bluuebunny/crossref_metadata_2025 huggingface dataset:
Susceptibility of subterranean clover varieties to rust under controlled environment and field conditions
Authors: Barbetti MJ , Nichols PGH
Published: March 2005

Thirty-two subterranean clover varieties, comprising 17 commercial cultivars, 1 named variety and 14 promising midseason breeding and introduced lines, were screened for resistance to rust (caused by Uromyces trifolii-repentis) under controlled environment conditions, and where possible, comparisons were made with their performance in field plots. There were large differences between varieties in the incidence and severity of rust on plants. Under controlled environment conditions, cvv. Gingin, Meteora and Enfield, and to a lesser extent Larisa and Trikkala, had the lowest levels of rust leaf infection, the lowest rust pustule densities and the smallest rust pustules. Seaton Park had a relatively low pustule density and CPI 89830F had relatively small pustules. Gingin and Enfield had the least leaf collapse. Green Range was the most susceptible under controlled environment conditions, followed by Bacchus Marsh, Karridale, CPI 47308C and CPI 89841E. Under field conditions, Enfield, Meteora, Trikkala and CPI 89822H were rust free, while Larisa, CPI 47308C, CPI 65328F, 75S13-12, 76841-1, CPI 89830F and CPI 89880J had good resistance. Green Range was clearly the most susceptible under field conditions, followed by Seaton Park, Karridale, Bacchus Marsh, CPI 89774F and CPI 89841E. While there was often good correlation between the field and controlled environment data for the different parameters, the resistance rankings of some varieties varied widely, depending upon whether screened under controlled environment or field conditions. Green Range, Karridale, Seaton Park and CPI 89841E were highly susceptible to rust under both controlled and field conditions, indicating that either environment could be successfully used to identify highly susceptible varieties. The high degree of resistance observed in Enfield, Gingin and Meteora, and to a lesser extent in Larisa and Trikkala, suggests their value as parents in breeding programs for rust resistance.
Susceptibility of subterranean clover varieties to powdery mildew under controlled environment and field conditions
Authors: Barbetti MJ , Nichols PGH
Published: March 2005

Thirty-three subterranean clover varieties, comprising 16 commercial cultivars and 17 promising midseason breeding and introduced lines, were screened for resistance to powdery mildew (caused by Erysiphe polygonii) under controlled environment conditions, and where possible, comparisons were made with their performance in field plots. There were large differences between varieties in the incidence and severity of powdery mildew on plants. Under controlled environment conditions, Tallarook, CPI 47308C, CPI 89860D, 75S13-12, CPI 6.53284 CPI 89820D and Clare had the lowest levels of leaf infection, the lowest mildew sporulation scores and the least amount of leaf scorching from mildew infection. Karridale had the highest level of leaf infection, followed by 69837-1, 76841-1, Junee, Bacchus Marsh and 69S37-3. Under field conditions, Tallarook, CPI 47308C, CPI 65328A and CPI 65328F were mildew-free, while CPI 89777C, CPI 89860D, CPI 89830F, CPI 89841E, Clare and Rosedale had good resistance. Junee was clearly the most susceptible under field conditions, followed by 76S41-1, 69837-3, Karridale, Bacchus Marsh and 69S37-1. There was generally excellent correlation between the different powdery mildew disease parameters, namely leaf infection, mildew sporulation and leaf scorch, measured under controlled environment conditions, and there was also good overall correlation between controlled environment and field data. Bacchus Marsh, Junee, 69337-1, 69837-3 and 76341-1 were highly susceptible under both controlled environment and field conditions, indicating that either environment could be used to identify highly susceptible varieties. Under controlled environment conditions, a high degree of resistance was observed in Clare, CPI 47308C, CPI 65328A, CPI 89820D, CPI 89860D and 75S13-12, while field plots of the varieties Tallarook, CPI 47308C and CPI 65328A showed a complete absence of powdery mildew. These varieties may have value as parents in breeding programs for powdery mildew resistance.
Reclamation of a failed subsurface drainage system on an unstable clay soil
Authors: Gardner WK , Fulton MC , Flood RG
Published: March 2005

The soil structure of a dispersive clay soil on which a subsurface drainage system had failed was modified by applying gypsum (5 t/ha) and growing a crop of sunflowers. The sunflower crop and gypsum application increased macroporosity from 8 to 15% and stabilised the clay microstructure. Sunflowers without gypsum produced a similar increase in soil macroporosity but with a potentially more dispersive clay microstructure. Gypsum alone produced a stable clay microstructure and intermediate values (about 11%) of macroporosity. The yield of wheat was similar on both drained and undrained areas (4 t/ha) following the sunflower crop with and without gypsum application, whereas on untreated areas, yields were 2.1 t/ha in the absence of drainage and 3.3 t/ha when drained.
Improved methods for zinc and boron application to mango (Mangifera indica L.) cv. Kensington Pride in the Mareeba-Dimbulah district of North Queensland
Authors: Littlemore J , Winston EC , Howitt CJ , O'Farrell P , Wiffen DC
Published: March 2005

Following soil and foliar treatments with zinc and boron, concentrations of leaf microelements were measured in mango trees (Mangifera indica L. cv. Kensington Pride) in order to determine the best method of application. Quarterly foliar application of zinc sulphate (1.0%) was the most cost-effective way to maintain leaf zinc above the critical concentration of 20 mg/kg dry matter. Yearly soil application of 50 g of Solubor per tree maintained leaf boron above the adequate concentration of 50 mg/kg. Single Solubor soil applications of 100 and 200 g/tree.year were phytotoxic to mango trees, with severe leaf burn associated with leaf boron concentrations of 320 mg/kg. In general, mango yield was not significantly (P>0.05) affected by any of the treatments, nor was it significantly (P>0.05) correlated with zinc or boron leaf concentrations.
Yield comparison of Australian selections of almond cv. Nonpareil
Authors: Taylor BK , Blennerhassett RM , Hill SJ , Welsh M
Published: March 2005

Eight Nonpareil almond clones on Nemaguard rootstock were yield-tested in a field trial at Irymple, Victoria, for 4 cropping seasons (1986-89). Although few significant differences in yield were recorded in any year, the results showed that the Nonpareil clones differed in total yield and in total yield per unit of butt cross-sectional area by as much as 50%. For example, clone L54/3 produced a total dry kernel yield per tree per unit of butt crosssectional area of 51.2 kglcm2, while the high yielding clone G11/16 produced a yield of 77.6 kg/cm2. The 3 top-yielding clones (GI 1/16, P7/29 and K5/7) produced total dry kernel yields (1986-89) per tree per unit of butt cross-sectional area of 77.6, 73.6 and 71.7 g/cm2. However, clone K5/7 proved to be subject to non-infectious bud failure, and it is concluded that clones G11/16 and P7/29 could be useful, high-yielding clones for the Australian almond industry.
Ethephon concentration and timing effects on thinning Winter Cole pears
Authors: Bound SA , Jones KM , Koen TB
Published: March 2005

Ethephon was tested as a thinner for mature Winter Cole pear trees in a trial conducted at Nubeena in south-eastem Tasmania during the 1988-89 season. Trees were treated with ethephon (0, 50, 100, 200 or 400 mg/L) at full bloom or 11 days after full bloom, or at both times. Models were fitted to the response variables of numbers of fruit per cm2 limb cross-sectional area and per 100 blossom clusters. The full bloom sprays removed significantly (P<0.05) more fruit than the later sprays. Spraying at both times gave an unexpected intermediate result between the full bloom and the later sprays. Although most treatments produced more thinning than the control, only the higher concentrations of ethephon applied at full bloom or at both times were close to achieving the required thinning results. It was concluded that although ethephon applied at full bloom is a feasible thinner for pears, further work is needed before accurate recommendations on concentration or time of application can be made.
The relationships between liveweight, growth from weaning to mating and conception rate of Bos indicus cross heifers in the dry tropics of north Queensland
Authors: Doogan VJ , Fordyce G , Shepherd RK , James TA , Holroyd RG
Published: March 2005

Factors influencing the conception rates of 1332 Bos indicus cross maiden heifers in the dry tropics of North Queensland were studied between 1973 and 1986. The heifers, which were 112 and 314 Bos indicus (Brahman or Sahiwal) crosses with Bos taurus, were mated at 24-27 months of age over a 3-month period commencing in mid to late January. The effects of liveweights and growth rates on conception rate were initially assessed in separate models which always included cohort (year of branding group) as an additional factor. Cohort and liveweight at weaning, 18 months of age or the start of mating significantly (P<0.05) affected conception rate in maiden heifers. Response to liveweight was curvilinear, being marked for liveweights up to 125-150 kg at weaning, 200-225 kg at 18 months of age and 225-250 kg at the start of mating, with reduced response for greater liveweights. Liveweights of about 270 kg were indicated as targets at the start of mating in a typical year to achieve an 80% conception rate. Average daily gains during the post-weaning dry season and the dry season prior to mating did not influence conception rates after adjusting for cohort. Further analyses using models incorporating both liveweight and growth rate with and without the cohort effect gave indications that the significant cohort effect on conception rate was partly related to post-weaning dry season growth rate. F2 et seq. maiden heifers with low liveweights at either 18 months of age or mating had appreciably higher conception rates if they had gained weight in the post-weaning dry season, rather than losing weight.
Chronological age and dentition effects on carcass and meat quality of cattle in northern Australia
Authors: Wythes JR , Shorthose WR
Published: March 2005

The effects of chronological age and dentition on the liveweight, carcass weight, bruising and muscle properties of 348 cows and 370 steers were examined in 5 experiments in Queensland (1982-83). Birth dates were known only for the cows in experiments 1 and 2, and for the steers in experiment 5; with ages categorised as 4 years and less (young), 5-10 years (mature) and greater than 10 years (old). The number of permanent 'incisor' teeth were recorded for all animals. The cattle were weighed (unfasted), transported to an abattoir and given access to water and hay (except in experiment 5). Mustering to slaughter periods varied from 2 to 7 days. Half the carcasses were electrically stimulated in experiments 1 and 2. In general, old and mature cows with 8 teeth had heavier (P<0.05) mean liveweights than did young cows with 4 teeth, and both had heavier (P<0.05) liveweights and carcass weights than those with 2 teeth. Old cows with 8 teeth also had the lowest (P<0.05) mean dressing percentage, while mature cows had the greatest (P<0.05) fat depth. There was no consistent trend between groups in bruise score. Steers with 8 teeth had a greater (P<0.05) mean liveweight, carcass weight, dressing percentage and rib fat depth than other dentition groups, and a greater (P<0.05) bruise score in experiment 5 only. There was no significant effect of chronological age or dentition on the shear force values or cooking losses of M. longissimus dorsi (LD) for cows. In 1 experiment, steers with 8 teeth had a greater (P<0.05) peak force-initial yield value and lower (P<0.05) cooking loss than other dentition groups. Mature cow carcasses cooled more (P<0.05) slowly than those of other ages. Over all experiments, there were more (P<0.05) high pHz4 carcasses among the combined 6 and 8 teeth group than the combined 2 and 4 teeth group (10.2 v. 2.3%).
A comparison of various methods of feeding supplements of urea, sulfur and molasses to weaner heifers during the dry season in northern Queensland
Authors: McLennan SR , Hirst DJ , Shepherd RK , McGuigan KR
Published: March 2005

Over 3 dry seasons (1984-86), delivery systems of urea supplements were evaluated on weaner heifers grazing native pasture. Daily treatments per heifer were urea-ammonium sulfate (US) (28g + 6g), via the drinking water; urea-molasses (UM) (30g + 250g), via roller drum lick feeders; UM2 (60g + 1000g), via open troughs. Rainfall recordings were well above average in all dry seasons. The only liveweight response to supplementation occurred in 1986, during a dry period from June to October. During this period the liveweight performance of the US group was improved relative to the control group (+7 v. -57 g/heifer.day; P<0.05). The response of the UM2 group (+82 g/heifer.day) exceeded (P<0.05) that of all other groups. There was no response to the UM supplement (-51 g/heifer.day). Over the combined dry and following wet seasons the UM2 group grew faster (P<0.05) than all other groups. Ammonia-nitrogen concentrations in the rumen fluid of heifers, measured in the 1984 and 1986 dry seasons, were very low for the control group (7-54 mg/L rumen fluid) but were much higher in the US group 2 h after drinking (108-152 mg/L). At 18 h after drinking, the ammonia-nitrogen concentration had declined markedly in the US group (30-54 mg/L) but, in 2 of 3 observations, was still higher than that of the controls (significantly in 1 case; P<0.05).
Responses in milk yield from feeding grain and meat-and-bone meal to cows grazing tropical pastures
Authors: Davison TM , Williams D , Orr WN , Lisle AT
Published: March 2005

An experiment was conducted with 36 Holstein-Friesian cows to determine the effect on milk yield and milk composition of feeding maize grain with or without meat-and-bone meal (MBM) at high levels of pasture on offer. Cows were offered ground maize with and without MBM to give supplements of 3.0, 5.5 and 8.0 kg DM/day at 16% or 10% crude protein. Animals grazed nitrogen-fertilised tropical grass and grass-legume pastures. Milk production was recorded over a 300-day lactation. Milk yields over 300 days at 3.0, 5.5 and 8.0 kg DM/day averaged 5435, 5605 and 5882 kg/cow, respectively. For milk yields over both 100 and 300 days, a linear response to grain supplement occurred. This represented 0.22 kg milk/kg DM (P<0.05) for the first 100 days, and 0.30 kg milk/kg DM (P=0.087) over the 300-day lactation. Cows receiving MBM tended to lose less (P=0.068) liveweight in the period 1-100 days and to gain more (P=0.054) between 100 and 300 days than cows without MBM. Milk yields across treatments for cows fed with and without MBM averaged 2143 and 2061 kg/cow (P>0.05) for days 1-100, and 5668 and 5614 kg/cow (P>0.05) for days 1-300 of lactation.
Short-term response in solids-not-fat to grain fed in addition to molasses for dairy cows grazing tropical pastures
Authors: McLachlan BP , Orr WN , Silver BA
Published: March 2005

Holstein-Friesian cows in mid to late lactation grazed tropical grass-legume pastures with no supplement (C); 2.7 kg DM molasses/cow.day (M); or 2.6 kg DM molasses + 2.5 kg DM grain/cow.day (MG). Daily milk yields over the 8 week experimental period were 10.4, 11.2 and 12.9 kg/cow for C, M and MG. The MG supplementation increased solids-not-fat (SNF), protein and lactose percentages in milk, with average SNF values of 8.02, 8.10 and 8.24% (P<0.05), and lactose values 4.46,4.50 and 4.58% (P<0.057), for weeks 5-8; and average protein values for weeks 1-8 of 2.96, 3.02 and 3.10% (P<0.05) for C, M and MG, respectively. Molasses alone did not substantially increase the protein and lactose content of milk, but additional energy in the form of maize increased these values. If SNF percentages in milk were low, maize plus molasses feeding did not improve the quality to the legal minimum of 8.5% in 8 weeks.
Comparison of two management systems of dairy farmlets based on conservation of either hay or silage
Authors: Thomas GW , Mathews GL
Published: March 2005

Two management systems for dairy farms, early (silage farmlet) and late (hay farmlet) conservation, were compared for milk production in 4 consecutive years, at 2 cowsha. Half of the total silage farmlet area was made to wilted silage in each year. The remaining area was conserved as direct-cut silage in the first year and hay in the fourth year. About 40-50% of the hay farmlet area was made to hay. Over the 4 years, the silage farmlet produced an average of 8.2% more milk and 11.9% more (P<0.01) milk fat per year than the hay farmlet. The improvement in milk and milk fat production averaged 2.7 and 5% (P<0.01) in the spring and 27.4 and 30% (P<0.01) in the period from commencement of supplementary feeding in the summer. On average, the silage farmlet conserved a greater area, but because of high storage losses and greater consumption, it required more brought-in feed than the hay farmlet.
Monitoring the performance of a broad-based calibration for measuring the nutritive value of two independent populations of pasture using near infrared reflectance (NIR) spectroscopy
Authors: Smith KF , Flinn PC
Published: March 2005

Near infrared reflectance (NIR) spectroscopy is a rapid and cost-effective method for the measurement of organic constituents of agricultural products. NIR is widely used to measure feed quality around the world and is gaining acceptance in Australia. This study describes the development of an NIR calibration to measure crude protein (CP), predicted in vivo dry matter digestibility (IVDMD) and neutral detergent fibre (NDF) in temperate pasture species grown in south-western Victoria. A subset of 116 samples was selected on the basis of spectral characteristics from 461 pasture samples grown in 1987-89. Several grass and legume species were present in the population. Stepwise multiple linear regression analysis was used on the 116 samples to develop calibration equations with standard errors of 0.8,2.3 and 2.2% for CP, NDF and IVDMD, respectively. When these equations were tested on 2 independent pasture populations, a significant bias existed between NIR and reference values for 2 constituents in each population, indicating that the calibration samples did not adequately represent the new populations for these constituents. The results also showed that the H statistic alone was inadequate as an indicator of equation performance. It was confirmed that it was possible to develop a broad-based calibration to measure accurately the nutritive value of closed populations of temperate pasture species. For the resulting equations to be used for analysis of other populations, however, they must be monitored by comparing reference and NIR analyses on a small number of samples to check for the presence of bias or a significant increase in unexplained error.
Control of silverleaf nightshade (Solanum elaeagnifolium) increases the grain yields of wheat
Authors: Lemerle D , Leys AR
Published: March 2005

The effect of controlling silverleaf nightshade with 2,4-D or glyphosate for 4 consecutive years on the yield of wheat was determined in a field experiment in southern New South Wales. Silverleaf nightshade was either controlled throughout summer with 2,4-D or glyphosate, or treated once with 2,4-D each February from 1979 to 1982. After 4 years, the initial density of silverleaf nightshade increased from 8 to 17 shootsJm2 in both the untreated controls and the plots treated with 2,4-D in February. Treatment throughout each summer with 2,4-D retarded this increase to 11.4 shootslm2, and treatment with glyphosate reduced the population to 1.6 shoots/m2. The grain yield of wheat was not affected by prior control of silverleaf nightshade in 1979 or 1980, but in 1981-82 there was a significant (P<0.05) yield increase from some herbicide treatments, compared with the unsprayed controls. In 1981, repeated application of glyphosate or 2,4-D increased yield by 14 and 9%, while the application of 2,4-D in February increased yield by 5%. In 1982, a drought year, the responses were much greater, with corresponding yield increases of 69, 49 and 17% from these treatments.
Reducing height and lodging in rapeseed with growth regulators
Authors: Armstrong EL , Nicol HI
Published: March 2005

The plant growth regulators (PGRs) ethrel (20% a.i. 2-chloroethane phosphonic acid), PP 333 (25% w/v a.i. paclobutrazol), cycocel (50% w/v a.i. chlormequat chloride), pix (5% w/v a.i. mepiquat chloride) and EL 500 (50% w/w a.i. flurprimidol) were applied to bulky crops of Jumbuck, Marnoo and RU 14 rapeseed at Cowra and Woodstock in central-western New South Wales, in an effort to reduce their height and lodging. The most effective growth retardants under evaluation were PP 333 and EL 500, and this was achieved without apparent phytotoxicity. Height reductions were enhanced as rates were increased from 0 to 2 Lha, and the heights of Jumbuck, Mamoo and RU 14 were reduced on average by 22% (from 159 to 124 cm), 26% (from 136 to 100 cm) and 14% (from 150 to 129 cm), respectively. Significant reductions in lodging accompanied these changes. Ethrel resulted in some phytotoxicity, while pix and cycocel had little or no measured effect on any plant characters. Jumbuck was the tallest variety and the most severely lodged, and under these conditions, yield responses to PGR were large (900 kg/ha or 54%). Shorter, erect plants produced an even, compact pod canopy, and as a result, ripening was more uniform, pod shattering reduced and harvesting more efficient. In situations where seed yields were increased, these practical considerations, rather than physiological responses (e.g. pod and seed set), were largely responsible. These findings support further research and commercial development of PGRs for use in canola production in the more favoured areas and support the inclusion of reduced plant height and increased stem strength as integral components of the overall breeding objectives for canola in Australia.
Grain field of Fiord faba bean in relation to strain of Rhizobium
Authors: Silsbury JH
Published: March 2005

Drill-sown field experiments were established in 1988 at each of 6 sites in the cereal districts of South Australia to assess the responses of Fiord faba bean to inoculation with 2 different strains of Rhizobium. Each trial was sown and managed in co-operation with a farmer using standard farm equipment. The 4 inoculation treatments imposed were: no inoculation; Group E, strain SU 391; strain SU 303; SU 391 + SU 303. Samples were taken during early vegetative growth for determination of nodulation, nodule activity and plant dry weight. Inoculation significantly (P<0.05) improved nodulation, with SU 303 being better than SU 391, but early plant growth did not respond to inoculation. Grain yield at the end of the season was improved an average of 20% by inoculation; 15% for SU 391 and 28 % for SU 303. It is concluded that SU 303 is a better inoculant for Fiord faba bean than the present Group E inoculant, strain SU 391.
Effect of time of pruning and hydrogen cyanamide on growth and development of glasshouse-grown Cardinal grapes
Authors: Cirami RM , Furkaliev DG
Published: March 2005

Weekly pruning treatments combined with hydrogen cyanamide applications from early May to late June in 1987 and 1988 were evaluated for their ability to advance budburst, flowering, colouring and maturity of Cardinal grapes grown in unvented, unheated vegetable glasshouses. The glasshouse provides protection from frost, hail, wind and birds, and permits production of unblemished fruit. Hydrogen cyanamide-treated vines reached maturity approximately 1 month earlier (P<0.05) than untreated vines pruned on the same day. Budburst occurred 28-61 days after pruning with application of hydrogen cyanamide. The interval between pruning and vine responses was variable over the 2 years, but manipulation of the time of pruning significantly (P<0.05) affected the time of ripening in the glasshouse environment. Ripe grapes were produced from 7 November to 19 December by using different pruning times.
Lifetime productivity of crossbred cows. 2. Age and weight at first oestrus, calf birth weight, assisted calvings, calving interval and reproduction rate
Authors: Newman S , Deland MP
Published: March 2005

Crossbred heifers were born in 1974 from 7 breeds of cattle by mating Hereford bulls to Shorthorn cows, Hereford bulls to Friesian cows (calves double-suckled), Hereford bulls to Jersey cows (and Jersey bulls to Hereford cows), and using semen or natural service of Sahiwal, Charolais, Simmental and Brahman bulls on Hereford cows. Breed differences were important sources of variability for age and weight at first oestrus. The heifers were joined with Hereford bulls to produce backcross progeny during the years 1976-84 in a semi-arid environment. Parity (confounded with year and age of dam) and its interaction with breed had significant effects on frequency of assisted calvings, birth weight, calving rate and weaning rate. On average, over all parities, European cross dams (Charolais, Simmental) had calves of higher birth weight than other types but also had more assisted calvings, a lower calving rate and longer calving interval. Dairy cross dams (Friesian, Jersey) had early puberty, short calving intervals, few assisted calvings and higher calving rates. Zebu cross cows (Brahman, Sahiwal) had poor early reproductive performance due to late onset of oestrus, but similar or better subsequent calving rates and calving intervals. Their calves had lower birth weights but required similar assistance to Europeans. Shorthorn cross cows had similar calving intervals and more assisted calvings than other types in spite of their calves having average birth weights.
Rapid evaluation of rumen protection status of orally administered DL-methionine mixes using an HPLC analysis of plasma methionine
Authors: Stephenson RGA , PalmerC L , Suter GR
Published: March 2005

The measurement of plasma methionine concentrations with high pressure liquid chromatography (HPLC) with a protein hydrolysate column was examined as a means of evaluating the rumen protection status of DL-methionine mixes after oral administration. Plasma methionine concentrations were measured 2, 4, 6 and 8 h after 5 different mixes had been administered to the rumen of 3 sheep by stomach tube. The plasma values were compared with the pretreatment profile (1.2-16.7 �mol/L) obtained in the test sheep, and those obtained after abomasal and subcutaneous administration. The results suggest that none of the mixes were significantly protected from bacterial degradation in the rumen. The positive control treatments of subcutaneous or abomasal administration resulted in >10-fold increases in plasma concentrations of methionine (e.g. from 28 to 414 �mol/L). A method of administration that required the sheep to raise their heads about 30 cm to lick a molasses + methionine mix increased subsequent plasma methionine concentrations 5 times (from 44 to 267 �mol/L). Oral administration of 2 mixes using a drench gun also resulted in increased plasma methionine in some sheep, suggesting that these procedures allowed some methionine to bypass the rumen mechanically. A follow-on wool growth experiment using methionine + molasses mixes administered either from a 'licker' 30 cm above head level or in the feedbin failed to increase either wool growth or plasma methionine. The HPLC procedure for methionine analysis proved successful for the qualitative laboratory evaluation of the rumen protection status of methionine mixes. It is concluded that this 24 h methionine test and analysis procedure can partly replace the costly and lengthy in vivo procedure of measuring responses in wool production.
Effects of water stress on curly Mitchell grass, the common armyworm and the Australian plague locust
Authors: Phelps DG , Gregg PC
Published: March 2005

Temporal water and nitrogen relations of curly Mitchell grass, Astrebla lappacea (Lindl.) Domin, in response to single waterings of 0, 20, 60 and 180 mm were studied. Effects on the survival and development of the common armyworm, Mythimna convecta (Walker), and the Australian plague locust, Chortoicetes terminifera (Walker), were recorded. Glasshouse trials were conducted to ascertain the level of rainfall required for insect survival. More than 20 mm of rainfall was needed for insect survival. Even at 60 mm, development was retarded in some instances. Plant nitrogen was positively correlated (R2 = 0.51) with plant moisture. Insect survival was better correlated with plant moisture (R2 = 0.61) than with plant nitrogen (R2 = 0.41).
Response of subterranean clover varieties to Cercospora disease under a controlled environment and in the field
Authors: Barbetti MJ
Published: March 2005

Seventeen commercial cultivars of subterranean clover and 10 introduced lines were screened for resistance to cercospora disease (caused by Cercospora zebrina) under a controlled environment, and responses were compared with their performance in the field. There were large differences between varieties in the severity of cercospora disease under both conditions. There was, overall, good correlation between data from the field and those from the controlled environment for the different parameters. Daliak, Dalkeith, Esperance, Mt Barker, Nungarin and Rosedale were highly susceptible to cercospora disease under both controlled environment and field conditions, while Clare, Larisa, Meteora and Yarloop were assessed as having a high degree of resistance under both conditions. A few individual resistance rankings varied widely between the 2 conditions. The results indicate that controlled conditions can be used to identify resistant lines.
Nutritional characteristics of selected species of Acacia growing in naturally saline areas of Western Australia
Authors: Craig GF , Bell DT , Atkins CA
Published: March 2005

The forage potential of 11 species of Acacia from naturally saline areas of Western Australia was assessed by analysing their nutritive characteristics and acceptability to sheep. The crude protein content of new shoots was greater than that of mature phyllodes [8-25 v. 6-12% dry matter (DM) respectively]. This was reflected in higher in vitro DM digestibility (IVDMD) values (34-59% in shoots v. 22-54% in phyllodes). IVDMD appeared to be reduced by high concentrations of neutral and acid detergent fibre (NDF and ADF) and acid detergent lignin (ADL). The least acceptable species generally had high values of NDF. The most promising species for use as perennial fodder shrubs were Acacia ampliceps, A. brunzalis, A. cyclops and A. ligustrina. Mature phyllodes of these species had IVDMD >40%, ADL <20% and crude protein level of all foliage in the range 8-17% DM. A. patagiata and A. ixiophylla were acceptable to sheep; however, crude protein levels and IVDMD of phyllodes were relatively low. Although new shoot material of A. eremaea, A. inceae, A. aff. lineolata, A. mutabilis and A. redolens had relatively high levels of crude protein, mature phyllodes of these species had low levels of protein, IVDMD <40% and high NDF concentrations (>50% DM), which suggests that these species would be unsuitable as animal feed. The ability of salt-tolerant acacias to grow in marginal land means they may provide supplementary forage in times of drought.
Sensitivity of eight cereal and legume species to the compaction status of deep, sandy soils
Authors: Henderson CWL
Published: March 2005

The effects of soil compaction and deep ripping on the growth and yield of crop (wheat, barley, oats, triticale, narrow leaf lupins and field peas) and pasture species (barrel medic and subterranean clover) were investigated for deep, sandy soils near Geraldton, Western Australia. In 1984 (an average rainfall season), growth and yields of all species were substantially reduced by soil compaction. Lupins were not included in the experiment. Barley, wheat and pea yields were reduced by around 45%; oat and triticale yields by 30%; and spring biomass of both pasture species was reduced by about 30%. The differences in response between the species were not significant (P>0.05). In 1985 (a very dry year), amelioration of soil compaction by deep ripping increased the dry matter at flowering of all the species, including lupins, by about 30%. Severe water stress in the cereals after flowering prevented the conversion of this dry matter advantage into grain yield differences. Because of late flowering and slow maturation, the yield of the oats was significantly (P<0.05) lower on the deep-ripped areas, compared with the yield on the compacted soil. Deep ripping increased the yield of peas by 60% and lupins by 20%, probably because flowering and seed filling were completed before the onset of severe water stress. For deep, sandy soils in mediterranean environments, maximum economic benefit would normally accrue from deep ripping prior to the cereal phase, given that current agronomic principles generally preclude the growing of peas on these soils. Selection of cereal species mainly depends on relative yields and prices; however, the results suggest that use of cultivars with rapid early growth, early flowering and quick maturity would maximise the response to compaction amelioration and minimise the risk of poor grain filling.
Lupin grain yields and fertiliser effectiveness are increased by banding superphosphate below the seed
Authors: Jarvis RJ , Bolland MDA
Published: March 2005

Five field experiments with lupins (Lupinus angustifolius) measured the effectiveness, for production, of 4 superphosphate placements either: (i) drilled with the seed to a depth of 4 or 5 cm; (ii) applied to the soil surface (topdressed) before sowing; or (iii) banded 2.5-5 cm and 7.5-8 cm below the seed while sowing. Levels of applied phosphate (P) from 0 to 36 kg P/ha were tested. In all experiments lupin grain yield responded to the highest level of superphosphate applied. At this P level, the average grain yield from all trials was 1.16 t/ha for the deepest banded treatment. This was 0.38 t/ha (49%) better than P drilled with the seed, and 0.62 t/ha (115%) better than P topdressed. Relative to superphosphate drilled with the seed and regardless of the lupin cultivar or the phosphate status of the soil, the effectiveness of superphosphate was increased by 10-90% by banding below the seed, and decreased by 30-60% by topdressing. Increasing the levels of superphosphate drilled with the seed generally reduced the density of seedlings and reduced early vegetative growth, probably due to salt or P toxicity. However, during the growing season, the plants treated with high levels of superphosphate recovered, so that eventually yields of dried tops and grain responded to increasing superphosphate drilled with the seed. In each experiment there was a common relationship between yield and P content in lupin tissue, regardless of how the superphosphate was applied, suggesting that lupins responded solely to P, and other factors did not alter yield. We recommend that farmers band superphosphate 5-8 cm below the seed while sowing, rather than continue the present practices of either drilling the fertiliser with the seed, or topdressing it before sowing.
Chemical control of loose smut (Ustilago segetum var. tritici) of barley and the effects of cultivar and environment on disease incidence
Authors: Loughman R , Speijers EJ , Thomas GJ , Ballinger DJ
Published: March 2005

The reasons for an increase in barley loose smut in high rainfall areas of Western Australia were investigated in field trials from 1986 to 1988 by examining the effects of environment, cultivar and adequacy of chemical control. Disease was 4-18 times greater in 2 seed lines produced in very high rainfall areas (>750 mm/year) compared with that produced in high (450-750 mm/year) or low (<325 mm/year) rainfall areas. The effectiveness of 5 fungicide seed treatments was assessed. No fungicide seed treatment controlled disease completely. Triadimenol at 225 mg a.i./kg and carboxin at 940 mg a.i./kg were most effective, providing 93-96% disease control. Treatments were significantly (P<0.01) less effective in high rainfall areas of Western Australia. Barley cultivars released recently in Western Australia were found to be susceptible to loose smut; we suggest that the replacement of the moderately resistant Dampier with these cultivars has contributed to an increased incidence of disease.
Evaluation of seed, stem and soil applications of procymidone to control white rot (Sclerotium cepivorum Berk.) of onions
Authors: Porter IJ , Maughan JP , Towers GB
Published: March 2005

The effects of different methods of applying procymidone, either alone or combined, were evaluated for control of white rot (caused by Sclerotium cepivorum Berk.) in onions at 2 sites in Victoria.Field trials at Colac showed that seed treatments combined with sprays to the soil surface gave the most effective control of white rot, reducing disease from 78 to 16% and increasing yields from 5.7 to 14.6 t/ha in brown onions. Sprays applied to the soil surface at 2.5 kg a.i./ha had no effect on emergence and reduced disease incidence from 65.3 to 21.7%. Seed treatment at 25 g procymidone/kg seed delayed the onset of disease by 80 days and reduced disease incidence by 30%. The same treatment also reduced plant emergence by more than 27% and, therefore, did not increase yields. Dispersible granules (5 or 10%; at 2.5 kg procymidone/ha) were as effective as the soil sprays at sowing. Stem base sprays applied 11 and 19 weeks after sowing reduced disease incidence slightly but did not increase yields. Procymidone applied with bands of fertiliser 2 or 5 cm below the seed was not effective. Two formulations of procymidone, Sumisclex 500 (50% a.i.) and 275 Flocol (27.5% a.i.), were equally effective in controlling white rot. At Lang Lang, root-dips of 14-week-old seedlings in 5 g procymidone/L reduced white rot in transplanted white globe onions. Procymidone concentrations of 0.05-50 g a.i./L applied for periods ranging from 2 s to 30 min had no effect on plant establishment in a glasshouse.
Investigation of various gases, pH and redox potential in mushroom composting Phase I stacks
Authors: Miller FC , Macauley BJ , Harper ER
Published: March 2005

Investigations of hydrogen sulfide and ammonia concentrations, pH and redox potential were carried out within Phase I mushroom composting stacks in conjunction with measurements of temperature and oxygen concentrations. Gypsum-derived sulfate supported significant microbial activity by sulfate-reducing bacteria in anaerobic core areas. Ammonia concentrations up to 800 ppm were strongly associated with pH values up to 8.8 in aerobic stack areas. Anaerobic areas had pH values of 5-7, with little or no ammonia. Redox potential generally agreed with oxygenation history, with stacks exhibiting reducing conditions overall and with potential rising with compost maturity. Anomalously negative redox potentials in aerobic, outer stack areas were associated with actinomycete colonisation. Physical factors such as temperature, oxygen availability and water potential, which determine microbial and chemical activity in stacks, are distributed very unevenly, both spatially and temporally.
Effects of pesticides on the yield and production patterns of three standard and six hybrid strains of cultivated mushrooms in New South Wales
Authors: Clift AD , Terras MA
Published: March 2005

The yields and production patterns of 9 commercial mushroom strains, consisting of 6 hybrid strains and 2 standard strains of Agaricus bisporus and 1 of A. bitorquis, were examined when insecticides, fungicides and nematicides were used in various combinations in the casing layer. As far as could be determined, there were no insects, nematodes or diseases present in damaging numbers. The strains responded differently to the pesticide treatments, from yield decreases to increases compared with the untreated control. The inclusion of benomyl increased the yield of 4 hybrid strains tested with diazinon + maldison. For the same 4 strains the addition of the nematicide phenarniphos to diazinon + maldison + benomyl resulted in a yield higher than diazinon + maldison but a lower yield than diazinon + maldison + benomyl. Regardless of the effect on the yield, the insecticide treatments delayed production of sporophores, but this was compensated by greater production later, resulting in yield increases in 6 of the 9 strains tested.
Wool growth responses to DL-methionine administration and factors affecting the value of supplementation
Authors: Stephenson RGA , Suter GR , Howitt CJ
Published: March 2005

Wool growth responses to methionine administration were assessed using Peppin Merino wethers on various planes of nutrition. In experiment 1, sheep were fed 700 g/day of lucerne pellets to maintain liveweight. DL-methionine (5.8 g) administered subcutaneously resulted in 0.29 mg/cm2.day (36%) more wool (P<0.01) and a 2.5 �m (15.2%) increase in fibre diameter (P<0.05). In experiment 2, two levels (700 and 1400 g/day) of lucerne pellets were offered, with and without methionine administered subcutaneously (5.8 g). Main treatment analysis indicated a significant (P<0.01) effect of nutrition on wool growth and fibre diameter, with no effect of methionine, except for a reduction (P<0.05) in liveweight gain. Methionine administration was associated with a non-significant increase (39%) in wool growth for the 700 g diet and no change for the 1400 g diet. In experiment 3, two levels (1.75 and 2.5 g/day) of methionine were infused (4 h daily) when sheep were fed a submaintenance ration of Rhodes grass chaff, supplemented with nitrogen and sulfur. Significant (P<0.05) wool growth responses at both levels of methionine infusion were similar, with absolute (0.21 and 0.23 mg/cm2.day) and percentage (52 and 58%) increases for 1.75 and 2.5 g/day methionine treatments, respectively. Methionine administration only increased wool production at nutritional levels of liveweight maintenance or below when wool growth values for control treatments were 0.63,0.59 and 0.40 mg/cm2.day for experiments 1, 2 and 3. Fibre diameters of sheep in untreated groups were 16.4 and 18.8 pm for experiments 1 and 2. These wool growth and fibre diameter values are 25-40% below what might be expected for this strain of Merino. The values of positive correlations between wool growth and fibre diameter were increased with increased nutrition and the administration of methionine in experiment 2. This result and the nil response at high basal wool growth, together with the low potential net return on the cost of methionine, suggest that the use of methionine could be unprofitable.
Control of Pleiochaeta setosa diseases of lupin using seed and fertiliser applied fungicides
Authors: Loughman R , Sweetingham MW
Published: March 2005

Control of Pleiochaeta setosa diseases of lupins was compared in 8 field experiments using Rovral (iprodione) and Sumisclex (procymidone) as either seed dressing or fertiliser-applied treatments. Seed-dressing application was more effective than fertiliser application for control of brown spot. Rovral and Sumisclex provided very similar control of brown spot in most comparisons, but Sumisclex occasionally provided significantly better control. Pleiochaeta root rot was controlled by Rovral seed treatment at 1 location and by all Rovral and Sumisclex treatments at a second location. When used at 1 location, Armour (flutriafol) on superphosphate provided significant control of brown spot but not pleiochaeta root rot. Fungicide seed treatment did not reduce Phomopsis leptostromiformis stem lesioning. Significant yield improvement following fungicidal control of P. setosa occurred in 4 experiments.
Lack of control of phytophthora root in lucerne (Medicago sativa) by foliar applications of phosphorus
Authors: Lowe KF , Ryley MJ , Bowdler TM
Published: March 2005

Application of phosphonate was investigated as a means of controlling phytophthora root rot (Phytophthora megasperma f. sp. medicaginis) in lucerne (Medicago sativa). Foliar sprays of the chemical at rates of 2, 4 and 8 g/L did not improve the persistence or dry matter production of susceptible or resistant cultivars of lucerne, despite a small reduction in the degree of damage inflicted on lucerne plants by a severe epiphytotic of the disease. Regular monthly applications gave no better control than single applications at establishment or at the time of the development of an epiphytotic. It is concluded that phosphonate is not efficacious in controlling phytophthora root rot in lucerne and will not improve the performance of susceptible cultivars in high risk situations.
The relationship between incidence of infection by the take-all fungus (Gaeumannomyces graminis var. tritici), rainfall and yield of wheat in South Australia
Authors: Roget DK , Rovira AD
Published: March 2005

. This paper describes results obtained from an 8-year field trial on a calcareous sandy loam in South Australia. Different crop rotations resulted in varying percentages of plants with take-all [caused by Gaeumannomyces graminis var. tritici (Ggt)]. The results demonstrated that in a wheat-grass/medic pasture rotation, take-all caused an average annual yield loss in wheat of 29%. These yield losses were strongly correlated with disease incidence and rainfall in September (r2 = 0.91, P = 0.07) but only moderately correlated to disease incidence alone (r2 = 0.44, P = 0.09). The level of early infection (at 10 weeks) by Ggt was influenced by spring rainfall in the previous season. A regression model was developed to predict the incidence of take-all in a wheat crop from the incidence of take-all and the August-September rainfall the previous season (r2 = 0.96, P = 0.007) for a wheat-grass/medic pasture rotation (successive host plants).
Feed requirements for maintenance and growth of one-year-old Angus steers selected for either fast or slow yearling growth rate
Authors: Herd RM , Speck PA , Wynn PC
Published: March 2005

The efficiency of feed utilisation for maintenance and growth at 1 year of age was examined in 11 steers from each of 2 lines of Angus cattle selected for either fast (high line) or slow (low line) average daily gain to 1 year of age. The steers were established on a range of dietary energy intakes for 2 trials, each of 3 weeks duration. Fasted liveweights (LW) were measured at the start and end of each trial. Body fat was estimated at the end of the first trial. At the start of the experiment the high line steers were heavier (P<0.001) than the low line steers (278 v. 203 kg). The high line steers required more (P<0.001) feed per day [48.0 v. 39.3 MJ metabolisable energy (ME)] to maintain their greater LW but required less (P = 0.05) feed to sustain each kilogram of this LW (0.174 v. 0.192 MJ ME/kg LW) and, so, were more efficient. There was no difference in the efficiency of feed use for gain in LW (0.042 v. 0.040 kg LW/MJ ME.day). However, after adjusting feed intakes for the different mature sizes (A) of the 2 lines, there was no difference in the biological efficiency of feed use for either maintenance (0.369 v. 0.359 MJ ME/kg A0.73) or gain (5.45 v. 4.37 kg LW/MJ ME.kg A0.73). These results suggest that divergent selection for growth rate in this study has produced different-sized animals whose ability to convert feed to gain in LW has not been altered.