bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of rootstocks for five lemon scions in replant ground
Authors: Freeman B , Broadbent P , Nicholls P
Published: March 2005

In an experiment planted in 1971 at the Horticultural Research Station, Somersby, N.S.W., nucellar lemons (Lambert and Taylor Eureka, Villafranca and Prior Lisbon) and 1 old-line cultivar carrying exocortis (Monroe Lisbon) were compared on 5 rootstocks (Troyer citrange, Narara Rough lemon, Rangpur lime, Smooth Seville and trifoliate orange). In the second experiment, planted in 1973, 2 nucellar lemon scions (Taylor Eureka and Prior Lisbon) were compared on 16 rootstocks (4 Rough lemons, 4 Smooth and 1 Rough Seville, New Guinea citron, citremon 1449, Poorman orange, 3 citranges and trifoliate orange). Eureka lemon selections on Troyer citrange and trifoliate orange rootstocks exhibited symptoms of yellow ring incompatibility. Eureka lemon, however, was compatible with Benton citrange; cumulative yield and cropping efficiency were high and tree canopies dense and compact. Trees on Narara and Watkins selections of Rough lemon had high cumulative yields but their size and vigour made harvest difficult. One of the red Rough lemon selections (57-228-502) produced a high yielding and more manageable compact tree with a large proportion of summer crop fruit. Prior Lisbon lemon on trifoliate orange was a medium-sized, compact tree with high cropping efficiency and good juice quality. Villafranca performed well on all rootstocks except Smooth Seville. The results are discussed with respect to planting densities, proportion of summer and main crop fruit and juice yield and quality.
Effects of waterlogging and soil salinity on irrigated agriculture in the Murray Valley: a review
Authors: Grieve AM , Dunford E , Marston D , Martin RE , Slavich P
Published: March 2005

A physical model was used to assess the effects of surface waterlogging and soil salinity on the productivity of winter cereals and irrigated dairy pastures on irrigation farms in the Berriquin and Wakool Irrigation Districts of the Murray Valley region of New South Wales. Parameters describing the physical properties of major soil types were combined with statistically derived estimates of rainfall excess over evapotranspiration to establish the incidence of waterlogging. Soils predisposed to waterlogging occupy 150000 ha of Berriquin District (45% of District) and 24 800 ha of Wakool District (73%). Estimates of yield losses from waterlogging ranged from 12.5% in annual subterranean clover-based pastures, 20% in winter cereals, to 25% for perennial ryegrass-white clover pastures. The relationships between yield and soil salinity were determined for barley, wheat, white clover, subterranean clover, and irrigated annual and perennial pastures growing under existing management practices in shallow watertable areas of the 2 Districts. Response functions were applied to soil salinity frequency distributions to derive production loss coefficients. Surveys showed that average soil salinities were lower in Berriquin than in Wakool. In 1984, 43% the soils in shallow watertable areas of Berriquin could be classed as saline, whereas, in 1982 the corresponding figure for Wakool was 72%. A further survey taken in 1984, 2 years after the inception of a deep drainage scheme, showed that saline soils in Wakool had decreased to 46% of the total area.We assessed economic losses associated with soil salinity and waterlogging by applying the derived loss coefficients to achievable yields for known production areas. Total annual losses for the 2 Districts exceeded $A13 million, or 16% of the 1984 value of the District's agricultural production. This figure underestimates real losses because we excluded livestock enterprises other than dairying, as well as summer cropping, from the study. Losses due to waterlogging ($A10 million overall) were more serious than those due to soil salinity (nearly $A4 million), particularly in Berriquin where shallow watertables were less extensive. In Wakool, 2 years' operation of the deep drainage scheme reduced losses due to soil salinity by $A750 000.Thus surface waterlogging and soil salinity cause serious economic losses in the irrigated areas of southern New South Wales. Research into appropriate techniques for on-farm irrigation management may reduce these losses, and delay further development of shallow watertables and soil salinisation, with sub of stantial economic and environmental benefits.
Reproductive performance and calf growth to weaning of Hereford and Belmont Red cattle in subtropical, subcoastal Queensland
Authors: Coates DB , Mannetje L , Seifert GW
Published: March 2005

The reproductive performances of herds of Belmont Red (BR) and Hereford (H) breeding females were compared at Narayen Research Station in south-eastern Queensland on cleared and sown brigalow land (Brigalow) and on native speargrass pastures with trees killed (Speargrass). The conception rates (BR, 83%; H, 83%) and calving rates (BR, 80%; H, 78%) were similar, but BR calves grew faster (P<0.001) than H calves especially on Speargrass where BR had a 13% advantage. The mean calving date of H was 13 days earlier than BR (18 days on Speargrass; 7 days on Brigalow). Values for the weight of calfweaned per cow mated for BR and H respectively were 195 kg and 181 kg on Brigalow, and 155 kg and 140 kg on Speargrass. Breed x pasture-type interactions were significant for cow weight, time of calving and calf weight-for-age at weaning. There were significant effects of pasture type on animal performance. Compared with Speargrass, cows on Brigalow were heavier, they calved earlier and their calves grew faster. Production, measured as weight of calf weaned, was 3 times higher on Brigalow than on Speargrass per unit area and 30% higher per cow mated.
Effect of grazing intensity in spring on pasture growth, composition and digestibility, and on milk production by dairy cows
Authors: Michell P , Fulkerson WJ , Michell PJ
Published: March 2005

Two 20-block farmlets, each of 6.5 ha, were rotationally grazed by milking cows in spring at stocking rates of 1.9 and 3.4 cows/ha to give a low (LGI) or high (HGI) grazing intensity. These grazing intensities were designed to simulate dairy farms with low or high levels of pasture conservation, and resulted in post-grazing residues of2.6 (LGI) and 1.7 (HGI) t/ha DM by late spring. Over summer, the 2 groups of cows continued to graze their respective areas, but spare cows were re-allocated between the groups so that stocking rates were the same at 1.7 cows/ha. The HGI cows produced 1 kg less milk fat (0.79 v. 0.81 kg/day.cow, P> 0.05) in spring (15 October-30 November), but produced significantly (P < 0.05) more milk fat (0.63 v. 0.59 kg/day.cow) and 1.3 kg milk protein (0.44 v. 0.42 kg/day.cow) in summer (1 December-1 February). Despite the higher grazing intensity in spring. there was no difference in intake of pasture or in digestibility of herbage selected by the cows in the two herds. In summer the HGI swards contained less dead herbage (P<0.05) but a similar quantity of green herbage compared with the LGI swards, and, compared with LGI cows, the HGI cows removed a higher proportion of this green herbage during grazing. Digestibility of the LGI swards was lower because of the higher content of dead herbage but cows in both groups rejected this dead material and selected a diet of similar digestibility. The presence of dead herbage in the LGI swards appeared to reduce animal production by reducing availability and intake of green herbage rather than by reducing the digestibility of the diet selected by the cows. The high grazing intensity increased daily net accumulation of grass leaf in spring (1 7 v. 6 kg/ha of DM, P< 0.05) but reduced that of true stem (-4 v. 28 kg/ha, P < 0.10) and of total herbage (43 v. 54 kg/ha, P<0.10). The HGI swards had higher ryegrass tiller densities in summer and higher (P<0.05) net accumulation rates of herbage in summer through to winter). Increased grazing intensity in spring above normally accepted levels increased pasture utilisation in spring and summer, and milk production in summer, and increased the quantity of spring herbage available for conservation.
A rat bioassay for screening tropical legume forages and seeds for palatability and toxicity
Authors: Strickland RW , Lambourne LJ , Ratcliff D
Published: March 2005

A rapid evaluation of palatability and apparent toxicity of forage legumes, using a rat bioassay and requiring only 400 g of dried forage or 100 g of seed, is described. Vegetative material is included as 20%, or seed as 5%, of a nutritionally complete, 12% protein (casein) diet for rats. Voluntary intake and weight gain of rats on test diets are compared with results from standard diets given ad libitum and at restricted rates. It proved possible to distinguish toxicity from simple unpalatability by comparing the weight gain observed on test diets, with the expected weight gain estimated from the regression of weight gain on intake of the standard diet. The method is satisfactorily reproducible, and discriminated clearly between commercially acceptable forages and others known to be toxic, between young and old or between leaf and stem material of the same plant, and between raw and autoclaved seed. The method was used to screen forage from 340 accessions and seed from 110 accessions held in the Australian Tropical Forages Genetic Resources Centre of the CSIRO Division of Tropical Crops and Pastures. Of 150 species, mostly in the genera Cassia, Crotalaria, Indigofera and Tephrosia, only 40 could be classified as palatable and non-toxic to rats, though there was considerable variation between accessions of some other species. As the rat, which is the common laboratory test animal for plant compounds harmful to poultry, man and other monogastric animals, is likely to be more sensitive to ingested phytotoxins than ruminants in most cases, the technique provides a fast, cheap, conservative, preliminary screen of potential forages.
Combined effects of leaf spot diseases caused by Stemphylium vesicarium (Wallr.) Simmons and Leptosphaerulina trifolii (Rostr.) Petr. on lucerne cultivars, and the efficacy of some fungicidal control methods
Authors: Lowe KF , Langdon PW , Bowdler TM
Published: March 2005

Relative leaf damage caused by the combined effects of 2 leaf diseases, stemphylium leaf spot and leptosphaerulina leaf spot (caused by Stemphylium vesicarium [Wallr.] Simmons and Leptosphaerulina trifolii [Rostr.] Petr.), was monitored in 2- and 3-year old stands of commercial and experimental lucernes (Medicago sativa L.) in subcoastal south-eastern Queensland. A range of fungicides was evaluated for efficacy in reducing damage caused by both diseases. None of the 38 lucerne cultivars tested showed substantial resistance to these diseases. The level of damage resulting from a severe infection was significantly (Pt0.001) and positively related to the relative winter activity level of the cultivar. Of the 8 fungicides evaluated, iprodione and propineb were the most effective, reducing the amount of leaf damage relative to the untreated areas. The most effective rate of application was a spray concentration of 0.1% product, applied at 300 L/ha. All rates were most effective when applied every 10 days. Although the increase in yield in response to fungicide application was less consistent than that of lesion suppression, up to a 90% yield increase over that of untreated areas was measured.
A high performance liquid chromatographic assay for the mycotoxin phomopsin A in lupin stubble
Authors: Hancock GR , Vogel P , Petterson DS
Published: March 2005

An assay using high performance liquid chromatography to measure phomopsin A, the principal mycotoxin responsible for lupinosis is described. Samples of lupin stubble are extracted with methanol: water and purified by partitioning between n-butanol and water, chromatography on Amberlite XAD-2 and by cation exchange chromatography. The analysis is performed on a reverse phase C18 column using a methanol:water gradient and UV detection. The limit of detection for this procedure is 0.5 mg phomopsin A per kg stubble. Improvements to the extraction and purification procedures were made and total analysis time was reduced to 2 days. The mean (� s.d.) recovery for the purification procedure was 64.3 � 4.5% over a wide range of concentrations.
Effectiveness of topdressed and incorporated superphosphate and Duchess rock phosphate for subterranean clover on sandy soils near Esperance Western Australia
Authors: Bolland MDA
Published: March 2005

In 2 experiments on sandy soil near Esperance, W. A., superphosphate and Duchess (Queensland) apatite rock phosphate were either left on the soil surface after application (topdressed) or incorporated into the top 10 cm of the soil with a rotary hoe (incorporated). One experiment was on Fleming gravelly sand which had a greater capacity to adsorb phosphorus than did the deep yellow sand (Gibson sand) used in the other experiment. Dry matter or seed yield of subterranean clover and phosphorus content of dry herbage or seed were used as indicators of the effectiveness of the phosphorus treatments. Compared with topdressed superphosphate, incorporation of superphosphate did not greatly influence its effectiveness on the Gibson soil, but reduced its effectiveness by about 20% on the Fleming soil. Relative to topdressed rock phosphate, incorporation of rock phosphate almost doubled its effectiveness on the Fleming soil, and improved its effectiveness by about 1.5 times on the Gibson soil. Superphosphate was the more effective fertiliser. Relative to topdressed superphosphate, the effectiveness of topdressed and incorporated Duchess rock phosphate, respectively, was about 15 and 30% on the Fleming soil, and about 25 and 40% on the Gibson soil. There was no evidence of any leaching of phosphorus from Duchess rock phosphate from the 0-10 cm layer of either soil, nor of superphosphate on the Fleming soil. However, on the Gibson soil, there was some leaching of superphosphate to below 10cm, but not below 20 cm.
Fertility assessment of soils of the Mt Garnet area, North Queensland
Authors: Gilbert MA , Moody PW , Shaw KA
Published: March 2005

Surface soil samples (0-l0cm) were collected from 47 sites covering the range of soil types in the Mt Garnet area of Queensland. The soils are slightly acid, have low phosphate buffer capacity, and contain low levels of organic carbon, total nitrogen, exchangeable basic cations, DTPA-extractable zinc and copper, acid-extractable phosphorus and phosphate-extractable sulfur. In many soils, phosphate-extractable sulfur levels were higher at depth 70-80 cm than in the surface 10 cm. In glasshouse experiments, Stylosanthes hamata cv. Verano was grown on 7 different soils selected as representative of the range in soil chemical characteristics. Dry matter yield responses to phosphorus, sulfur and zinc were measured. Field experiments at 2 sites confirmed the deficiencies of phosphorus and sulfur, but not of zinc. From the results of all of these techniques, we conclude that a single superphosphate (9% P; 10% S) application of 560 kg/ha is necessary to maximise yield of legume-based pastures on these soils. However, applications equivalent to 140 and 280 kg/ha increased yield and had strong residual effects which lasted into the second growing season.
Emergence and survival of buried doublegee (Emex australis Steinh.) seeds
Authors: Cheam AH
Published: March 2005

The emergence and survival of seed of doublegee (Emex australis Steinh.) buried at various depths were studied over 4 years at 3 climatically contrasting sites in Western Australia. We concluded that there is an optimal burial depth for seedling emergence and seed survival. Seeds placed at 1 cm gave maximum emergence but no seedling emerged from seeds placed at 15 cm or deeper. Emergence occurred mainly during the first autumn from seed less than 1 year old. Over the following 3 years, emergence declined progressively. The waves of emergence reflected the seasonal rainfall pattern, although emergence did not occur after every rainfall. There was no direct relationship between emergence and loss of seed viability. At the coolest site with higher rainfall the retention of viable seeds increased with increasing depth in the soil, whereas at warmer sites with lower rainfall there was an inverse relationship between viability and burial depth. The viable seeds exhumed after 4 years of burial were in different states of dormancy but induced or innately dormant seeds predominated at the cooler higher rainfall site. These types of dormancies and the various environmental factors will determine the number of viable seeds germinating in any given season. It is shown that even when the influx of new seed was stopped for 4 consecutive years, it was still not possible to achieve complete reduction in numbers of doublegee seeds.
Effect of constant and fluctuating temperature regimes and seed source on the coleoptile length of tall and semidwarf wheats
Authors: Radford BJ
Published: March 2005

Laboratory experiments were carried out to determine the effects of constant and fluctuating temperature regimes on the final coleoptile length of 8 wheat cultivars (Banks, Cook, Gatcher, Hartog, Kite, Oxley, Shortim and Spica) and the effect of environmental conditions during seed maturation (seed source) on the coleoptile length of 5 cultivars (Banks, Bass, Cook, Kite and Oxley). Mean coleoptile length decreased from 10.8 cm at 15�C to only 3.1 cm at 35�C, a reduction within this temperature range of 1 cm for every 2.6�C rise in temperature. This indicates that, in warm soil, shallow sowing is necessary for satisfactory wheat establishment. Fluctuating temperatures (� 5�C about the mean) further reduced coleoptile length. The temperature x cultivar interaction was significant, differences among cultivars in coleoptile length occurring more at low than at high temperatures. The mean coleoptile lengths of the 8 cultivars varied from 8.7 to 14.5 cm at 15�C, but only from 2.7 to 3.6 cm at 35�C. Tall wheat cultivars (Gatcher and Spica) generally had longer coleoptiles than the 6 semidwarf cultivars. Tall wheats also had near-maximum coleoptile length at a wider range of temperatures than semidwarfs. Different environmental conditions during seed maturation (glasshouse v. field) changed the ranking of cultivars with respect to coleoptile length. The coleoptiles of Cook and Oxley were significantly longer when seed was field-ripened rather than glasshouse ripened, while those of Banks, Bass and Kite were similar in length under both ripening environments.
Water use by irrigated potatoes on a duplex soil
Authors: Rab MA , Willatt ST
Published: March 2005

Potatoes (Solanum tuberosum cv. Sebago) were grown near Melbourne on a duplex soil during November-May under 3 irrigation schedules: TI, wet (irrigated every 5-9 days); T2, medium (irrigated every 12-1 7 days); and T3, dry (irrigated every 36 days). Root distribution was studied for the plants from the tuber setting stage in January, through flowering to tuber bulking in March; root growth was different in all treatments, significantly (P < 0.05) so on some occasions. The wet treatment T1 had more deep roots early in the growing season (January) than did the drier treatments but, by late February, root length was greatest in the driest treatment. During the latter part of February and March total root length per unit ground area diminished in all treatments, but the reduction was less in the drier treatments (T2 and T3). Root length densities ranged from 7.5 to 40 km/m3. Leaf area index of the crop in T1 was always significantly greater than those of T2 and T3. Between late December and late March the average daily water use for the crop was 5.4, 3.7 and 2.2 mm day-1 for TI, T2 and T3 respectively and, from these data, the relative evapotranspiration rates were calculated as 0.94, 0.66 and 0.38 respectively. Yields of tubers, harvested in May 1983, from T2 and T3, were at least 60% less on a fresh weight basis than from T1. Tuber water percentage at harvest was not affected by different irrigation treatments. Water use efficiency was slightly greater for T1 than for T2 and T3. We conclude that, on this soil, frequent light irrigations are necessary to obtain high yields of potatoes, but care must be taken because of the potential problem of a perched water table.
Time of harvest, prethreshing treatment and quality in snap bean (Phaseolus vulgaris) seed crops
Authors: Siddique MA , Somerset G , Goodwin PB
Published: March 2005

Trials on the cultivars Canyon and Gallatin 50 in 1978 and Cascade in 1979 were run in North Queensland to examine ways of improving seed quality of snap beans. The trials concentrated on the maturation period, since this is a critical period for the development of seed quality. We found that seed quality was poor when the crop was cut at the stage when the leaves had fallen and all the pods were dry, or if the plants were cut at any stage and allowed to dry on the ground in single rows. This poor seed quality was associated with high pod temperatures during seed maturation. Cutting the crop before leaf fall, at a seed moisture content close to 50% (20-40% of pods dry) and windrowing immediately in 5 or 10 rows to 1 windrow gave low pod temperatures during seed maturation and high seed quality. Seed harvested and threshed directly off the crop was of good quality provided the seed moisture content in the crop had fallen to less than 25%.
Effect of repeated anthelmintic treatment on weight gain in Hereford and Brahman crossbred cattle in south-eastern Queensland
Authors: Winks R , Burns MA , Berrie DA , East IJ , Kelly JG , Bremner KC
Published: March 2005

Hereford and Brahman crossbred steers were treated with the injectable anthelmintic, levamisole, at either 3-, 6- or 12-week intervals for 8 months after weaning. Throughout the studies, the different treatment groups were maintained on separate pastures with the exception of 1 group in which half of the animals were treated 3-weekly and the others were untreated. A further untreated group was grazed separately. The trial was repeated with different groups of weaners in 3 successive years. The major gastrointestinal nematodes infecting the cattle were Haemonchus placei, Oesophagostomum radiatum, Cooperia pectinata and Cooperia punctata. The Hereford weaners treated every 3 or 6 weeks showed significantly greater weight gains than untreated steers, but those treated every 12 weeks did not. In 2 of the 3 years. Brahman-cross weaners showed a significant increase in weight gain with the 3-week schedule but not with the 6- and 12-week schedules. Twelve months after treatment ended, the final liveweights of the treated groups did not differ significantly from those of the control groups for either Hereford or Brahman crossbred cattle.
Phenotypic and genetic parameters for lamb and hogget traits in a flock of South Australian Merino sheep
Authors: Walkley JRW , Ponzoni RW , Dolling CHS
Published: March 2005

The heritability of and phenotypic and genetic correlations among weaning weight (WW). greasy fleece weight (GFW), scouring yield (YLD), clean fleece weight (CFW), fibre diameter (FD), crimps per inch (CR) and staple length (SL) were estimated in a flock consisting of a control and 2 selection lines of South Australian Merino sheep. The effects of type of rearing, age of dam and sex were also examined. Estimates were compared with those currently in use in WOOLPLAN (National Performance Recording Scheme for non-pedigreed sheep) and in other studies. In general, agreement between the present study and other estimates was good, but there were some exceptions, namely: (i) standard deviation of GFW and FD; (ii) 'adjustment factors' for day of birth, type of rearing and age of dam for GFW, CFW and liveweight traits; (iii) heritability of YLD; (iv) phenotypic correlations of GFW and CFW with FD, and between YLD and CFW and (v) genetic correlations of WW with GFW, CFW and FD. It is concluded that special attention should be given to these exceptions in order to decide whether alterations to current 'accepted' parameter values are justified.
Supplementary feeding of oat grain or lucerne hay to crossbred ewes at lambing
Authors: Holst PJ
Published: March 2005

Border Leicester x Merino ewes (body condition score 2.6-3.0) grazing short pastures were given feed supplements during lambing, to examine effects on lamb survival. Supplementary feeding of poor quality lucerne hay, good quality lucerne hay or oaten grain, each given ad libitum, began 3 days prior to the start of the 4-week lambing period and continued to the end of lambing. One third of the ewes had twins. Lamb marking percentage for the unsupplemented treatment was 108.5% compared with 109.9, 118.1 and 111.7% for the poor quality lucerne hay, good quality lucerne hay and oaten grain treatments respectively. Of twin-bearing ewes given good quality hay, 60% reared both lambs, compared with 48-49% of those given poor quality hap or grain (n.s.) and 36% of those not supplemented (P < 0.05). Supplements did not improve the survival rate of single lambs. Overall survival (combining birth types) of lambs was also significantly improved by a supplement of good quality hay. The observed differences in twin survival were associated with differences in ewe grazing behaviour. These results support recommendations that supplementary feeding of twin-bearing ewes approaching lambing with a body condition score of 2.6-3.0 will improve lamb survival and weaning weights.
Lack of effect of regular movement and of mixing groups on the performance of growing pigs
Authors: Greer EB
Published: March 2005

The effect on pig performance of 2 methods to reduce pen stocking densities was examined using 228 pigs growing from 20 to 100 kg in 7 commercial piggeries. Pigs either: (i) remained in the same pen for the full period; (ii) were moved to a different pen every 4 weeks; or (iii) were mixed, after 8 weeks when they weighed about 50 kg, with half the pigs from a second pen and then moved to 2 new pens. Pigs were fed ad libitum the diet normally used on each farm. Daily gain, feed:gain ratio and backfat depth were unaffected by treatment (P> 0.05). There was an indication (P<0.10) that movement increased daily feed intake and this may have been associated with a slight decline in carcass gradings. Fighting occurred when the pigs were mixed after 8 weeks, but no adverse effects were apparent at slaughter. Floor space allowances for growing pigs can be increased by 2 movement strategies (moving or moving-and-mixing) commonly used by producers, with only slight, if any, detriment to performance.
Productivity in the first seven years of a Pinus radiata-annual pasture agroforest in Western Australia
Authors: Anderson GW , Moore RW
Published: March 2005

Pinus radiata seedlings were planted into an annual pasture at low, medium and high densities. The trees were pruned annually from year 4 and those with poor form were progressively culled until final stand densities of 75, 150 and 225 trees ha-1 were achieved 7 years after planting. The pastures were grazed by sheep from year 4. The sheep carrying capacities of the pastures declined as tree density increased because of competition between trees and pasture and also because of debris from thinning and pruning. In year 7, under the high density trees, the sheep carrying capacity of the pastures was 73% and light transmission was 69% of that of control pastures (no trees) and debris covered about 22% of the pasture. Diameter growth measurements from year 5 to 7 were 7.65, 7, 45 and 6.35 cm for low, medium and high density of trees respectively, which indicates that competition between trees had commenced at the high density (P<0.05). There was little conflict between the agricultural and forestry components at the low stand density with satisfactory production from both. This system has the potential to generate annual income to offset pine establishment and silvicultural costs while providing another source of income in the long term. It is being tried on farm scale by some landholders wishing to diversify from grazing-only enterprises.
Recovery of pasture seed ingested by ruminants. 1. Seed of six tropical pasture species fed to cattle, sheep and goats
Authors: Neto M. Simao , Jones R. M. , Ratcliff D.
Published: March 2005

This study examined the effects of different species of ruminants and pasture plants on the passage of ingested seed. Penned cattle, sheep and goats were fed a basal diet of 80% lucerne hay and 20% milled wheat. After 14 days on the basal diet a mixture of known numbers of pasture seeds (Brachiaria decumbens, Axonopus afinis, Neonotonia wightii cv. Tinaroo, Trgfolium semipilosum cv. Safari, Stylosanthes hamata cv. Verano and S. scabra cv. Seca) was fed on 1 day. Faeces were collected for 6 days after feeding the seed while animals remained on the basal diet. Seed samples of each species were tested for germination and hardseededness (or dormancy) both prior to feeding and on seed washed from a subsample of the faeces. Other subsamples were kept moist and emerging seedlings were removed over a 104 week period. Cattle digested less seed than did sheep and goats, but the germination characteristics of the recovered seed were similar for the different animals. The mean recovery of viable seeds ingested was 42, 10 and 19% for cattle, sheep and goats, and 39, 39, 23, 21, 12 and 8% for Safari, Tinaroo, Seca, Axonopus, Brachiaria and Verano. Most of the seeds excreted were recovered on the second and third days following feeding. For sheep and goats, the percentage recovery of ingested legume seed as emerging seedlings was similar to recovery calculated from washing out seed followed by germination testing. However, there was a lower recovery, as seedlings, for the seeds ingested by cattle. This was partially due to the larger number of hard seeds remaining in cattle faeces after the 104 week germination period.
Productivity and persistence of cultivars and Algerian introductions of perennial ryegrass (Lolium perenne L.) in Victoria
Authors: Reed KFM , Cunningham PJ , Barrie JT , Chin JF
Published: March 2005

We assessed the main Australian and New Zealand cultivars and a selection of Algerian introductions of perennial ryegrass at 3 sites in Victoria, 1 of which was irrigated. Seasonal yields of herbage, persistence and the presence of the ryegrass endophyte (Acremonium loliae) were assessed. At Drumborg (dryland), Ellett was the most productive cultivar over 3 years (9.25 t/ha DM total). At the other dryland site, Hamilton, the cumulative yields over 4 years were highest from the cultivars Kangaroo Valley Early (14.57 t/ha DM), Victorian (14.45 t/ha DM) and Ellett (13.80 t/ha DM); lesser yields were obtained from Grasslands Nui (12.92 t/ha DM) and Grasslands Ruanui (1 1.25 t/ha DM). At Numurkah, under irrigation. the yield of 4 cultivars, Ellett (22.14 t/ha DM total), Grasslands Nui, Kangaroo Valley Early and Victorian, were not different (P> 0.05) over 3 years. Differences between cultivars in patterns of growth were occasionally noted, particularly the higher rate of growth of Kangaroo Valley Early in winter. Under irrigation, Ellett and Grasslands Nui sometimes gave higher rates of growth than other cultivars during late spring and summer ( P < 0.05). Seed of 6 accessions from Algeria, which had been produced in Victoria from old plots, was sown for comparison with the commercial cultivars at Hamilton. The accessions grew poorly in the establishment year but later were as productive as the cultivars. Leaf sheaths were examined in year 4, for presence of the ryegrass en,dophyte (Acremonium loliae) in plants surviving the 1982-83 drought. Only plots of Ellett and Victorian contained high proportions of endophyte-infected plants (> 60% of plants infected). Relative to other entries, Ellett maintained a high plant density at all 3 sites. However, at 2 sites, Victorian and Grasslands Nui maintained a similar density to Ellett, and all the Algerian lines sown at Hamilton maintained a similar density to Ellett.
Residual value of superphosphate and Queensland rock phosphate for serradella and clover on very sandy soils as assessed by plant growth and bicarbonate-soluble phosphorus
Authors: Bolland MDA , Gilkes RJ , Allen DG , D'Antuono MF
Published: March 2005

Superphosphate (0-0.4 t/ha P) and Queensland rock phosphate (0-20 t/ha P) were incorporated into the top 10 cm of very sandy soil near Esperance, W.A. The effectiveness of the fertilisers for pastures was calculated from dry herbage yields of yellow serradella, slender serradella and subterranean clover. Soil samples were collected just after fertiliser application and at intervals up to 2.5 years for measurement of bicarbonate-extractable phosphorus (soil test), which was related to plant yield. Results for all 3 species were very similar in response to superphosphate. The effectiveness of superphosphate decreased by about 50% between years 1 and 2, and by a further 25% between years 2 and 3. The effectiveness of Queensland rock phosphate was about 7% that offreshly applied superphosphate in the year of application for all 3 species and for the next 2 years, its effectiveness relative to freshly applied superphosphate remained about constant for yellow serradella and approximately doubled for slender serradella and clover. For superphosphate 2.5 years after application, the amount of phosphorus extracted by the soil test compared with freshly applied superphosphate decreased by about 80%. The soil test extracted a very small proportion of the phosphorus applied as Queensland rock phosphate and the amount extracted decreased by about 50% during 2.5 years. Although the plants responded strongly to increasing levels of applied phosphorus, soil test values remained low until yields of about half the maximum yield were attained. Separate calibration curves were required for each fertiliser and species and each calibration curve was best described by 2 component linear spline functions.
Competition between wheat and brome grass in Western Australia
Authors: Gill GS , Poole ML , Holmes JE
Published: March 2005

Brome grass (Bromus diandrus Roth) has become a serious weed of wheat in Western Australia, particularly on light textured soils. Six field experiments were carried out to investigate competition between brome grass and wheat. Results showed that brome grass is an extremely aggressive weed in wheat. Although the experimental sites varied considerably in soil type, rainfall and other growing conditions the relationship between brome grass and reduction in wheat yield was remarkably consistent across the sites. An exponential model was found to adequately describe yield loss due to competition with brome grass and will be used for extension purposes in Western Australia. An examination of yield contributing characters of wheat suggested that yield loss due to brome grass had been determined before the crop reached the grainfilling stage and such a result diminishes the importance of competition for water in wheat-brome grass mixtures.
Availability of residual fertilizer nitrogen in a Darling Downs black earth in the presence and absence of wheat straw
Authors: Strong WM , Dalal RC , Cooper JE , Saffigna PG
Published: March 2005

Mineralisation and availability of residual fertiliser nitrogen (N) was studied in pots during December-October with and without the addition of straw (0-7.5 t/ha) on a Darling Downs black earth previously cropped with wheat. Soil (0-0.2 m) and straw were collected from field plots in which wheat was grown previously with supplementary irrigation and fertiliser N applied at 0, 100, 200, 300 or 400 kg/ha. At the end of the fallow, in June, there was a net increase in soil mineral N of between 0.7 and 11.1 mg/kg where fertiliser was applied to the preceding crop. The increase represented between 2 and 9% of the original N application and was larger with increasing N application rate and smaller with increasing rate of straw addition. Straw addition caused a substantial decrease in mineral N which was still evident in June and October, 162 and 305 days respectively following straw addition. Soil mineral N decreased linearly at the rate of 5 kg N/t of straw added up to 7.5 t/ha. The net effect of prior N applications on the quantity of N available to wheat plants was equivalent to 10-23% of the quantity of N applied to the preceding crop in the absence of straw and only 4% in the presence of straw. Residual effects of prior N applications on the quantity of N available for wheat plants was generally greater than was evident as soil mineral N in June. During crop growth, additional available N may have been released from the microbial soil N pool, especially where 200 or 400 kg/ha of N had been applied. Straw addition resulted in more microbial biomass throughout the fallow. The larger microbial N pool, however, contained less N than that immobilised due to straw addition. Thus, regardless of prior N application, less N was available to wheat plants in the presence than in the absence of straw of preceding wheat crops.
The role of manganese toxicity in crop yellowing on seasonally waterlogged and strongly acidic soils in north-eastern Victoria
Authors: Sparrow LA , Uren NC
Published: March 2005

Concentrations of exchangeable and easily reducible manganese (Mn) were measured monthly for 3 1 months in acidic soils at 6 sites used for cropping in north-eastern Victoria. Manganese concentrations in shoots of wheat (Triticum aestivum), when present, were also measured. Changes in Mn concentrations in the soils and in wheat plants were related to seasonal conditions and to the occurrence of crop yellowing, a chlorotic and stunting disorder which affects cereals grown in the region. Peaks in the concentration of exchangeable Mn occurred either when the soils were waterlogged for a prolonged period or when they were subjected to extreme heating and drying during summer. Shoot concentrations of up to 1200 mg/kg of Mn were measured for plants growing in waterlogged soils. However, in some cases concentrations less than 400 mg/kg, a concentration not considered harmful, were measured in shoots of wheat growing under waterlogged conditions but which still showed symptoms of severe chlorosis and stunting. In the absence of waterlogging, concentrations of Mn in wheat shoots were usually less than 400 mg/kg. The evidence suggests that Mn toxicity is not the primary cause of crop yellowing in north-eastern Victoria, but Mn toxicity, induced by waterlogging, probably contributes to crop yellowing when waterlogging is severe. Soil acidity did not appear to be high enough to cause Mn toxicity in the absence of waterlogging.
Effect of cultivar and temperature on the coleoptile length and establishment of barley
Authors: Radford BJ
Published: March 2005

Laboratory experiments were conducted to determine the effects of 7 cultivars and 8 constant temperatures on the coleoptile length of barley seedlings grown in darkness. A field experiment was used to determine correlations between laboratory measurements on seed (coleoptile length, germination and weight) and barley establishment after deep sowing (at 80 and 110 mm). Cultivar and temperature both affected coleoptile length. Cultivars in order of coleoptile length were Orge Saida > Prior > Clipper > Schooner, Grimmett >Grit > Lada. Coleoptiles were longest (61-106 mm) at 10-20�C and shortest (28-36 mm) at 35-40�C. The cultivar x temperature interaction was significant (P<0.01), differences in coleoptile length among cultivars being greatest at low temperatures. Laboratory germination gave the best prediction of barley establishment for the sowing depth of 80 mm (adjusted R2 = 0.47), and coleoptile length and seed weight the best predictions for the sowing depth of 110 mm (adjusted R2 = 0.93 and 0.83 respectively). Strategies for improving barley establishment from deep sowings include cultivar selection, seed selection, selection of sowing time to suit seedbed temperatures and the use of seeding machinery which forms furrows directly over rows of deeply sown seed.
The measurement of subcutaneous fat depth on hot beef carcasses with the Hennessy grading probe
Authors: Phillips D , Herrod W , Schafer RJ
Published: March 2005

The left sides of 1118 hot beef carcasses were measured with the Hennessy Grading Probe (HGP) at a site on the rump. Two experienced technicians then measured fat depth at the same site using the cut-and-measure (CM) technique. Only measurements from carcasses where the 2 CM readings were within I mm were used in subsequent analyses (n = 828). Relative to CM, the HGP overestimated and underestimated the fat depth of lean and fat carcasses respectively. A significant (P < 0.001) linear relationship between the HGP and CM readings on the same carcass was demonstrated (r2 = 0.94, r.s.d. = 1.76 mm). The best prediction of CM was obtained when a quadratic HGP term was included (r2=0.94, r.s.d. = 1.72 mm). The HGP, using the regression equation CM = -2.53 + 1.56 (HGP) - 0.008 (HGP)2 is recommended as an alternative to CM for measuring subcutaneous fat depths of beef carcasses.
Effect of chemical removal of grasses from pasture leys on pasture and sheep production
Authors: Thorn CW , Perry MW
Published: March 2005

Pasture production, pasture composition and quality, and liveweight, body condition and wool growth of Merino weaner wethers were monitored over 2 seasons and at 2 stocking rates (4 and 8 sheep/ha) on a mixed annual grass-legume pasture sprayed with propyzamide to control grasses. Propyzamide virtually eliminated annual grasses from the pasture (less than 5 kg/ha of grass dry matter in spring v. 403 kg/ha on untreated pasture in 1981) and this carried over into the second season (61 kg/ha v. 647 kg/ha in spring 1982). Propyzamide treated pastures had less total dry matter (P = 0.05) throughout 1981: however, except for a single sample date, there was no effect of propyzamide on total available pasture in the second season. Increased growth of clover and capeweed compensated for the absence of the grasses. The higher stocking rate reduced available clover, capeweed and total dry matter (P = 0.05) throughout both years. Sheep grazing grass-free pastures had lower liveweights during winter in both years, but made compensatory gains during late spring and summer consistent with the higher quality (1.6 v. 1.07% nitrogen when sampled in January) of propyzamide treated pastures. In 198 1, wool growth rates were reduced at the higher stocking rate and total clean wool production was reduced from 4.55 kg/sheep at 4/ha to 3.65 kg/sheep at 8/ha. Pasture treatment had no effect on wool production in either year. The implications of using selective herbicides to remove the annual grass component of legume-based annual pastures in south-western Australia are dis cussed in relation to pasture and sheep production.
Reclamation of a saline/sodic soil by aquifer pumping, application of tillage and gypsum and reuse of saline groundwater
Authors: Mehanni AH
Published: March 2005

In the Goulburn Valley, at a site near Tongala, Vic., shallow perched watertables receded from 18 to 135 cm below the surface and the piezometric pressure was reduced from 16 to 180 cm below the surface in a saline/sodic soil 3 months from the start of pumping. Consequently soil salinity was reduced from ECe 12.3 to 7.3 dS/m in the top 30 cm under 1 15 mm ofrainfall. Further reduction in salinity to ECe 3 dS/m was achieved after 19 months. The presence of electrolytes in irrigation water preserved soil permeability during the irrigation season, while gypsum was beneficial during the winter rainfall season. Perennial pasture was established 11 months after pumping commenced. Weeds that originally dominated the site disappeared, while clover produced 70% of total dry matter.
An evaluation of three aerial pasture development methods on the Northern Tablelands of New South Wales, in terms of herbage on offer, botanical composition and animal performance
Authors: Dowling PM , Robinson GG , Murison RD
Published: March 2005

Herbage mass on offer, botanical composition and livestock production of sheep grazing 3 types of pastures developed by 'aerial' methods at 3 stocking rates (5, 7.5 and 10 sheep/ha) were compared in a 3-year grazing trial at Glen Innes, N.S.W., during 1972-75. The pastures were: resident grass-white clover (F), resident pasture plus surface sown grass (SF), and as for SF but with herbicide application prior to surface sowing ofgrass (HSF). All pasture treatments had equivalent rates of superphosphate applied. The sowing effect and the herbicide effect were statistically analysed by contrasting the pasture treatments: SF-F, HSF-SF, respectively. The SF-F contrast showed that herbage on offer of the sown grasses on the SF pasture was greater, and this difference increased with time. Legume herbage on offer was greater on the SF pasture though it declined with time, and exhibited seasonal variation. The HSF-SF contrast indicated that herbage on offer: of sown grass was greater on the HSF pasture and increased with time; of the herbs component was greater on the HSF pasture during the initial and final stages of the experiment; oflegume was greater on the HSF pasture but the difference declined with time; of resident grass was greater on the SF pasture but the difference declined with time; and of dead material was consistently greater on the SF pasture. The contrasts for the resident grasses and dead material components varied seasonally. Herbage on offer of all pasture components declined as stocking rate was increased. Patterns of decline varied with pasture component and pasture treatment. Mean sheep liveweights were influenced by pasture treatment, with sheep on the HSF pasture being the heaviest, and those on the F pasture, the lightest. Increasing stocking rate decreased mean sheep liveweights on pastures F and SF but increased mean sheep liveweights on the HSF pasture. Liveweight declines were least for sheep grazing the F and SF pastures and liveweight increases were greatest on the HSF pasture during late summer-autumn. Greasy wool production per sheep was greatest on the HSF pasture during 1972-73 but thereafter there were no significant differences between treatments. We conclude that, although animal production was increased by the introduction of sown grasses in the short term, the level of superiority was not as great as expected. Changes in management strategies may be required if the greater production achieved is to be sustained.
Simple tests for the assessment of aluminium and manganese levels in acid soils
Authors: Bromfield SM
Published: March 2005

Alkaline formaldoxime and a reagent mixture based on pyrocatechol violet in ammonium acetate were found to be the best of several reagents tested for ranking the concentrations of manganese (Mn) and aluminium (Al), respectively, in solutions absorbed by filter paper strips. The concentrations of these metals in soil suspensions, 1:1 (vh) in 0.01 mol L-1 calcium chloride, were estimated by obtaining clean samples on test strips of filter paper and visually comparing the colours produced with the above reagents against those formed using standard solutions of known Mn and Al concentrations. The test values when compared with analytical values for the filtered suspensions showed that acid soils can be readily ranked into groups. Each group is defined by a given range of Mn or Al levels. The reagents, sampling procedure and colour development have many advantages suited to a field test for characterising the A1 and Mn levels of acid soils.