bluuebunny/crossref_metadata_2025 huggingface dataset:
Establishment and early growth after rice of subterranean clover (Trifolium subterraneum), Persian clover (T. resupinatum), balansa clover (T. michelianum), and white clover (T. repens)
Authors: Lattimore MAE , Beecher HG , O'Callaghan KL
Published: March 2005

Four temperate clovers were grown on a typical rice-growing soil in the Murrumbidgee Valley, New South Wales, to assess their establishment and early growth potential. Subterranean clover (Trifolium subterraneum var. yanninicum) cv. Trikkala, Persian clover (T. resupinatum) cv. Maral, balansa clover (T. michelianum var. balansae) cv. Paradana, and white clover (T. repens) cv. Haifa were sown immediately following a rice crop in autumn of 3 consecutive years. Seven sowing methods were compared, including combinations of surface or drill sowing with land preparation techniques commonly used in rice-farming systems. All cultivars established successfully. Trikkala had the best establishment on the basis of per cent seed sown in year 2, and equal best in years 1 and 3, although Paradana and Maral had higher plant densities at the sowing rates used. Paradana and Maral produced the highest dry matter yields and Haifa the lowest (P<0.05) in the growing period to mid-spring. Sowing method strongly influenced (P<0.05) both establishment and yield of clover. Sowing into a dense rice canopy before harvest severely restricted clover performance, while harvesting rice before sowing greatly improved (P<0.05) clover establishment and dry matter production. Establishment from surface sowing was generally more successful than from drill sowing, although yields with both methods were mostly satisfactory. Establishment and yields were highest after burning stubble, but this effect was variable and not always significant. Sowing after cultivation was not successful, especially in the 2 wetter years, due to poor seedbed preparation and waterlogging.
Effects of glyphosate, flupropanate and 2,2-DPA on Hyparrhenia hirta (L.) Stapf (Coolatai grass)
Authors: Lodge GM , McMillan MG , McCormick LH , Cook AS
Published: March 2005

Hyparrhenia hirta (L.) Stapf (Coolatai or Tambookie grass) has invaded roadside areas, travelling stock routes and grazing lands in northern New South Wales and southern Queensland. In these situations it is regarded as an undesirable species. There are no herbicides registered for use on this grass and little information is available on the long-term effectiveness of chemical control. Plots consisted of: 3 treatments imposed before herbicide application (untreated, mown and burnt); 5 herbicides [glyphosate, flupropanate (formerly tetrapion), 2,2-DPA, mixtures of glyphosatel flupropanate, and an untreated control]; 3 application rates for each herbicide; and 2 times of herbicide application (spring 1990 and autumn 1991). Herbicide effectiveness on Coolatai grass was measured by comparing reductions in dry matter and phytotoxicity up to 20 months after application. Six months after the spring application, yields were depressed (P<0.05) by herbicides (flupropanate applied at 4.4 kg a.i./ha and 2,2-DPA at 14.8 kg a.i./ha) and preapplication treatments (burnt plots sprayed with flupropanate at 1.1 and 2.2 kg a.i./ha), but their overall interaction was not significant. Ten months after autumn application, Coolatai grass yields were reduced (P<0.05) by herbicide, pre-application treatment and their interaction. Mowing and burning reduced (P<0.05) yields to 40 % of those in undefoliated plots. Yields were lowest (P<0,05) in mown (flupropanate 4.4 kg a.i./ha) and burnt (glyphosate, 2.16 and 4.32 kg a.i./ha, and flupropanate, 4.4 kg a.i./ha) treatments, where mean yields were <30% of the control. Seventeen and 20 months after application, none of the herbicide treatments gave 100% control of Coolatai grass. Glyphosate applied at 2.16 and 4.32 kg a.i./ha in autumn and flupropanate applied at 4.4 kg a.i./ha in autumn or spring were the most effective in the long term, reducing Coolatai grass dry matter yields by 70-80%.
Effect of inter-row spacing on the production of tagasaste and associated pastures
Authors: McGowan AA , Mathews GL
Published: March 2005

Tagasaste (Chamaecytisus proliferus (L. fil.) Link ssp. palmensis) was planted at 4 densities (2500, 5000, 10000, 20000 plants/ha with row spacings of 0.5, 1, 2 or 4 m). Plants were 1 m apart within rows for all densities, The tagasaste was harvested at about 6-monthly intervals in February and August over a 5-year period at a height of 0.5 m. Pasture growing between the rows was harvested at the same time to about 50 mm height. Growth per tree was reduced by increasing density, especially as the trees matured, but even after 4 years, yield per ha was more than 200% greater at the lowest density. Although there was an adverse effect of tagasaste density on pasture harvested (up to 32%), the total dry matter harvested in the final year was still 40% greater at the highest density of tagasaste.
Field evaluation of five clones of tissue-cultured bananas in northern NSW
Authors: Johns GG
Published: March 2005

The use of tissue culture (TC) could facilitate clonal changes and reduce pest and disease problems in the New South Wales banana industry. The performance of 5 clones of TC banana plants (Chinese Cavendish, 2 Mons Mari clones, and 2 Williams clones) and 1 clone propagated as suckers (Williams) was monitored in the field over 3 crop cycles. TC offtypes became evident during the first year. Overall 11% of field-planted TC plants were dwarf offtypes, and 8% were mosaic offtypes. Total offtypes in the field ranged from 1 to 63% for different clones. Dwarf offtypes produced 6% fewer (P<0.001) bunches than normal plants. Many mosaic offtypes died during the trial, and overall they produced 34% fewer (P<0.001) bunches than normal plants. Dwarf offtypes produced 41% of the marketable fruit of normal plants during the trial, while mosaic offtypes produced only 7% (P<0.001). TC plants produced their first crop 60 days earlier than plants from suckers; thereafter bunch to bunch intervals were similar. TC plants also produced 40% more (P<0.001) suckers during the first 18 months in the field. Within the Williams clone, normal TC plants (offtypes excluded) produced 15% more fingers per bunch in the plant crop than plants propagated as suckers (P<0.001). As TC plant crop fingers were 8% smaller (P<0.01), total fruit weight per bunch was 6% greater (P<0.05). Yield parameters were not significantly different during the first ratoon, but in the second ratoon TC plants had 5% more (P<0.05) fingers and 9% greater (P<0.01) total fruit weight. In the clonal comparison Chinese Cavendish was the shortest plant, had below-average finger size, and its production of marketable fruit was below average. Mons Mari-WR was the tallest clone with the longest fruit, and the highest production of marketable fruit. Other clones were intermediate in height and production.
Effects of hydroponic solution composition, electrical conductivity and plant spacing on yield and quality of strawberries
Authors: Sarooshi RA , Cresswell GC
Published: March 2005

The influence of nutrient solution adjustment and replacement (management), its electrical conductivity (EC) and plant spacing on yield and quality of strawbeny fruit (var. Torrey) produced in a recirculating hydroponic system was studied at Gosford, New South Wales. Four ways of managing the nutrient solution were examined: (i) pH and EC adjusted daily and the solution replaced every 8 weeks (current grower practice); (ii) as above except that a topping up solution with lower potassium to nitrogen (K: N) ratio was used for EC adjustment; (iii) no daily adjustment of EC or pH and one-third of solution replaced every 2 weeks; and (iv) no daily adjustment of solution volume, EC or pH and full replacement after 8 weeks. Compared with grower practice, these alternative solution management strategies provided no advantage in yield, fruit number, or in the �Brix, citric acid, sweetness or flavour of fruit. Use of a topping up solution supplemented with ammonium nitrate (NH4NO3) and calcium nitrate [Ca(NO3)2] to reduce the K : N ratio from 1.7:1.0 to 1.4:1.0 had no effect (P>0.05) on yield but significantly increased (P<0.05) berry weight and improved fruit aroma. Regardless of which method of nutrient solution adjustment and replacement was used, the chemical composition of the recirculating solution changed markedly over 53 days. The method of nutrient solution management significantly (P<0.05) affected leaf phosphorus (P), calcium (Ca), magnesium (Mg), manganese (Mn), and zinc (Zn) but only Mg fell to a suboptimal level for growth of strawberries. Reducing the EC of the nutrient solution from 3 to 2 dS/m at early fruit set gave heavier (P<0.05) berries compared with constant EC of 2 dS/m. Increasing the EC from 2 to 3 or reducing it from 3 to 2 at early fruit set resulted in sweeter (P<0.05) berries and reducing the EC from 4 to 2 improved fruit aroma. Yield declined (P<0.05) when EC was increased from 2 to 4 dS/m. Solution EC bad significant effects (P<0.05) on leaf P, Mg, Mn and Zn. An increase in planting density from 5.35 to 9.35 plants/m2 lowered (P<0.05) marketable yield per plant and fruit acidity but gave 41% higher (P<0.05) yield on an area basis.
Effect of inoculating fungi into compost on growth of tomato and compost microflora.
Authors: Sivapalan A , Morgan WC Franz PR
Published: March 2005

The ability of Acremonium butyri, Chaetomium globosum, Gliocladium roseum, Trichoderma Izamatum and Zygorrhynchus moelleri to enhance growth of tomato plants cv. Alta was examined by inoculating soilless compost with these fungi. The effect of inocula on the population of other microflora in the compost was also examined. T. hamatum and Z. moelleri significantly (P<0.05) increased the growth of tomato plants and this increase was greater than resulted from normal fertiliser practice adopted by growers. The population of inoculated T. hamatum and Z. moelleri remained constant in compost with or without tomato plants whereas the populations of other introduced fungi declined with time. Each of the 5 introduced fungi reduced the original populations of Fusarium, Penicilliunz and Mucor, but not the total bacterial or actinomycete populations. The microbial populations were significantly (P<0.05) higher in compost with plants than in compost without plants.
Constraints to the adoption of innovations in agricultural research and environmental management: a review
Authors: Guerin LJ , Guerin TF
Published: March 2005

There are several constraints to the adoption of technologies and innovations by Australian farmers. Here an attempt has been made to define the major constraints to adoption. These are identified as: the extent to which the farmer finds the new technology complex and difficult to comprehend; how readily observable the outcomes of an adoption are; its financial cost; the farmer's beliefs and opinions towards the technology; the farmer's level of motivation; the farmer's perception of the relevance of the new technology; and the farmer's attitudes towards risk and change. The classical adoption-diffusion model and subsequent modifications are discussed. In particular, issues relating to the participatory action research (PAR) approach are raised and discussed. In addition, methodologies in extension research are briefly discussed and the roles of extension personnel and agricultural scientists in the technology adoption process are examined. The adoption of innovations in natural resource management is discussed and the findings indicate that this is an area of agriculture in which extension practice and research will play an increasingly important role in the future. Recommendations for further research into adoption of technological innovations in resource management and agriculture are made.
Feeds and feeding methods for assembly of sheep before export
Authors: McDonald CL , Rowe JB , Gittins SP
Published: March 2005

Sheep are assembled in Australian feedlots before export and given time to adapt to the pelleted diet they will receive on board ship. In Western Australia, lupins are normally included in the diet at levels up to 30% as a source of digestible energy which is low in starch. It is also common to feed hay during assembly. We examine the use of pellets based on barley and containing either lupins or virginiamycin to overcome problems of acidosis, and the importance of hay during assembly. There were 9 dietary treatments each with 3 pens of 30 sheep. The study was conducted over 8 days simulating assembly feedlot conditions. Measurements were made of numbers of sheep visiting troughs (paint-marking technique) and accumulation of lactic acid in the rumen. 'Barley' pellets were formulated with 33% barley, 18% oats, 47% hay/straw and 2% minerals and vitamins. Replacing about half of the barley with lupins resulted in more sheep paint-marked on days 3-6 (P<0.05) and higher levels of feed intake on days 4-8 (P<0.001) than feeding pellets without lupins. The inclusion of lupins was also associated with a less pronounced drop in feed intake on day 4 than measured in sheep fed barley pellets alone. Adding virginiamycin at 40 g/t to the basal barley-based pellet also significantly increased the numbers of sheep paintmarked. Virginiamycin appeared to have a similar effect to the inclusion of lupins in terms of reducing the number of sheep which were not paint-marked. Sprinkling a small quantity of lucerne chaff onto the pellets had no effect on feeding behaviour. The use of hay in racks resulted in fewer sheep (3 v. 12%, P<0.05) not eating during the first 3 days but there was no significant effect thereafter. We concluded that the inclusion of either lupins or virginiamycin is effective in improving the adaptation to cereal-based pellets in export feedlots. The use of hay either in racks or sprinkled over the pellets appears to be of limited value.
Yield, nutritive value, and phenotypic variability of tall wheatgrass grown in a nonsaline environment
Authors: Smith KF , Lee CK , Borg PT , Flinn PC
Published: March 2005

The phenotypic variation of 10 important botanical traits and 2 traits related to herbage quality was measured in tall wheatgrass (Thinopyrum elongatum) cv. Tyrrell. Five certified lines of Tyrrell were compared among themselves and with cvv. Largo and San Jose. Significant differences, both between cultivars and within lines of Tyrrell, were observed for several traits. The phenotypic variability measured confirms that Tyrrell is distinct from its progenitor, Largo, and has sufficient variability to make it suitable for use in a selection program. In a second experiment, from November 1990 to February 1993, the yield and nutritive value of Tyrrell, Largo, and San Jose were compared with perennial ryegrass (Lolium perenne) cv. Ellett and tall fescue (Festuca arundinacea) cv. Demeter. There were no differences (P>0.05) between cultivars for either total dry matter yield or total yield of digestible dry matter. Seasonal differences in growth and nutritive value were observed. Ellett showed superior growth in winter and early spring, while tall wheatgrass and Demeter were more summer-active. In 6 of the 11 harvests measured for nutritive value, there were no differences (P>0.05) between treatments for yield of digestible dry matter; for 2 of the remaining 5 harvests, Tyrrell yielded more digestible dry matter than Ellett. Dry matter digestibility of tall wheatgrass did not fall below 60%. The results suggest that with appropriate management, tall wheatgrass can produce nutritious forage in quantities sufficient for animal production systems, particularly as a special purpose summer pasture.
The developing relationship between Stylosanthes and anthracnose after 14 years in a North Queensland pasture. 2. Diversity in the pathogen population
Authors: Davis RD , Boland RM , Howitt CJ
Published: March 2005

Broad diversity was indicated in fungal isolates of Colletotrichum gloeosporioides collected from a mixed accession Stylosanthes pasture during 1987-89. Isolate pathogenicity studies revealed 7 different pathogenic groups in 1987, while 16 different groups were separated in the 1989 collection. About 40% of isolates from both years were capable of producing symptoms on only 2 differential host lines while the more complex groups (pathogenic on 3-6 differentials) were proportionately less common. Fungal growth at 4 temperatures revealed significant variation in growth rates although most isolates grew optimally at 28�C. When 3 isolates representing different pathogenic groups were examined in a series of glasshouse inoculum composition studies, all contributed evenly to the number of lesions produced when inoculated together in equal proportions. There was no evidence of domination by the most virulent isolate used in these glasshouse studies and similarly there was no evidence of particular strain dominance in the field. Continual natural diluting of virulent field inoculum by the large diversity of other strains would probably prevent rapid severe epidemics developing in this pasture.
Relationship between herbicide resistance in Lolium rigidum and populations of Anguina funesta, the nematode vector in annual ryegrass toxicity
Authors: Riley IT , Gill GS
Published: March 2005

Samples of annual ryegrass (Lolium rigidum Gaudin) seed tested for herbicide resistance were examined for seed-galls of Anguina funesta, the nematode vector of Clavihacter toxicus the causal bacterium in annual ryegrass toxicity (ARGT). Of the 246 samples examined, 63% contained galls, with concentrations up to 1400 galls per 10 g of seed. Higher herbicide resistance was associated with increased concentrations of A. funesta. We conclude that use of selective herbicides for ARGT control may have contributed to the rapid development of herbicide resistance.
A comparison of air-shear and electrostatic spray technology with a conventional air-blast sprayer to thin apples
Authors: Oakford MJ , Jones KM , Bound SA , O'Rielly L
Published: March 2005

Red Delicious apple trees at Spreyton in northwest Tasmania were thinned with ethephon using an air-shear-electrostatic sprayer (low volume: 100 or 200 L/ha with or without electrostatics) or a commercial air-blast sprayer (high volume: 2000 or 4000 L/ha). Treatments were applied at 2 and 10 days after full bloom. Also included were an unsprayed control and a hand-thinned treatment (15-20 days after full bloom). Carbaryl + Thiram was also applied 3 times (20, 32 and 40 days after full bloom) using the same spray treatments. All dosage rates were equilibrated to apply the same amount of active ingredient/ha. The spray treatments thinned fruit more than the controls when compared for fruit number and all size variables measured except percentage of fruit >80 mm. There were significant differences for fruit number between the hand-thinned, 4000 L/ha high volume and 200 L/ha air-shear treatments, and all the remaining treatments. This applied to both total numbers of fruit set or numbers of fruit hand-thinned at 80-90 days after full bloom. This late hand-thinning had the effect of evening up the fruit size but the control still had significantly smaller fruit than all the other treatments due to the larger number of fruit carried through to hand-thinning.
Minilee and Mickylee are mini-watermelons with potential for the Australian market
Authors: Barnes JA , Zischke BH , Blight GW , Chapman JC
Published: March 2005

The watermelon industry aims to produce fruit 2 10 kg, but supermarkets sell cut portions, so there may be a market for smaller fruit, between 2 and 4 kg. We tested several small-fruited watermelon cultivars to see if there was potential to establish a mini-watermelon industry. Minilee and Mickylee (ex Florida) were the best 2 cultivars; the fruit of 3 Taiwanese cultivars split under slight pressure, and the fruit of the cultivars Sugar Baby and Baby Fun were too heavy. Minilee and Mickylee were grown at plant densities between 5550 and 22 200 plants/ha. At 7400, 11 100 and 14 800 plants/ha, 70-72% of the Minilee fruit weighed between 2 and 4 kg. In contrast, at 22 200 plants/ha, 79% of the Mickylee fruit weighed between 2 and 4 kg, but at the other plant densities only 38-59% of the fruit were in this weight range. We conclude that Minilee and Mickylee are suitable cultivars for a mini-watermelon industry around Bundaberg and probably other parts of Australia where Florida cultivars are presently grown. Because the yield of fruit in the 2-4 kg range for Minilee was less sensitive to plant density than the Mickylee yield in this range, we believe that Minilee would be the better commercial proposition.
Effect of nitrogen, potassium and phosphorus on the yield, growth and nutrient status of ixodia daisy (Ixodia achillaeioides ssp. alata)
Authors: Maier NA , Barth G , Bennell M
Published: March 2005

The effect of annual applications of nitrogen (N), potassium (K) and phosphorus (P) on the yield, growth and nutrient status of Ixodia daisy (Ixodia achillaeioides ssp. alata) grown on a silty loam, was investigated in field experiments conducted during 1989-91 in the Mount Lofty Ranges, South Australia. The experimental design was a randomised block with 3 replications. The N and K treatments, at annual rates up to 200 kg N/ha and 150 kg K/ha, were applied as 2 equal side-dressings. The P treatments, at rates up to 200 kg/ha, were broadcast as 1 annual application. To assess plant nutrient status we sampled the fifth leaf below the growing terminal of 50 stems in October and whole stems at harvest. As rate of applied N increased, there was a significant (P<0.05) increase in total biomass harvested, number of 3040 and 41-50 cm stems, total number of marketable stems, plant height and width. Annual N application rates of 75-110 kg/ha were required for 95% of maximum biomass yield and number of marketable stems. The application of K did not significantly (P>0.05) affect yield or plant growth. First and second order interactions between N, K and year were not significant. Plant growth and yield responses to P applied as superphosphate were inconsistent and the interaction between P and year was not significant (P>0.05). Coefficients of determination (r2) for relationships between N, K and P concentrations in the fifth leaf samples v. total biomass yield and total stem number, were in the range 0.13-0.52 for the combined 1990 and 1991 data. Based on sensitivity, reproducibility and occurrence of the Piper-Steenbjerg effect, we concluded that N, K or P concentrations in the fifth leaf sampled in October, or in whole stems at harvest, were not reliable indicators of the nutrient status of Ixodia daisy. The application of N and P did not affect the concentration of minor or micronutrients in the fifth leaf. In contrast, the application of K increased calcium (Ca), magnesium (Mg) and sulfur (S) concentrations by 14.3, 33.3 and 12.2%, respectively. For a high density planting (13,000 plants) we estimated that for N, P and K, 69.4, 6.2 and 83.2 kg/ha, respectively, are removed in marketable stems. The application of P increased extractable-P concentrations in the surface (0-15 cm) soil from 22 to 73 mg/kg. We suggest that for surface (0-15 cm) soils, extractable-P and extractable-K concentrations in the ranges 15-95 and 210-260 mg/kg, respectively, are adequate and indicate that a yield response to the application of these nutrients in fertiliser may not occur.
Production and quality of Sim carnations grown hydroponically in rockwool substrate with nutrient solutions containing different levels of calcium, potassium and ammonium-nitrogen
Authors: Huett DO
Published: March 2005

The effects of 3 nutrient solution formulations on the production and quality of the Sim carnation varieties, Raggio d'Sole, White Sim, Manon and Doria grown in rockwool substrate were evaluated over 12 months in northern New South Wales. The solutions were: a standard (Std) formulation with a K:N ratio of 1.29:1.00, approximating that in mature carnations with N supplied as NO3-; the standard solution with 10% of the N as NH4+ (Std + NH4+); and a formulation with increased Ca and reduced K (High Ca). Production peaks occurred in March and October when the substrate was sampled for leachate nutrient composition and the flowers were assessed for quality. Total flower production from the Std + NH4+ (9.9/plant) and High Ca (9.7/plant) treatments exceeded (P<0.01) the Std solution (8.4/plant) from February to July while production from all treatments was similar (P>0.05) (mean of 10.3/plant) from August to December. Over February-December, production from the Std + NH4+ treatment (20.8/plant) exceeded (P<0.05) the other formulations. In excess of 75% of these flowers were first grade and the numbers of second and reject grades were not affected (P>0.05) by nutrient solution formulation. Stem diameter, stem strength and vase life were unaffected by nutrient formulation while flowers produced in March had thinner (3.11 v. 5.24 mm diameter) and weaker (139 v. 42 mm deflection from horizontal) stems than those produced in October. The pH in rockwool slabs was stable over time and compared to the standard treatment (7.17), it was lower (P<0.01) for the Std + NH4+ (6.13) and High Ca (6.76) treatments. The High Ca formulation increased Ca and reduced K concentrations in leaves, stems and flowers. Nutrient concentrations in youngest fully expanded leaves for all treatments were within the adequate range. The mean K: N ratio in mature carnations was 1.39:1.00 and this ratio with 10% of the N as NH4+ can be recommended in a nutrient formulation for commercial hydroponic carnation production in Australia.
Assessing Wiltshire Horn-Merino crosses. 1. Wool shedding, blowfly strike and wool production traits
Authors: Rathie KA , Tierney ML , Mulder JC
Published: March 2005

Wiltshire Horn-Merino (WH-M) crosses of 1/2, 5/8 and 3/4 Merino content were compared over 10 years for wool shedding, blowfly strike frequency and wool production traits. Merinos and 1/2 Merino WH-M were compared over 4 years. For wool production traits, 1/2 and 5/8 Merino WH-M ewes were compared to Border Leicester-Merino (BL-M) ewes over 2 years. Shedding increased with age for all WH-M genotypes, with 3/4 Merinos showing less shedding than 1/2 Merinos at all ages. At 1 and 2 years of age, 5/8 Merinos were intermediate between the other 2 WH-M genotypes, but at later ages they were similar to 1/2 Merinos. All genotypes showed less shedding at the belly site than the head, neck and breech as lambs, but not at older ages. Phenotypic correlations between sites on the same sheep were high, averaging 0.85. Repeatability estimates for each site ranged from 0.26 to 0.45. Shedding increased most with age in the 1/2 Merinos, and least in the 3/4 Merinos. Little or no shoulder and back wool was shed by most sheep. All 1/2 and 5/8 Merinos and most 3/4 Merinos had bare legs and points. Blowfly strike incidence was far higher in Merinos than 1/2 Merinos, in all years. Among WH-M, blowfly strike incidence increased as Merino content increased, in all years. All WH-M were far inferior to both Merinos and BL-M in total greasy wool weight and all its components, and also in clean fleece weight, with their level of inferiority increasing as their Merino content declined. Wool fibre diameter for all WH-M was coarser than for Merinos, but was a little finer than for BL-M. Fibre diameter increased in the WH-M as their Merino content declined. All WH-M had lower wool yields than the Merinos or BL-M. In some years the 314 Merinos had lower wool yields than the 1/2 and 5/8 Merinos, which were similar in all years. Shedding caused numerous genotype x age interactions in wool weight and its components, as Merinos and BL-M did not shed, and with the WH-M shedding increased most with age in the 1/2 Merinos, and least in the 3/4 Merinos. Due to preferential shedding from the belly and other low-value areas, the WH-M inferiority in total wool weight was less severe for fleece weight. Winter shearing succeeded in harvesting some wool from WH-M that would be shed before a summer shearing, but not enough to alter rankings among genotypes. All WH-M genotypes have wool too coarse, and not enough of it, to compete as a wool sheep with the Merino at current wool prices under usual Australian pastoral conditions. In areas where mustering is difficult or blowfly strike unusually severe, WH-M genotypes may find a niche.
Location and retention of transponders used for electronic identification of sheep
Authors: Hunt ER
Published: March 2005

Electronic identification implants in sheep were evaluated in relation to advantages offered over traditional tag systems. The 2 (medial and posterior) techniques located transponders under the scutiform cartilage of the ear. In neither technique were all implants retained, or capable of being read, nor could they be adequately recovered during commercial slaughter, thereby limiting the value of the scutiform cartilage as an implantation site.
Differential rhizobial colonisation of the roots of sown and volunteer annual species of Medicago in an acid soil
Authors: Barclay RM , Hebb DM , Brockwell J
Published: March 2005

Two annual medics, Medicago murex and M. truncatula, were inoculated with specific strains of Rhizobium meliloti, WSM540 and CC169, respectively, and sown into a mildly acid red earth in a semi-arid environment at Cobar, New South Wales. A third medic, M. laciniata, volunteered abundantly at the experimental site and large populations of its specific strain(s) of R. meliloti were naturalised in the soil. Serial dilution, plant infection tests, using 3 test plants in parallel, were employed to count the populations of each of the 3 types of R. meliloti that colonised the roots (rhizospheres) of the 3 medics. The size of the rhizosphere populations was regarded as an index of nodulation potential. Large populations of the naturalised rhizobia (about 45000lplant) developed in the rhizospheres of M. laciniata; these rhizobia also colonised the root surfaces of the sown medics but in much lower numbers (< 80/plant). Strain WSM540 colonised the rhizospheres of M. murex in sufficient numbers (1121 rhizobia/plant) to indicate that an effective nitrogen-fixing symbiosis would have established had seasonal conditions permitted. By contrast, the colonisation of M. truncatula rhizospheres by CC169 was significantly lower (64 rhizobia/plant; P<0.05) and the likelihood of nodulation was uncertain. Both WSM540 and M. murex are known to be acid tolerant whereas both CC169 and M. truncatula are acid sensitive. There was very little colonisation of the rhizospheres of the sown medics by non-specific inoculant strains. Nor was there evidence that the large naturalised population of rhizobia for M. laciniata competed with the specific inoculant strains for colonisation of the roots of the sown medics or interfered with their potential nodulation.
Effects of herbicides on wallaby grass (Danthonia spp.) 1. Establishment
Authors: Lodge GM , McMillan MG , Schipp AJ , Cook AS
Published: March 2005

Two experiments were conducted at Tamworth, New South Wales, to assess the effects of herbicides applied post-sowing pre-emergence, and at 2 post-emergence growth stages, on Danthonia (wallaby grass) dry matter yield, plant number, and plant phytotoxicity. Phytotoxicity was scored visually on a 0-5 scale (0, no phytotoxicity; 5, 100% phytotoxicity). In the post-sowing pre-emergence study, no Danthonia plants survived on plots sprayed with metribuzin (375 g a.i./ha), chlorsulfuron (45 g a.i./ha), or simazine (750 and 1500 g a.i./ha). Phytotoxicity was also high at lower rates of metribuzin (187.5 g a.i./ha) and chlorsulfuron (22.5 g a.i./ha). Dry matter yields and plant numbers on 2,4-D amine and ester treatments were not significantly different from those of unsprayed controls. On metsulfuron-methyl (3 and 6 g a.i./ha) and triasulfuron (21.4 g a.i./ha) treatments, plant numbers were similar to the controls, but Danthonia yields were lower (P<0.05). In seedling stands, the only herbicide that reduced (P<0.05) Danthonia dry matter yield compared with the unsprayed control plots was metsulfuron-methyl applied at 6, 12, and 18 g a.i./ha at the 2-4 tiller stage, and at 12 and 18 g a.i./ha at early stem elongation. At both times of application, Danthonia plant numbers were lowest (P<0.05) on the metsulfuron-methyl 12 and 18 g a.i./ha treatments. Phytotoxicity scores were >2 and highest (P<0.05) on all metsulfuron-methyl plots. These studies indicated that a range of chemicals could be used to control broadleaf weed seedlings, without damaging Danthonia seedlings.
Revegetation of a scalded saline discharge zone in central Queensland. 1. Selection of tree species and evaluation of an establishment technique
Authors: Hoy NT , Gale MJ , Walsh KB
Published: March 2005

Species selection trials using 38 tree species were undertaken on salinised, waterlogged land [watertable within about 1 m of soil surface, electrical conductivity (ECw) about 30 dS/m, surface soil (0-0.1 m) EC1.5 about 10 dS/m] in coastal central Queensland. Casuarina glauca and C. obesa gave best survival and growth, while Eucalyptus camaldulensis and C. cunninghamiana gave good initial survival but succumbed to salt and waterlogging stress after several years. The role of soil mounding and mulching for the establishment of C. glauca was investigated in a factorial experiment involving 2 levels of soil mounding (nil, 0.15 m) and 4 mulch conditions (nil, hay, black plastic, white plastic), and in a second experiment involving bagasse, soil amendment with calcium, and the installation of a double ridge in the mound. The low u soil mounding had little effect on plant survival or growth, or soil conductivity; however, mulching greatly influenced these parameters (e.g. about 2 years after a summer planting, tree survival, tree growth, and surface soil conductivity in a plastic mulch treatment was 566, 210, and 60%, respectively, of values of the no-mulch treatment, with a mean tree height of about 3 m in the plastic mulch treatment). Plastic mulch was recommended over hay or bagasse mulch for short-term (<2 years) increase in plant survival and growth (e.g. 15 months after a summer planting, height of plants established in plastic mulch rows was 124% of that in hay-mulched rows). The incorporation of a small trough in the crown of the bed was found to improve plant growth significantly (tree height in troughed mounds 120% of that in untroughed mounds, 15 months after planting), but did not improve establishment. Soil amelioration with lime, gypsum, or dolomite at 3.0 t/ha did not improve plant growth. A further trial at another salinised site confirmed the success of the plastic mulch-crown trough technique, relative to conventional preparation techniques (i.e. ripping).
Response of Australian barley cultivars to leaf rust (Puccinia hordei)
Authors: Cotterill PJ , Rees RG , Platz GJ
Published: March 2005

Thirty-eight Australian commercial cultivars of barley were screened as seedlings against 11 pathotypes of the leaf rust pathogen (Puccinia hordei Otth.) detected in Australia, and as adult plants in the field against the 2 predominant pathotypes (210 P+ and 200 P+) present in the eastern mainland states. Most cultivars were susceptible as seedlings to 10 of the pathotypes of P hordei (with infection types of 3 or 4 on a 0-4 scale) but only 17 were susceptible to pathotype 253 P-. Abyssinian, Franklin, Tallon and Triumph were susceptible to none, Skiff only to 210 P+, Grimmett and Shannon only to 210 P+ and 253 P- and Ulandra to pathotypes 202 P+, 243 P-, 243 P+, 253 and 262 P+. Cutter, Ketch, Prior, Schooner and Weeah were susceptible to all except 200 P-, 201 P-, 243 P-, and 253 P-, and Yerong to all except 200 P-, 201 P-, 202 Pt, 220 P+ and 262 P+. Some cultivars, notably Malebo, but also Corvette, Galleon, Schooner and, to a lesser extent, Yerong were not as susceptible (infection types of 3 to 3+/4-) to most pathotypes of P. hordei. As adult plants in the field, Abyssinian, Franklin, Tallon and Triumph were resistant, and Malebo and Ulandra moderately resistant/moderately susceptible to both pathotypes tested.
Phosphorus nutrition of large-seeded chickpea cv. Macarena (Cicer arietinum) in the Ord River Irrigation Area, Western Australia
Authors: Riley IT
Published: March 2005

The phosphorus (P) nutrition of largeseeded chickpea (Cicer arietinum) cv. Macarena grown on Cununurra clay in the Ord River Irrigation Area was studied in field trials and by sampling commercial crops. Response to applied and residual P on a previously uncropped site (site 1) was examined over 2 growing seasons and to applied P on a site with a history of cropping (site 2) in 1 season. At site 1, yield increased with application of up to 50 kg P/ha in the first year and 100 kg P/ha in the second year. There was no significant response in the second year to the P applied in the previous season, probably because of rapid fixation of P in Cununurra clay. At site 2, with a residual soil P level of 24 �g/g (HCO3), no growth response to applied P was observed. The survey of commercial crops included determination of P in soil, foliage, and seed, and the recording of phosphatic fertilisers applied. The data indicate that excessive P fertiliser is applied to many chickpea crops, with only a few crops being inadequately supplied.
Time of nitrogen application and yield of Bengal lychee on a sandy loam soil in subtropical Queensland
Authors: Menzel CM , Haydon GF , Doogan VJ , Simpson DR
Published: March 2005

Nitrogen (N) was applied over 4 years to 6-year-old lychee trees (Litchi chinensis Sonn. cv. Bengal) growing in subtropical Queensland (lat. 27�S.) on a sandy loam soil (0-15 cm) with 2.8 mg nitrate-N/kg, to determine the effect of time of N application on leaf N concentration, vegetative growth, flowering, and yield. Applications of N (equivalent to 750 kg N/ha in year 4) were made after panicle emergence in July, after harvest in January, or split between the 2 periods. Control trees received no N. Leaf N concentrations in April-June were, on average, about 0.1% lower after a single N application in winter than application in summer or split applications. Leaf N concentrations in November-February were about 0.1% higher after winter or split N applications than after summer applications. Timing of fertiliser application had no affect on yield. It took 4 years without N fertiliser to show significant reductions in yield compared with fertilised trees. In year 4, yield increased from 20 to 60 kg/tree on individual pairs of trees as leaf N in August increased from 0.95 to 1.56%. Lower yields in control trees in year 4 were associated with poor leaf growth in the previous 2 years, and with lower concentrations of N in the panicles, leaves, twigs, and small branches, as well as lower chlorophyll concentrations and net CO2 assimilation after fruit set, compared with trees receiving N.
Effects of nitrogen, phosphorus, and potassium on yield, specific gravity, crisp colour, and tuber chemical composition of potato (Solanum tuberosum L.) cv. Kennebec
Authors: Maier NA , Dahlenburg AP , Williams CMJ
Published: March 2005

Five field experiments were conducted over 3 years in the Mt Lofty Ranges (4 sites) and the Upper South East (1 site) to examine the significance of main effects and interactions between nitrogen (N, up to 360 kg N/ha), phosphorus (P, up to 320 kg P/ha), and potassium (K, up to 480 kg K/ha) on total yield, yield of 80-350 g size grade, specific gravity, crisp colour, and chemical composition of tubers of potato cv. Kennebec. There were significant (P<0.05) main effects of increasing rates of applied N on total tuber yield and yield of 80-350 g tubers at 2 of the 5 experimental sites; the effect of applied P was significant at 3 sites, and applied K also at 3 sites. Application of N, P, and K increased total tuber yield by 13-432%, 19-145%, and 19-89%, respectively, at responsive sites. Increases in the yield of 80-350 g tubers were similar to those for total yield. There were significant first-order interactions (N x K, N x P, K x P) at 2 sites. The interactions were (i) response to the application of 1 nutrient limited by suboptimal rates of another; and (ii) yield depression, due to high rates of 1 or more nutrients. Nitrogen and P increased specific gravity at only 1 of the sites where they were applied. Potassium increased specific gravity at 1 site but decreased it at another. There were significant N x K, N x P, and K x P interactions at 2 sites. Vascular ring colour index (CI) and medulla CI were significantly (P<0.05) affected by rates of applied N, P, and K at 1, 3, and 4 experimental sites, respectively. Application of K (up to 480 kg K/ha) decreased vascular ring CI and medulla CI. Application of P increased the colour indices; for example, increasing the rate of P from nil to 160 kg/ha increased mean (� s.e.) vascular ring CI from 51 � 18 to 117 � 17. No interactions between N, P, and K in their effects on medulla CI were significant. For vascular ring CI, significant first-order interactions (K x N, K x P) were observed at 2 sites, at which application of N and P at nil K significantly increased vascular ring CI. At 240 or 480 kg K/ha, there was no change. Significant (P<0.001) curvilinear relationships were found between specific gravity and the concentrations of N, P, and K in the stem-end region of tubers; the coefficients of determination (r2) were 0.27, 0.62, and 0.76, respectively. For the combined medulla CI and vascular ring CI data, the corresponding values were 0.19 (P<0.001), 0.29 (P<0.001), and 0.05 (n.s.), respectively.
Petiole sap nitrate is better than total nitrogen in dried leaf for indicating nitrogen status and yield responsiveness of capsicum in subtropical Australia
Authors: Olsen JK , Lyons DJ
Published: March 2005

This study was conducted to assess the usefulness of petiole sap nitrate and total nitrogen (N) in dried leaf for determining N status and yield response in capsicum (Capsicum annuum L.) grown with plastic mulch and trickle irrigation in subtropical Australia. Five rates of N (0, 70, 140,210, 280 kg/ha) were applied in factorial combination with 2 rates of potassium (K: 0, 200 kg/ha) in randomised block experiments to capsicum cv. Bell Tower grown at Bundaberg Research Station in spring 1990 and autumn 1991. Critical nutrient ranges for nitrate concentration in petiole sap and for total N concentration in dried youngest mature leaf blades plus petioles (YMB + P) were derived at different stages of crop development (bud development, BD; first anthesis, FA; 80% flowering, F; fruit set, FS). Sap nitrate was about 5 times more sensitive to changes in N application than total N. Petiole sap nitrate accounted for a greater amount of the variation in marketable fruit yield (quadratic square root relationships, 0.45 < R2 < 0.83) than total N concentration in dried YMB + P (linear relationships, 0.29 < R2 < 0.74). Simple linear regressions indicated a stronger relationship between applied N and petiole sap nitrate concentration than total N concentration in dried YMB + P (range in R2 values among 8 sampling events: 0.71-0.91 for petiole sap nitrate, 0.35-0.78 for YMB + P total N). For the fertiliser application strategy, 60% of N was applied pre-fruitset and 40% after. Sap nitrate concentrations associated with 95 and 100% of maximum marketable fruit yield increased from BD (5010-6000 mg/L spring, 4980-5280 mg/L autumn) to FA (6220-7065 mg/L spring, 555M000 mg/L autumn). After FA, the range progressively decreased to 1640-2800 and 520-1220 mg/L at FS, for spring and autumn, respectively. It was concluded that petiole sap nitrate was a better indicator of plant N status and yield response than total N concentration in dried YMB + P for capsicum in subtropical Australia. A critical petiole sap K concentration (corresponding with maximum yield and at which no yield response to K addition was measured) of >4800 mg/L was proposed by correlating sap K with yield responses.
Effects of irrigation and nitrogen on the yield components of fennel (Foeniculum vulgare Mill.)
Authors: Buntain M , Chung B
Published: March 2005

A field experiment was conducted to study the effects of irrigation and nitrogen applied at different growth stages on the oil and anethole yields of fennel (Foeniculum vulgare Mill.), and its yield components. Irrigation increased the yield of whole plant dry matter, with the stem elongation stage being the most sensitive. Full irrigation and irrigation applied during the flowering and late flowering growth stages increased umbel and oil yields. Irrigation during the late flowering stage made the greatest contribution to oil yield, accounting for >80% of the yield due to full irrigation. This was attributed to the concurrent timing of irrigation during the late flowering stage with dry conditions and the development of the main oil-bearing structures, the secondary and tertiary umbels. Irrigation had no significant effect on the anethole concentration of the oil. The best economic return was achieved by irrigating during the late flowering stage. There was no significant effect of nitrogen on any of the yield components measured in this study.
Simulation of the effect of chilling injury and nitrogen supply on floret fertility and yield in rice
Authors: Godwin DC , Meyer WS , Singh U
Published: March 2005

Evidence exists that night temperatures <18�C immediately preceding flowering in rice crops can adversely affect floret fertility and, hence, yields. It has been suggested that sterility induced by low temperature is also influenced by floodwater depth and nitrogen (N) rate. In southern New South Wales, low night-time temperatures are believed to be a major constraint to the achievement of consistently high yields. The availability of a comprehensive model of rice growth and yield that is sensitive to this constraint would aid the development of better management practices. CERES RICE is a comprehensive model that simulates the phasic development of a rice crop, the growth of its leaves, stems, roots, and panicles, and their response to weather. It also simulates the water and N balances of the crop and the effects of stresses of water and N on the yield-forming processes. The model has been extensively tested in many rice-growing systems in both tropical and temperate environments. However, the original model was unable to simulate the level of chilling injury evident from yield data from southern New South Wales. This paper reports modifications made in the model to simulate these effects and the evaluation of the model in environments of low night temperature. Inclusion of the chilling injury effect greatly improved the accuracy of estimated yields from treatments in an extensive field experiment. However, additional testing with a wider range of data sets is needed to confirm the international applicability of the modifications.