoms in broad bean and pea which were also similar to those induced by SCRLV. However, SCSV was rarely found infecting plants in Tasmanian pea and bean crops. BLRV, SCRLV and SCSV share many properties in common and with some other viruses.