bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of temperature on seed set and in vitro pollen germination in French beans (Phaseolus vulgaris)
Authors: Farlow PJ , Byth DE , Kruger NS
Published: March 2005

A technique for in vitro germination of French bean pollen was developed and the effect of temperature on gamete development, pollen germination and seed set investigated. Temperature had a profound effect on in vitro pollen germination percentage, pollen tube growth and bursting percentage. These were maximal at 7.2�C, 16.7�C and 38.3�C, respectively. In this study, pollen development was not affected at day/night temperatures of 16.1�/12.8�C, and ovule abortion was the cause of seed set failure at these temperatures. Hot water treatment (48�-44�C) of flowers caused failure of seed set due to pollen inviability. Consequently this technique may allow hybridization without emasculation in beans. Treatment of buds with hot water of different temperatures and in vitro pollen germination at high temperatures may have application as screening techniques for heat tolerance in French beans.
Recovery of nitrogen by wheat from various depths in a cracking clay soil
Authors: Strong WM , Cooper JE
Published: March 2005

The ability of wheat to recover nitrogen from topsoil and subsoil was studied in two experiments on the Darling Downs, Queensland. Nitrate was placed at the required depth by injecting solution at regular intervals over a small plot (<1 m2) on soil almost depleted of mineral nitrogen to a depth of 120 cm. In experiment 1 a lower grain yield with shallow (7.5 cm) compared with deep (30, 60, or 90 cm) placement was partly attributed to a temporary nitrogen deficiency induced by a 26-day drought around heading. The interaction between moisture regime and nitrogen placement depth was further studied in experiment 2. The absence of any useful falls of rain during the first 78 days of crop growth induced a temporary deficiency of nitrogen with topsoil placement (7.5 cm). Deficiency was rapidly relieved by rain (74 mm) between boot and flowering and the difference in nitrogen uptake between topsoil and subsoil placements had disappeared at flowering. Two irrigations each of 36 mm were sufficient to avert early nitrogen deficiency, almost doubling (57 kg ha-1 to 108 kg ha-1) the uptake of nitrogen at boot. In contrast, drought during early crop growth caused a negligible reduction in the uptake of subsoil (45 cm or 90 cm) placed nitrogen. Soil mineral-nitrogen or fertilizer nitrogen that is leached into the subsoil should provide a more satisfactory reserve of available nitrogen than fertilizer applied to topsoil at planting, for winter cereal crops in Queensland.
Surveys of speckled leaf blotch and other foliar diseases of wheat in Victoria, 1974 to 1978
Authors: Brown JS , Paddick RG
Published: March 2005

The severity of speckled leaf blotch (Mycosphaerella graminicola (Fuckel) Schroeter, Septoria tritici Rob. ex Desm.) in wheat crops was surveyed in the Wimmera during the 1974-77 seasons and in all the major wheat growing areas of Victoria in 1978. Speckled leaf blotch was found in all crops and the severity varied greatly within and between seasons. The average percentage of affected area on the penultimate leaf of main tillers was 24%, 28%, 1.5%, 0% and 9.4%, respectively, for the successive seasons. The corresponding grain yield losses were estimated at 19, 21, 5, 0 and 12% by using an experimentally derived relation between yield loss and disease severity. In 1978, glume blotch (Leptosphaeria nodorum (Miiller, Septoria nodorum (Berk.) Berk.), stem rust (Puccinia graminis Pers. f sp. tritici Erikss and Henn.), leaf rust (Puccinia recondita Rob. ex Desm. f sp, tritici Erikss) and powdery mildew (Erysiphe graminis DC. f sp. tritici E. Marchal) occurred in 8%, 3%, 1% and 0.5%, respectively, of the crops sampled. These surveys have shown speckled leaf blotch to be the most important foliar disease of wheat in Victoria.
The effect of aerated steam on six seed-borne pathogens
Authors: Navaratnam SJ , Shuttleworth D , Wallace D
Published: March 2005

The effect of aerated steam on six seed-borne pathogens was investigated. Complete eradication was obtained for Septoria apiicola in celery seed, Fusarium monilfiorme in sweet corn seed, Corynebacterium michiganense in tomato seed and Xanthomonas campestris in cauliflower seed. Septoria nodorum in wheat seed was partially controlled. Xanthomonas malvacearum in cotton seed was not controlled even at the highest temperature tested.
Sealing a farm silo for insect control by nitrogen swamping or fumigation
Authors: Williams P , Minett W , Navarro S , Amos TG
Published: March 2005

A bolted galvanized iron silo (21.5 t) was sealed using a polyvinyl resin formulation (1624 White) sprayed onto joints from the inside. Gastightness was assessed by pressure decay and static pressure tests. The silo was loaded with wheat into which cages of insect-infested wheat, thermocouples and gas sampling lines, were introduced. Oxygen levels were reduced to < 1 % by purging with nitrogen, and similar levels were then maintained by a slow nitrogen bleed for 35 days, after which the silo was emptied. All adult insects were dead but, as expected, some immatures survived since the maintenance period was too short to ensure complete kill at the observed grain temperatures (generally < 15�C). The silo was reloaded, resealed and tested again for leaks. Some leaks were found and sealed with silicon rubber. Gastightness was not as good as before, though the silo would still be suitable for fumigation. Further sealing would be required however, if nitrogen were to be used efficiently (maintenance rate of 0.2 m3 t-1 day-1). Sealing achieved was sufficient to permit use of nitrogen or fumigants but sealants cost $132 and labour a minimum of $280, representing an overall cost of $19.1 6 t-1. This would still be cheaper than buying a new silo of suitably gastight construction at a cost of at least $28 t-1.
An evaluation of some methods of predicting muscle weight of cattle
Authors: Murray DM
Published: March 2005

The accuracy of some published equations to predict side muscle weight of cattle was assessed by fitting data from cattle of known carcase composition to them. A method of comparing the accuracy of different prediction equations is also described. The results indicated that there was considerable variation between the prediction equations in the accuracy with which they predicted side muscle weight in the test data. This suggests that such prediction equations should be applied to independent sets of data with extreme caution.
Toxicological investigations on Astragalus hamosus and Astragalus sesameus
Authors: Williams MC
Published: March 2005

Astragalus hamosus L. and Astragalus sesameus L. were examined for the presence and type of aliphatic nitro compounds and for their toxicity to 1 -week-old chicks. A. hamosus leaves assayed 10 to 11 mg of NO2 g-1 in compounds that yielded 3-nitropropionic acid upon hydrolysis. Water extracts of A. hamosus leaves were toxic to chicks at the equivalent of 3 g of dried plant per chick, and lethal at 6 to 8 g. A. sesameus did not contain nitro compounds and was non-toxic to chicks.
The influence of water stress on nitrogen and phosphorus uptake and concentrations in Townsville stylo (Stylosanthes humilis)
Authors: Fisher MJ
Published: March 2005

The phosphorus concentrations of Townsville stylo (TS) grown in the Northern Territory are lower than in Queensland, and fall below the requirements of grazing cattle for much of the year. An explanation was sought by measuring N and P in swards subjected to water stress at various times during growth. Stresses during early vegetative (EV), late vegetative (LV) and flowering (F) stages were compared with a well watered control. While nitrogen concentrations were affected little, water stress greatly reduced phosphorus concentrations, the relative effects being EV > LV > F. The EV stress depressed phosphorus concentration to 0.08% compared with 0.20% in the control. Phosphorus level recovered on the relief of stress to the same level as the control. Phosphorus concentration in stems was more sensitive to stress than that in leaves. These results show that if chemical analysis of plants is to be used to indicate the phosphorus status of the soil, the analyses will be unreliable unless the plants have grown without water stress for at least six weeks.
Plant productivity and persistence in mixed pastures containing lucerne at a range of densities with subterranean clover or phalaris
Authors: Wolfe EC , Southwood OR
Published: March 2005

Lucerne (Medicago sativa cv. Hunter River) was sown at three densities (rows spaced 17.5, 35 and 52.5 cm apart) in factorial combination with each of three cultivars of subterranean clover (Trifolium subterraneum cw. Geraldton, Seaton Park and Woogenellup) and two of phalaris (a summer-dormant selection of P. aquatics, and a P. aquatica-P. arundinacea hybrid). All three clover cultivars were included in the lucerne-phalaris swards. After the establishment year, plant productivity and persistence in these mixtures were assessed under rotational grazing over the next three years. Lucerne density had little effect on the total seasonal or annual productivity of the swards. Lucerne grew and survived best with Geraldton clover and worst with the phalaris hybrid; total pasture yields reflected these differences in summer (two occasions) or autumn (one occasion) when lucerne was the dominant component. In winter, when lucerne grew slowly, the cultivar of clover was an important factor influencing total production. A mixed sward of lucerne and Seaton Park clover grew as well as or better than the other mixtures in winter, and occasionally in summer-autumn it was more productive than lucerne-phalaris, Seaton Park persisted with lucerne better than did any other companion plant.
The frequency of Cryptolestes spp. in grain in south-east Queensland
Authors: Sinclair ER , Bengston M
Published: March 2005

In a survey of 60 grain farms on the Darling Downs, Queensland, during 1977-78, the flat grain beetles Cryptolestes spp., which are germ feeders in stored grains, were found on 39 of the farms and in 15% of the 483 samples taken. Ninety percent of infestations involving Cryptolestes spp. were found in bag or bulk stores of seed and feed grain, where they were usually associated with heavy infestations of the three more common stored grain pests, the rice weevil Sitophilus oryzae (L.), the lesser grain borer Rhyzopertha dominica (F.), and the red flour beetle Tribolium castaneum (Herbest.). Three species of Cryptolestes were detected: C. pusillus (Schonherr) (45.6% of farms surveyed), C. ferrugineus (Steph.) (28.1 %), and C. pusilloides (Steel and Howe) (15.8%). During the farm survey, samples were also collected from 8 of the 11 central storages reported infested with Cryptolestes spp. C. ferrugineus was present in each of these samples, C. pusillus in only one, whilst C. pusilloides was not found. The three species were tested for resistance to malathion and fenitrothion, the most commonly used grain-protectant chemicals, by exposing adults to treated wheat. C. pusillus and C. pusilloides were susceptible to both malathion and fenitrothion (LC99.9 < 1 mg kg-1). C. ferrugineus, whilst susceptible to fenitrothion (LC99.9 < 1 mg kg-1) was resistant to malathion, with LC99.9 of 300-400 mg kg-1 compared with the recommended dose of 18 mg kg -1. Although C. pusillus was the most common species on farms, it was concluded that C. ferrugineus was the most important overall because it is biologically better suited to the grain in central storages, which is typically hot (>30�C) and of low moisture content (< 12% for wheat).
Use of flesh firmness and other objective tests to determine consumer acceptability of Delicious apples
Authors: Wills RBH , Bambridge PA , Scott KJ
Published: March 2005

Delicious apples were stored at four temperatures from 0�C to 20�C to produce fruit at different stages of deterioration. At regular intervals, the texture, flavour, and overall quality were assessed by a taste panel, and the flesh firmness, titratable acidity, soluble solids and starch content were measured. It was found that changes in flavour, texture and overall quality were highly correlated and that acceptability of fruit held at higher temperatures declined at a faster rate. During storage there was a decrease in flesh firmness and titratable acidity that was highly correlated with flavour, texture and overall quality. The use of either measurement would seem to be suitable to assess whether fruit were of a sufficiently high quality to warrant marketing. Soluble solids increased during storage but tended to stabilize at a maximum level of about 14%. Starch content decreased during storage to a level where it was undetected by the iodine test. Neither measurement appeared suitable to grade fruit for marketing.
Post-weaning growth and carcase characteristics of Chianina, Brahman and Hereford cross, and Hereford steers in southern Queensland
Authors: Strachan RT , Peart WJ , Coleman RG , O'Rourke PK
Published: March 2005

The post-weaning growth of 281 Chianina x Hereford (CC.HH), Chianina x (Brahman x Hereford) (CC.BH), Brahman x Hereford (BB.H H), Hereford x (Brahman x Hereford) (H H.BH) and Hereford (HH.HH) steers grazing improved brigalow (Acacia harpophylla) country on a commercial property in southern Queensland was studied over 3 years. Representative animals were slaughtered at mean ages of about 880 and 1000 days and carcase characteristics examined. From weaning to 860 days of age, the CC.HH and CC.BH steers gained at a faster rate than the BB.HH steers, which in turn, grew faster than the HH.BH and HH.HH steers. Their growth rates were 0.58, 0.57, 0.55, 0.50 and 0.49 kg day-1, respectively. The CC.HH and the CC.BH steers dressed 309 kg with 6.5 mm fat and 308 kg with 7.0 mm fat, respectively. They were heavier (P< 0.05) and longer carcases with less fat and with larger eye muscle areas, than the other genotypes. The BB.HH and HH.BH carcases were intermediate, in terms of weight, being 291 kg and 278 kg, respectively, while the HH.HH carcases were lighter (P< 0.05) at 260 kg. The HH.HH carcases had similar fat cover to the HH.BH carcases, 9.6 mm vs 10.2 mm, and both had less fat cover than the BB.HH with 11.6 mm fat. Using the Australian Beef Carcases Appraisal System, the CC.HH and CC.BH carcases scored more points (P< 0.05) than all other genotypes.
Nutrient problems in sown pasture on an acid soil. I. Survey of the problems and suggested corrective treatments
Authors: McLachlan KD
Published: March 2005

A systematic study was made of nutrient problems associated with regression in the productivity of sown pasture on an acid soil on the Southern Tableland, NSW. Soil deficiencies of calcium, magnesium, nitrogen, phosphorus, sulphur, potassium, molybdenum, boron and possibly zinc, were demonstrated, and the first report of copper deficiency on a highland soil is recorded. A pH effect was also involved. The remedial fertilizer treatments developed, increased pasture productivity to a level approaching average yields for Southern Tableland soils. The findings are also relevant to horticultural and forest production in the area, and could be useful in regeneration of native species on these soils in National Parks.
Response of nine soybean lines to soil moisture conditions close to saturation
Authors: Hunter MN , Jabrun PLMde , Byth DE
Published: March 2005

The effects of two constant water table treatments, maintained at 3 and 15 cm below the soil surface (CWT 3 and CWT 15, respectively), were compared with the effect of overhead irrigation (OHI) on dry matter production of nine soybean (Glycine max) lines, grown for 36 days in beds of soil in the glasshouse. The lines represented a range of maturity groups. Water for each irrigation treatment was supplied with, or without, dissolved inorganic nitrogen (100 ppm N), on a split plot basis. CWT 15 plants accumulated 37% more dry matter, and 35 times more nodule dry matter, than did OH1 plants. CWT 3 plants became very chlorotic within a week of imposing the water table, but recovered to produce only 18% less dry matter than the OHI plants. CWT 3 plants accumulated the greatest amount of nodule dry matter, and this fraction accounted for 5% of total plant dry weight in some lines. Plants in both of the water table regimes were taller than the OHI plants, even for lines that flowered in 21 days, and this effect reduced the cultural disadvantage of short stature normally noted in early flowering lines. Nitrogen application marginally increased shoot proportion, plant height and node number, but decreased nodule mass in CWT 15 and OHI plants. The study indicated that soybeans can respond well to permanent water tables maintained close to the soil surface, and attain rapid early growth independent of applied nitrogen. Projections suggest that high yields of seed are feasible in 80-85 day soybean crops growing on a controlled water table system. This system also may promote other operational efficiencies related to a shortened cropping cycle, simplified water management, and weed control.
Effects of mineral supplementation on the performance of steers grazing birdwood grass (Cenchrus setiger) pastures in north Western Australia
Authors: Holm AM , Payne AL
Published: March 2005

The liveweight of Shorthorn steers on fertilized birdwood grass (Cenchrus setiger) pastures, growing on sandy 'Pindan' soils, at Derby, north Western Australia, was recorded over 3 years from September 1973 to July 1976. A separate draft of steers was used in each of the 3 years. Half of the steers in each draft were given a supplement of urea, phosphoric acid and ammonium sulphate in the drinking water. These supplemented steers gained an average of 147 kg, 128 kg and 93 kg per head, or 31 kg, 70 kg and 44 kg per head more, than unsupplemented steers in the 3 years. There was a consistent positive response in liveweight gains in all post-wet and pre-wet season periods, and a positive response in two of the three wet seasons. Two levels of pasture use were also imposed but did not have any consistent effect on pasture composition or liveweight gain. Copper injections, and cobalt as cobalt oxide bullets, were given to approximately half the stock in years 1 and 2 respectively. There was a small response (P < 0.05) to copper during the post-wet season, but over the whole grazing period the response was negligible. The cobalt bullets had no effect.
Fungicide seed dressings: their effects on emergence of soybean and nodulation of pea and soybean
Authors: Stovold GE , Evans J
Published: March 2005

A range of fungicides was tested for their efficacy as seed treatments for the control of seedling diseases of soybeans. Thiram, captan and captafol at rates of 2000 ppm a.i. w/w or 3000 ppm a.i. w/w provided the most consistent protection in field trials conducted for 3 years at three separate sites. Of these three fungicides, thiram had the least effect on nodulation by Rhizobium applied to the seed, but an inhibiting effect did occur in some years. Several other fungicides had little effect on nodulation but were inconsistent in controlling seedling diseases. In a glasshouse pot trial, the fungicides did not reduce nodulation even though some were consistently toxic in the field experiments. In field trials with peas and soybeans, the inhibitory effect of a toxic fungicide (captan) on nodulation by seed-borne Rhizobium was avoided by using alternative methods of inoculation which separated Rhizobium from the treated seed. A water suspension of peat-based rhizobial inoculant, or sand particles coated with peat inoculant introduced to the furrow together with the seed, were effective methods of inoculation. A large-particle inoculant carrier (heat-killed soybean seed) was unsuitable. For control of soybean seedling disease we recommend the use of thiram fungicide at a rate of 2000 ppm a.i. w/w, and where practicable the use of alternative methods of Rhizobium inoculation to separate the inoculum from the treated seed.
The effects of stocking rate and nitrogen fertilizer on the productivity of irrigated perennial pasture grazed by dairy cows. 2. Animal production
Authors: King KR , Stockdale CR
Published: March 2005

The relation between the stocking rate of dairy cows and their production from irrigated perennial pasture, with and without nitrogen (N) fertilizer, was studied over 2 years at Kyabram, Victoria. Pastures were rotationally grazed at stocking rates ranging from 4.4 to 8.6 cows ha-1. In each year, N treatments were topdressed four times at a rate of 56 kg N ha-1. For every additional cow per ha, production per ha decreased by 260 and 329 kg of milk, 12.3 and 15.5 kg of butterfat, and 10.7 and 14.5 kg of protein for years 1 and 2, respectively. In year one, the highest production of milk and butterfat (17,900 and 847 kg ha-1, respectively) was from cows stocked at 8.6 cows ha-1, and for protein (597 kg ha-1) from 7.6 cows ha-1. In year 2, production per ha of all milk products maximized and then declined. Maximum production of milk and butterfat (14,180 and 675 kg ha-1, respectively) was at 6.6 cows ha-1, and protein (508 kg ha-1) at 5.9 cows ha-1. Increasing stocking rate also reduced the liveweight of cows at all times. Topdressing with N fertilizer had no effect on total milk or butterfat production per cow, but consistently increased protein production. The range in response increased from 2 to 7 kg protein per cow at 4.4 and 8.6 cows ha-1, respectively. Application of N fertilizer increased liveweight per cow, with greater increases occurring at high stocking rates. In year 2, the efficiency of butterfat production over the whole year was 29.9, 29.3 and 37.0 kg of DM (pasture and supplements) per kg of butterfat produced for 4.4, 6.6 and 8.6 cows ha-1, respectively.
Tolerance of perennating Stylosanthes plants to fire
Authors: Gardener CJ
Published: March 2005

The resistance of sixteen Stylosanthes spp. accessions to fire was studied in the dry tropics of north Queensland. Perennating plants were subjected to one of five burns of varying temperature. Fire temperatures at the soil surface were measured with heat-sensitive crayons. Fires with intermediate temperatures provided the best discrimination within and between species. Only one line,S. guianensis cv. Schofield, failed to survive the coolest fire. Only S. scabra cv. Seca and S. viscosa CPI 38611 survived the hottest burn. Generally, lines of S. scabra and S. viscosa were fireresistant and S. guianensis more susceptible. However, within a species there were large and consistent differences in reaction: e.g. one S. viscosa line, CPI 34904, proved highly susceptible to fire. All new shoots on the six lines surviving a hot fire grew from 14-38 mm below ground level. In some, the shoots had clearly grown from root tissue. After burning twice, both perennial plants and seedlings were absent in five lines although some seed remained in the soil. The implications of these findings in the potential use of Stylosanthes spp, are discussed.
Effects of water deficit on yield of wheat and triticale
Authors: Sutton BG , Dubbelde EA
Published: March 2005

The yield response of two commercial bread wheat cultivars and one triticale to water deficits imposed before anthesis, after anthesis, or during the complete life cycle was studied in a large bin (55l) experiment under rain shelters at Camden, New South Wales. Water status was managed by weekly water replacement to allow withdrawal to 25 and 0% remaining available soil water for the well-watered and deficient treatments, respectively. The three cereals performed similarly under continuously well-watered conditions (89.9, 91.1, and 100.7 g grain/bin) but under continuous water deficit the triticale produced significantly less than the bread wheats (31.2 cf 53.1 g grain/bin), respectively. The reason for this was the greatly reduced yield per plant from tillers in the triticale. Efficiency of water use over the complete life cycle for grain production was greater for the wheats than for the triticale (1.351 cf 0.954 g l-1, respectively), and maximum efficiency resulted from provision of adequate water before anthesis (an average of 1.310 g l-1 for treatments well watered before anthesis, cf an average of 1.130 g l-1 for those growing under water deficits). Post-anthesis water status had no significant effect on these values.
Effects of initial watering on nodulation of lupins
Authors: Philpotts HR
Published: March 2005

The need for free water movement through the soil after sowing to obtain good nodulation of yellow lupins (Lupinus luteus) was verified in a glasshouse experiment. Withholding overhead watering after sowing reduced the number of plants nodulated by approximately 30% when compared with surface watering at either one or 3 days after sowing. The amount of nodule tissue of nodulated plants was also lowered. Lime pelleting or a higher rate of inoculation increased the number of plants nodulated, but did not increase the amount of nodule tissue on nodulated plants. With watering 3 days after sowing, fewer plants nodulated and they had less nodule tissue than with watering after one day, unless lime-pelleted seed was used or (in the case of number of plants nodulated) a higher rate of inoculum was used.
A method for advanced stage evaluation of pasture species: a case study with bred lines of Macroptilium atropurpureum
Authors: Jones RM , Jones RJ , Hutton EM
Published: March 2005

A method is described for evaluating persistence and productivity of pasture species in the advanced stage of testing. Six bred lines of Macroptilium atropurpureum were compared with cv. Siratro at Samford, south-east Queensland, under stocking rates equivalent to 2.0 and 3.0 steers-ha-1. Each plot was grazed separately for 4 days every 6 weeks, without any mowing being imposed. Attributes measured over a 5-year period included presentation yield, legume density, weed invasion and soil seed reserves. One line of M. atropurpureum was superior to Siratro in yield and plant density, although it produced lower reserves of soil seed. These results were similar to those from a previous experiment under cutting. The advantages and limitations of the method are discussed.
Effectiveness of soil dressings and foliar sprays of copper sulphate in correcting copper deficiency of wheat (Triticum aestivum) in Queensland
Authors: Grundon NJ
Published: March 2005

One field and two glasshouse trials were conducted to test the effectiveness of soil and foliar applications of copper sulphate in correcting copper deficiency of wheat on a severely deficient, nearneutral clay soil in the Western Downs region of Queensland. In the field, when wheat was stressed for water from late tillering (Feekes stage 5) to anthesis (Feekes stage 11) , soil dressings of 2.5-10.0 kg CuSO4.5H2O ha-1 increased early vegetative growth but foliar symptoms of copper deficiency reappeared during stem elongation, and grain yields were negligible at all rates. A single foliar spray of 2% CuSO4.5H2O applied at mid-tillering (Feekes stage 3) also did not correct the deficiency completely: foliar symptoms reappeared and grain yield was low (141 kg ha-1). A double spray treatment, the first applied at mid-tillering and the second just before booting (Feekes stage 10), was more effective and resulted in a grain yield of 800 kg ha-1. In a glasshouse experiment supplied with adequate water, a soil dressing equivalent to 16 kg CuSO4.5H2O ha-1 (3.2 mg Culpot) completely corrected the deficiency. In a second glasshouse experiment, 2% CuSO4.5H2O solution was applied as single sprays at Feekes stages 3, 8, 9, 10 or 11, or as double sprays at Feekes stages 3 + 8, 3 + 9, 3 + 10 or 3 + 11. The most effective single spray was that applied at Feekes stage 10, but maximum dry matter and grain yield were obtained when a double spray was applied at Feekes stage 3 + 10. The effectiveness of soil and foliar applications of CuSO4.5H2O for correcting Cu deficiency of dryland wheat in Queensland soils are discussed in relation to water regime and supplying adequate Cu for both vegetative and reproductive growth.
Mineral nitrogen in soils undergoing irrigated rice-upland crop rotations
Authors: Willett IR , Higgins ML
Published: March 2005

Surface soil (0-150 mm) mineral nitrogen levels were monitored in field plots undergoing rice-wheat-wheat and rice-fallow rotations to study the effects of rice growing on the mineral nitrogen content of soils for subsequent crops. Ammonium nitrogen accumulated in the soils during the first 3 weeks of flooding of the rice crop, reaching 54 mg N kg-1 in a grey clay, and 23 mg N kg-1 in a transitional red-brown earth. Thereafter, ammonium nitrogen decreased so that at the time of drainage the soils contained between 2 and 6 mg N kg-1. Nitrate levels during the flooding period fluctuated between 1 and 7 mg N kg-1. In each subsequent fallowing period, nitrate levels increased so that there was approximately 20 mg N kg-1 as nitrate present during the early growth stages of the post-rice crops. However, at the harvests of each post-rice crop, nitrate nitrogen levels had decreased to between 1 and 7 mg N kg-'. Fluctuations in nitrate levels were interpreted in terms of gains from mineralization and nitrification and losses by crop uptake, although leaching and denitrification during periods of heavy rainfall or irrigations could not be assessed. Ammonium levels in the post-rice period increased in the months of October and November when fallowed, but other fluctuations showed no consistent trends. Nitrite levels were low (< 0.6 mg N kg-1) throughout the experiments. Total mineral nitrogen levels during the early growth stages of the crops grown after the rice corresponded to between 31 and 95 kg N ha-1 in the surface 0-150 mm of soil. It was concluded that in the rotations studied, lowland rice cropping did not lead to depletion of mineral nitrogen to such an extent that it could be implicated as a factor in the poor growth of upland crops grown in rotation with lowland rice.
The control of breakdown of potato seed pieces with fungicidal dusts
Authors: Hughes IK
Published: March 2005

The breakdown of potato planting material is a serious problem in southern Queensland, particularly where cut seedpieces are used. Some growers use captan (50 g kg-1) or zineb (40 to 200 g kg-1) dusts to reduce losses, but the values of these treatments have not been accurately assessed. A number of chemicals were compared with a standard zineb (80 g kg-1) treatment and no treatment under field conditions. While zineb significantly reduced breakdown in four of eight experiments, mancozeb at equivalent concentration was significantly better in three of four experiments. Mancozeb at 400 g kg-1 was significantly better again than the lower concentration. The 400 g kg-1 concentration of mancozeb was evaluated on three seed consignments for effect on plant stand and yield. The number of plants that emerged was increased by 29%, with a 34% increase in yield. The increase in yield over what could be expected from improved numbers of plants is attributed to the control of wilt diseases and prevention of early crop senescence, which followed the prevention of basal stem rot by retention of seedpieces.
Control of premature fruit drop in Macadamia integrifolia: effects of naphthalene acetic acid application, cincturing, and shoot-tip removal
Authors: Williams RR
Published: March 2005

The effects of NAA application, cincturing and shoot-tip removal on the incidence of premature fruit drop were investigated in orchard-grown trees of Macadamia integrifolia cv. Kakea. A single, post-anthesis application of NAA (1 ppm) increased (P < 0.05) the final set of macadamia fruit by 35%. Limb cincturing combined with shoot-tip removal increased (P < 0.05) initial fruit set and possibly final set. Cincturing alone was less effective and shoot-tip removal had no effect alone.
The accuracy of visual assessments for weight in young beef calves
Authors: Morris CA , Smith RJ , Hearnshaw H , Dicker RW
Published: March 2005

A trial was carried out to estimate how accurately calves sorted into classes by sex, breed and nutritional background can be placed into one of three sub-classes by visual assessment. Eight recorders independently assessed each group twice in August when calves were a month old, and six recorders repeated the exercise 4 months later. Calves were visually assessed first for liveweight, as if they were potential breeding stock ('weight assessment'), and secondly for whatever criteria the recorders might use for potential breeding stock for sale in their own herds ('stud assessment'). The objective was to simulate two possible forms of visual assessment in a bull breeder's herd, with the actual weight records being used here for comparison. Both visual assessments were compared additionally with weight records adjusted for calf age and dam age. The results were expressed in terms of the weight difference (W1) of animals visually classed by the recorder into the top vs bottom third of a group, compared with the weight difference (W2) attainable by using objective measurement at the same age, i.e. 100x W1/W2. Where the standard was unadjusted weight, then W2 in August was 31.6 kg overall. In the stud assessment recorders found that calves in the top vs bottom third differed by 17.4 kg, and by 18.4 kg in the weight assessment, equivalent respectively to 55% and 58% of the possible selection pressure attainable. Comparing only weight assessments against August weights which were adjusted for calf age and dam age, 48% of the potential selection pressure was attainable. In the December assessments, recorders were randomly allocated to first making stud assessments followed by weight assessments, or vice versa. Subsequent analysis showed that the sequence was not important. Compared with December liveweights adjusted for calf age and dam age, the selection intensities attainable by stud and weight assessment were 41 and 48%, respectively. The implications of these findings for the Australian beef bull breeding industry are discussed.
Embryo survival in relation to number and site of ovulations in the ewe
Authors: White DH , Rizzoli DJ , Cumming IA
Published: March 2005

The incidence of single-ovulating, and bilateral and unilateral twin-ovulating ewes was determined for 12 flocks that included three breeds of sheep; these were observed at four times within a year. Twin ovulations among these breeding ewes had approximately equal probabilities of being unilateral or bilateral. This suggests that ovulation rate is unlikely to be determined from within the ovary itself. An examination of several sets of published data revealed that the probabilities of embryo survival are consistently highest for single-ovulatory ewes and least for unilateral twin-ovulators. The higher level of embryo losses in unilateral twin-ovulating ewes may be associated with a high incidence of transuterine migration by embryos in these ewes. The probability of successful migration varied with breed and time of year. A binomial model is postulated which takes account of these different probabilities of embryo survival. The model fitted three out of five sets of data examined; the other two sets indicated homeostatic and ewe effects, respectively, acting on embryo survival.
Sexual behaviour and semen characteristics of boars: effects of high temperature
Authors: Winfield CG , Hemsworth PH , Galloway DB , Makin AW
Published: March 2005

The effect of 4,7 or 10-day periods of high air temperatures on the sexual behaviour and semen characteristics of mature Large White crossbred boars was determined in three experiments. In experiment 1, boars kept at 40�C for 8 hours and 30�C for 16 hours each day for 7 days had lower courting behaviour activity when tested at 40�C than control boars tested at <25�C. After similar heat treatment in experiment 2, boars tested at 30�C showed no significant differences in courting or copulatory behaviour from control boars, but the semen of two of six treated boars showed evidence of severe testicular- epididymal dysfunction. The semen of a third treated boar showed evidence of moderate testicular-epididymal dysfunction. In experiment 3, four boars were given a similar daily high temperature cycle to the above, either for 4 or 10 days. Two of the four boars given high temperatures for 10 days had semen with signs of severe testicular-epididymal dysfunction. The semen of the other two boars in this group, and one boar treated for 4 days, showed evidence of moderate dysfunction. It was concluded that during hot weather boars will mate normally during the cooler part of the day, and that they are able to tolerate short periods of heat stress (< 4 days) without detriment to semen characteristics. Protection from longer periods of high temperatures ( > 7 days) is necessary.
Tannins in pasture legumes. 2. The annual and perennial Medicago species
Authors: Marshall DR , Broue P , Grace J , Munday J
Published: March 2005

A total of 557 accessions representing 35 species of annual and perennial medics were tested for the presence of tannins in their leaves and mature seed coats. None of the lines tested produced tannins in their leaves, while all produced tannins in their seed coats. The implications of these findings are discussed in relation to the development of bloat-resistant lucerne varieties by plant breeding.
Comparison of lucernes when grown on a heavy clay soil infected by Phytophthora, and their response to attack by the spotted alfalfa aphid (Therioaphis trifolii f. maculata)
Authors: Rogers VE
Published: March 2005

Eighteen lucerne cultivars were sown at Deniliquin, New South Wales, in 1976. The aim of the trial was to assess these cultivars for their performance on an irrigated heavy clay soil infected by P. megasperma. The unforeseen arrival of the spotted alfalfa aphid (SAA) in December 1977 complicated the original assessment, but provided an opportunity of assessing the combined effects of SAA and P. megasperma. Twelve of the cultivars were introduced from the USA, and six were Australian lines. The American cultivars were AS1 3, AS1 3R, AS49, AS49R, WL451, WL501 R, WL508, WL512, DeKalb 167, DeKalb 185, Resistador II and Lahontan. None of these was damaged by SAA, and all except WL508 appeared to be well adapted to the heavy clay soil. The Australian cultivars Hunter River, Paravivo and Siro Peruvian were all badly affected by the aphid, and in Siro Peruvian the loss in production was accentuated by Phytophthora root rot. The Australian cultivar Falkiner and its parent line, Lahontan Cycle 4, carried large populations of aphids, but the effect on their production was only slight and temporary. Another Australian line, C3 Composite, yielded well until the aphid infestation, when its yield was temporarily reduced, but recovered after the aphids disappeared. Neither Falkiner nor C3 Composite was affected by root rot.
Regional evaluation of wheat genotypes for grain protein level in the central west of New South Wales
Authors: Seif E , Balaam LN
Published: March 2005

The analysis of wheat protein data from ten homozygous genotypes grown at six locations in 4 years gave a heritability estimate of 50%, and another of 65% from a sub-set of genotypes of similar maturity. The first-order interactions, genotype x year and genotype x location, were small and nonsignificant. An examination of the variance of a genotype mean indicated that selection in regional testing programs could be based on data from as few as three trials. Laboratory error represented a large proportion of this variance, thus more than one laboratory determination will be necessary.
Losses in sunflower yield caused by Alternaria helianthi in southern Queensland
Authors: Allen SJ , Kochman JK , Brown JF
Published: March 2005

The effect of A. helianthi on yield of sunflower (cv. Hysun 30) was assessed in two field trials at Hermitage and Gatton in southern Queensland during the 1977-78 season. Plots were (i) inoculated with spore suspensions of A. helianthi to encourage an epidemic or, (ii) sprayed regularly with the fungicide captafol to prevent disease development. Conditions were dry at both trial sites except for one week of wet overcast weather when an epidemic of A. helianthi developed. At this time, plants in the Hermitage trial were commencing anthesis, while those in the Gatton trial were approaching maturity (4 weeks post anthesis). After the wet period the epidemic declined in the Hermitage trial, and a low level of disease was present at maturity. At Gatton the disease caused premature leaf senescence in unsprayed plots, while foliage in sprayed plots remained green. Control of the epidemic that began at anthesis increased oil yield by 28%, mainly through increased seed number. There was also a small increase in 1000 seed weight but no significant increase in oil content. Control of the epidemic that began just before maturity increased oil yield by 20%, mainly because of increased 1000 seed weight and a small increase in oil content. It appears that the plant growth stage at the time the disease epidemic occurred determined which yield attributes were most affected.
Soil nitrogen status and pasture productivity after clearing of brigalow (Acacia harpophylla)
Authors: Graham TWG , Webb AA , Waring SA
Published: March 2005

At 31 sites of solodized solonetz and solodic soil in central Queensland, the total soil nitrogen (N) and organic carbon (OC) levels of pasture and crop areas were compared with matched uncleared areas of A. harpophylla-Dawson gum (Eucalyptus cambageana)
Hay supplements to overcome underfeeding of dairy cows. 2. Late lactation
Authors: King KR , Stockdale CR
Published: March 2005

The effect of hay supplementation on the performance of dairy cows on a restricted intake of paspalum-dominant perennial pasture was studied in two 21 -day periods in the eighth and ninth months of lactation. In each period, there were three groups fed pasture only at mean intakes of 15.2, 11.5 and 7.3 kg/cow day-1, two groups fed at similar pasture restriction levels and supplemented with hay ad libitum, and one further group fed an average of 7.3 kg of pasture supplemented with only 4.3 kg of hay. The data were analyzed by regression, using total dry matter intake as the dependent variable, and pseudovariables were used to examine the effects of hay feeding. The relations between total dry matter intake and milk, butterfat, protein and solids-not-fat production, and change in body condition of dairy cows were not altered by ration composition. Milk production declined linearly by 0.66 kg and 0.31 kg/cow day-1 in the eight and ninth months of lactation, respectively, for each kg reduction in total dry matter intake. Similar responses were obtained for butterfat, protein and solids-not-fat production. Gain in body condition of the cows also decreased as total intake fell, but the relation was curvilinear and not affected by stage of lactation. It was concluded that high quality hay can be used to overcome shortages of paspalum-dominant perennial pasture in autumn, and that it has similar. nutritive value to pasture in terms of milk production and body condition.
The comparative productivity of five ewe breeds. 4. Growth and carcase characteristics of purebred and crossbred lambs
Authors: Atkins KD , Gilmour AR
Published: March 2005

The growth to slaughter and carcase characteristics of purebred and crossbred lambs from five ewe breeds were compared in an experiment in 1971 and 1972 at Temora Agricultural Research Station. The ewe breeds were a Border Leicester x Merino fixed halfbred (BLM), Corriedale, Polwarth, a South Australian strong wool (SA Merino) and a medium wool Peppin strain of Merino. In each year, ewes of each breed were joined either to their own breed of ram or to Dorset Horn rams. The analysis used tested whether differences between ewe breeds in crossbred performance were halved compared with the differences between ewe breeds in purebred performances. The results supported this hypothesis for all characters measured. The largest breed effects on lamb performance were found for growth rate. Compared with the overall mean, the growth rates to weaning for purebred lambs were 118%,102%, 90%, 99% and 91% 10 for the BLM, Corriedale, Polwarth, SA Merino and Peppin Merino, respectively. The deviations from 100% for crossbred lambs were halved. Differences between breeds for carcase traits were estimated at the same carcase weight. South Australian Merino lambs had a lower dressing percentage than lambs from .the other breeds. Polwarths had the greatest depth of fat at the 12- 13th rib. Skins from Merino lambs had shorter staples and higher visual counts than skins from the other breeds. However, it was concluded that breed differences in carcase and skin characters, independent of carcase weight, were of little value in an economic comparison of the breeds for total productivity.
Gastro-intestinal parasites in sheep in an arid environment
Authors: Gray SJ , Kennedy JP
Published: March 2005

Internal parasitism and its effects on survival, wool growth and liveweight gain of weaner sheep were studied over 3 years from 1977 to 1979 at Fowlers Gap Research Station, Broken Hill, New South Wales. During this period, annual rainfall was 33, 152 and 141 % respectively, of the annual mean of 195 mm. Worm burdens and production of sheep given anthelmintic treatment at approximately monthly intervals were compared with those in untreated sheep. Total worm counts in untreated sheep were low, ranging from 1 5 to 3750. Nematodirus spp. were the most common nematode parasites recovered. lnfections with Trichostrongylus spp, were recorded in 2 of the 3 years; T. rugatus was the only species represented when species identification was made in 1979. Infections of Haemonchus contortus were only detected in the last year. Tapeworms (Moniezia spp.) were occasionally recovered. Anthelmintic treatment reduced worm burdens to a very low level but had no significant effect on survival rate, liveweight gain, or wool production. We concluded that in the arid areas of western New South Wales, worm infection would not limit production or cause mortality in young sheep, except in unusually wet years.
Nutritive value of alkali-treated wheaten straw fed to sheep with supplements of either lupins or barley and urea
Authors: Valentine SC , Wickes RB
Published: March 2005

Untreated straw and alkali-treated straw were prepared by spraying long wheaten straw in windrows with water or a 6.6% (w/v) solution of sodium hydroxide to give a concentration of sodium hydroxide of 7g per 100 g straw. Merino wethers were fed the straws ad libitum with or without a supplement of either lupins or a mixture of barley and urea. The in vivo organic matter digestibilities (%) of the alkali-treated straw diets supplemented with lupins (61.3) or barley and urea (59.3) were greater (P<0.05) than those of the untreated straw diets supplemented with lupins (54.6) or barley and urea (55.7). The intakes of dry matter (g day-1) and digestible energy (MJ day-1), respectively, were greater (P<0.01) for the sheep offered alkali-treated straw supplemented with lupins (769, 7.7) or barley and urea (847,7.9) than for those offered untreated straw supplemented with lupins (598, 5.4) or barley and urea (639, 5.9). Sheep offered the supplemented alkali-treated straw diets produced 39% more wool and lost less (P<0.05) liveweight than sheep offered the supplemented untreated straw diets. Retention of nitrogen (g day-1) by sheep was greater (P<0.01) when the alkali-treated and untreated straws, respectively, were supplemented with barley and urea (3.6, 2.8) than with lupins (1-9, 0.9). It is concluded that a more effective method of application of sodium hydroxide must be developed if treatment of straw with sodium hydroxide is to become a routine and economic technique for use on southern Australian farms.