bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduction of testicular parenchyma at marking: effect on lamb growth, carcass fatness and sexual development
Authors: Hopkins DL , Jackson RB , Saunders KL
Published: March 2005

Growth and carcass parameters were studied for 296 lambs comprising 141 males and 155 ewes. The males were either castrated (wethers) or vasectomised and hemicastrated with the parenchyma of the retained testicle reduced (cryptorchids), or they had the parenchyma of both testicles reduced (rams). Wether and ram lambs grew at a similar rate, the latter group growing significantly (P<0.05) faster to first slaughter than cryptorchid and ewe lambs. Ewe lambs grew significantly (P<0.05) slower than those from the other groups. Ewe lambs were significantly (P<0.05) fatter at slaughter than lambs in all other groups, and wether lambs were fatter (P<0.05) than the cryptorchid and ram lambs. Sexual competency of the cryptorchid and ram lambs was assessed by testicle examination, which showed that the cryptorchid lambs were not likely to produce viable sperm. In contrast, there was evidence that the treatment applied to the ram lambs would not prevent production of viable sperm, and they had the potential to sire lambs. This fertility was attributed to the retention of the scrotal sac. The technique used for the cryptorchid lambs involving scrotal ablation was deemed to offer the most potential in terms of lean tissue growth tempered against sexual competency and development of undesirable male characteristics.
Selecting for nutritive value in Digitaria milanjiana. 4. Milk production from an elite genotype compared with Digitaria eriantha ssp. pentzii (pangola grass)
Authors: Lowe KF , Moss RJ , Cowan RT , Minson DJ , Hacker JB
Published: March 2005

An elite genotype of Digitaria milanjiana, which had been selected on the basis of improved leaf digestibility, was compared with pangola grass (Digitaria eriantha ssp. pentzii, formerly Digitaria decumbens) in terms of milk production, at Mutdapilly in south-eastem Queensland. Unsupplemented Holstein-Friesian cows grazed nitrogen-fertilised, irrigated swards of 2 grasses using a switch-back experimental design. Pasture management and stocking rate were adjusted to provide the animals with 15 kg of green leaf (on a dry matter basis) per cow per day, so that any differences in milk yield could be attributed to differences in leaf quality rather than to total dry matter yield. Cows grazing the selected genotype produced 0.9 kg more milk, 0.07 kg more butterfat and 0.05 kg more protein per cow per day (5.8, 13.0 and 10.9%, respectively) than those grazing pangola grass. These increases were associated with a small increase in leaf digestibility, a faster rate of breakdown of leaf (in an artificial masticator) and a higher proportion of leaf in the diet chosen by the cows grazing the selected genotype. The results of this experiment demonstrate that a tropical grass selected on the basis of digestibility increased milk production of grazing cows. However, factors other than higher digestibility (such as leafiness) contributed to the improvement in production over that from pangola grass.
Implications of soil type, pasture composition and mineral content of pasture components for the incidence of grass tetany in the South East of South Australia
Authors: Lewis DC , Sparrow LA
Published: March 2005

The occurrence of grass tetany related deaths in cattle grazing pasture in the South East of South Australia is related to soil type. The greatest losses occur on the solodised solonetz soils, with few, if any, on the rendzina or siliceous sand soils in the region. Pastures from 3 soil types were sampled on 2 occasions during the growing period, and soils were sampled once. Comparisons were made for the pasture components of potassium (K), calcium (Ca) and magnesium (Mg) concentrations in soils, and K, Ca, Mg, nitrogen (N) and sulfur (S) concentrations in plants. In the July sampling, the mean herbage K/(Ca + Mg) ratio for both annual and perennial grass species grown on the solodised solonetz soils exceeded 2.2 but was below 2 for the other 2 soil types. At the same time the mean K/(Ca + Mg) ratio for soil-extractable cations was 0.10 for the solodised solonetz soils but only 0.058 and 0.025 for the rendzina and siliceous sand soils. A critical value for the K/(Ca + Mg) ratio for the soil extractable cations of 0.07-0.08 is suggested. Of the 22 sites in the investigation, grass tetany deaths had occurred on 9 within the previous 5 years; all of these were classified as solodised solonetz soils. Deaths were reported in late autumn and winter, and in all cases the dominant pasture species growing at these sites in July were grasses. It is suggested that deaths ceased in spring because there was either a change to legume dominance or an increase in air temperature.
Productivity and profitability of steers fed hay on pasture of annual species
Authors: Hamilton D , Maden JJL
Published: March 2005

In 3 experiments, young steers stocked at several rates on annual pasture were fed hay at different levels during late autumn and winter and slaughtered at the end of spring. Hay was provided to increase or to maintain liveweight, or at 1.0 or 1.5% of mean initial liveweight daily, for periods of different length. Carcass weight was only increased with hay feeding where the late autumn and winter weight change of the control steers was <-48 kg for the maintenance treatment and <5 kg for the gain treatment. Varying the length of the hay-feeding period in an attempt to influence the animals desire to graze the short winter pasture did not affect the response per unit of hay. Where carcass weight was increased with hay feeding, the average amounts of hay provided per steer, and the conversion ratios to carcass weight, were 391 kg and 13.3: 1 for maintenance treatment and 727 kg and 16.5: 1 for the gain treatment. The most profitable practice for purchased hay appears to be stocking at a rate that achieves the preferred standard of carcass in most years and providing hay only in years of very poor pasture growth.
Long-term persistence of subterranean clover (Trifolium subterraneum) cultivars in south-western Victoria
Authors: Clark SG , McDonald RM , Street HC
Published: March 2005

The long-term persistence of 6 subterranean clover (Trifolium subterraneum) cultivars was determined by sampling seed from 2 experiments at Hamilton and Beeac in south-western Victoria, 8 or 12 years after sowing. For most of this period the plots were managed as part of the surrounding pasture and were closely grazed by sheep. Herbage yield measurements were made and seed was collected from each plot and grown in a glasshouse, in order to identify the cultivar(s) present. Cultivars used were Yarloop, Trikkala, Larisa and Meteora (spp. yanninicum), and Mount Barker and Woogenellup (spp. subterranean). At both sites, plots sown to Trikkala and Larisa had the greatest seed banks and experienced the lowest level of invasion by other cultivars or ecotypes. Mount Barker and Yarloop appeared to have persisted at low levels; their plots were moderately invaded. Plots sown to the unsuccessful Woogenellup were heavily invaded and contained only a small seed bank of Woogenellup seed. Eight to 12 years after sowing, plots at Hamilton and Beeac that were sown to Larisa produced 3-15 times as much clover dry matter in spring as plots sown to Mount Barker. At Hamilton, the plots sown to Trikkala produced 3 times as much clover in winter as those sown to Mount Barker. This study indicates that Trikkala and Larisa offer clear advantages over the older cultivars, Mount Barker and Woogenellup, for the high rainfall areas of western Victoria, by demonstrating their persistence and long-term productivity when subjected to normal sheep-grazing practice.
Selecting for nutritive value in Digitaria milanjiana. 3. Relation of chemical composition and morphological and anatomical characteristics to the difference in digestibility of divergently selected full sibs, and comparison with D. eriantha ssp. pentzii
Authors: Masaoka Y , Wilson JR , Hacker JB
Published: March 2005

Comparisons were made of the dry matter digestibility (DMD) and yield of plant fractions harvested from long-established swards of 6 genotypes of Digitaria milanjiana selected from 3 F1 families for high and low leaf digestibility, and D. eriantha ssp. pentzii (pangola grass). Defined leaf blade, sheath and stem internode fractions were collected at different sward development stages and analysed for DMD, chemical composition, and tissue morphological and anatomical characteristics. The leaf blade of each high-digestibility genotype was consistently superior (1.9-4.5 percentage units) in DMD to that of its low digestibility counterpart, and to pangola grass, at both vegetative and reproductive -- stages. For leaf sheath and stem, the superiority in DMD of the high digestibility group was not evident or was less pronounced. The high DMD selections had green leaf dry matter yields comparable to those of the low DMD group but higher than those of pangola grass. The gain in DMD for leaf blade of the high over the low digestibility selection was consistently correlated with a decrease in cell wall content, acid detergent fibre or lignin, and poorly correlated with other chemical and leaf morphological characteristics. High and low DMD genotypes did not differ in the proportion of cell types in leaf or stem, or in other measured anatomical characteristics.
Glasshouse and field screening of chickpea cultivars for resistance to Phytophthora megasperma f.sp. medicaginis
Authors: Dale ML , Irwin JAG
Published: March 2005

The resistance expressed by a range of chickpea cultivars to phytophthora root rot in glasshouse and field trials was examined. Van der Plank's compound interest equation was the most suitable transformation for providing parameters to describe epidemic development for most of the cultivars when compared to the simple interest equation by plotting residuals and coefficients of determination. The area under the disease progress curve (AUDPC) was significantly correlated with the final disease incidence (FDI), which was also significantly correlated with the apparent infection rate (r), but r and AUDPC were not significantly correlated. The AUDPC proved to be relatively indiscriminate in this study for selecting resistant cultivars, since the value for the susceptible control cultivar was high, and many cultivars therefore had statistically lower AUDPC values. Several cultivars (i.e. CQ1591, ICC7568 and 232-4) were resistant on the basis of both the FDI and r parameters in the field trial and considered worthy of further investigation. When the parameters FDI or r were used to categorise the disease reactions of cultivars in the field, only half of the 30 cultivars assessed showed similar responses in both the glasshouse and field trials. The glasshouse assay used here does not allow the detection of all potentially useful forms of field resistance, and further work is needed in the development of a glasshouse assay which gives an accurate representation of field response to Phytophthora megasperma Drechs. f. sp. medicaginis Kuan and Erwin.
Correlation between xylem ureide levels and nodulation in field-grown Phaseolus vulgaris
Authors: Diatloff A , Redden RJ , Herridge DF
Published: March 2005

The relationships between the relative abundance of ureide-N in xylem sap and nodulation characteristics of navy beans (Phaseolus vulgaris) were examined in a sandy field site that enabled good nodule recovery. Three management treatments of N fertiliser, inoculation and no inoculation were used in the irrigated trial. Five cultivars were sown, and they were sampled 48 and 83 days later. Plant roots were scored visually for nodule size, colour, abundance and mass. Xylem sap was extracted from shoots under mild vacuum and assayed for ureide, nitrate and amino-N contents. Main treatment effects on nodulation were detected in the first but not the second sampling. Cultivar differences were found in the second sampling only. The relative abundance of ureide-N in xylem sap, measured as 100 x 4 x ureides/(4 x ureides + nitrate + amino-N), was low (<20%) in the first sampling, with no differences between cultivars. Fertiliser N depressed the ureide levels. At the second sampling, relative ureide-N ranged from 30 to 40% but there were no differences between management treatments or cultivars. Correlations between relative ureide-N and nodulation characteristics (abundance, size, colour, mass) were significant for each sampling (48 days, r = 0.29-0.33; 83 days, r = 0.72-0.76). The results indicate that it is possible to use a ureide assay as an alternative to nodule scoring where nodule recovery is impracticable in field studies of P. vulgaris.
Chemical control of bacterial canker (Pseudomonas syringae pv. syringae) of apricot and cherry in Victoria
Authors: Wimalajeewa DLS , Cahill R , Hepworth G , Schneider HG , Washbourne JW
Published: March 2005

Field trials were conducted during 1982-85, to develop a comprehensive spray program for the control of bacterial canker (Pseudomonas syringae pv, syringae) of apricot and cherry. Five spray schedules were evaluated as measures to reduce disease levels. Copper hydroxide at 2.5 g/L in water was applied to apricot, and bordeaux mixture at 6 g copper sulfate + 8 g hydrated lime/L in water was applied to cherry, during autumn, winter and pre-bloom spring. The effectiveness of copper sprays in reducing epiphytic populations of the pathogen during post-bloom spring was also tested. Copper hydroxide was applied to apricot, and a foliar copper nutrient and copper hydroxide were applied to cherry at low concentrations. Most spray schedules tested significantly (P<0.05) reduced canker incidence relative to controls. Excellent control of epiphytic populations of the pathogen on apricot and cherry was achieved with copper sprays applied at post-bloom in spring. A spray schedule consisting of 2 autumn, 1 winter and 2 pre-bloom spring sprays with copper hydroxide on apricot or bordeaux mixture on cherry was successful in reducing canker (>67% reduction) and is recommended for control of the disease. Two applications of copper hydroxide at 1.0 g/L in water in post-bloom spring considerably reduced (>9 1 %) epiphytic populations (P. syringae pv. syringae) on apricot and cherry leaves. Later sprays are recommended for use in combination with the autumn-winter-spring (pre-bloom) spray schedule, especially under excessively wet and cool weather conditions in spring.
Evaluation of a formulation of Bacillus thuringiensis against waxmoths in stored honeycombs
Authors: McKillup SC , Brown DG
Published: March 2005

Waxmoths cause significant damage to stored honeycombs of the Western honeybee Apis mellifera in Australia. A field experiment was designed to evaluate the effectiveness of a commercial formulation (Certan) of the biological control agent Bacillus thuringiensis in preventing this damage.Treatment applied at the manufacturer's recommended rate of 855 units per cm2 of honeycomb almost completely prevented damage, while untreated combs showed an average of 76% damage. The cost and practicality of applying the formulation of B. thuringiensis are discussed, together with the recommendation that new control methods for waxmoths should be researched.
Management practices and other factors contributing to the decline in persistence of grazed lucerne in temperate Australia: a review
Authors: Lodge GM
Published: March 2005

The literature relevant to the grazing management of lucerne in temperate Australia is reviewed with emphasis on the factors likely to affect its persistence. Knowledge of lucerne physiology is used to question the validity of the traditional methods of managing grazed stands, which rely mainly on using 10% flowering as a guide to root carbohydrate levels. From these data several alternative management guidelines are proposed that may lead to increased persistence; however, for long-term persistence, there is little doubt that lucerne needs to be grazed leniently and at a late stage of maturity. Several grazing experiments indicate that grazing periods of 16-20 days should have no effect on persistence, provided that the rest period between successive grazings is 35 days or longer. Data from other countries and Australian data from a limited number of experiments also indicate that grazing in either autumn or winter may substantially reduce production and could affect persistence. Three grazing studies in New South Wales were used to highlight critical differences in experimental design which make comparisons among experiments difficult. Standardised sowing rates and grazing management, and statistical procedures which account for the genotype x management x environment interaction, are suggested to improve the extrapolation of results from experiments to other environments. Persistence of different lucerne types under grazing, particularly those recently imported from the U.S.A. or bred in Australia, is considered. While it has been proposed that grazing effects may be related to crown structure, interactions with other factors which affect persistence may also occur. If grazing can be considered to be stressful to a lucerne plant then it could interact with other stresses, caused by moisture deficit, excessive moisture, insect pests and disease, to reduce persistence. Additionally, considerable variation in varietal resistance to some pests and diseases has been recorded in haycut stands, and so there may also be cultivar x grazing effects. All of these factors could combine to affect the persistence of a particular cultivar under grazing. Patterns of lucerne decline were either continuous or step-like. Continuous decline was associated with prolonged grazing, grazing and moisture stress, grazing under waterlogged conditions, or grazing in situations where the incidence of disease was likely to be high. To understand the reasons why plants fail to persist, measurements need to be made frequently and a1 regular intervals, and the moisture and disease status of the site needs to be accurately monitored. The adequacy of different methods of measuring stand persistence is also questioned. The implications for graziers, researchers and lucerne breeders are discussed.
Register of Australian Winter Cereal Cultivars: Triticum aestivum ssp. vulgare (Bread Wheat) cv. Janz
Authors: Brennan PS , Martin DJ , Eisemann RL , Mason LR , Sheppard JA , Norris RG , Smith GD , The D , Keys PJ
Published: March 2005

No abstract available.
Register of Australian Winter Cereal Cultivars: Triticum aestivum ssp. vulgare (Bread Wheat) cv. Kelalac
Authors: Martin P
Published: March 2005

No abstract available.
Register of Australian Winter Cereal Cultivars: Triticum aestivum ssp. vulgare (Bread Wheat) cv. Lark
Authors: Ballantyne BJ
Published: March 2005

No abstract available.
Register of Australian Winter Cereal Cultivars: Triticum aestivum ssp. vulgare (Bread Wheat) cv. Lillimur
Authors: O'Brien L
Published: March 2005

No abstract available.
Register of Australian Winter Cereal Cultivars: Triticum aestivum ssp. compactum (Bread Wheat) cv. Corrigin
Authors: Rosielle A , Whan B
Published: March 2005

No abstract available.
Comparison of wool production and reproductive rate of South Australian strain Merinos and locally bred Peppin Merinos in the semi-arid tropics of Queensland
Authors: Eady SJ , O'Rourke PK , Connelly PT
Published: March 2005

Three experiments were conducted to provide information on the wool production and reproductive rates of different strains of Merino sheep, and on the role of heat tolerance in determining the productivity of sheep in north-western Queensland. The locally bred Peppin Merinos had a significantly (P<0.05) lower rectal temperature (RT) and respiratory rate (RR) under heat load than the South Australian (SA) strain Merinos. Place of birth of SA Merinos had no effect on their RT and RR. At 16 months of age the Peppin sheep produced significantly (P<0.05) less clean wool (1.55 v. 1.82 kg) and had significantly (P<0.05) lower liveweights (28.5 v. 31.6 kg) than the SA group reared in the same environment. Although differences between the groups were not always statistically significant, there was a trend for a consistent increase in wool production, fibre diameter and liveweight as the proportion of SA in the cross increased. The impact of these differences on proceeds from wool sales is discussed. At maturity the SA strain ewes were heavier (P<0.05) than their Peppin counterparts (48.4 v. 44.1 kg) and produced heavier (P<0.05) lambs at 6 weeks of age (7.0 v. 6.2 kg) and at weaning (13.9 v. 12.5 kg). Milk yield at 6 weeks post-lambing was significantly (P<0.05) greater for the SA sheep than the Peppin Merinos (303 v. 216 mL/day). Lamb survival from 6 weeks to 3 months was 64% for the SA Merinos and 45% for the Peppin Merinos, but this difference was not statistically significant. The SA strain Merinos produced more clean wool and heavier offspring than locally bred Peppin sheep and demonstrated a similar reproduction rate in the face of severe drought conditions.
Effect of season and nutrition on scrotal circumference of Merino rams
Authors: Murray PJ , Rowe JB , Pethick DW
Published: March 2005

In 3 experiments, groups of 5 Merino rams were individually fed a pelleted ration at maintenance (1 kg/day), with or without 750 g/day of lupin grain, and kept indoors under conditions of natural light and temperature. Measurements of scrotal circumference and liveweight were made during winter, spring-summer and autumn, for periods of 42-49 days. Ambient temperatures and daylengths were recorded. The season of the experiment affected the rate of change of scrotal circumference. Rams fed the maintenance diet showed a pattern of increasing scrotal circumference, starting in late spring after the spring equinox and reaching a maximum in autumn-early winter, then decreasing in mid-late winter after the winter equinox. Scrota1 circumference responded to increased nutrition under all daylength regimes and the magnitude of this response was influenced by the season.
Response of vulpia [Vulpia bromoides (L.) S. F. Gray and V. myuros (L.) C. C. Gmelin] and subterranean clover to rate and time of application of simazine
Authors: Leys AR , Plater B , Lill WJ
Published: March 2005

The responses of vulpia [Vulpia bromoides (L.) S. F. Gray and V. myuros (L.) C. C. Gmelin] and subterranean clover (Trifolium subterraneum L.) to rate and time of application of simazine were compared on a red loam soil containing 1.8% organic matter and on sands containing 0.4 and 0.8% organic matter. In 1988 and 1989, applications of 0.50, 0.75 and 1.00 kg a.i./ha of simazine in late May-early June resulted in 96.4, 99.8 and 99.6% control of vulpia, respectively. Later applications in July-August, or earlier applications in April, were less effective. There were no differences in the levels of control obtained on the 2 soils, nor were there any differences in the susceptibility of V. bromoides or V. myuros to simazine. On the red loam soil simazine did not reduce subterranean clover plant density or dry matter production; however, severe reductions of both were recorded on the sandy soils. Reasons for the different responses, along with the potential for the use of simazine to control vulpia in subterranean clover pastures, are discussed in detail.
Effect of cultivars on changes in grain protein of wheat in Victoria between 1972 and 1988
Authors: Martin PJ , Eagles HA
Published: March 2005

Grain protein data from variety evaluation trials conducted in Victoria, together with proportional cultivar deliveries, were used to estimate the influence of cultivar on the average grain protein of Victorian wheat production.Soft-grained, standard height cultivars and the semidwarf Egret were all lower in protein than the hard grained cultivars which have largely replaced them. This replacement of cultivars has resulted in an average increase in protein of 0.02% per year for the period 1972-88. Any decline in average protein of the Victorian wheat crop is thus due to non-genetic factors.
Effect of soil acidity on barley production in the south-west of Western Australia. 1. The interaction between lime and nutrient application
Authors: Dolling PJ , Porter WM , Robson AD
Published: March 2005

The effect of soil acidity on barley growth in Western Australia and the role of aluminium toxicity and nutrient deficiencies were examined at 9 sites using 5 application rates of lime and 3 levels of supply of nutrients. Nutrient plant analysis was also used to assess the mechanisms involved in any response to lime.Lime application increased barley yields at 3 sites, by 9-30%, by alleviating aluminium toxicity. Nutrient treatments did not interact with the lime response. The largest reduction in grain yield (>15%) that was due to aluminium toxicity occurred at the site which had the lowest pH (4.3 in 0.01 mol CaCl2/L) and the highest concentration of CaCl2-extractable aluminium (5 �g/g).
Effect of soil acidity on barley production in the south-west of Western Australia. 2. Cereal genotypes and their response to lime
Authors: Dolling PJ , Porter WM , Robson AD
Published: March 2005

The effect of aluminium (Al) toxicity of either surface or subsurface soil on the growth of barley, and the potential for variation in response to soil acidity among agronomically adapted Australian barley genotypes, were examined at 13 sites. The effect of Al toxicity was investigated by plant analysis, using 3-5 lime application rates and Al-tolerant species (wheat, triticale), as well as barley. All cereals were supplied with complete nutrients. To measure the potential for response variation, grain yields of 14 genotypes of barley, relative to cv. Stirling, were related to soil pH at 7 sites. Grain yield of barley was increased 9-30% at 6 sites, by lime application alleviating A1 toxicity. The yield of triticale and wheat cv. Aroona was not increased by lime application at any site. There was some indication that subsurface acidity may be reducing the grain yield of barley at sites with CaCl2-extractable Al concentrations of 23-4 mg/g in the A2 horizon. Some barley genotypes appeared to be more tolerant than Stirling to soil acidity. Aluminium toxicity appears to be reducing barley grain yields by more than 10% at surface soil pH <4.5 (0.01 mol CaCl2/L), or when CaCl2-extractable Al is >3-4 mg/g. CaCl2-extractable A1 in the surface soil was not a better indicator of Al toxicity than soil pH.
Effect of saline water on rice yields and soil properties in the Murrumbidgee Valley
Authors: Beecher HG
Published: March 2005

Rice was grown on a transitional redbrown earth for 3 consecutive seasons and irrigated with saline groundwater of salinities 0.25, 0.5, 1.0, 1.5 and 2.0 dS/m. A 4.0 dS/m treatment was applied in the final year. Grain yield was only affected by the 4.0 dS/m treatment, where a 25% yield reduction occurred. Soil salinities increased with increasing salinity of applied treatments, reaching equilibrium after 3 years. The higher salinity treatments resulted in significantly increased rice field water consumption, attributed to increased infiltration rates. The presence of high electrolyte levels in the soil surface prevented any detrimental effect of increased soil sodium levels on soil properties. However, the communal supply system with potential cultivation of salt-sensitive species such as soybean, along with the potential for higher groundwater accessions, suggests that the salinity of irrigation water should be maintained as low as possible.
Effectiveness of zinc sulfate and zinc chelate as foliar sprays in alleviating zinc deficiency of wheat grown on zinc-deficient soils in Western Australia
Authors: Brennan RF
Published: March 2005

The relative effectiveness of zinc chelate (Zn-EDTA, 15% Zn) and zinc sulfate (23% Zn) applied as f o l k sprays for alleviating zinc deficiency of wheat was assessed. The experiments were conducted at 3 sites in 3 different years, in the Newdegate district about 350 km south-east of Perth, Western Australia. Each source was sprayed at 6 rates of Zn, to define the relationship between grain yield and the amount of foliar Zn applied for wheat grown on Zn-deficient soils where no Zn had been previously applied. The levels of Zn sprayed were 0, 25, 50, 100,200 and 400 g/ha (experiment 1); and 0, 28, 56, 112, 225 and 450 g/ha (experiments 2 and 3). Foliar-applied zinc chelate was 1.4-1.7 times more effective than zinc sulfate applied at the GS 14 growth stage. However, the sprays were equally effective when applied at the GS 23-24 growth stage. Zinc sulfate banded with the seed at sowing produced the highest grain yields.
Variability in cut flower production of Banksia coccinea R.Br. and Banksia menziesii R.Br. at six locations in southern Australia
Authors: Fuss AM , Sedgley M
Published: March 2005

Cut flower production from seedling plants of Banksia coccinea and B. menziesii was investigated on 6 commercial plantations in southern Australia (3 in each of South Australia and Western Australia). Both species exhibited variability in the total number of blooms produced per plant, bloom quality, stem and inflorescence length of the harvested bloom, and the time of production within the flowering season. Production of B. coccinea in South Australia extended from July to October, with most blooms harvested in September. Blooms on B. menziesii were produced over an 8-month period from March to October, with peak production in March-April. Each species showed some abnormal floret development. There were significant (P<0.001) between-site differences in B. coccinea for the number of blooms produced and the proportion which were abnormal. Maximum production (average 75.3 blooms per bush) was recorded near Albany, Western Australia, close to the natural habitat of B. coccinea. In comparison, few blooms (average 3.2 per bush) were produced at Muchea, Western Australia.
An evaluation of the production potential of six tropical grasses under grazing. 2. Assessment of quality using variable stocking rates
Authors: Evans TR , Hacker JB
Published: March 2005

The potential quality of the 6 pasture grasses Setaria sphacelata var. sericea cvv. Nandi, Kazungula and Narok and var. splendida, Digitaria eriantha ssp. pentzii (pangola grass), and Pennisetum clandestinum cv. Whittet (kikuyu grass) was assessed in terms of liveweight gain of beef cattle, using a leader and follower grazing system. Pasture management was designed to provide adequate quantities of young leaf to the leaders throughout the year. This was achieved by rotational grazing and weekly adjustment of the number of followers, depending on quantity of feed available. Annual liveweight gain of the leaders (kg/steer.year) ranged from 135 (kikuyu grass) to 159 (cv. Narok) (540-636 kg/ha.year). Differences between grasses on an annual basis and over summer were not statistically significant (P = 0.12), although significant differences in liveweight gain of leaders - - - were obtained during the winter. This was associated with differences between grasses in growth at lower temperatures, and in frost tolerance. Liveweight gain of the follower group was markedly higher for pangola grass and var. splendida (272 kg/ha.year) than for the other varieties (77-140 kg/ha.year). This difference was associated with differences in number of grazing days and in the superior liveweight gain per head of followers grazing pangola grass and splendida. Liveweight gain of leaders per annum was comparable for years 1 and 2 but fell dramatically from February to August in year 3. This was associated with high rainfall, reduced solar radiation, and a decrease in in vitro digestibility of plucked leaf of all setaria varieties but not of pangola or kikuyu grasses. The relatively low liveweight gains obtained in year 3 were not associated with any overall mineral or protein deficiency.
Variation in flowering times and agronomic characteristics of Medicago laciniata (L.) Miller collected from diverse locations in New South Wales
Authors: Young RR , Croft PH , Sandral GA
Published: March 2005

Thirty-two accessions of Medicago laciniata (L.) Miller collected from throughout western New South Wales and 1 from southern Queensland, 4 accessions of M. minima (L.) Bartalini, 1 of M. polymorpha L., and 3 cultivars of M. truncatula Gaertner were grown in rows at Condobolin over 2 years. There were no significant differences between the M. laciniata accessions for flowering time, dry matter score, seed yield, pod weight, and seed weight in either year. No differences were detected in plant or pod morphology. This lack of variation means that any accession may be used as parent material for a breeding program to reduce pod spine and potential to contaminate wool. Should absence of phenotypic variation be indicative of no genotypic difference, it follows that all the M. laciniata accessions had a common origin.
The influence of crossing strategy on the potential for breeding new crop varieties
Authors: Brennan PS , Butler DG
Published: March 2005

Crosses between commercially acceptable varieties and introductions are most likely to generate segregation at many loci of commercial importance. The probability of recovery, after selfing, of individuals in which most of the favourable alleles have been accumulated is very low. Reducing the number of favourable alleles heterozygous in the breeding population would increase the probability of success. The utility of a single backcross (BC1) to the parent with the greatest number of favourable alleles was examined as a method of fixing commercially desirable alleles. The means for stability parameters for yield for BC1F2-derived populations were similar to those for F2-derived populations. The genetic variance for yield in 2 of the 3 crosses studied was greater for the BC1F2- than the F2-derived populations, while the genotype x environment interactions appeared to be smaller for the BC1F2 populations. This suggested that BC1F2-derived populations may be more productive, in terms of varietal production, than F2-derived populations, particularly in species with a long breeding history and/or a large number of desirable characteristics.
Effects of hydrogen cyanamide, paclobutrazol and pruning date on dormancy release of the low chill peach cultivar Flordaprince in subtropical Australia
Authors: George AP , Lloyd J , Nissen RJ
Published: March 2005

The growth regulator hydrogen cyanamide (Dormex, 50% a.i.) was tested for its effectiveness in promoting earlier and more even budbreak, flowering, and fruit maturity of the low chill peach cv. Flordaprince at 2 sites in subtropical Australia. The influence of the growth retardant paclobutrazol was also tested at 1 site, and at the other, the effect of altering pruning date. At 1 site only, hydrogen cyanamide applied early-mid June, during endodormancy, advanced mean harvest time by 10 days. At the other site, there were no consistent trends between harvest time and date of application of cyanamide. Dormex at the lowest concentration applied (10 mL/L) caused severe yield reductions (40.8%). Flowering and fruit maturity were advanced by about 6 days with dormant pruning in early winter, compared with pruning at later dates, and by 13 days with the application of the growth retardant paclobutrazol, compared with no application.
Evaluation of paclobutrazol on growth, flowering and yield of mango cv. Kensington Pride
Authors: Winston EC
Published: March 2005

The growth retardant paclobutrazol was applied after harvest as a foliar spray, a band along the drip line, or a collar drench in trials over 3 years on 3-, 4-, and 5-year-old trees of mango cv. Kensington Pride. The trees were assessed for percentage of branches with vegetative flush, flush length, flowering, and yield. Paclobutrazol reduced length of vegetative growth in all trials. Eight mL a.i. per tree, applied as a single yearly collar drench, significantly (P<0.05) reduced percentage flush. Collar treatments were significantly (P<0.05) more effective than drip line treatment in reducing length of vegetative growth. Two years' collar drench was generally more effective than a band treatment followed by a collar drench. In particular, collar drenches of 4 and 8 mL a.i./tree, applied for 2 consecutive years, reduced summer growth. Flowering and cropping were significantly (P<0.05) increased by paclobutrazol in a year of inadequate winter stress, while a trend towards increased yield was noted under more normal conditions. Yield increases were due to fruit numbers rather than size. Fruit colour was unaffected. Soil-applied treatments were more effective on flowering and cropping than foliar treatment, with collar drenches more effective than drip line treatment. A trend for decreasing yields was found when paclobutrazol was applied as a collar drench for 2 consecutive years at the same rate, compared with an ineffective drip line followed by a single collar treatment. Rates of paclobutrazol >4 mL a.i./tree caused unacceptable compaction of flower panicles. Four mL a.i./tree appeared the best application rate given the prevailing soil type, climatic conditions, and tree size and age.
Flowering and fruit set in lychee (Litchi chinensis Sonn.) in subtropical Queensland
Authors: Menzel CM , Simpson DR
Published: March 2005

The pattern of panicle and flower development of lychee (Litchi chinensis Sonn.) trees was studied in subtropical Queensland (lat. 27�S.). The cultivars studied were Tai So at 3 sites, Bengal at 4 sites, Kwai May Pink at 2 sites, Salathiel at 3 sites, and Wai Chee at 2 sites. Tai So was the earliest cultivar, with panicle emergence in late May and flower anthesis in mid September. The other cultivars were 5-7 weeks later. Tai So had a longer period of flower anthesis than the other cultivars (4 weeks v. 1-3 weeks). Cultivars Tai So and Bengal generally had longer panicles than cvv. Kwai May Pink, Salathiel and Wai Chee (17-32 v. 10-14 cm), and more flowers per panicle (1800-3400 v. 400-900). Similarly, the number of fruit per panicle ranged from 7-33/panicle 2-3 weeks after the end of flowering, to 4-22/panicle at harvest. The proportion of female flowers setting fruit ranged from 2.1 to 19.5%. Similar estimates for fruit carried to harvest ranged from 0.8 to 6.8%. Variations in the times of panicle emergence, panicle development, and anthesis among the cultivars in relation to seasonal progressions in temperature affected the number of fruit set. The number of fruit set per panicle increased as the number of female flowers per panicle increased. Higher numbers of female flowers were associated with maximum temperatures during flower development of 18�C, with lower numbers at 23�C. Higher maximum temperatures during anthesis (30�C v. 24�C) increased the proportion of female flowers setting fruit.
Response of potatoes (Solanum tuberosum cv. Russet Burbank) to band-placed and broadcast high cadmium phosphorus fertiliser on heavily cropped krasnozems in north-western Tasmania
Authors: Sparrow LA , Chapman KSR , Parsley D , Hardman PR , Cullen B
Published: March 2005

Four field experiments were conducted to examine the yield response and cadmium (Cd) concentration of potatoes (Solanum tuberosum L. cv. Russet Burbank) grown with banded or broadcast phosphorus (P) fertiliser at rates up to 240 kg P/ha. The Cd content of the triple superphosphate (TSP) was 151 mg/kg. All 4 sites were on intensively cropped, high P-fixing krasnozem soils in north-western Tasmania, with concentrations of Colwell-extractable P ranging from 112 to 210 mg/kg. All sites showed economic yield responses to banded P, but broadcast P was much less effective except at the site where the response to banded P was least. Yield responses came mostly through increased tuber number, but at 1 site the tubers were also bigger. There was no effect of P on tuber size distribution or specific gravity. Increasing rates of banded TSP increased tuber Cd concentrations by 50-300% at the 3 sites where they were measured; broadcast TSP had little effect. Tubers from the site with pH 6.0 had much higher Cd concentrations than those from the sites with pH 6.5 and 6.6. Petiole Cd concentrations were about 5 times greater than tuber concentrations.
Effect of bunch-covering methods on maturity bronzing, yield, and fruit quality of bananas in North Queensland
Authors: Daniells JW , Lisle AT , O'Farrell PJ
Published: March 2005

The timing of bunch covering during the development of bananas was examined to find the optimum for fruit quality and reduction of maturity bronzing. Bunch covers, either open or sealed, were applied at various stages of bunch development. The experiments were carried out at South Johnstone, North Queensland. Sealed covers increased the severity of maturity bronzing whenever they were applied. Sealed covers applied for the period either before or after finger diameter of the third hand had reached 2.7 cm increased maturity bronzing, but not by as much as when covers remained sealed throughout bunch filling. These data indicate that sealed covers increase maturity bronzing throughout fruit growth. Maturity bronzing was slightly less when open covers were applied as the last female bract lifted on the bunch (early), compared with a week or so later when the fingers had curled up. Bunch weight was not increased by the application of open covers, but the use of sealed covers increased bunch weight by up to 9%. This was due to increased finger length along the entire bunch. The application of covers (both open and sealed) at earlier than conventional times increased finger length at the proximal end of the bunch, the effect being greater the earlier covers were applied. Open covers reduced the time taken from bunch emergence to harvest by 5-11 days compared with no covering. Very early and early covering gave the largest reductions. Sealed bunch covers delayed harvest by up to 16 days compared with no covering. There was a non-significant reduction of 2-4 days in fruit greenlife, related to the delay in bunch filling caused by sealed covers. Sealed covers led to some fruit abnormalities, including severe spotting by Deightoniella sp., slightly s-shaped fruit, and dull fruit appearance. Early application of open bunch covers is recommended to reduce maturity bronzing. This treatment also increases finger length, and bunch filling time is reduced by about 1.5 weeks. This effect suggests sensitivity to the environment during and soon after bunch emergence.
Phosphonic acid controls downy mildew (Peronospora parasitica) in cauliflower curds
Authors: McKay AG , Floyd RM , Boyd CJ
Published: March 2005

Postharvest development of downy mildew (Peronospora parasitica) symptoms in export cauliflower curds has resulted in economic losses to growers in south-western Australia. Neutralised phosphonic acid sprays applied onto cauliflowers in the field within 3 weeks of harvest reduced this disease. Two applications of 2.4 kg a.i./ha, 21 and 7 days before harvest, reduced the incidence of curds affected by downy mildew from 92% in untreated plots to 8%. The maximum phosphonate residue in curds at harvest was 12 �g/g, while control curds contained no detectable phosphonate. No effects of phosphonic acid on crop appearance or maturity were observed, and while a small (8%) reduction in curd weight was significant (P = 0.039), there was no yield trend with increasing phosphonic acid rate.
Plant population studies on peanut (Arachis hypogaea L.) in subtropical Australia. 2. Water-limited conditions
Authors: Wright GC , Bell MJ
Published: March 2005

The effects of plant population density on total dry matter (TDM) production, and on pod and kernel yields, of 2 peanut (Arachis hypogaea L.) cultivars (Virginia and Spanish) were investigated under a range of contrasting soil water availability regimes. Protracted crop water deficits were applied to each plant population density treatment in 3 experiments: (i) from planting until the early pod-filling phase (DSWF, dry start, wet finish); (ii) during the pod-filling to maturity phase (WSDF, wet start, dry finish); (iii) from flowering to maturity (TS, terminal stress). Crop water deficits of varying timing and severity were shown to modify substantially the effect of plant population on yield response compared with that observed under well-watered conditions. In most cases, TDM was maximised at the lowest density (40000 Plants/ha). In the WSDF and DSWF experiments, significant cultivar x plant population interactions for pod yield were found. The Spanish cultivar, McCubbin, showed strong pod yield response to S30000 plants/ha, while the Virginia cultivar, Early Bunch, did not respond to increases in plant population above 40000 plants/ha. These differing responses were probably associated with cultivar differences in branching pattern. Under extreme water stress situations where crops were forced to rely solely on soil water reserves (TS), pod yields were highest at the lowest plant population density and declined rapidly as plant population increased. The Gardner and Gardner (1983) model provided a useful framework to characterise the plant population-pod yield response under reduced water availability. The assumptions that both partitioning of dry matter to pods and the hypothetical minimum plant size capable of producing pods were crop constants, irrespective of crop water deficits experienced, were shown to be invalid. These constants may, however, be linearly related to water availability. Relationships relating these parameters to an index of crop or soil water status may improve the predictive capability of the model under water-limited conditions.
Effect of nitrogen and potassium on growth and yield of coffee (Coffea arabica L.) in tropical Queensland
Authors: Winston EC , Littlemore J , Scudamore-Smith P , O'Farrell PJ , Wiffen D , Doogan VJ
Published: March 2005

The effects of nitrogen (N) and potassium (K) on coffee (Coffea arabica L.) growth and yield in a shallow sandy soil in North Queensland were studied over 5 years following field establishment. High rates of N (416 and 624 kg/ha) applied frequently were necessary for rapid growth and yield of cvv. Kairi Typica (K2), Caturra Rojo (CR33), Catuai Rojo (CR35), and Bourbon Red (B61). Although data were not significant, mean yields with 416 and 624 kg N/ha were greater than with 208 kg/ha by 124 and 145% in 1986, by 12 and 26% in 1987, and by 38 and 31% in 1988. Increasing rates of K (63, 126 and 189 kg K/ha) did not affect growth and did not significantly increase yield in the later stages of the experiment. Neither N nor K had any affect on green bean size or time of berry maturity. CR35 was the highest yielding cultivar (3752 kg/ha of green bean in 4 years of cropping) and B61 the lowest (2067 kg/ha). Height and girth were ranked K2 > CR35 > CR33 > B61. B61 also had significantly fewer and shorter longest primary laterals. CR35 ripened later than other cultivars, while B61 produced the highest percentage of large beans, and K2 the highest percentage of small beans. Preliminary recommendations for coffee growers in this region are 100 kg N/ha in year 1, increasing to 400 kg/ha in year 4; and 80 kg K/ha in year 1, increasing to 320 kg K/ha in year 4. Monthly, rather than quarterly, applications are recommended.
Postharvest quarantine disinfestation of zucchinis and rockmelons against Bactrocera cucumis (French) using insecticide dips of fenthion or dimethoate
Authors: Heather NW , Walpole DE , Corcoran RJ , Hargreaves PA , Jordan RA
Published: March 2005

The disinfestation efficacy of a 1-min dip in fenthion or dimethoate (400 mg/L in water) was tested against eggs and larvae of the cucumber fly, Bactrocera cucumis, in zucchinis and rockmelons. Each trial involved >30 000 individuals. Fenthion gave 100% mortality of eggs and third instar instar larvae in rockmelons, 100% mortality of eggs in zucchinis, and >99.99% mortality of third instar larvae in zucchinis. Dimethoate gave 100% mortality of eggs in zucchinis, >99.98% mortality of third instar larvae in zucchinis, and >99.99% mortality of eggs and larvae in rockmelons. Residues of fenthion and dimethoate in zucchinis or rockmelons were below the Australian maximum residue limit of 2 mg/kg on the day of treatment. There were no adverse effects on taste.