bluuebunny/crossref_metadata_2025 huggingface dataset:
Low pasture productivity of a sedimentary soil in relation to phosphate and water supply
Authors: Cornish PS , Myers LF
Published: March 2005

Reasons for the low pasture production of a soil derived from Ordovician sediments in the Yass Valley 50 km north of Canberra were investigated in field and glasshouse experiments. In the field, at a moderate phosphate level, application of water to the soil surface in the autumn increased yields although rainfall was above average and soil water was adequate for growth. At a high phosphate level there was no response to this surface wetting. In this soil, available phosphate (Truog) was confined to the 0-5 cm layer. In the glasshouse surface wetting increased yield and phosphorous uptake even though soil water was maintained at adequate levels below the immediate surface. Placement of phosphate at 8 cm depth where the soil remained wet for a longer time led to substantial yield increases over surface applied phosphate. In the field, a productive soil nearby derived from porphyry rock did not respond to surface wetting and yields were higher than those on the sedimentary soil. In the following moist spring, yields on the sedimentary soil were slightly better (P < 0.01) than yields on the porphyry soil. Available evidence suggests that surface drying limits the uptake of surface applied phosphate on the sedimentary soil. Thus phosphate levels that would be adequate for growth are inadequate in the early autumn when evaporation from the soil surface is greatest. On the adjacent porphyry soil, surface applications were fully effective.
The role of fungi and nematodes as factors associated with death of white clover (Trifolium repens) stolons over summer in south-eastern Queensland
Authors: Irwin JAG , Jones RM
Published: March 2005

A series of laboratory and field trials examined the role of both fungi and nematodes in causing stolon death of white clover (Trifolium repens) which is typically encountered over summer/early autumn in sub-tropical coastal Queensland. Pythium middletonii was consistently isolated from necrotic stolons and roots of Trifolium spp. collected at a range of sites, and was the only fungal species isolated that was pathogenic to white clover seedlings in glasshouse tests. Under controlled environment conditions P. middletonii also caused a root and stolon rot of mature plants similar to that observed in the field. Preliminary studies suggested that some naturalized white clover strains are more resistant as seedlings than commercial white clover cultivars. In 1974-75 and 1975-76 fungicides were applied at monthly intervals over summer to grazed pastures at two sites. Stolon death was significantly reduced by fungicide at one site in one year. The possible role of plant parasitic nematodes in the decline syndrome was investigated in 1975 at three sites: the decline in clover was significantly reduced by nematicide at each site.
Summer dormancy, regeneration and persistence of perennial grasses in south-western Australia
Authors: Biddiscombe EF , Rogers AL , Maller RA
Published: March 2005

Autumn growth and persistence of periodically grazed, spaced plant swards of eleven perennial grasses were measured at two sites registering 750 mm and 1120 mm annual rainfall respectively. The grasses were grown on gravelly podzolic soils of moderate internal drainage and depth of A horizon. After the third summer, autumn regrowth was generally better in Phalaris tuberosa lines than in lines of Dactylis glomerata, Festuca arundinacea and Lolium perenne, Festuca arundinacea cv. Melik and D. glomerata cv. Currie regenerated better than P. tuberosa lines in the first two autumn seasons at the drier site. Capacity for autumn growth appeared to be associated mainly with the level of dormancy achieved by basal buds at mid-summer, though relatively high dormancy of one or two lines at the drier site did not prevent significant plant mortality. Numbers of reproductive tillers per plant in spring and active basal buds per tiller in late summer were less important traits affecting the growth of some lines. We think that rankings for summer dormancy would be useful for screening future introductions for wetter parts (> 750 mm annual rainfall) of the south-western region of Western Australia.
Developmental responses of different hexaploid triticales to temperature and photoperiod
Authors: Brouwer JB
Published: March 2005

The developmental responses to temperature and photoperiod of five hexaploid triticales (X Triticosecale Wittmack) of diverse origin (T64, SPA 69, UM3, Badger, 6TA419) and one wheat cultivar (Olympic) were examined in the field at Werribee, Victoria in 1974. Six times of sowing and the use of supplemental illumination, providing an 18 hour daylength at one of the two sites, created a range of different photoperiod and temperature treatments. The durations of the following phases were taken as the responses to phtoperiod and/or temperature: emergence to ear initiation (El), ear initiation to heading (IH) and anthesis to maturity (AM). The data from the natural and the 18 hour photoperiod regimes were analysed separately by stepwise regression analysis. The introduction of pseudovariables made it possible to study varietal effects. The order in which the varieties reached the various developmental stages changed very little with the successive times of sowing, but differed when the natural daylength was compared with the 18 hour regime. The responses of the triticales to temperature and photoperiod were quantitative. The duration of each phase was shortened by a longer mean daily photoperiod or a higher mean daily temperature, the photoperiod having a greater effect than the temperature. Large varietal differences caused low coefficients of determination of the El phase under natural and 18 hour photoperiod (43.9 and 6.4 respectively), when regression equations were fitted, which were common to all varieties. The values were higher for the IH phase (64.6 and 68.6 respectively), The introduction of the pseudovariables in the analysis resulted in equations accounting for 85.0-96.7 per cent of the variation in both phases under 18 hours or natural daylength. The varietal effect on the duration of the AM phase was small. The coefficients of determination of the regression equations for this phase under both the 18 hour and the natural photoperiodic regime ranged from 88.7 to 94.9. The response of the triticales to a vernalization treatment was small, indicating that vernalizing the seedlings prior to planting would not have greatly improved the predictive value of the regression equations.
Chemical weed control in oil-seed poppy (Papaver somniferum)
Authors: Baldwin BJ
Published: March 2005

Field experiments were conducted in north-west Tasmania to assess the herbicides diquat and nitrofen, used singly and in combination, for selective post-emergence weed control in oil-seed poppies (Papaver somniferum). The species of weeds infesting the crop influenced yield responses to the herbicides. In the absence of fat hen (Chenopodium album) and fumitory (Fumaria muralis), crop production increased linearly with rate of diquat. The highest rate of diquat (280 g ha-1) produced a yield that was not significantly different (P = 0.05) from the hand-weeded control. In the presence of these two weeds, linear yield responses to rates of both diquat and nitrofen were obtained. There was no significant interaction effect on crop yields between these two herbicides, but a mixture of both chemicals was required for effective weed control. The tolerance of the crop to the herbicides was measured in the absence of weed competition. No effects on crop yields were obtained, although some treatments retarded the growth of the crop and caused a significant (P = 0.05) reduction in the height of the crop at flowering.
A cone penetrometer for estimating available soil water
Authors: Fawcett RG
Published: March 2005

The effect of cone diameter (9.5 to 24.4 mm; 9.5 mm shaft) on the entry of penetrometers into swelling clay soils, and the relations between penetration and soil water contents, have been studied in northern New South Wales. Cones with diameters of approx. 14 mm were chosen for calibration tests on farms. The depth of wet soil and the amount of available water within the wetted zone were both related to the depth of maximum cone penetration (r2 values of 0.78-0.98 at sites with relatively uniform profiles of soil texture). Available soil water contents and water potentials were also related to the force needed for cone penetration. The penetrometer will assist in estimating soil water contents in areas where grain yields are related to available fallow water at seeding.
Nutritional status of stone fruit orchards in the Swan Hill district, Victoria
Authors: Taylor JA
Published: March 2005

Diagnostic leaf analysis was used to assess the nutritional status of 22 stone fruit orchards in the horticultural areas near Swan Hill, Victoria. Leaf sampling was continued over the three years 1973, 1974 and 1975 and included apricot, plum, nectarine, cherry and peach trees. Low N and Fe were common to most varieties, very low Zn levels were widespread, Mg tended to be high and low P was characteristic of nectarines and peaches.
Soil application of elemental sulphur as a control of Phytophthora cinnamomi root and heart rot of pineapple
Authors: Pegg KG
Published: March 2005

Preplant soil applications of elemental sulphur controlled root and heart rot of pineapple (Ananas comosus) caused by Phytophthora cinnamomi. A pH value below 3.8, which is required to limit the activity of P. cinnamomi, did not adversely affect vegetative growth of pineapple plants. Leaf calcium levels fell in sulphured soils, and natural flowering was inhibited. An application rate of 1200 kg ha-1 elemental sulphur has been recommended for soils with low buffering capacity. Aluminium sulphate and ammonium sulphate were not as effective as sulphur, possibly because they did not reduce soil pH below 3.8. Dolomitic limestone did not affect disease incidence. In one experiment the fungicides captafol and ethazol were as effective as sulphur. Covering pineapple beds with black polythene sheeting increased root and heart rot.
Stocking rate, joining time, fodder conservation and productivity of Merino ewes. 2. Birth weight, survival and growth of lambs
Authors: Egan JK , Thompson RL , McIntyre JS
Published: March 2005

In an experiment at Hamilton in western Victoria, groups of 30 Merino ewes were stocked at 11.7, 15.4 or 19.2 ewes ha-1 and joined to Merino rams each year on April 5 or May 8 for five weeks. Hay was conserved on half the number of plots and fed back to the ewes before and during joining. Observations on birth weight, survival, and growth of lambs born between 1970-73 are presented. Both the highest stocking rate and the earlier lambing were associated with a depression of about 7 per cent in the birth weight of twin lambs, but single lambs had similar birth weights on all treatments. Lamb survival was highly variable and there were few significant treatment effects. However, mortalities within 48 hours of birth were lower amongst flocks joined to lamb in October than those lambing in September (single lambs 9.2 per cent vs. 14.7 per cent-twin lambs 19.9 per cent vs. 40.2 per cent). Most of the improvement was attributed to drier conditions and lower windspeeds in October. Lamb growth rates fell with increasing stocking rate but the variation in weaning weight was less than 2 kg. Lambs born in September were about 10 per cent heavier at weaning than those born in October. Compensatory growth after weaning resulted in negligible differences in weight at 12 months between lambs from the different stocking rate treatments, but lambs born in September were still significantly heavier than those born in October.
Influence of high calcium rearing diets, Christmas Island phosphate and ethylenediamine-tetraacetic acid on the laying performance of White Leghorn × Australorp hens
Authors: Karunajeewa H
Published: March 2005

White Leghorn x Australorp pullets were reared on diets with either low (0.91-1.12 per cent) or high (1.45-1.93 per cent) levels of calcium; in the laying phase pullets from each rearing regime were fed diets with either sterilized bone meal or Christmas Island phosphate as sources of supplemental phosphorus. Each of these layer diets was supplemented with 0, 300 or 500 p.p.m. of EDTA. The level of calcium in the rearing diets had no significant effect on liveweight, feed intake or mortality of the pullets during either the rearing or laying phases. High calcium starter and grower diets, however, reduced rate of lay by 2.1 per cent (P < 0.05) and efficiency of feed conversion by 3.7 per cent (P < 0.01). There was also a non-significant tendency to lower shell thickness. The inclusion of 2.5 per cent Christmas Island phosphate in the laying diet, resulting in a daily intake of 46 mg of fluorine per hen, decreased rate of lay by 2.2 per cent (P < 0.05), hen-housed egg production by 11 eggs (P < 0.05) and efficiency of feed conversion by 5.0 per cent (P < 0.01). The addition of 300 p.p.m. EDTA to the laying diet significantly (P < 0.01) improved efficiency of feed conversion by 4.7 per cent. Neither the source of phosphorus nor the dietary level of EDTA had any significant effects on liveweight, egg weight, feed intake, shell quality or mortality.
Hybrid pennisetum in a warm temperate climate: productivity span and effects of nitrogen fertilizer and irrigation on summer production and survival
Authors: Muldoon DK , Pearson CJ
Published: March 2005

Changes in dry matter yield and its components and plant survival were examined in hybrid pennisetum under different rates of nitrogen fertilization on irrigated and dryland areas throughout two growing seasons. The productivity of first, second and third year stands was studied. Production was markedly seasonal; almost half of the maximum annual yield of 11.4 t ha-1 came from six weeks regrowth in mid-summer. Summer production was restricted by drought and in 1975-76 by low temperatures and radiation. There was interaction between environmental conditions and responses to N. When conditions were favourable the dry weight and leaf area responses were linear. Under moisture stress, or low temperatures and radiation, plants responded only to intermediate levels of N because of suppressed leaf and tiller production. Protein concentration increased with N. Protein and digestibility were adequate for animal production except in mid-summer, when rapid plant development under irrigation and high N resulted in digestibility values of less than 60 per cent. Survival was high except when plants were cut just prior to winter, i.e. in April, or high rates of N fertilizer were applied. Production increased in the second year because of tiller multiplication; individual tiller weights decreased. Productivity was maintained into the third year.
Growth and quality of tropical forages in a temperate climate
Authors: Pearson CJ , Dawbin KW , Muldoon DK , Campbell LC
Published: March 2005

Dry matter accumulation in maize, hybrid pennisetum and mid- and late-season pearl millet were assessed following planting in mid-summer at Camden, New South Wales. Productivity was high in maize and hybrid pennisetum, the maximum above-ground rate of dry matter accumulation averaging 590 kg ha-1 day-1 for 20 days for maize in March 1975. Productivity was lower in the pearl millets which lodged in April of 1975 and 1976. Organic matter digestibility was superior in maize, phosphorus concentrations were higher in hybrid pennisetum and magnesium and calcium concentrations were the same in hybrid pennisetum as in maize. The concentrations of minerals would be generally too low to maintain highly-productive livestock if they were fed exclusively on these tropical forages.
Survey of snails on citrus in the Riverland of South Australia
Authors: Furness GO
Published: March 2005

A survey of snails and snail damage to 95 blocks of citrus in the Riverland of South Australia was made during 1974 and 1975. The owners of each block were interviewed to determine the cultural practices used and to find out if control measures were applied. An examination of the orchard was made to determine the amount of snail damage to the crop and the species of snails present. The European brown snail Helix aspersa (Muller) was the only species causing significant damage. Snail damage was most severe on orchards irrigated by overhead sprinklers, less severe where undertree sprinklers were used, and rarely a problem on furrow irrigated orchards (P < 0.01). Cultivation did not significantly affect the snail problem. In 1974 an estimated 43 per cent of orchards either had more than 10 per cent crop damage or were sprayed to control snails. In 1975 there were an estimated 9 per cent of orchards affected to that extent.
The role of seed infection in the spread of blackleg of rape in Western Australia
Authors: Wood PMcR , Barbetti MJ
Published: March 2005

A survey of rapeseed crops in Western Australia for blackleg (Leptosphaeria maculans (Desm.) Ces and de Not) infection was conducted in November 1972. No correlation between levels of pod infection in November and seed infection at maturity was established. An in vitro test showed that 67 per cent of L. maculans infected seeds gave rise to seedlings with one or both cotyledons infected. Under field conditions in 1974, a plot grown from 5.9 per cent infected seed resulted in 19.0 per cent of plants developing blackleg crown cankers, whereas a plot containing 0.08 per cent infected seed gave 1.1 per cent of plants infected. The following year at a different location, a sample assessed at 0.5 per cent infection produced only 0.06 per cent of plants with crown cankers, and, 0.08 per cent infected seed yielded 0.08 per cent infected plants.
Milk production, milk composition, rate of milking and grazing behaviour of dairy cows grazing two tropical grass pastures under a leader and follower system
Authors: Stobbs TH
Published: March 2005

Milk production, milk composition, rate of milking and grazing behaviour were measured for lactating Jersey cows having both the first opportunity to graze (leaders) and also when offered the remaining herbage (followers) from 3-week regrowths of two nitrogen-fertilized tropical pastures, Rhodes grass (Choris gayana cv. Pioneer) and Gatton panic (Panicum maximum cv. Gatton). Twenty-four cows were used in a latin-square design with experimental periods of 14 days. Both leaders and followers were allocated 40 kg DM cow-1 day-1. Leader cows produced 8.0 kg milk cow-1 day-1 compared with 5.8 kg milk cow-1 day-1 for followers, a difference of 38 per cent. Both leader and follower cows grazing Gatton panic produced more milk than cows grazing Rhodes grass. Milk from leader cows contained a higher percentage of solids-not-fat and protein and a lower butterfat percentage indicating a higher intake of digestible nutrients. Cows showed a preference for leaf, and after easily accessible leaf was removed by leader cows the follower cows had a small bite size. Follower cows partially compensated by increasing grazing time, mainly at night. Follower cows had a longer let-down time and a longer milking time per kilogram of milk produced. Milk production was linearly related to bite size and availability and accessibility of leaf were considered to be the main factors influencing production.
The performance of pregnant and lactating Merino ewes and their lambs fed survival rations of wheat grain and sawdust
Authors: Hunter RA
Published: March 2005

Merino ewes were mated at pasture and then fed in pens either a maintenance or an 80 per cent maintenance ration of wheat grain three times a week. Half the animals at each feeding level were offered Spotted Gum (Eucalyptus maculata) sawdust. Addition of sawdust to the ration did not affect liveweight change and the wool growth rate of ewes or the birth weight and growth rate of lambs. It did, however, affect the long-term survival rate of ewes. Of the ewes that died after three months of survival feeding, four were in groups fed wheat alone and one in a group fed sawdust with the wheat. The survival rate and growth rate of lambs in all treatments were poor.
Effects on wool production during pregnancy and lactation of twice daily abomasal supplementation with casein or methionine and cystine
Authors: Williams AJ , Tyrrell RN , Gilmour AR
Published: March 2005

The responses in wool production of Merino ewes to abomasal supplements of casein (56 g day-1) and of a mixture of methionine and cystine were measured during late pregnancy and early lactation. The mixed supplement provided equal quantities of the sulphur amino acids as the casein. The ewes were offered sufficient quantities of a diet of sorghum grain/lucerne hay (in the ratio 7 : 3 by weight) to maintain maternal liveweight. During the final four weeks of pregnancy and the first six weeks of lactation, the cassin supplement increased wool growth (826 vs. 639 g cm-2 day-1). A similar response was observed for fibre diameter (1 9.7 vs. 18.5 pm : P < 0.05). Wool production and fibre diameter did not differ between the ewes supplemented with methionine and cystine and the control ewes during this same period. The ewes supplemented with methionine and cystine produced wool with the greatest sulphur content, and this trait was least in the wool from the control ewes (3.84 vs. 3.64 vs. 3.49: P < 0.05). We concluded that the availability of the sulphur amino acids was not primarily limiting wool production in pregnant/lactating ewes.
The effects of pregnancy and lactation on wool production and liveweight in Polwarth ewes
Authors: Reid RND
Published: March 2005

Groups of Polwarth ewes which 1. were barren, 2, were pregnant but aborted with prostaglandins in early pregnancy, 3. lambed and reared a single lamb and 4. lambed but had their single lamb removed soon after birth, were used to estimate the effects of pregnancy and lactation on wool and Iiveweight. Pregnancy plus lactation reduced liveweight (17 per cent), wool growth rate (9 per cent) and clean fleece weight (11 per cent) ; pregnancy alone reduced liveweight (10 per cent), wool growth rate (7 per cent) and clean fleece weight (10 per cent) and its effects were greater than those of lactation in each of the characters studied.
Nitrogen needs of wheat. 2. Grain yield response to nitrogenous fertilizer
Authors: Taylor AC , Storrier RR , Gilmour AR
Published: March 2005

In southern New South Wales, the increase in wheat yield due to nitrogenous fertilizer (34 kg N ha-1) was examined against a wide range of controlled and uncontrolled factors over three years in which rainfall was generally above average. The controlled factors included paddock history, cultural aspects and a range of nitrogen soil tests. Multivariate regression procedures were used in the examination. Average annual rainfall was a major determinant of fertilizer response patterns. Overall, soil nitrate (0-30 cm) was superior to paddock history and to other soil tests in predicting responses to added nitrogen. In the west (average annual rainfall 400 to 550 mm), nitrogen applications were profitable when soil nitrate levels were low, but only if growing season rain was at least average. At each soil nitrate level, responses to applied nitrogen declined as average annual rainfall increased. In the east (average annual rainfall greater than 550 mm), responses to added nitrogen were profitable at all nitrate levels, provided growing season rain was not limiting. The magnitude of the responses was related to the level of potentially available nitrogen in the soil (0-10 cm) rather than to nitrate.
Plant population and row spacing for irrigated and rainfed oilseed sunflowers (Helianthus annuus) on the Darling Downs
Authors: Radford BJ
Published: March 2005

Effects of plant population and row spacing on the growth and yield of irrigated and rainfed oilseed sunflowers were investigated by means of factorial trials on the heavy clay soils of the Darling Downs, Queensland. General yield and oil levels and treatment responses were determined principally by water availability. Plant population x row spacing interactions were recorded but were considered of no consequence. Responses to population treatments varied in individual experiments, but in general highest oil yields were obtained with populations of 50,000 to 100,000 plants ha-1 in irrigated trials and 40,000 to 60,000 plants ha-1 in rainfed trials. Rows 36 cm wide outyielded 108 cm rows in five out of seven trials. Where paired rows were tested in three rainfed trials, no advantage over evenly-spaced rows was recorded.
The distribution of Tylenchulus semipenetrans and other parasitic nematodes associated with citrus in northern Victoria
Authors: Brown RH
Published: March 2005

Citrus orchards in the Cobram district of northern Victoria were surveyed in 1976 for the presence of plant parasitic nematodes; in particular for the citrus nematode Tylenchulus semipenetrans. One hundred and forty-six soil samples were collected from 38 orchards. Nine genera were recorded, the most prevalant being Tylenchulus and Paratrichodorus (95 per cent and 37 per cent respectively, of all samples). T. semipenetrans was present in all orchards sampled. Population levels of T. semipenetrans larvae exceeded 1000 per 500 g of soil in 60 per cent of samples.
Susceptibility of Fuerte avocado fruit at various stages of growth, to infection by anthracnose and stem end rot fungi
Authors: Peterson RA
Published: March 2005

In a series of field experiments, Fuerte avocado fruit (Persea americana) were susceptible to infection by Glomerella cingulata var. minor (Colletotrichum gloeosporioides var, minor) and Dothiorella aromatics, from set until harvest. Natural infection was detected from December to May and field inoculations demonstrated that small fruit in October were also susceptible. The time of infection varied with the season and was related to rainfall incidence. The significance of this finding is discussed.
Pedigree Dorset Horn sheep in Australia. 1. Breed expansion and other vital statistics
Authors: Fogarty NM
Published: March 2005

The Dorset Horn in Australia is maintained almost exclusively for producing rams for crossbreeding in the prime lamb industry. Flock Book records have been used to assess the expansion and other statistics of the breed. Dorset Horn sheep were first imported in 1895 with the first flock registered in 1920. The number of pedigree flocks increased to 1298 in 1958 and total ewes to 11 3,762 in 1968. Flocks declined to 61 4 and ewes to 60,801 in 1973, during which there was a rapid expansion in Poll Dorset flocks and ewes. Early expansion of the Dorset Horn occurred in South Australia and Victoria but over 85 per cent of flocks and ewes were located in New South Wales and Victoria in 1973. In 1973,40 per cent of flocks contained less than 51 ewes with only 2.8 per cent having more than 400 ewes. The mean age of studs in 1973 was 15.3 years, with 22 per cent established for 0 to 5 years, compared with 7.1 years and 62 per cent respectively in 1958. Stud dispersals have increased dramatically in recent years to 19.7 per cent of extant studs in 1973. Examination of flocks present in 1969 but dispersed prior to 1974, showed the proportion of dispersed flocks decreased with increasing flock size and increasing stud age, up to 40 years. Migration of sires between all regions was low, but of the migrant sires, South Australia supplied 76 per cent in 1954 and the central western region of New South Wales 57 per cent in 1974. Approximately half of the rams sampled had sires bred in the same stud.
Pedigree Dorset Horn sheep in Australia. 2. Breed structure and genetic analysis
Authors: Fogarty NM
Published: March 2005

Flock Books were used to determine the breed structure of pedigree Dorset Horn sheep in Australia. Four-generation ram sample pedigrees were used to determine important flocks in 1954, 1969 and 1974. Two-line ram sample pedigrees traced to foundation or imported animals were used to determine important animals and the level of inbreeding and its components in the same years. A hierarchical breed structure was found to exist. Only 15 to 18 per cent of flocks were Breeders' Flocks, i.e. supplied rams to other pedigree flocks, and only one-third of these supplied rams to other Breeders' Flocks. The effective number of flocks supplying sires in the third and fourth generations was two to three in 1954 and four to five in 1974 and 1969. One flock, Newbold, had a genetic contribution of over 40 per cent in 1954. Two flocks had a genetic contribution of over 20 per cent each, with five flocks having a combined genetic contribution of over 62 per cent in 1974. Total inbreeding was 12.5 per cent and increased by 1.5 per cent per generation in the five years to 1974. Current inbreeding was 1.85 per cent in 1974 with 5.0 per cent of matings being parent-offspring and 3.7 per cent paternal half-sib. Expected long-term inbreeding (7.9 per cent) was the major component, which was caused by few animals being used extensively in the development of the breed. One sire had a direct relationship of 30 per cent to rams registered in 1974. Implications of the high level of inbreeding are discussed as well as development of breed improvement schom3s within the existing breed structure.
Oat forage and grain supplements for the production of yearling beef from pasture on the Northern Tablelands of New South Wales
Authors: Hennessy DW , Robinson GG
Published: March 2005

The use of supplements of oat grain alone, or with silage or hay, to produce marketable yearling cattle ('finished' and >270 kg) in October was assessed at Glen lnnes on the Northern Tablelands of New South Wales. The assessment was made over three years. Weaned cattle grazed improved pastures (mainly Phalaris tuberosa and Trifolium repens) from March, with or without forage oats (Avena sativa) from June to October, when the supplements were also given. When grain supplements were given to weaner cattle grazing pasture only, 24 per cent were 'finished' compared with none without grain supplements, but the supplements were not justified economically. When oat grain supplements were given to weaners grazing pasture and forage oats, 60 per cent were 'finished' by October compared with 8 per cent without the grain; the supplements were economically worthwhile when cattle were valued at 37c kg-1 liveweight. There was no apparent substitution by the cattle of grain for herbage over the whole period in the supplemented treatments, with from 5.7-10.8 kg of grain required for every kg of additional liveweight gain. The effectiveness of grain supplements and the efficiency of gain were reduced when grain was partially replaced by either silage or hay.
Sheep production on a Danthonia caespitosa-Stipa variabilis grassland in response to fertilizers and deferred grazing
Authors: Tupper GJ
Published: March 2005

The effects of nitrogen and phosphate fertilizers and deferred spring grazing were assessed over five years on the body weight and wool production of Merino wether weaners grazing a Danthonia caespitosa-Stipa variabilis grassland at three stocking rates. Seasonal forage availability, botanical composition of forage, body weight and wool growth of sheep, were measured. Two years after grazing treatments ceased, and three years after the final addition of fertilizer, further measurements were made on the vegetation. There were very few differences in plant and animal response between the continuously and deferred grazing systems. Forage availability increased on fertilized grassland at all stocking rates by up to 50 per cent. Danthonia caespitosa, Stipa variabilis, perennial chenopods, and annual herbs contributed to the increase in forage present. Medicago polymorpha became prominent on all fertilized grassland. At 2.0 and 2.7 sheep ha-' without fertilizer, and 2.7 sheep ha-1 with fertilizer, the relative contribution by the more palatable species decreased and Eriochlamys behrii increased greatly. After grazing treatments ceased, this trend was reversed. Sheep body weight and wool growth rates were increased on fertilized grassland. In September 1971, at 2.0 sheep ha-1, the body weights of sheep on unfertilized and fertilized grassland were 35.0 and 45.2 kg, respectively, and the clean fleece weights were 3.2 and 4.3 kg per sheep, respectively. Animal production from this grassland can be increased with the addition of fertilizer to the grassland and by increasing the stocking rate by about 50 per cent above the district average of 1.2 sheep per hectare.
The effect of spectacles, a whole grain diet and dietary level of citranaxanthin on egg yolk colour, nesting behaviour and laying performance of crossbred hens
Authors: Karunajeewa H , Bagot I
Published: March 2005

In a 2 x 2 x 2 factorial experiment, the laying performance of 800 crossbred hens with or without spectacles and fed either whole wheat plus concentrate or a conventional mash diet supplemented with one of two levels of citranaxanthin was measured. Hens fitted with spectacles ate 9 per cent less feed, converted feed more efficiently, were better feathered and had lower daily intakes of protein, metabolizable energy, calcium and phosphorus than those without spectacles. Their rate of egg production was similar to that of hens without spectacles but egg weight was reduced and consequently these eggs had higher Haugh unit scores. They also tended to lay more eggs on the floor but the height of nests did not seem to influence their choice of nests. The dry weight of their skin plus feathers was 10.5 per cent lighter than that of the hens without spectacles. Hens fed whole wheat plus concentrate on a free choice basis ate 13.5 per cent less feed with no reduction in rate of lay or egg size, converted feed more efficiently, gained more liveweight, consumed less protein, energy, calcium and phosphorus per day than those given the mash diet. These hens showed a marked preference for nests at the lower level and tended to lay eggs with lower yolk colour scores. A 21 per cent reduction in feed intake was achieved when the two techniques of fitting spectacles and feeding whole wheat plus concentrate were combined. In diets containing natural xanthophylls, citranaxanthin at inclusion levels of 1.5 and 6.0 p.p.m. in mash and concentrate diets respectively, produced eggs with acceptable yolk colours.
Biological control of Eutypa armeniacae. 4. Design and performance of an applicator for metered delivery of protective aerosols during pruning
Authors: Carter MV , Mullett LF
Published: March 2005

The paper describes the development of a prototype applicator for delivery of protective mixtures, in aerosol form, to the wounded sapwood surfaces exposed during pruning. The equipment has three components : a 2 litre day-service tank, a light weight belt-mounted piston pump, and a modification of a standard pneumatic-powered pruning handgun. Laboratory tests of the applicator have proved its ability to deliver, repeatedly, a uniform dose of aerosol containing sufficient particulate chemical and/or biological matter to protect apricot sapwood from invasion by Eutypa armeniacae. Field tests of the equipment in two orchards demonstrated that from 90-100 per cent of wounds can be treated for the addition of less than 20 per cent to the time required to prune a tree. Over a period of three weeks' use no mechanical defects developed. Estimated volume of protective fluid required per day, treating up to 90 per cent of wounds, is less than two litres.
Post-harvest disinfestation of apples of the light-brown apple moth Epiphyas postvittana
Authors: Terauds A , Ireson JE , Rapley PEL , O'Loughlin JB
Published: March 2005

A range of dosages of methyl bromide used according to different chamber and fru:. I+ temperatures, preceded, unaccompanied or followed by cold treatment was found effective in disinfesting apples of the light-brown apple moth, Epiphyas postvittana (Walker), in Tasmania, 1972-1 974. Fumigations were in 1.1 m3 and 14.3 m3 chambers, for 2 or 2+hours, loaded to 40 or 80 per cent of their capacities, and cold storage was for 21 days at 0�C. The disinfestation treatments were tested on apples artificially infested with neonate and fourth instar larvae and on a field line of naturally infested fruit; the onset of fumigation effects on fourth instar larvae in artificial medium was also determined.
The distribution, live sampling for and decline of DDT in steers
Authors: Blunt CG , Saunders PJ
Published: March 2005

Following DDT contamination of steers grazing pastures polluted by spray-drift from nearby crops in the Ord Valley of Western Australia, experiments were conducted to determine: 1, the distribution of DDT and metabolites (referred to hereafter as DDT) within the carcase fat tissues; 2. a suitable method of sampling fat from live steers; 3. the rate of decline under local feeding conditions with maintenance feeding for 201 days and with ad lib feeding for a further 156 days. There was no significant difference between the DDT concentrations found in the renal, omental, subcutaneous and scrotal fat. A method of sampling fat from the scrotum permitted repeated sampling of steers in good condition at an operation rate of 15 animals per hour. DDT was lost at a mean rate of 0.0031 log mg kg-1 DDT day-1 during the maintenance feeding period despite a level of 1.5 mg kg-1 DDT in the feed. During the ad lib feeding period the loss was 0.0014 log mg, kg-1 DDT day-1. The distribution of DDT values in the experimental herd was skewed; the implications of this on the amount of sampling necessary to ensure that no animal in a group will exceed minimal accepted values of DDT are discussed.
The development of lucerne with resistance to root rot in poorly aerated soils
Authors: Rogers VE , Irwin JAG , Stovold G
Published: March 2005

Three cycles of recurrent mass selection in the field increased the level of resistance of lucerne (Medicago sativa) to Phytophthora root rot in irrigated heavy clay soil at Deniliquin, New South Wales. The breeding stocks were derived from Siro Peruvian and Lahontan. In each cycle between 45 and 80 vigorous, disease free plants were selected from soil naturally infested with Phytophthora megasperma var. sojae, and allowed to interpollinate. Yield data and ratings for root rot were obtained for half-sib families sown in rows. Progeny in cycle 1 were inoculated by isolates of P. megasperma from both New South Wales and Queensland, and there was substantial agreement between both sources in ratings for disease. In the third cycle of selection, progeny had a disease rating of 1.4 when inoculated with Queensland isolates of P. megasperma, compared with 3.6 and 4.1 for Hunter River and Siro Peruvian respectively (plants scored 1 or 2 considered resistant; 3, 4 or 5 susceptible). In a field trial, the percentage of disease-free plants after eight months of growth in infested soil was: cycle 3 selections, 44.4; Hunter River, 9.9; Siro Peruvian, 12.0. Cumulative dry matter production of the selections during that time was twice that of Hunter River.
Comparison of lupin varieties for grain yield, nutritive value of stubbles, incidence of infection with Phomopsis leptostromiformis and occurrence of lupinosis
Authors: Arnold GW , Wood PM , Nairn M , Allen J , Wallace SR , Weeldenberg J
Published: March 2005

The lupin cultivars Borre, Uniwhite, Fest, Uniharvest, Weiko III, CB46 and Ultra were grown for two years at Baker's Hill, Western Australia (640 mm average rainfall). Fest gave the highest grain yield in both years but the ranking of the other cultivars differed in the two years. Grain lost at harvest varied from 24 to 860 kg ha-1, being significantly higher from Weiko Ill and CB46. The nitrogen content of the grain of Weiko III and Ultra was significanlty higher than that in all other cultivars, and the pods of Ultra had a higher nitrogen content than pods of any other cultivar. In both years the stems and pods of Weiko Ill and Ultra had significantly lower concentrations of soluble carbohydrates, the stems fewer lesions from Phomopsis, and the sheep grazing the stubbles a much lower and less severe incidence of lupinosis than on all the other cultivars. In the first year liveweight gains over 63 days ranged from 2.9 kg on Fest to 7.5 kg on Borre. In the second year, when lupinosis was severe, there was a positive correlation between its severity and concentration of copper in the liver, and a negative correlation with zinc concentration. In another experiment Ultra and Unicrop had fewer Phomopsis lesions than CB46 and sheep grazing the stubbles less liver damage. Dry ewes grazed on stubbles of Uniharvest lupins planted at three different dates and on Fest lupins barely maintained weight but those grazed on wheat stubble lost 6.5 kg in 42 days. Stubbles from Uniharvest lupins sown at four different dates in two years all produced lupinosis when fed to sheep in pens. The diet selected by sheep from the stubbles was measured in two of the experiments. In both, stem, which is the most toxic fraction, made up at least 80 per cent of the diet from the time grazing started.
A comparison of Charolais × Jersey and Friesian animals for vealer and steer beef production
Authors: Mickan FJ , Spiker SA , Hallett RH
Published: March 2005

Charolais sires were mated to Jersey dams and the progeny compared with Friesians for vealer (33 weeks) and steer (90 weeks) beef production. Nurse cows double-suckled one vealer of each breed. No significant difference in growth to slaughter between the Charolais x Jersey (C x J) and Friesian (0.79, 0.70 kg day-1 respectively) was recorded. The C x J vealers produced a significantly heavier carcase. Neither breed had sufficient fat cover (< 0.3 mm) for vealer production. No breed difference existed in the edible meat and fat proportions but the Friesian carcase had a larger percentage of bone. C x J had a significantly greater proportion of hindquarter in the carcase than the Friesian but no breed difference was recorded for either high or low priced cuts. Plunketting showed no difference in milk intake between breeds, but 24-hourly observations revealed that the C x J animals were usually the first to arrive at and last to leave the suckled cow. Steers double-suckled to weaning (1 2 weeks) and then run together until slaughtering gained 0.56 kg animal-1 day-1. There was no breed difference in carcase weights but the C x J had a significantly higher dressing percentage (53.1 vs. 50.5) and 25.3 per cent greater area of eye muscle. Again, fat thickness of the C x J (2.1 mm) and Friesian (1.8 mm) was far below the optimum (7-10 mm) required for the local market.
Effects of varying phosphorus intake and requirement on measures of skeletal mineralization in the ewe
Authors: Little DA , Siemon NJ , Moodie EW
Published: March 2005

Merino ewes were fed a specifically phosphorus-deficient ration, with or without supplementary phosphorus, for 20 weeks, spanning approximately the last 5 weeks of gestation and a 15-week lactation. Non-lactating ewes were employed as controls. No significant differences occurred between groups in liveweight change of ewes or lambs, nor did the groups differ in the mean interval from weaning to first oestrus. Biopsy samples of rib bone taken at the beginning and end of treatment showed significant loss of bone mineral by the end of lactation; ewes suckling twins lost 42 per cent of bone phosphorus, and those with single lambs, 17 per cent. Feeding supplementary phosphorus prevented the significant loss of bone mineral. Fortnightly measurement of the bone density of the hock by radiation absorption also showed differences dependent upon the number of lambs suckled, but failed to detect any effect of phosphorus supplementation. The detection of significant skeletal changes in the absence of effects on production demonstrates the sensitivity of these measures as indices of variations in phosphorus storage. The greater sensitivity of observations on rib bone is probably a reflection of differences between bones in the degree of lability of mineral.
Comparative nutritive value of hay made normally and by desiccation with paraquat
Authors: Arnold GW , Barrett DW
Published: March 2005

In a series of five experiments, hay made by conventional methods was compared with hay made by spraying with paraquat prior to mowing. In all the experiments, chemical composition of the hays was measured and in three of them the hays were fed to sheep. In the first experiment the digestible organic matter intake (DOMI) and digestibility of oaten hay made by the two methods was similar. In the second experiment rapid desiccation was achieved using paraquat on a pasture of Wimmera ryegrass (Lolium rigidum) and subterranean clover (Trifolium subterraneum), but leaf losses during baling were higher than for turning and baling mown herbage. In the third experiment, on a densestand of Wimmera ryegrass, the stem bases were not reached by the paraquat spray and desiccation took 14 days longer than with mowing and turning. In both experiment 2 and 3 sheep consumed similar amounts of DOMIand had similar liveweight changes when fed the two types of hay, although digestibilities were lower for the hays made using paraquat. Also, in these two experiments there were higher concentrations of cell wall constituents, and in experiment 3 lower concentrations of water soluble carbohydrates (WSC), in hay made by using paraquat. In experiments 4 and 5 it was shown that large losses of WSC occurred consistently when herbage on ryegrass pastures was desiccated with paraquat. The effect was shown to occur within 24 hours of application. A further effect, that needs more research, was that the digestibility of cell wall material was lower in hay made with paraquat than in normal hay. It is concluded that the use of paraquat to provide rapid desiccation of herbage is unlikely to result in hay of higher quality than that made conventionally.
Nitrogen and phosphorus nutrition of dryland grain sorghum at Katherine, Northern Territory. 1. Effect of rate of nitrogen fertilizer
Authors: Myers RJK
Published: March 2005

Responses of dryland grain sorghum to applied nitrogen were examined in three field experiments at Katherine, Northern Territory, in 1969-70, 1970-71 and 1971-72. Rates of nitrogen up to 89 kg ha-1 in the first season and up to 200 kg ha-1 in subsequent seasons were used. The crops were sampled at floral initiation, mid-elongation, anthesis, and maturity. The three growing seasons were rated as below average, above average and average, respectively, for grain sorghum production. Nitrogen response was strongly season-dependent, Maximum yields (adjusted to 14 per cent moisture) were: 1969-70, 2280 kg ha-1, with 22.4 kg N ha-1 applied (with lower yields at higher rates of nitrogen) ; 1970-71,7730 kg ha-1 with 150 kg N ha-1 applied; and 1971-72,4440 kg ha-1 with 200 kg N ha-1 applied. These represented increases of 6, 50, and 62 per cent, respectively, over the zero nitrogen treatments. Applied nitrogen increased grain numbers per head and individual grain weight, but had no significant effect on head numbers. Applied nitrogen increased yields of nitrogen and phosphorus in plant material, and increased nitrogen concentration in plant parts. Apparent recoveries of nitrogen fertilizer ranged from 0 to 40 per cent, depending on year and rate applied. An approximate balance sheet suggested substantial losses from the mineral nitrogen pool in 1970- 71, a year of above average rainfall. Significant interactions between nitrogen and phosphorus fertilizer occurred only with grains per head and thousand grain weight.
The mineral content of cereals, grain legumes and oilseed crops in South Australia
Authors: Schultz JE , French RJ
Published: March 2005

Samples of barley, oats, lupins, peas, rape, linseed and safflower were analysed at five growth stages for nitrogen, phosphorus, potassium, sulphur, calcium, magnesium, sodium, chlorine, silicon, copper, zinc and manganese. The results are summarized and compared with those for wheat published in a previous paper. The data are discussed in relation to nutrient removal and the effect on soil fertility.