• Authors:
    • Mitchell, C.
    • Dalal, R. C.
    • Wang, W. J.
  • Source: 3rd International Nitrogen Conference
  • Year: 2005
  • Authors:
    • Chan, K. Y.
    • Heenan, D. P.
  • Source: Soil Use and Management
  • Volume: 21
  • Issue: 4
  • Year: 2005
  • Authors:
    • Schilizzi, S.
    • Flugge, F.
  • Source: Ecological Economics
  • Volume: 55
  • Issue: 4
  • Year: 2005
  • Authors:
    • Salmond, G.
    • Swan, L.
  • Source: Australian Cottongrower
  • Volume: 26
  • Issue: 3
  • Year: 2005
  • Summary: In a field in Australia, the influence of growing different rotation crops on the level of Fusarium oxysporum f.sp. vasinfectum (Fov) in the soil was monitored over three years in a summer field crop rotation experiment. In the 2001-02 and 2002-03 seasons of the trial, the same crop was grown on the same plot. The maize plots were a forced fallow during 2002-03. In 2003-04, the entire trial was oversown with cotton cv. Nu Emerald RR. Mung bean plots were replanted with Sicot 14B six weeks later. In glasshouse pot trials, soil naturally infested with Fov was used to examine different rotation options over five crop cycles with cotton oversown across all treatments in the final cycle. In the field, significantly more cotton plants survived until maturity following a bare fallow rotation compared to cotton plants grown following either maize, cotton or sorghum crops. The greatest percentage of cotton plant death and severity of disease in cotton occurred where soyabean or mung bean crops had previously been grown. In the glasshouse, rotation cycles that included a fallow treatment either one or two crops before growing cotton generally resulted in less severe Fusarium wilt (lower MDI) compared to cycles where a fallow treatment was not included occurred early in the cycle. Crops with larger root systems (sunflower, broccoli, lucerne, maize, sorghum) had more disease (higher MDI) in the following cotton compared to crops with smaller root systems (fallow, chickpea, field pea, millet, pigeon pea), after these crops had been grown for four continuous cycles, reflecting the role of residue and organic matter in pathogen survival and disease incidence. Fov has been isolated from mature plants growing in these pot trials including sunflower (5%); maize (4%); sorghum (3%) (roots only); mung bean (24%); field pea (20%); vetch (20%); pigeon pea (12%); chickpea (4%); and lucerne (4%) (stems and roots). Further research into rotation options and the roles of crop residue, organic matter and green manuring of crops in relation to pathogen survival are discussed.
  • Authors:
    • Freudenberger, D.
    • Eldridge, D. J.
  • Source: Austral Ecology
  • Volume: 30
  • Issue: 3
  • Year: 2005
  • Summary: Since European settlement, Eucalyptus box woodlands have been substantially modified by agricultural practices, and in many areas in southern Australia are now restricted to scattered or clumped trees. We report here on a study to examine the impact of trees on water flow (infiltration) in an agricultural landscape with substantial areas of extant native vegetation. We examined infiltration through coarse- and fine-textured soils within four landscape strata, the zones below Eucalyptus melliodora and Callitris glaucophylla canopies, the intertree zone dominated by perennial grasses and a landscape homogenized by cultivation and dominated by annual crops. We measured sorptivity, the early phase of water flow, and steady-state infiltration with disc permeameters at two supply potentials. These different potentials enabled us to separate infiltration into (i) flow through large (biopores) and small pores and (ii) flow through small pores only where biopores are prevented from conducting water. On the fine-textured soils, both sorptivity and steady-state infiltration were significantly greater (approximately fivefold) under the timbered strata compared with the grassy slopes or cultivation. Differences were attributable to the greater proportion of macropores below the tree canopies compared with the nontimbered strata. The lack of a significant difference on the coarse-textured soils, despite their macropore status, was attributed to differences in surface litter and plant cover, which would maintain continuous macropores at the surface and thus conduct large amounts of water. The tendency of slopes covered by cryptogamic crusts and grasses to shed run-off and for the trees to absorb substantial quantities of water reinforced the important ecological service provided by trees, which moderates large run-off events and captures small amounts of water leaking from the grassy patches. In the absence of these 'ecosystem wicks', run-off would find its way into regional groundwater and contribute to rising salinity.
  • Authors:
    • McRae, F. J.
    • Brooke, G.
    • Francis, R. J.
    • Dellow, J. J.
  • Source: Weed control in winter crops 2005
  • Year: 2005
  • Summary: This publication provides a guide to chemical weed control during different growth stages of fallow, wheat, barley, oats, rye, triticale, rape, safflower, lentil, linseed, lupin, chickpea, faba bean and field pea in New South Wales, Australia. Recommended timing of herbicide application is given. Sensitivity of winter crop cultivars to herbicides is outlined. Information is also included on crop rotation, use of surfactants and oils, water quality for herbicide application, spray equipment clean-up, herbicide spray drift, compatibility of winter crop herbicides and insecticides, and common retail prices of chemicals used on winter crops.
  • Authors:
    • Australia, Wagga Wagga Agricultural Institute
  • Source: Cultivar X herbicide screening: 2005 results
  • Year: 2005
  • Summary: The results are included on this CD-ROM for herbicide trials involving wheat, barley, oats, triticale, rape, lupin and field pea. Field trials were sprayed with the recommended application rate (1xR) and twice the rate (2xR). The high rate establishes the safety margin of the herbicide and confirms the differences in tolerances between the cultivars used. New varieties and advanced lines from various breeding programmes were tested at the x2 rate of only a subset of herbicides. Grain yield of sprayed versus unsprayed plots is used as a measure of crop tolerance of the herbicide. The results of not just 2005 trials are included but also those from 2002, 2003 and 2004 are also included on the CD-ROM together with photographs from the trials.
  • Authors:
    • Rogers, G. S.
    • Little, S. A.
    • Silcock, S. J.
    • Williams, L. F.
  • Source: Acta Horticulturae
  • Issue: 638
  • Year: 2004
  • Summary: A no-till system using permanent beds, permanent subsurface irrigation and organic mulches grown in situ was implemented as an alternative to conventional production in an experiment conducted in North Queensland, Australia. The system used a tropical legume, Centrosema pubescens 'Cavalcade', or the C 4 grasses Bothriochloa pertusa 'Keppel' or 'Hatch' as cover crops over summer and autumn. Cover crops were killed using glyphosate (1440 g a.i./ha) and residues were left on the soil surface. Vegetable seedlings were then planted through the mulch residues and grown using conventional agronomic techniques. Following harvest, crop residues were macerated and the following cover crop direct sown through the mulch residues. Soil from conventional production areas using polyethylene mulch had significantly lower aggregate stability than all other treatments. Soil aggregates taken from beneath cover crop mulches were more stable than aggregates under polyethylene mulch after one year under the no-till regime. Soil aggregates after three years of treatment showed similar statistical differences between the treatments. Bulk density in permanent beds under C. pubescens mulch was significantly lower than uncultivated bare soil and frequently cultivated polyethylene mulch. Soil under frequent cultivation was significantly more compacted than uncultivated bare soil. There were significantly more earthworms under C. pubescens and B. pertusa mulch than in uncultivated bare topsoil or under polyethylene mulch. No earthworms were found in any sample under polyethylene mulch. The yields of tomatoes after 5 harvests were not significantly different for conventional and no-till production.
  • Authors:
    • Chen, D.
    • White, R. E.
    • Chapman, D. F.
    • Eckard, R. J.
  • Source: Australian Journal of Dairy Technology
  • Volume: 59
  • Issue: 2
  • Year: 2004
  • Authors:
    • Kelly, K.
    • Edis, R. B.
    • Li, Y.
    • Chen, D.
    • Turner, D.
  • Source: SuperSoil: 3rd Australian New Zealand Soils Conference
  • Year: 2004