bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of hedging on the productivity of Valencia orange trees
Authors: Bevington KB , Bacon PE
Published: March 2005

The effect of hedging on the productivity of 9- and 17-year-old Valencia orange trees was studied in two trials located in inland irrigation districts in New South Wales. At both sites the trees were double planted in north-south rows, and were hedged on their east and west sides in spring 1969 and again in late spring 1973, at two levels of severity. Light hedging (0.2-0.3 m of canopy removed from each side of the tree) was effective in restricting tree spread into the inter-row space without adverse effects on yield. With light hedging the yield loss in the first season was recovered by increased production in the second season after hedging. More severe hedging caused a significant reduction in cumulative yield. By timing the hedging to coincide with the setting and early development of a potential heavy crop the extent of alternate bearing was reduced. There were no consistent effects of hedging on fruit size.
The effect of cockle-shell grit, dietary level of calcium and EDTA on eggshell quality and laying performance of crossbred hens
Authors: Karunajeewa H
Published: March 2005

The eggshell quality and laying performance of White Leghorn x Australorp hens were measured in a 3 x 2 x 2 factorial experiment involving three levels (3.0, 3.5 and 4.0 per cent) of calcium, two calcium supplements (ground limestone and cockle-shell grit) and two levels (0 and 500 p.p.m.) of EDTA. The basal diet contained 14 per cent meat and bone meal as the sole protein supplement. Maximum eggshell quality was achieved on diets with 3.5 per cent calcium as ground limestone or 3.0 per cent calcium as cockle-shell grit plus ground limestone, respectively. Mortality increased with increasing levels of ground limestone in the diet. The dietary level of calcium had no effect on laying performance from 24 to 48 weeks of age but from 49 to 72 weeks of age, diets with 3.5 and 4.0 per cent calcium depressed rate of egg production (P < 0.05), hen-housed egg production (P < 0.01) and feed intake (P < 0.05) and increased mortality (P < 0.05). Egg weight, liveweight and feathering were not affected by calcium level in the diet but tibia-bone ash content was increased (P < 0.05) by the two higher levels of calcium. A daily intake of 3.5 g calcium per hen was adequate for maintenance of both eggshell quality and egg production. Compared with ground limestone, cockle-shell grit increased egg specific gravity (P < 0.05) and henhoused egg production from 49 to 72 weeks of age when the average daily maximum temperature was 27.2�C. It also increased feed intake (P < 0.05), reduced mortality (P < 0.05) during the 24 to 48 weeks of age period, increased liveweight gain (P < 0.01), final weight (P < 0.05) and feather condition (P < 0.05). EDTA decreased eggshell weight (P < 0.05) and eggshell weight per unit area (P < 0.05).
Evaluation of bred lines of Macroptilium atropurpureum
Authors: Hutton EM , Beall LB , Williams WT
Published: March 2005

Improvement over cv. Siratro in five advanced lines from an M. atropurpureum breeding programme was evaluated at four sites (with two soil-types at one site) during four growing seasons. On all except four of the 20 environment/season occasions all the bred lines produced a dry-matter yield markedly higher than that of Siratro. However, this increase in vegetative vigour was obtained at the expense of some reduction of viable seed addition to the soil, although it was considered that, at least under the conditions of the experiment, sufficient seed of all lines was added to soil for their persistence in pastures. Two of the lines (18 and 19) were extremely versatile, with a good performance at all sites; the others (2, 13 and 15) showed some small degree of differential environmental tolerance. It was concluded that the two most specialized environments (Beerwah and Narayen brigalow) could have been excluded from the experiment without diminishing the results. If only relative line performance had been required, a single season would have sufficed; but for a realistic estimate of yield all four seasons (one unusually wet, one unusually dry and two average) were essential. It is recommended that in future work more attention should be paid to standardizing management procedures over all sites.
Response of some tropical grasses to molybdenum application
Authors: Johansen C
Published: March 2005

The response to Mo application of Panicum maximum var. trichoglume cv. Gatton (panic), Cenchrus ciliaris cv. Biloela (buffel) and Setaria sphacelata cv. Nandi (setaria) was studied at three rates of NO3 supply in pots containing soil that was severely Mo deficient for tropical legumes. There were no growth responses of these grasses to Mo, except for a marginally significant effect in panic at the highest NO3 treatment at the first harvest. These results are compared with Mo responses of legume/grass mixtures in the field and published data showing large growth responses of some temperate grasses to Mo. Application of Mo had no effect on total N concentrations of grass tops but markedly decreased NO3-N concentrations in buffel. Setaria had a greater ability to take up Mo than the other grasses and this was associated with the lower NO3 levels in this species. Critical Mo concentrations for growth of all grasses were below 0.02 p.p.m.
Studies on the supplementary feeding of sheep consuming mulga (Acacia aneura). 4. Effect of sulphur on intake and digestibility, and growth and sulphur content of wool
Authors: Gartner RJW , Niven DR
Published: March 2005

The effect of supplementing sheep fed mulga with sulphur in the form either of molasses, or calcium or sodium sulphate, was examined. Sulphur supplementation increased dry matter intake by 38 per cent without significant differences in digestibility. Liveweight changes were related to intake. Clean wool production was increased by 45 per cent with sulphur supplements (0.48 vs. 0.33 mg cm-2 day-1) but the fibre diameter and the sulphur content of the wool (mean 2.66 per cent) were not influenced by sulphur intake. The cations calcium and sodium had no effect on any responses. Molasses increased feed intake more than calcium sulphate or sodium sulphate did, but the difference was not statistically significant. The extra response in intake to molasses could be due to its contribution of cobalt, as mulga is marginal in this element (0.07 p.p.m.).
Superphosphate and stocking rate effects on a native pasture oversown with Stylosanthes humilis in central coastal Queensland. 2. Animal production
Authors: Shaw NH
Published: March 2005

Liveweight changes of beef cattle were measured over eight years in a grazing experiment on a native pasture (Heteropogon contortus dominant) oversown with S. humilis (T.S.). The pastures were subjected to three levels of molybdenized superphosphate (F0 = nil; F1 = 125 kg ha-2 annually; F2 = 250 kg ha-1 annually plus an extra 250 kg ha-1 initially) in factorial combination with four stocking rates and two sowing methods for T.S. (ground sowing into spaced cultivated strips, or aerial sowing). Stocking rates were gradually increased during the experiment and for the last three years overlapping ranges were used for the three fertilizer levels; the overall range was then from 0.55 to 1.65 beasts ha-1. Superphosphate increased liveweight gain per head in all years. The main effect was in the period of weight gain and the difference between rates of gain on fertilized and unfertilized pastures increased over years. The mean for F, and F, ranged from 370 to 71 0 g head-1 day-1 compared with 270 to 470 g head-1 day-1 for F0. Except for the last year, there were liveweight losses in all three fertilizer treatments in winter; treatment differences then were mostly small, with significant effects in only three of the eight years. F, gave higher annual liveweight gains than F1 in three of the first six years, but by years seven and eight these two treatments were equal. Comparisons with pasture data described in a previous paper showed highly significant linear relations between annual gains per head and T.S. yield (log10 kg ha-1), and it is concluded that this is the main factor in the liveweight response to fertilizer. Increasing stocking rate depressed gain per head in F, in all years (mean of 35 kg head-1 for an increase of 0.5 beasts ha-1). A similar effect occurred in F1 and F2 in early years, but there was virtually no stocking rate depression in F2 in the last two years, and a significant increase for F1 in the final year. This effect is ascribed to the increase in T.S. yield in fertilized pastures at high stocking rates. Sowing method had no effect on animal production.
Harvest pruning of young Sultana vines under various training systems
Authors: May P , Clingeleffer PR , Brien CJ , Scholefield PB
Published: March 2005

Trellis drying of Sultana grapes necessitates the severing of the fruit bearing canes from the vine at harvest time (Harvest pruning, HP). Two experiments have shown that HP of young vines, from the beginning of cropping onwards, caused no greater yield losses than those reported for mature vines, viz 10 per cent. In one experiment, HP gave significant yield reductions over six seasons, amounting to about 7 per cent, apparently due to fewer berries per bunch. Vines harvest pruned only every second year suffered losses mainly in the season following HP. In the other experiment, HP did not cause any loss of yield over four seasons. With or without HP, vines on a 0.9 m and 1.2 m wide T-trellis yielded about 20 per cent more than vines on a 0.3 m trellis, apparently because of better bud burst. Providing vines with two trunks, each producing the crop or replacement shoots only in alternate seasons, did not prevent HP losses. Such vines yielded similarly to one-trunk vines while vines with one trunk and planted in pairs yielded less. A 'split system' of training was used where each vine had all fruiting canes placed on one trellis wire whilst spurs producing all replacement shoots were trained on the other wire, the arrangement alternating down the row from vine to vine. HP of such vines was more than twice as fast as that of conventionally trained vines; other management advantages are discussed.
Performance of calves fed milk from either a normal or artificially induced lactation
Authors: Taylor JW
Published: March 2005

Friesian bull calves approximately five days old were fed milk for six weeks from cows in the third month of normal parturient lactation or from cows induced to lactate by oestrogen-progesterone treatment. There were no differences in liveweight gain, faecal index, reaction to Open Field Test or lethargy index. It is concluded that artificially induced milk is nutritionally equivalent to normal milk and there is no indication from this experiment that it would not be fit for human consumption.
Supplementation of sheep grazing wheat stubble with urea, molasses and minerals: quality of diet, intake of supplements and animal response
Authors: Mulholland JG , Coombe JB
Published: March 2005

Supplements of urea, molasses and minerals were offered for 15 weeks to mature crossbred wethers grazing wheat stubble at Condobolin in central New South Wales. The sheep were then grazed without supplements on a phalaris-subterranean clover pasture for a further five weeks. On the wheat stubble, dead crop residues amounted to more than 4000 kg DM ha-1 and constituted 95% or more of the available plant material throughout the experiment. Diets selected by the sheep contained significant amounts of grain or green plant material only during the first six weeks, while the proportion of dead plant material increased from 66% to 98% of the diet as the experiment progressed. Supplementation had no effect on diet selection. All sheep gained some weight during the first six weeks of stubble grazing, and thereafter lost weight. This loss was reduced from 0.66 kg week-1 to 0.47 kg week-1 with a mineral block supplement, and to 0.37 kg week-1 with supplements of a mineral/urea block, or molasses or molasses/urea licks. Significant differences in mean liveweight occurred between unsupplemented sheep and those offered a mineral/urea block, or a molasses lick. These differences were reduced by half after five weeks on green pasture, due to compensatory gain. Supplementation had no effect on wool production, or on the amount of dead plant material utilized for animal production, which amounted to a mean of about 10% of the quantity initially available. Mean intakes of supplement by groups were close to the desired amounts, i.e. 10 g urea or 50 g molasses sheep-1 day-1, or both, but for all supplements intake varied widely among individual sheep, with the coefficient of variation exceeding 40% in more than half of the recordings. Apart from special circumstances where reduced rates of weight loss may be important, it seems that little benefit will be gained from feeding urea, molasses or mineral supplements to sheep grazing crop stubbles.
Assessment of the genetic potential for pasture purposes of the Psoralea eriantha - patens complex, a native legume of the semi-arid zone
Authors: Britten EJ , Lacy IDe , De Lacy I
Published: March 2005

Four accessions of Psoralea were grown under favourable conditions in a simulated sward trial at the University of Queensland Research Farm, Redland Bay. The accessions, selected on the basis of growth habit, were A1 8, prostrate; A1 5 and A1 13, semi-erect; and A1 84, erect. These were compared with lucerne and Siratro as controls. Dry matter and nitrogen determinations were made at three different harvest intervals and plant densities for a twelve month period. Yields of the Psoralea accessions reflected markedly the harvest regimes to which they were subjected. Highest yields of the prostrate A1 8 come from the six week harvest interval, A1 13 from the three month interval and A1 5 and A1 84 from the six month harvest interval. Highest yields in most cases were obtained from the highest planting density. When the most favorable cutting regimes were compared for each entry, the two highest Psoralea accessions, A1 84 and A1 13, gave yields at the end of the first six months comparable to the lucerne control and greater than Siratro. A184 behaved as an annual and did not recover after cutting at the six month harvest interval. Other accessions showed greater ability to recover after cutting. A1 13 at the 12 month harvest was the highest yielding Psoralea, producing less than lucerne and more than Siratro. The nitrogen content of leaves of A1 13 was less (P < 0.05) than lucerne, but not significantly less than Siratro. Leaf dry matter as percentages of the total were comparable with the two controls.
Lucerne aphid effects on 18 pasture legumes in southern Queensland: a glasshouse study
Authors: Franzmann BA , Scattini WJ , Rynne KP , Johnson B
Published: March 2005

The suitability of 18 naturalized or commercial pasture legumes as hosts of the spotted alfalfa aphid (SAA) (Therioaphis trifolii f, maculata (Monell)) and the blue-green aphid (BGA) (Acyrthosiphon kondoi Shinji) and the effects of the aphids on the growth of these legumes were investigated in uncaged pots in a glasshouse trial. The species and cultivars tested were: Medicago sativa cv. Hunter River, M. truncatula var. truncatula cv. Jemalong, M. truncatula var. truncatula cv. Cyprus, M. scutellata cv. Robinson, M. littoralis cv. Harbinger, M. polymorpha, M. minima, M, lupulina, Trifolium repens cv. Ladino, T. repens cv. Grasslands Huia, T, semipilosum var. glabrescens cv. Safari, T, pratense cv. Grasslands Turoa, T, subterraneum cv. Woogenellup, T, glomeratum, Astragalus hamosus cv. loman, Vicia dasycarpa cv. Namoi, Ornithopus compressus cv. Pitman, Macroptilium atropurpureum cv. Siratro. Medicago spp. and Trifolium spp. supported the greatest populations of SAA and BGA, respectively, although high populations of the latter were supported on most legumes. M. scutellata cv. Robinson and M. truncatula cvv. Jemalong and Cyprus supported a low population of SAA while T. semipilosum cv. Safari was the only Trifolium sp. host. BGA developed on all legumes with lowest populations on O. compressus cv. Pitman, M. atropurpureum cv. Siratro and Vicia dasycarpa cv. Namoi. SAA reduced yields of all Medicago spp, except cvv. Jemalong, Cyprus and Robinson ; all M. littoralis cv. Harbinger and most M. polymorpha plants died. BGA reduced yields of all legumes except cv. Robinson, cv. Namoi, cv. Pitman and cv. Siratro; all cv. loman plants died. Treatment with both aphids reduced yields of all legumes except cv. Namoi, cv. Pitman and cv. Siratro and killed all plants of cv. Harbinger, M. polymorpha and cv, loman. Of the legumes examined, V. dasycarpa cv. Namoi, O. compressus cv. Pitman, M. atropurpureum cv. Siratro and perhaps M. scutellata cv. Robinson are the only cultivars of species which may be expected to produce reasonable yields under combined attack
Insect control with CO2 in a small stack of bagged grain in a plastic film enclosure
Authors: Banks HJ , Sharp AK
Published: March 2005

The use of carbon dioxide, added as dry ice, was demonstrated as a means of disinfestation of bagged wheat and rye enclosed in a PVC membrane. The bag stack was dosed with dry ice giving an atmosphere of about 60% CO2. Carbon dioxide levels were maintained over 22 days with additional charges of dry ice added directly on top of the stack or enclosed within a polystyrene box to regulate the CO2 release rate. A natural infestation of Rhyzopertha dominica with small numbers of other stored product pest species was controlled, with complete mortality of adult insects, but slight survival of some early stages of R. dominica. Some of the hymenopterous parasitoids, Anisopteromalus calandrae and Choetospila elegans, survived the treatment, apparently as pupae. The treatment was successful under conditions where many other methods of pest control were inapplicable because of difficulty or expense of application, as in a small bulk (2.8 tonnes), at low temperature (11-13�C), when the commodity is close to working areas and when there is a requirement for freedom from pesticide residues.
Effects of trellising, crown bunch handling, and the number of oil emulsion and gibberellic acid sprays on harvest-pruned sultanas
Authors: Sarooshi RA , Roberts EA
Published: March 2005

Effects of trellising together with the use of various foliage wire arrangements on the production and quality of harvest-pruned sultanas were studied over 4 years. In one experiment a single wire and four narrow 0.4 m 'T' trellis systems, and in a second experiment four 0.9 m wide 'T' trellis and one 0.4 m narrow 'T' trellis system, were tested. Other treatments superimposed on all trellises included crown bunch removal in early spring or at harvest pruning, one and two alkaline oil-in-water sprays (oil sprays) and gibberellic acid (GA) or no GA spray. There were no differences between the four narrow trellises. Dried fruit yield of these four trellises was greater than that of the single wire by an average of 27%, because of higher bunch and cane numbers. There were also no differences between the four wide trellises except that two of the complex ones had more canes. The narrow trellis NTI (used in both experiments) yielded 27% less than the wide trellises because of fewer bunches per vine, caused by lower cane numbers and fruitfulness. Trellising had no effect on fruit quality and only marginal effects on rate of fruit drying, most probably due to low vigour of the experimental vines. As the complex trellis systems had no advantage over the simpler two wire 'T' trellises, their use in harvest pruning is not advocated. In both experiments two oil sprays produced slightly better fruit quality with faster drying of fruit. Use of two oil sprays is warranted where fruit has to be dried rapidly to minimise risk due to rain damage. Early crown bunch removal did not reduce yield and the best time for bunch removal was 6 weeks after bud burst. Use of GA in harvest pruning is not recommended as it does not improve fruit quality and in some years leads to slower fruit drying.
Tannins in pasture legumes
Authors: Marshall DR , Broue P , Munday J
Published: March 2005

A total of 787 lines or ecotypes representing 179 species were tested for the presence or absence of tannins in their leaves using the vanillin/HCI spot test. Of the 11 3 species of Trifolium included in the survey, only five were found to contain tannins in their leaves and there was no evidence of tannin production in the 530 ecotypes of T. subterraneum tested. Our results, in agreement with previously published surveys, indicate that species with tannins in their leaves are very common in the tribe Hedysareae, less common in the tribe Loteae and rare in the other tribes of the Leguminosae, particularly the Trifolieae, which contains most of the important temperate pasture legumes. These findings are discussed in relation to the problem of developing, by interspecific hybridization or by induced mutation, low bloat risk pastures for temperate Australia.
Effect of stocking rate and grazing frequency on a Siratro (Macroptilium atropurpureum)/Setaria anceps cv. Nandi pasture
Authors: Jones RM
Published: March 2005

Five stocking rates, ranging from 0.8 to 2.8 beasts ha-1, and three frequencies of grazing were imposed on a five-year-old Siratro (Macroptilium atropurpureum)/Setaria anceps cv. Nandi pasture at Samford, south-east Queensland. The three grazing frequencies involved grazing for four days every three, six or nine weeks. Plots were individually grazed from 1972 to 1976 and the residual effect of treatments was measured over a grazing-free period in 1977. Within the three week grazing frequency both Siratro yield and total yield declined markedly with increased stocking rate, with an increased invasion of prostrate species such as blue couch (Digitaria didactyla). The decline in Siratro yield at higher stocking rates was less marked in the nine week system where there was much less invasion of prostrate species. However, it is suggested that the value of rotational grazing with a long rest period as a means of maintaining Siratro productivity could be largely at stocking rates where the pasture is overgrazed in terms of animal performance. Siratro density and seedling regeneration were largely unaffected by treatment and there was a good recovery of Siratro in the heavily grazed treatments during the grazing-free period at the end of the experiment. However, Siratro soil seed reserves declined with increased stocking rate and there was a much greater decline in flowering and seeding. On this basis it is predicted that if grazing treatments had been continued the heavily grazed pastures would eventually have reached the stage where Siratro would not recover with spelling.
Ensilage from alkali-treated roughages
Authors: McManus WR , Grout LL , Robinson VNE , Southwell-Keely P , Woodhart PN
Published: March 2005

Three experiments examined the chemical properties and digestibility of silage made from ground wheaten straws and a ground mature legume hay treated with alkali, the effects of type and concentration of alkali, heating during the initial alkali-reaction phase, and the effect of a grain supplement on initiation and maintenance of fermentation. All silages opened in good condition. Initial (1 1/2 hour) pH values for alkali-treated silages were high : 5% NaOH, 11.5; 1.25% NaOH, 9.1 ; 1.25% NH4OH, 9.8 c.f. 6.9 for non-alkali control silages. Final (day 41) pH values for the 4% and 5% NaOH treatment ranged from 6.24-4.86. Inclusion of grain at the start of the process generally favoured early decline in pH values at 70 hours, but had no marked effect on the resultant product at 41 days. Inclusion of grain did not appear to be warranted since, in experiment 1, substantial quantities of acetic acid (0.73-2.33 g 100 g-1 silage DM) and of lactic acid (1.08-1.50 g 100 g-1 silage DM) as well as some propionic acid were found in alkali-treated roughage ensiled alone. These values were greater than for control (no alkali) silages not receiving grain, and indicate that alkali solubilization of hemicellulose occurred, with subsequent fermentation. Alkali treatment increased the digestibility of wheat straws by 60 to 80%; but it did not alter that of alkali-treated mature siratro hay. NH4OH was less effective than NaOH in increasing silage dry matter digestibility. It was concluded that potentially useful silage can be formed from alkali-treated roughages despite the initial highly alkaline environment. The results indicate that neither heating during the main alkali reaction phase nor the inclusion of grain are necessary, either for the initiation of useful fermentation or for the formation of a useful product.
Ethylene dibromide and inorganic bromide residues in oranges after fumigation and storage
Authors: Singh G , Rigney CJ , Gilbert WS , Wild BL
Published: March 2005

Levels of residues of ethylene dibromide (EDB) and inorganic bromide were measured in oranges that had been fumigated by a new EDB fumigation schedule, for the control of Queensland fruit fly. This schedule is based on 24 g EDB m-3 at 20�C for 2 hours. The fumigation was conducted in 0.28 m3 chambers with 40% loading. After fumigation the fruit was held at the fumigation temperature for 24 hours then stored at 6�C for a further 27 days to simulate export conditions. EDB residues in excess of the 0.5 �g g-1 Australian NHMRC limit were recorded during the first 14 days, but by 28 days no EDB residues were detected. Inorganic bromide residues were well below the 30 �g g-1 NHMRC and Codex limits but after 28 days they approached, and occasionally exceeded the 10�g g-1 USFDA limit. Fruit that is held at ambient temperatures for 24 hours and then exported at lowered temperatures should have acceptable EDB levels after two weeks although inorganic bromide levels could exceed some overseas tolerances.
Crossbred lamb growth and carcase characteristics of some Australian sheep breeds
Authors: Cotterill PP , Roberts EM
Published: March 2005

A breed comparison involving 31 2 crossbred progeny of three breeds of sire (Poll Dorset, Suffolk, and Lincoln) and five breeds of dam (Dorset Horn x Merino, Border Leicester x Merino, South Australian Merino, and Peppin Merino) was made between 1973 and 1975 in the western Riverina of New South Wales. The lambs were fed a post-weaning feedlot ration at one of two levels and were slaughtered when they reached 35 kg liveweight. Characters measured were: pre-weaning and postweaning growth rate, dressing percentage, carcase length, carcase leg length, kidney + pelvic fat weight, eye muscle length and depth, rib fat depth, and leg + loin fat and muscle percentage. Carcase characters were adjusted to a constant carcase weight. Important breed differences were those associated with rib fat depth and growth rate. The Suffolk- BL x M cross had high pre-weaning and post-weaning growth rates, but BL x M dams produced lambs with greater rib fat depths. The Suffolk-DH x M and Suffolk-DR x M crosses represented the best compromise between rib fat depth and growth, but their post-weaning growth rates were substantially less than the Suffolk-BL x M. These breed differences for rib fat depth and growth rate were not dependent on the level of post-weaning nutrition.
Nitrogen and phosphorus nutrition of dryland grain sorghum at Katherine, Northern Territory. 4. 15-nitrogen studies on nitrogen carrier and method of application
Authors: Myers RJK
Published: March 2005

The effect of nitrogen source and method of application on yield and N uptake of dryland grain sorghum was studied, using 15-nitrogen labelled fertilizers. The nitrogen sources were ammonium sulphate, ammonium nitrate and urea, and the methods were banded, mixed and split application, using a rate of 50 kg N ha-1 throughout. The experiment was conducted over two wet seasons, 1970-71 and 1971-72. Method of application increased yield and nitrogen uptake in the order banded > mixed > split. Source of nitrogen resulted in the order ammonium sulphate = ammonium nitrate > urea. In the drier season, urea behaved somewhat differently, i.e. banded urea > banded ammonium nitrate= banded ammonium sulphate. Calculation of percentage recovery in general confirmed these results. It was concluded that nitrogenous fertilizer is more effective when banded, and that urea was a less effective source of nitrogen than the two ammonium salts. The results obtained with 15-nitrogen revealed a significant treatment effect that was not apparent in non-tracer experiments namely, the poor performance of urea in the second year. Because of its greater sensitivity, and because it identifies the nitrogen derived from fertilizer, the 15-nitrogen technique has scope for use in field experiments comparing fertilizers and cultural techniques.
Tolerance of mung beans (Vigna radiata) to bentazone
Authors: Felton WL
Published: March 2005

An experiment done in 1977 indicated that mung bean yield was reduced after spraying with bentazone. A more detailed study in 1978 with spraying times at 3, 6 and 9 weeks after sowing showed that in both Berken (green gram) and Regur (black gram) phytotoxicity was most severe when spraying was near the commencement of flowering, i.e. the 6 weeks spraying time. Visual leaf burning ratings after each spraying time indicated that Regur was more sensitive to bentazone than Berken. This was also shown by the grain yield being reduced more with Regur than Berken for bentazone applications at 3 or 9 weeks after sowing. Where two applications of bentazone were made a large reduction in yield occurred if one of the applications was at 6 weeks after sowing. Again, applications at 3 + 9 weeks affected Regur more than Berken. Bentazone influenced yield most by reducing the number of pods per plant, but there was also a significant reduction in the number of seeds per pod. Grain size was smaller with increased and repeated rates of bentazone with Regur, but larger with Berken.
The positive response of cattle to sulphur and sodium supplementation while grazing Stylosanthes guianensis in north Queensland
Authors: Hunter RA , Siebert BD , Webb CD
Published: March 2005

The experiment showed that on a euchrozem soil in north Queensland there is a dual deficiency of both sulphur and sodium for growing steers grazing Stylosanthes guianensis pastures in the dry season. The net gain of steers supplemented with both sulphur and sodium (26 kg) was significantly higher than that of steers supplemented with sulphur alone (6 kg), sodium alone (-16 kg) and unsupplemented steers (-9 kg). Steers supplemented with both elements did not decline in liveweight whereas all other steers experienced a lengthy period of liveweight loss.
Factors affecting response to urea-molasses supplements by yearling cattle in tropical Queensland
Authors: Winks L , Laing AR , O'Rourke PK , Wright GS
Published: March 2005

Two experiments were conducted over a five-year period in north Queensland to examine : 1. the effects of supplements of molasses, phosphoric acid, superphosphate, mono-ammonium phosphate, urea or biuret on liveweight performance of yearling cattle during wet and dry seasons, and 2. the effects of different urea levels (28, 56 and 84 g) in the urea-molasses supplement on dry season performance. Responses to urea-molasses or biuret-molasses occurred in all years after May when faecal nitrogen level fell below 1.3%. In three of the four dry seasons studied, maximum response occurred with the lowest level of urea, 289, in the urea-molasses supplement. Responses occurred up to 849 urea in the remaining year. Compensatory growth during the following wet season reduced liveweight advantages in all years. A faecal nitrogen level of 1.3% should be a useful critical value for feeding urea-molasses supplements in the northern spear grass region.
Response of a conventional and a semi-dwarf wheat, and rape, to superphosphate
Authors: Dann PR , Edwards CBH
Published: March 2005

The effects of seven levels of superphosphate (nil, 40,80,120, 200 and 300 kg ha-1) on Eagle, a conventional wheat, and Condor, a semi-dwarf wheat, and Oro rape, were studied in 1975 and 1976 near Yass, New South Wales. The experiments also provided limited information on the combined effects of nitrogen fertilizer (70 kg N ha-1) and wheat sowing rates (30 and 60 kg ha-1). In both years the response to superphosphate by the two wheats was similar, the highest superphosphate rate more than doubling yield, but the response by the rape was much less. Condor outyielded Eagle by 32%, and Oro by 63%. Wheat yields were 22% greater at the higher sowing rate. In 1975, nitrogen reduced wheat yields by 23%. There was no residual effect on 1975 fertilizer treatments on crops sown in 1976. The effect of increasing superphosphate rates was due to the production of more spikes per hectare; the heavier sowing rate also increased this yield component. The superiority of Condor over Eagle lay in the production of more, and greater weight of, grains per spike.
The superokra leaf gene and short-season cotton breeding
Authors: Thomson NJ
Published: March 2005

The performance of superokra leaf backcross progenies was compared with their normal leaf recurrent parent in two experiments in two successive seasons at Narrabri Research Station in the Namoi River Valley of New South Wales. The first experiment used standard 1 m row spacing and the second both standard and twin-row spacing (two rows sown 25 cm apart on 1 m beds). Other varietal comparisons including short-season and standard types, and normal and superokra leaf types were also made. The mean yield of 220 superokra progenies was 8.4% less than their recurrent parent in the first experiment. The mean yield of 14 of these was 1.2% greater in the second experiment. The superokra leaf progenies were earlier maturing and had a higher lint percentage. Strength and fineness of the progenies compared with the parent varied between experiments. Although mean staple length of the superokra leaf progenies was shorter than the recurrent parent it was demonstrated that selection for longer staple without yield sacrifice was feasible in the backcross population. All short season varieties tested had deficiencies of yield or quality compared with desired standards. The normal leaf Tamcot SP-37 and the superokra leaf M8 variety appeared to have the best combination of earliness and other attributes. There were no significant variety interactions with row spacing. Further study is needed to clarify the usefulness of the superokra leaf gene, because of quality deficiencies and apparent greater instability of varietal performance associated with the gene.
Effectiveness of single and annual applications of potassium fertilizer on mown pasture in southeastern South Australia
Authors: Meissner AP , Clarke AL
Published: March 2005

In south-eastern South Australia, experiments lasting three years were conducted at 22 sites to compare the effects of single and annual applications of KCl on mown subterranean clover-rye grass pastures. Data from the sites were analyzed using the model
Further studies on the use of 2-chloroethyl-phosphonic acid (ethephon) as a thinning agent for apples
Authors: Veinbrants N
Published: March 2005

In a series of experiments the growth regulator 2-chloroethylphosphonic acid (ethephon) at concentrations from 50 ppm to 400 ppm was applied at various stages during and after flowering to apple cultivars Golden Delicious, Gravenstein, Jonathan, Richared and Starkrimson. On the heavy setting Golden Delicious, Gravenstein and Jonathan cultivars, adequate thinning and satisfactory fruit size was obtained when ethephon at 100 ppm was applied at or shortly after full bloom, followed by naphthalene acetic acid. On the lighter setting Richared and Starkrimson cultivars, one ethephon spray at 100 ppm applied at or shortly after full bloom resulted in adequate thinning. All fruit were eliminated on Jonathan, Richared and Gravenstein cultivars when ethephon was applied at 400 ppm, 300 ppm and 200 ppm, 36, 35 and 42 days after full bloom, respectively.
Non-volatile nematicides for control of burrowing nematode in banana plantations in north Queensland
Authors: Broadley RA
Published: March 2005

In a field trial which started at planting, Radopholus similis was controlled by fensulfothion applied at 2.0 g a.i. stool-1 in June and December each year for 4 years. Ethoprophos, fenamiphos and oxamyl applied at the same rate and times were less effective but they did reduce the rate of increase in numbers of nematodes. All treatments increased yields, especially in the third and fourth bunch cycles. The increase was due to larger bunches and to fewer plants falling over. Yields over the entire period were increased by 44% with fensulfothion, 29% with fenamiphos and ethoprophos, and by 21% with oxamyl. In three further trials which were started in the second or third bunch cycles, fenamiphos applied at 2.0 g a.i. stool-1 six times a year gave better nematode control than when it was applied three times a year, or than ethoprophos applied at 6.0 g a.i. stool-1 twice a year. Yields were increased by up to 60%.
Residues of amitraz in the tissues, milk and butter of cattle dipped in Taktic
Authors: McDougall KW , Heath AB , Black RR
Published: March 2005

Residues of amitraz in the tissues of steers slaughtered 24 and 48 hours after dipping in Taktic � (0.025% amitraz) were <0.02 mg kg-1. Milk and butter residues from cows dipped in Taktic reached a maximum of 0.01 and 0.1 7 mg kg-1, respectively, 6 hours after treatment, declining to 0.01 mg kg-1 2 days after treatment. Residues in butter collected during a 3-week period from a local dairy products factory were less than 0.01 mg kg-1. Some of the herds supplying the factory were dipped in Taktic.
The effects of phosphorus, sulphur and stocking rate on the yield, chemical and botanical composition of natural pastures, North-West Slopes, New South Wales
Authors: Lodge GM , Roberts EA
Published: March 2005

The effects of phosphorus (P), sulphur (S) and stocking rate on the dry matter yield, and chemical and botanical composition of natural pasture were examined from November, 1971 to May, 1976 in a 20 point central composite design. P and S were applied annually at five levels (0, 6, 15, 23, 29 kg P ha-1; 0, 14, 34, 54, 67 kg S ha-1) and the plots were grazed continuously at five stocking rates (2.2, 3.2, 4.8, 6.3, 7.3 dry ewes ha-1). Each of the factors, P, S, and stocking rate affected total dry matter. At 4.8 and 6.3 sheep ha-1 the optimum rate of P was 15 kg ha-1, but at 3.2 sheep ha-1 it increased from 15 kg ha-1 to 23 kg ha-1 over the period. S had little effect on yield at the start and end of the experiment, but in between its effect depending on stocking rate; at 3.2 sheep ha-1 low levels (54 kg ha-1) were needed. The quantity of green grass and legume was low in winter and was not consistently affected by any of the factors. The level of N in the green grass remained at less than 2%. Over the period of the experiment the basal cover of perennial grass and the frequency of annual legume declined, while the percentage of bare ground and annual grass increased. These changes over time could not be related to any of the factors, except that the percentage of A. ramosa declined at the higher stocking rates. In some years high stocking rate decreased the percentage of A. ramosa and S. variabilis, and increased that of C. truncata, D. linkii, K. phleoides and T. glomeratum. In terms of pasture yield, fertilized perennial grass pastures on the North-West Slopes have potential carrying capacities of at least 4.8 dry sheep ha-1. However, to support this high stocking rate without significantly affecting pasture yield high levels of S, around 54 kg ha-1, and moderate levels of P, around 15 kg ha-1, are required. At this higher stocking rate no major changes in botanical composition occurred.
Nitrogen transformations in a soil of the Lower Burdekin, Queensland. I. Mineral nitrogen and redox potential under rice
Authors: Reid RE , Waring SA
Published: March 2005

A small plot field experiment was carried out to investigate the effects of 0, 60 and 120 kg N ha-1 as ammonium sulphate and 8, 4 and 3 irrigations before permanent flooding on soil mineral nitrogen and redox potential under rice. The soil was reduced to about 360 mV on some occasions before permanent flooding 39 days after sowing but no significant irrigation treatment effects occurred. After permanent flooding, redox potential at pH 7 declined to stabilize at around 120 mV, in the range where denitrification should occur. Significant differences in soil ammonium occurred between nitrogen treatments throughout most of the experiment. Initial recovery by soil analysis was almost complete but soil ammonium remained below 5 kg N ha-1 in all treatments after the first 53 days. Fertilizer addition significantly increased soil nitrate levels 18 and 27 days after sowing. Both nitrogen treatments significantly increased grain yield. Maximum soil nitrate accumulation occurred 27 days after sowing. It was reduced from 11 kg N ha-1 in treatments with 3 and 4 irrigations, to 6 kg N ha-1 in the 8 irrigations treatment. This difference may not indicate increased denitrification as irrigation treatments did not significantly affect grain yield. After the first few days of permanent flooding, soil nitrate remained below 3 kg N ha-1.
Nitrogen transformations in a soil of the Lower Burdekin, Queensland. 2. Laboratory incubation studies
Authors: Reid RE , Waring SA
Published: March 2005

Two laboratory incubation experiments were carried out to investigate the relation between soil water, Eh 7, nitrification and denitrification and to examine the relation between pH and nitrification. Samples were incubated for 16 days under aerobic and waterlogged conditions with 50 mg N kg-1 of added nitrate or ammonium. Apparent denitrification on waterlogging was rapid with 50% of nitrate disappearing in three days, but the presence of more than 7 mg N kg-1 as nitrate prevented Eh, falling below 270 mV. An initial wetting to 0.1 bar tension after drying and grinding caused apparent denitrification but a subsequent wetting to the same tension did not. If high nitrate levels occurred in the field, denitrification losses would be important. Net mineralization and nitrification were independent of soil water in the range 2 to 30% gravimetric. Samples of a pasture soil of initial pH about 4.2 were incubated aerobically with added ammonium and increasing amounts of K2CO3 to increase pH. Nitrate production increased with increasing pH and the relation between pH and nitrate production changed between pH 5.0 and 5.1. Denitrification losses from ammonium-containing fertilizers on waterlogging will be reduced if low pH has inhibited nitrification.
Effect of time of application of herbicides on the long-term control of St. John's wort (Hypericum perforatum var. augustifolium)
Authors: Campbell MH , Dellow JJ , Gilmour AR
Published: March 2005

The effect of time of application of herbicides on the long-term control of St. John's wort was investigated at Tuena, New South Wales. The herbicides used were: 2,4-D, 2,4,5-T, 2,4-D -i- 2,4,5-T, picloram + 2,4-D, and glyphosate. Each of these was applied in February, May, August and November, 1976, and regrowth of wort monitored until February 1978. The percentage ground cover of unsprayed St. John's wort varied between 75% and 85% over the experimental period. Initially all herbicides reduced the ground cover of St. John's wort from over 75% to less than 15%. Thereafter the regrowth of wort depended on the long-term effect of the herbicides. At the final assessment in February 1978, the most effective herbicide treatments were: from the February and May applications, glyphosate and picloram + 2,4-D; from the August application, picloram + 2,4-D; and from the November application, picloram + 2,4-D, 2,4-D + 2,4,5-T and 2,4-D.
Budburst in Sultana grapevine as influenced by salinity and rootstock
Authors: Downton WJS , Crompton AW
Published: March 2005

The time to budburst in Sultana grapevine growing on its own root system, or else grafted to Dogridge, 161 3, Harmony, Ramsey (often incorrectly referred to as Salt Creek) rootstocks, was studied in plants that had been irrigated with 0, 12.5, 25, 50 or 75 mM solutions of chloride salts under glasshouse conditions during the previous growing season. Budburst was delayed on scions grafted to Ramsey and Dogridge rootstocks. Increased chloride concentration within canes was negatively correlated with time to budburst for all of the rootstock combinations. Accounting for temperature variation during the period of budburst did not affect the relation between time to budburst and chloride concentration within canes. Correlation of mean time to budburst (both on a day basis and a temperature summation basis) with mean chloride content for each rootstock at each level of salt treatment yielded a linear relation (P < 0.001), in which 64-68% of the variability in time to budburst was accounted for by chloride concentration in canes. An increase of 0.1% in cane chloride advanced budburst by 4.2 days and reduced temperature summation to budburst by 327 degree-hours.
The relation between mating activity of rams in pens and subsequent flock mating performance
Authors: Kilgour RJ , Whale RG
Published: March 2005

The serving activity of seven rams in one 20-minute pen mating test followed by two one-hour pen mating tests was recorded. The mating performance of each ram during a single-sire flock mating was subsequently monitored. Mean number of services in the two one-hour pen tests gave the best prediction of the number of ewes inseminated during flock mating (r = 0.88, P < 0.01). The number of services in the 20-minute test gave a poor prediction of the number of ewes inseminated (r = 0.30). The total number of services during the first 20-minutes of the two one-hour tests (2x20-minute tally), the number of services during the 20-minute test and the first 20 minutes of the first one-hour test (2 x 20-minute tally) and the number of services during the 20-minute test and the first 20 minutes of the two one-hour tests (3x20-minute tally) were only moderately correlated with number of ewes inseminated (r = 0.67, r = 0.47 and r = 0.64, respectively). These results explain why other workers, using combinations of 20-minute tests, have failed to demonstrate a relationship between pen mating tests and flock fertility. The results further show that a measure of the serving activity of rams in pens can be used to identify rams that are capable of mating large numbers of ewes, and that the development of a commercially applicable test is worthwhile.
Effect of different levels of the supplements lupin grain, lucerne, wheat, and wheat with urea and sulphur fed during mating in February to Border Leicester x Merino ewes in north-east Victoria
Authors: Kenney PA , Reeve JL , Baxter RW , Cumming IA
Published: March 2005

The use of supplements for four weeks beginning one week before joining from February 7 to April 1 was examined in an attempt to increase lambing rates. Four supplements (lupin grain, freshly cut lucerne, wheat, and wheat with 3% urea and sulphur) were fed at four rates (0, 0.1 7, 0.34, and 0.51 kg day-1/ewe) to a flock of 1200 maiden Border Leicester x Merino ewes grazing annual pasture at the Rutherglen Research Station in north-eastern Victoria. For every 0.2 kg of lupin fed per day the liveweights, ovulation rate and lambing rate of ewes increased by 1 kg, 0.06 and 0.03 per ewe joined, respectively. The mean increase in wool growth for ewes fed lupins, wheat, and wheat with urea and sulphur was 39, 26 and 37%, respectively. Feeding of lucerne did not affect any attributes measured. The intake of supplement by ewes fed wheat based supplements at the higher rates appeared to be more variable between ewes than the intake of the ewes on other treatments. This was indicated by the greater variability in liveweight gain of the ewes fed wheat at the higher rates. Results show that of the supplements used, lupins was the only one which if fed at mating in February, could be expected to substantially improve reproduction.