bluuebunny/crossref_metadata_2025 huggingface dataset:
Establishment of serradella by sowing either pod segments or scarified seed under a wheat crop
Authors: Bolland MDA
Published: March 2005

Seed of Pitman serradella, an annual pasture legume grown on sandy soils in Western Australia, is produced in pods which segment shortly after maturity and drop on to the ground. Farmers harvest pods before they segment, i.e. when >90% of the seed is usually impermeable (hardseeded). At two sites the persistence of Pitman was compared when it was sown under a wheat crop either as podded, or as dehulled and scarified seed. Less than 5% of the podded seed emerged under the crop, but 60-80% emerged in the first pasture after the crop and established reasonable densities in the second year pasture. Most of the dehulled and scarified seed emerged under the crop, but the serradella failed to persist in subsequent years.
Nutrition of irrigated crops on an alkaline brown clay soil at Trangie, New South Wales. 2. Wheat
Authors: Muldoon DK
Published: March 2005

In a field nutrient-omission experiment, nitrogen, phosphorus, potassium, sulfur and zinc were sequentially omitted from a 'complete' fertiliser applied to irrigated wheat on an alkaline brown clay soil. Wheat forage and grain yields were recorded for 3 years following this single application. The chemical composition of forage and grain was determined. A second experiment elucidated the response to nitrogen fertiliser after 2 years of wheat or fallow. Deficiencies of phosphorus and nitrogen were evident in the second and subsequent crops. Forage and grain yields were reduced in the absence of these elements as were the respective concentrations of phosphorus and nitrogen in the forage and grain. The omission of zinc fertiliser reduced the concentration of zinc in the grain but not the grain yield. Omitting sulfur led to lower grain yields in the second year. Both sulfur and nitrogen were required to achieve maximum grain nitrogen and sulfur contents. The response to nitrogen fertiliser peaked at 130 kg/ha N after a fallow. After continuous wheat, however, over 200 kg/ha N was required for maximum yields. A positive tillering response to nitrogen accounted for much of this grain yield response. Grain nitrogen contents remained low until 100kg/ha N was applied.
Effects of cutting and cold-storage of parent canes on cane production of raspberry
Authors: El-Zeftawi BM , Goubran FH , Richards JG
Published: March 2005

Parent canes of Willamette raspberry produced more vigorous canes than those of Glen Clova although the latter was less prone to bud failure in the first year. Reducing the length of the parent canes encouraged cane production and lowered the incidence of bud failure. Freshly dug plant material had more canes and less bud failure than those stored at 2�C, particularly when planted during June-July. For all treatments, the percentage of fruiting canes was 2-3 times higher in the second growing season than in the first, despite the total number of canes being less.
Effects of cottonseed meal and cereal grain supplements on intake and utilisation of alkali-treated wheat straw by cattle
Authors: Spragg JC , Kellaway RC , Kempton TJ
Published: March 2005

Effects of cottonseed meal and cereal grain supplements on intake and utilisation of alkali-treated wheat straw were studied with 45 Friesian heifers (250 kg liveweight) in individual pens. Responses were measured in terms of feed intake and growth rate over 60 days. The basal diet fed ad libitum was coarsely milled wheat straw which was alkali-treated, sprayed with a solution containing urea, sulfur, copper and cobalt and sprinkled with dicalcium phosphate. Animals were also fed 800 g/day of 1 of 5 supplements: cottonseed meal (CSM), whole barley (WB), cracked barley (CB), ammonia-treated whole barley (NB) and extruded barley (EB). Intakes of the basal diet did not differ significantly between groups. Digestible organic matter in dry matter (%) was 53.1, 51.7, 47.2, 47.7, and 48.7 with supplements CSM, CB, WB, NB and EB, respectively; values for CSM and CB were significantly higher than for the other supplements (P< 0.05). Liveweight gains were 891,761,639, 657 and 784 g/day with the respective supplements, and did not differ significantly between CSM, CB and EB. We concluded that CSM did not stimulate intake of roughage more than supplements of barley grain, and that growth of the cattle was limited primarily by intake of energy.
Selecting for nutritive value in Digitaria milanjiana. 1. Breeding of contrasting full-sib clones differing in leaf digestibility
Authors: Hacker JB
Published: March 2005

Nineteen F1 families were produced by pair-crossing 7 stoloniferous genotypes of Digitaria milanjiana. Progenies and parents were grown as spaced plants (0.5 by 0.5 m microswards) and plucked samples were taken from vegetative regrowth in 2 successive seasons for estimation of digestibility using the in vitro cellulase method. Stolon number, herbage yield (one, 9-week regrowth), flowering date and leaf width were also assessed. Parental clones differed significantly in plucked sample digestibility (range 4.1 units) and there was no significant clonexyear interaction. Heritability, based on parent-progeny regression, was 0.86. The occurrence in progenies of a low percentage (4.9%) of genotypes with plucked sample digestibility significantly higher than that of the higher parent suggested that genetic improvement of plucked sample digestibility may be possible. However, such segregates did not occur in the progeny of high digestibility parents. Digestibility of plucked samples was not correlated with any of the agronomic attributes measured. This, together with the high heritability for stolon number (h2 = 0.86) indicates that it is feasible to breed a genotype of D, milanjiana with high yield, high leaf digestibility and vigorous stolon development for clonal propagation. Genotypes with a mean plucked-sample digestibility of >70.0% occurred in 11 families. For these families highest and lowest digestibility genotypes were further sampled; only the top 2 fully expanded leaves were analysed. Conclusions derived from plucked samples were confirmed, showing that full-sibs differed genetically in leaf digestibility. Three pairs of full-sibs, which differed in leaf digestibility by 5.0-7.2 units, were selected for in vivo and physiological comparison.
The use of epidermal hairs of the legume Siratro recovered in the faeces to estimate the proportion of Siratro in the diet of ruminants
Authors: Jones RJ , Slater J
Published: March 2005

The epidermal hairs of the tropical pasture legume Macroptilium atropurpureum cv. Siratro number 3-5x 106/g DM; the hairs pass through the digestive tract of sheep and cattle undigested. A method for counting the hairs in Siratro samples and in faeces from animals which had consumed diets containing Siratro was developed. This consisted of digesting 0.5 g of faeces in sodium hypochlorite solution and counting the hairs present in subsamples of the digest under a microscope. Compared with stems, leaves had more than twice as many hairs per unit of dry weight. Hair density varied with age of regrowth, but this was probably a function of growing conditions rather than age per se. At each regrowth age, hair density on leaves was strongly related to density on stems. In pen feeding studies with sheep, the percentage Siratro in the diet was linearly related to the epidermal hair counts in the faeces. The technique was capable of detecting as little as 1% Siratro in the diet. Mean recovery of ingested hairs from the faeces of sheep fed different amounts of Siratro was 100.2%. In a field study, the mean percentage Siratro in extrusa samples collected from oesophageally fistulated cattle at 3 times of the year was linearly related (r=0.989, P < 0.01, r.s.d.=5.3) to the mean hair counts in the faeces of cattle continuously stocked at 2 rates on the same Siratro-setaria (Setaria sphacelata) pastures. In order to accurately estimate the Siratro component in the diet of grazing animals it is essential that the hair density of the Siratro eaten and the digestibility of the diet are measured in addition to the hair density of the faeces. Hair numbers in the faeces may be adequate to determine the pattern of selection for Siratro throughout the year. The use of indigestible epidermal hairs as inert markers in grazing studies is discussed.
Residual values of zinc sulfate and acidifying (elemental) sulfur for rice on the alkaline Cununurra soils of the Ord Irrigation Area, Western Australia
Authors: Chapman AL , Cellier KM
Published: March 2005

The residual values of zinc sulfate and acidifying (elemental) sulfur (S) for rice on Cununurra clay were investigated at Kimberley Research Station, near Kununurra in the Ord Irrigation Area, Western Australia. Successive crops were grown on 2 sites showing different degrees of zinc (Zn) deficiency according to visual symptoms. Despite the marked response to Zn fertiliser shown by the first crop of IR665-24-1 rice on the more deficient site (previously fallow for 12 months) there was no significant yield response to applied Zn in the third crop. On the less Zn deficient site (previously under weeds for several years), IR661-1-170-1-3 rice showed no response to Zn fertiliser although transient symptoms occurred in the first and second crops. Continuous cropping per se apparently reduced the severity of Zn deficiency on both sites, thus negating attempts to estimate the residual value of Zn fertiliser. The 2 sites were not distinguishable by the EDTAammonium carbonate soil test for Zn. Extractable Zn increased with increasing level of Zn fertiliser, but plant response was not related to extractable Zn. Application of elemental S (1-4 t ha-1) had no effect on extractable Zn levels before sowing of rice. Increased rice yields due to acidifying S were confirmed, but the residual effects did not extend beyond the fourth crop. In each of the 3 seasons following S application, the yield of IR661-1-170-1-3 increased by 0.3-0.6 t ha-1 but, at current prices, the use of S as a soil ameliorant for rice in the Ord Irrigation Area would be uneconomic.
Effect of time of sowing on oil content, erucic acid and glucosinolate contents in rapeseed (Brassica napus L. cv. Marnoo)
Authors: Sang JP , Bluett CA , Elliott BR , Truscott RJW
Published: March 2005

The effect of time of sowing on the oil and meal quality of rapeseed (Brassica napus L. cv. Marnoo) was investigated at Werribee, Victoria, during 198 1 and 1982. In both years oil content declined with later sowing but the proportion of erucic acid in the oil was unaffected by sowing time. In contrast, later sowing increased the glucosinolate content of the seed meal, with July-September sowings exceeding the Canola standard. This increase was due primarily to the increased content of 2-hydroxybut-3- enyl glucosinolate (progoitrin).
Liver damage and the liveweight changes in Merino wether weaners grazing mixed crops of oats and sweet narrow-leafed lupins
Authors: Morcombe PW , Croker KP , Allen JG
Published: March 2005

Merino wether weaners were grazed on mixed crops of oats and sweet lupins at 3 stocking rates (15, 30 and 60 sheep/ha), pure lupins (60 sheep/ha) or pastures (7.5 sheep/ha) with and without an ad libitum ration of an oat-lupin grain mix in 2 experiments. Changes in liveweights and liver damage due to lupinosis were measured. In experiment 1, when grazing commenced in late January 1982, the weaners grazed on the mixed crops at 15, 30 and 60 sheep/ha gained 4.8 kg over 91 days, 2.9 kg over 43 days and 1.2 kg over 43 days, respectively, while those on the pure lupins gained 0.7 kg over 14 days. These liveweight gains were all less (P<0.05) than the 10 kg increase over 70 days by the weaners on pasture which received the ad libitum supplement of oat-lupin grain (about 2.2% N). Liver damage developed at a slower rate in the sheep on the mixed crops. In experiment 2, when grazing commenced in late November 1983, the weaners grazed on the mixed crops at 15,30 and 60 sheep/ha gained 1 1.3 kg over 70 days, 6.2 kg over 42 days and 3.5 kg over 28 days, respectively, while those on the pure lupins gained 3.4 kg over 28 days. These liveweight gains compared with a 12.5 kg gain over 84 days by the weaners on pasture which received the ad libitum supplement of oat-lupin grain (about 2.60%N). There was less Phomopsis leptostromiformis on the lupin stems in this experiment and the sheep livers were not as badly damaged as in the previous experiment. The development of liver damage was again delayed in the weaners grazed on the mixed crops. It was concluded that Merino wether weaners can increase liveweights when grazed on mixed crops of oats and sweet lupins. The amount of increase depends on the grain available to the sheep and the degree of lupinosis-associated liver damage suffered by the sheep. Grazing mixed crops reduces the development of lupinosis.
Yield losses caused by Colletotrichum gloeosporioides in three species of Stylosanthes
Authors: Davis RD , Irwin JAG , Shepherd RK , Cameron DF
Published: March 2005

Yield losses from the fungal disease anthracnose, caused by Colletotrichum gloeospovioides, were estimated for 3 species of Stylosanthes grown in northern Queensland. Naturally infected control plots of S. scabra cv. Fitzroy, S. hamata cv. Verano and S. guianensis cv. Graham were compared with plots protected by 3 benomyl spray treatments designed to restrict anthracnose development to 0, 25 and 50% of the level sustained in the unsprayed control plots. Following initial infection in early February 1984, disease incidence and severity in Fitzroy and Verano reached a maximum during early March. This rapid build up of disease was associated with a period of sustained wet weather. Graham only became infected much later in the season as the plants matured, and sustained severe anthracnose lesions on both leaves and stems even though weather conditions appeared unsuitable for an epidemic. Yield losses were severe in all 3 cultivars. Average dry matter yields of the unsprayed controls were only 21.6, 66.7, and 53.5% respectively of the yields of the disease free plots for Fitzroy, Verano and Graham. Corresponding seed yields were 15.6, 48.9 and 42.5% respectively. Highly significant negative correlations were found between dry matter and seed yields of the 3 species and the incidence and severity of anthracnose disease.
Persistence of seed produced from single seed crops of subterranean clover on sandy soils near Esperance, Western Australia
Authors: Bolland MDA , Collins WJ
Published: March 2005

The number and weight of seeds per unit area, and weight per seed were measured for single seed crops of 6 subterranean clover cultivars grown as dense single strain swards on sandy soil near Esperance, W.A. In the sowing year, weight and number of seeds and weight per seed varied with cultivar and year of sowing. In the regeneration years, weight of seed decreased by about 60% between the first and the second year (range 50-75%, depending on cultivar and year of sowing), by a further 27% between years 2 and 3 (range 20-3g%), and a further 3.2% between years 3 and 4 (range 1.7-5.0%). The relative decrease in numbers of seed per unit area, to year 4, followed almost identical trends. Individual seed weight was constant for each cultivar sown in the same year, with the exception of 1 experiment sown in 1982 when seed collected in the next 2 regeneration years was 1.1-1.4 times as heavy as seed produced in the sowing year. In the sowing year, seed collected about 1 week after the clover had dried off contained less than 4% moisture (dry weight basis) and most of the seed were impermeable (hardseeded).
Response of wheat cultivars to early post-emergence herbicides containing MCPA (2-methyl-4-chlorophenoxyacetic acid)
Authors: Leys AR , Hinkley RB , Fisher JA
Published: March 2005

In southern New South Wales in 1978 and 1979, the responses of 10 spring wheat cultivars to early post-emergence applications of MCPA, bromoxynil plus MCPA, and dicamba plus MCPA, were evaluated. The herbicides were applied at the rate recommended by their manufacturer (1x), and at 3 times this rate (3x). Cultivars differed in their responses to these treatments and herbicide tolerance was related to the stage of development of the apical meristem of the main tiller at the time of spraying. Olympic, Shortim and Egret were the most sensitive cultivars and their grain yield, averaged over rate and year, was reduced by 33, 19, and 15% respectively. Songlen, Jabiru and Durati were the most tolerant cultivars. Songlen was not affected by any herbicide, even when the 3x rates were used, while the grain yields of Jabiru and Durati were only reduced in 1 year, and then only by the 3x rate of dicamba plus MCPA. The remaining cultivars, Kite, Gamenya, Condor and Lance, were intermediate in their response to these herbicide treatments. Delaying the application of 1 of these herbicides, dicamba plus MCPA, until spikelet initiation, minimised yield reductions. Correlations between visual assessment of crop damage and grain yield reduction varied between cultivars and between herbicides.
Effects of dicyandiamide (a nitrification inhibitor) on leaching of nitrogen and growth of cereals
Authors: Mason MG
Published: March 2005

Dicyandiamide (DCD) was tested as a nitrification inhibitor with urea in 10 field experiments (ammonium nitrate was included in 2 of them) in 3 years on sites where leaching of nitrogen was a potential problem. The investigations included different rates and times of nitrogen application. At 1 site in 1982 and 2 in 1983 the soil was sampled to 30cm throughout the season. Nitrification of ammonium nitrogen was delayed by DCD (applied as a mixture with urea and supplying 10% ofthe nitrogen in the mixture) by up to 30 days compared with untreated urea and reduced the danger of nitrogen leaching. Early sampling at the 1982 site showed increased uptake of ammonium nitrogen and decreased nitrate nitrogen in wheat plants receiving DCD-treated urea compared with those receiving untreated urea. This confirmed that DCD inhibits nitrification. The only significant (P<0.05) grain yield increase from DCD was a 22% increase from an application of nitrogen at sowing on a particularly highly leaching soil. DCD significantly (P < 0.05, P < 0.01) reduced grain yield (7 and 8%) and vegetative yield (1 3 and 9%) at 2 sites. DCD increased vegetative yield by 16% at 1 site (not the same site as the grain yield increase). In 2 of 3 experiments plant dry matter production (up to 11 weeks after sowing) was significantly (P < 0.05 to P < 0.001) reduced (up to 30%) by DCD application. The final value of the use of DCD will depend on the balance between the benefit in preventing nitrogen losses by leaching at a particular site and the harm caused by suppressing early plant growth.
Sowing-date responses of early maturing indeterminate soybean genotypes in northern New South Wales
Authors: Rose IA
Published: March 2005

The development of new cultivars has provided impetus for soybean (Glycine max) production in northern New South Wales to expand into dryland cropping areas. These new cultivars differ from the traditional irrigated types by being indeterminate and maturing 3-4 weeks earlier. There is no information on the response of this type of cultivar to agronomic factors such as sowing date. However, knowledge of the response to sowing date is of particular importance as it allows producers to decide whether or not to take advantage of good seedbed moisture outside the most favoured range for sowing date. This study utilised irrigated conditions to examine the phenological and yield potential responses to sowing date of 6 early maturing genotypes, including the recently released cultivars. For sowing dates from early November to December the phenological responses were minor and unlikely to influence sowing date decisions, but yield responses varied among genotypes. The recently released cultivars Farrer and Valder showed similar yielding ability across sowing dates from early November to early December. However, the other 4 genotypes (Williams, Calland, Bill 55, Witch 101) showed a marked yield depression with early sowings. Thus choice of cultivar is important when deciding on sowing dates, and tests of sowing date response are necessary for cultivars released for dryland production in the future.
Pathogenicity of fungi isolated from Cicer arietinum (chickpea) grown in north-western Victoria
Authors: Bretag TW , Mebalds MI
Published: March 2005

Several diseases, Botrytis grey mould, Fusarium wilt, Rhizoctonia root rot, Phoma blight and Sclerotinia stem rot, affecting chickpea grown in north-western Victoria were identified. Although the diseases Fusarium oxysporum and Phoma medicaginis) were are caused by different fungi, they can all cause chickpea plants to wilt and are therefore easily confused. Some pathogens (Ascochyta pisi, Botrytis cinerea, seed-borne and seed transmission may be an important factor in their spread. Pathogenicity studies showed that chickpea plants were also susceptible to common fungal pathogens of field peas and medics.
Effect of live weight gain before or during pregnancy on mammary gland development and subsequent milk production of Australian Holstein-Friesian heifers
Authors: Valentine SC , Dobos RC , Lewis PA , Bartsch BD , Wickes RB
Published: March 2005

Two groups of 90 Holstein-Friesian heifers were grown at 0.60 kg/day liveweight gain up to 110 kg liveweight and then grown at either 0.18, 0.62 or 0.94 kg/day for 15 weeks commencing at about 4 months of age. All heifers were then grown at 0.59 kg/day, except for a period of 15 weeks commencing at 4.5 months of pregnancy when the heifers grown at 0.62 kg/day from 110 kg liveweight were grown at either 0.22, 0.59 or 1.06 kg/day. Groups of heifers were milked or slaughtered either at mating (300 kg liveweight) or 2 weeks after calving and the chemical and histological composition of the udders determined. Mean daily yields (kg) of milk fat and solids not fat (SNF) during the first 10 weeks of the first lactation were significantly (P< 0.05) higher for heifers grown at 0.18 (0.70, 1.58) and 0.62 kg/day (0.61, 1.42) than for those grown at 0.94 kg/day (0.49, 1.19) before mating. During the complete first lactation, there was a trend for higher milk fat yield (kg) and concentration (g/kg) of heifers grown at 0.18 kg/day (122, 44) compared with those grown at 0.62 (119, 41) and 0.94 kg/day (114, 41) before mating. During the first 10 weeks of the second lactation, the mean daily yield (kg) of milk fat was significantly (P < 0.05) higher for the heifers grown at 0.18 kg/day (0.79) than for those grown at 0.62 (0.68) and 0.94 kg/day (0.74) before first mating. Rate of liveweight gain of the heifers during pregnancy had no significant effect on the production of milk or milk components. There were generally no significant differences in the composition of the udders from heifers grown at different rates of liveweight gain before mating or during pregnancy. It was concluded that, although there were no detrimental effects of rearing heifers at 0.18 kg/day before mating on production during the first lactation, the economic implications of at least a 6-month delay in commencement of lactation compared with heifers reared at a rate of liveweight gain of 0.62 kg/day must be considered.
The energy value of whole oats grain in adult wether sheep
Authors: Margan DE , Graham NM , Searle TW
Published: March 2005

Samples of Cooba and Coolabah oats were chosen on chemical analysis to represent relatively high and low quality grain. Each was evaluated by measuring energy, nitrogen and carbon balances in 4 adult sheep at several levels of feeding and during starvation. The Cooba contained, on a dry matter (DM) basis, 14% crude protein (CP), 23% cell wall constituents (CWC) and 19.1 MJ/kg gross energy (GE); the Coolabah had 10% CP, 31% CWC and 19.6 MJ/kg. With ad libitum feeding, respective DM intakes were 1.4 and 1.8 kg/day (3.3 and 4.4 times maintenance) giving daily retentions of 6.6 and 8.2 MJ and 6.2 and 8.0 g nitrogen. The availabilities of the gross energy of the Cooba at maintenance were 85% digestible energy (DE), 71% metabolisable energy (ME) (13.6 MJ/kg DM), 59% net energy (NE); when assessed as a production supplement, the values were 79,74 and 38% respectively. The results for Coolabah were 76% DE, 68% ME (1 3.3 MJ/ kg), 53% NE (maintenance); 64% DE, 6 1% ME, 36% NE (production supplement). It is apparent from the present and previously published results that the GE and ME/DE values of oats are higher than commonly supposed. Furthermore, although protein and fibre content indicate the relative digestibilities of feeds, they are not a good guide to relative NE values nor to attainable production in terms of either energy or protein.
Incidence of Phomopsis phaseoli (Desm.) Sacc. in crops and seed of soybean in New South Wales
Authors: Stovold GE , Francis A
Published: March 2005

The pod and stem blight and seed decay fungus Phomopsis phaseoli was detected in soybean crops in coastal districts of New South Wales as a symptomless infection in the lowest petioles at flowering. Up to 90% of petioles from a second year crop yielded the fungus compared with 17% from a first year crop. Similar effects of paddock history were evident during pod fill when 43% of pods from a first year crop were infected compared with 76% in a second year crop. Visible symptoms of infection only appeared after crops reached harvest maturity. Crops in the North West of the state were infected at a much lower level. As in coastal districts the highest levels of infection occurred in fields which had been sown previously to soybeans. Only negligible levels of infection were detected in crops grown in the Riverina district. Only seed from coastal crops carried significant infection with P. phaseoli. The level of infection varied within and between seasons and was determined by prevailing climatic factors, especially atmospheric humidity and rainfall during pod fill and after maturity. Humidity and rainfall are greater for coastal than for inland districts, but prevailing temperatures in coastal and inland districts are only slightly different.
Effects of tillage and straw mulches on take-all of wheat in the Northern Wimmera of Victoria
Authors: Kollmorgen JF , Ridge PE , Boer RFde
Published: March 2005

In 4 trials in the Northern Wimmera of Victoria, the incidence and severity of take-all of wheat caused by Gaeumannomyces graminis var. tritici were generally unaffected by tillage treatments (nil, chemical weed control; subsurface, blade plough and rod weeder; conventional scarifier, cultivator and harrows). At 1 site at 1 sampling time disease incidence was higher after conventional tillage than after subsurface tillage and at another site in 1 year out of 3, disease severity was greater after nil tillage than after conventional tillage. A stubble mulch of 4 t ha-1 of straw and burial at 5 or 10 cm reduced survival of the take-all fungus in wheat crowns.
Peanut yield and quality variation over harvest dates, and evaluation of some maturity indices in south-eastern Queensland
Authors: Shorter R , Simpson BW
Published: March 2005

Yield and quality variations across harvest dates in peanuts (Arachis hypogaea L.) grown under rainfed conditions in south-eastern Queensland in 1978-79 and 1980-81 were investigated. Free arginine percentage of kernels, kernel: hull weight ratio, shell-out percentage, mean individual kernel weight and kernel moisture percentage were monitored during crop development to assess their usefulness as indices of crop maturity. For the Virginia Bunch cultivar, kernel yield ranged from 1862 kg ha-1 at 133 days after sowing (DAS) to 2432 kg ha-l at 168 DAS in 1978-79 and from 687 kg ha-l at 201 DAS to 1618 kg ha-1 at 152 DAS in 1980-81. In both years kernel yield and crop value for Virginia Bunch exhibited bimodal responses to delayed harvesting, with maximum values being obtained at about 150 and 170 DAS. These responses tended to be associated with rainfall distribution and available soil moisture during flowering. None of the maturity indices investigated was sensitive enough to detect the 2 peaks for yield or crop value and therefore would be of no use in determining optimum harvest periods for Virginia Bunch. Red Spanish and White Spanish cultivars, evaluated in 1978-79, produced average kernel yields of 1777 kg ha-l and 1535 kg ha-1 respectively. For these cultivars, differences in yield and crop value over harvest dates were not significant. Although kernel yields did not increase after 133 DAS, the decline in free arginine percentage and the increase in the kerne1:hull weight ratio during the season suggested that these indices may be useful indicators of optimum maturity for spanish-type cultivars.
Comparison of phosetyl-Al, phosphorous acid and metalaxyl for the long-term control of Phytophthora root rot of avocado
Authors: Pegg KG , Whiley AW , Langdon PW , Saranah JB
Published: March 2005

Avocado trees affected by root rot caused by Phytophthora cinnamomi Rands recovered rapidly when given injections into the trunk of phosetyl-A1 or phosphorous acid. Injected trees had greater yields(47.9-67.5 v. 4.3 kg fruit per tree) and lower leaf chloride levels (0.8-2.4 v. 4.2%, w/w) than controls in the third season after starting treatment. Phosphorous acid residues (21-83 mg kg-1) were detected in fruit from injected trees. Metalaxyl applied to the soil twice each growing season successfully controlled root rot for the first 2 seasons, but there was a significant resurgence of decline symptoms after the third consecutive season of use.
An evaluation of classing Merino sheep for fleece rot susceptibility
Authors: Raadsma HW , Kearins RD , Bennett NW , Coy J , Watts JE
Published: March 2005

Two experiments were conducted to evaluate the ability of sheep classers to predict the susceptibility of Merino sheep to fleece rot. A total of 626 hogget ewes, from 15 genotypes known to vary in fleece rot susceptibility, were assessed by 3 classers in each experiment before fleece rot was induced. In all cases the classers were able to identify flocks resistant and susceptible to fleece rot (between-flock correlations between predicted and observed fleece rot susceptibilities ranged from 0.37 to 0.81). Some classers were also able to distinguish between resistant and susceptible sheep within a flock (within-flock phenotypic correlation between predicted and observed fleece rot susceptibilities ranged from 0.05 to 0.39). The potential role of sheep classers in relation to selective breeding against fleece rot is discussed.
Seed production of Trifolium subterraneum subsp. brachycalycinum as influenced by soil type and grazing
Authors: Bolland MDA
Published: March 2005

Twenty-six strains of Trifolium subterraneum subsp. brachycalycinum were assessed as potential pasture legumes on the 2 major soil types (neutral-slightly acid sandy [sandplain] soils and alkaline mallee soils) near Esperance, W.A. The pH (1 : 5, soil: water, w/v) of the top 10 cm of the sandplain soil was 6.3, and of the mallee soil, 8.2. In ungrazed swards on both soil types, subsp. brachycalycinum buried very few burrs but successfully produced seed in the unburied burrs in the dark, dense canopy of leaves. However, when the swards were grazed up to the start of flowering of the earliest flowering strains, subsp. brachycalycinum produced few burrs and little seed (0-47 kg/ha). By contrast, on the sandplain soils, subsp. subterraneum buried most of its burrs and produced much seed in both ungrazed (390-1050 kg/ha) and grazed (403-987 kg/ha) swards, whereas on the alkaline mallee soils, annual medics (Medicago spp.) produced much seed in unburied burrs in both grazed (506- 1050 kg/ha) and ungrazed (480-730 kg/ha) swards. Grazing may have exposed the developing unburied burrs of subsp. brachycalycinum to light, which is known to inhibit the development of burrs and seed. There was no relationship between seed yield and maturity for strains of subsp. brachycalycinum in ungrazed swards on both soils.
Comparison of twelfth rib and rump fat thickness measurements for predicting commercial beef yield in local market carcasses
Authors: Johnson ER
Published: March 2005

The abilities of 12th rib and rump fat thickness measurements to predict yield of saleable beef were compared in 40 Hereford steer carcasses weighing 173-235 kg. Saleable beef yield and fat trim were significantly related (P< 0.05) to all 4 fat thickness measurements studied, rump P8, rump sacral crest, 12th rib (all cold) and 12th rib (hot). Rump measurements generally, had slightly lower standard errors of estimate than the 12th rib measurements in predicting the weights and percentages of saleable beef yield and fat trim. Rump P8 predicted saleable beef yield weight, saleable beef yield percentage, fat trim weight and fat trim percentage with means (� s.e.) of 72.55 (� 6.69) kg, 70.52 (� 0.72)%, 7.23 (� 0.86) kg and 6.99 (� 0.68)%, respectively. Multiple regression analysis showed that the addition of hot carcass weight or cold carcass weight as the second regressor resulted in predictions of similar accuracy. Quadratic analyses indicated that weight or percentage of cuts, manufacturing trim, saleable beef yield and fat trim were linearly related to 12th rib (cold) fat thickness and to P8 fat thickness.
Autotoxicity is not implicated as a cause of a dying-centre growth pattern in lotononis
Authors: Thro AM
Published: March 2005

Stands of the highly nutritious, grazingtolerant pasture legume lotononis (Lotononis bainesil Baker) are often unreliable from year to year, in both favourable and suboptimal environments. An observed retreating pattern of lotononis growth resembles the effects of autotoxicity. A seedling germination experiment in the laboratory and an 11 -month greenhouse study of plant growth were conducted to determine if autotoxicity was a factor in the observed behaviour of lotononis. Treatments tested in these experiments were (i) soil infusions from sites where lotononis was growing vigorously, was dead or dying, or had never been grown; (ii) plant tissue infusions from healthy lotononis roots, healthy stolons and leaves ('shoots'), and dead and dying shoots; and (iii) lotononis roots and shoots mixed into and laid upon the soil in pots. In the seedling germination study, none of the treatments was significantly different (P<0.05) from a distilled-water control. In the plant growth study, plants in pots with lotononis roots mixed in the soil and lotononis shoots laid on the soil surface were significantly taller (5-12.8 cm height) and had significantly higher forage DM yields (10.02 g/plant) than plants in control pots (3-8.1 cm and 6.48 g/plant). The stimulating effect of lotononis plant residue on lotononis growth was probably due to additional nutrients and better water relations for plant growth. No evidence was found that autotoxicity is the cause of lotononis stand disappearance.
Mineral composition and responses to fertilizer of wheat grown on a limed and deep-ripped soil in north-eastern Victoria
Authors: Coventry DR , Morrison GR , Reeves TG , Hirth JR , Fung KKH
Published: March 2005

The nutrient requirements of wheat grown on a soil ameliorated with lime and deep ripping were studied in a field experiment over 5 seasons in northeastern Victoria. Phosphorus (P) fertiliser was required when this soil was limed, although the lime treatment may have increased P uptake (P x lime interaction). The nitrogen (N) concentration in wheat foliage was increased with both lime and deep ripping. It is likely that the availability of N will be the most important factor for sustaining high yields following soil treatment. Molybdenum (Mo) fertiliser (62 g Mo ha-1) increased grain yield in 2 seasons. Molybdenum fertiliser increased grain weight by an average of 4.4% over 3 years, and also the N content of grain in the absence of lime, indicating that a deficiency of available Mo in the soil was affecting the assimilation of N in the wheat. The magnesium (Mg) concentration in the wheat foliage was very low (0.07-0.10%) without soil treatment, but there was no grain yield response when Mg fertiliser (10.5 kg Mg ha-1) was applied in the absence of lime. Lime and ripping both resulted in big increases in manganese (Mn) concentrations in the foliage. Calcium (Ca) and copper (Cu) concentrations were little affected and zinc (Zn) was not affected by lime (Ca, 0.35-0 55%; Cu, 7-20 �g g-1; Zn, 50-60 �g g-1 at 50 days after emergence), and each nutrient appeared to be adequate for wheat. The concentration of Mn in the foliage was high without lime, but did not approach published figures for critical toxicity concentrations. Liming the soil greatly reduced the manganese concentration.
Evaluation of soybean breeding lines by examining their responses to sowing date and row spacing
Authors: Rose IA
Published: March 2005

Seven genotypes, including 5 in the final stages of cultivar selection, were evaluated for their phenological development, yield, seed size, oil concentration and protein concentration in response to changes in sowing date and row spacing over 3 seasons, 1982-83, 1983-84and 1984-85. Genotype x sowing date interactions were detected for both phenological development and yield, particularly with the cultivar Sxy 59. This genotype was most affected by temperature during the pre-flowering phase of early November sowings. It was lower yielding in November sowings but was the highest yielding genotype in January sowings. Its adaptation to January sowings was unexpected because this genotype also showed high photoperiod sensitivity and flowered and matured rapidly in the late sowings. With early sowing, yield of the other cultivars was equivalent, or superior to (P=0.05), that obtained with the recommended early December sowing date, depending on the season. Late sowings caused yield reductions of about 34%. Increases in yield with narrow rows (50 v. 100 cm) were significant (P = 0.05) in 1 season and averaged 5% overall. Genotypexrow spacing interactions were only detected in 1 season, but no genotype was superior to the standard cultivar, Forrest, in adaptation to narrow rows. Thus this study revealed genotype responses which would affect adoption of newly released cultivars. It was concluded that this type of study is valuable in the final stages of a selection program and that these studies should include both early and late sowing dates and be conducted over several seasons.
Production and economic returns from Merino weaner sheep subjected to four frequencies of anthelmintic administration in East Gippsland, Victoria
Authors: Barton NJ , McCausland IP
Published: March 2005

In East Gippsland. Victoria. 4 treatment groups, designated 'weekly' (W), 'high' (H), 'low' (L). and 'salvage' (S), each consisting of 3 subgroups of 10 Merino weaner sheep, were given different numbers of anthelmintic doses during 1978, 1979 and 1980. The doses were respectively 5 1, 5 1, 50 (W); 9,9, 12 (H); 3,4. 6 (L); and 1, 3, 2 (S). Both anthelmintics were administered according to the manufacturers' recommendations. Subgroups were grazed on separate 1 ha plots and rotated between plots within treatments at 2-week intervals in an attempt to eliminate between paddock differences. Sheep were replaced annually. These programs resulted in major differences in wool production and final liveweight between groups. Over the 3 years of the experiment, sheep dosed frequently grew heavier (P< 0.05) and produced more wool than - did sheep in the Land S groups. Mean final liveweights for the W, H, L, and S groups respectively were 53.6, 51.4.47.0, and 46.4 kg (l.s.d. [P= 0.051 = 3.5 kg). Corresponding figures for wool growth were 5.96, 5.62. 5.07, and 5.17 kg (l.s.d. [P = 0.051 = 0.60). Mortality in the W (5.6%) and H (22%) groups was also lower than in the L (18.9%) and S (27.8%) groups. The H group gave the highest economic return of $21.81 per sheep compared with $17.61 (W group), $16.3 1 (L) and $15.06 (S group). This advantage was maintained throughout a wide cost-price range. However. as both the W and H programs selected strongly for strains of nematodes resistant to anthelmintics. anthelmintic therapy alone cannot be relied upon for long-term parasite control.
Effect of gypsum and deep ripping on lucerne (Medicago sativa L.) yields on a red-brown earth under flood and spray irrigation
Authors: Taylor AJ , Olsson KA
Published: March 2005

Lucerne yield and soil responses to gypsum and deep ripping treatments were studied under flood and spray irrigation on 2 field experiments on a heavy red-brown earth. One application of gypsum at 12 t ha-1, both alone (G) and in combination with ripping to 0.6 m depth (GR) before sowing, resulted in sustained high yields of lucerne during a 4- year experiment. Under flood irrigation. there was no apparent yield advantage of GR treatments over G alone; yields averaged over 3 full production years were 143 and 175 t ha-1 for the control and the mean of the G and GR treatments, respectively. However, under spray irrigation, the mean annual hay yields for the control, G and GR treatments of 12.6, 17.3 and 19.4 t ha-1, respectively, were significantly different (P = 0.05). Yield was increased in proportion to the additional water made available to the crop resulting from deeper wetting of the ameliorated soils at irrigation. Increased water intake was attributed to increased conductance of the B horizon for water due to gypsum and/or deep ripping. Under flood irrigation. macroporosities measured at 0.30 m depth 4 years after treatment were higher in the ameliorated soils than the control but were no different between the G and GR treatments. In the spray experiment, the GR soils had consistently higher porosities and lower bulk densities than the G soils; the latter were no different to the control in these properties. The increased conductance is attributed to reduced clay swelling and the increased macroporosity of the B horizon due to ripping. Where measured on the flood experiment, the GR treatment promoted root growth in the R horizon. The longer-term stability of the ameliorated soils is discussed in relation to physico-chemical and biological mechanisms.
Reduced early growth of direct drilled wheat in southern New South Wales: causes and consequences
Authors: Cornish PS , Lymbery JR
Published: March 2005

In five experiments with wheat over 4 years on a red earth soil in southern New South Wales, direct drilling reduced plant population by an average of 15% and individual plant dry weight at 10- 11 weeks by an average maximum of 33% compared with sowing into a cultivated seed bed. The maximum reduction in dry weight per unit area averaged 44% (at tillering), but compensatory growth reduced this to 17% by anthesis. Time to emergence was not reduced and differences in plant weight soon after emergence were very small, which suggests that the effect on plant growth occurred only after emergence. Effects of direct drilling on soil surface (0- 10 cm) temperature and water content were not important factors reducing plant population or early growth but high soil strength seemed the most likely cause of reduced root extension in the direct drilled seedbed (0-1 5 cm). Reduced root extension had no direct effect on plant water relations or nitrogen concentration in leaves, but there was a small effect on phosphorus concentration. Reduced root growth appears to reduce shoot growth but the mechanisms require further study. The reduced shoot growth led to reduced preanthesis water-use. After anthesis direct drilled crops generally used more water and had higher leaf water potentials than crops in cultivated soil, leading to yield increases in 2 of the years with dry spring conditions. Only in a drought year (1982) was there evidence of direct drilling reducing the maximum depth of rooting and therefore reducing total water-use resulting in lower grain yield (8%). Overall, direct drilling increased grain yields by 2.4% (2.514 v. 2.576 t/ha) compared with conventional tillage, despite the large reduction in early growth.
Effect of soybean population density on soybean yield, nitrogen accumulation and residual nitrogen
Authors: Blumenthal MJ , Quach VP , Searle PGE
Published: March 2005

The effect of soybean population density on soybean yield, nitrogen accumulation and residual nitrogen was examined at Camden, N.S.W. (34�S.). In the first experiment, treatments were soybeans (cv. Ransom) at 50, 100, 200 and 400 x 103 plants ha-1; maize (cv. XL66); and a weed-free fallow. Total dry matter yields of tops and grain yields were highest at 200x 103 plants ha-1 (6214 and 3720 kg ha-1, respectively). The yield component most affected by population density was number of branches per plant, with values decreasing with increasing population density. The proportion of unfilled pods was highest at the highest population density. Total nitrogen (N) accumulation in the tops and in the grain was also at a maximum at 200x 103 plants ha-1. The rate of dry matter accumulation declined during pod filling at all population densities. N accumulation continued at high rates throughout the growing season except in the 400x 103 plants ha-1 population. There was a trend for residual dry matter and N in residues to increase with increasing population density. After grain and forage harvest of the first experiment, a crop of wheat (cv. Kite) was sown over the whole area to determine residual N available at anthesis and at maturity (experiment 2). The values of N accumulation in the wheat at maturity were 24 kg N ha-l for the maize treatment, 40-60 kg N ha-l for the soybean treatments and 69 kg N ha-1 for the fallow treatment. Grain yield and grain N followed the pattern of dry matter production and N accumulation at final harvest. The data suggest that soybean depletes soil N to a lesser extent than does maize. For the soybean treatments, there was a trend of increasing residual N at the 3 highest population densities (40-60 kg N ha-1). This was probably a result of an increase in N in leaf fall and in decaying tops and roots at the highest population density. The high value (57 kg N ha-l) at the lowest population density may be due to soybean plants at this density not using as much soil N as the other soybean treatments. No benefit in residual N was gained from planting soybeans at a density beyond the optimum for grain yield when residues were removed by forage harvesting.
Presence of deoxynivalenol in Australian wheat and triticale dash New South Wales Northern Rivers region, 1983
Authors: Tobin NF
Published: March 2005

Of 12 wheat samples from crops affected by head blight (caused by Fusarium graminearum) at harvest in the Northern Rivers region of New South Wales in November 1983, 11 contained up to 6.7 mg kg-1 (mean 1.8 mg kg-1) of the trichothecene mycotoxin, deoxynivalenol (DON, also known as vomitoxin). Grain feeds responsible for feed refusal and vomiting in a piggery in the region were found to contain up to 3.7 mg kg-1 of the toxin. Two triticale samples contained 9 and 11mg kg-1 of DON, but 2 barley samples were negative. A wide range of other wheat samples, principally representative of the New South Wales dryland wheat belt, were all, with 1 exception. found free of DON. Since DON can be produced in times of wet harvest, maximum limits for contamination of grains are recommended.