Completed projects and reports

Permanent URI for this communityhttp://elibrary2.sugarresearch.com.au/handle/11079/13840

Sugar Research Australia, Sugar Research Development Corporation and BSES reports from completed research projects and papers.

Browse

Filters

2020 - 20213

Advanced Search

Filter by

Settings

Author: search.filters.author.Fillols, EStart date: 2020

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Effect of the soil-binding adjuvant Grounded® on herbicide efficacy and runoff losses in bare soil in ratoons : ASSCT peer-reviewed paper
    (ASSCT, 2021) Fillols, E; Davis, A
    To reduce the impact of pesticides, in particular pre-emergent herbicides, on fresh and estuarine water bodies of the Great Barrier Reef catchment, while maintaining productivity, the sugar industry is exploring innovative options to reduce the movement of herbicides off site. Previous research work has shown the oil-based adjuvant Grounded® added at 3 L/ha to the herbicide tank reduced runoff losses by 17 to 40% across all tested herbicides at 48 h and 3 weeks after product application, when applied on bare soil in a tilled plant cane in far northern Queensland. Herbicide efficacy was maintained above 90% for 200 days after product application with or without the addition of the adjuvant. Conversely, Grounded® did not reduce runoff loss when added to herbicides applied in trash blanketed ratoon. This paper presents additional research work carried out to assess the impact of Grounded® on pre-emergent herbicide efficacy and on runoff losses when applied to ratoon cane on bare soil. This scenario is typical of the Burdekin and New South Wales regions. Two trials were conducted in untilled ratoons after burning the trash blanket in far northern Queensland. Grounded® was added to six registered pre-emergent herbicides: imazapic (94.5 g/ha), hexazinone (472.5 g/ha), isoxaflutole (150 g/ha), amicarbazone (700 g/ha), atrazine (1350 g/ha) and pendimethalin (1001 g/ha). Herbicide efficacy trials were implemented as randomised complete blocks with three replicates and adjacent untreated controls. Losses of the tested pre-emergent herbicides in runoff were monitored using replicated rainfall simulations, delivering 80 mm of simulated rain, 48 h or 3 weeks after herbicide application. Both runoff trials generated similar herbicide concentrations in runoff. As expected, higher concentrations for all herbicides were found in runoff 48 h after spraying compared to 3 weeks after spraying. The adjuvant Grounded® added to the spray tank did not decrease herbicide loss via runoff in both trials. Topsoil samples taken before and after rainfall, generally showed higher percentage herbicide in topsoil after rainfall when Grounded® was added to the tank mix compared to no added adjuvant. However, this slight binding improvement to the soil did not result in lower herbicide loss in runoff. These runoff and soil results mirrored previous research results when Grounded® was applied on trash blanketed ratoons. In both efficacy trials, weed control varied at each site between herbicide treatments depending on the environmental conditions and the weed species. However, the addition of Grounded® to each herbicide treatment did not affect the efficacy of any herbicide treatment in both trials. These results show that the oil-based adjuvant Grounded® is unlikely to improve the quality of runoff water leaving sugarcane paddocks when applied to untilled ratoon cane on bare soil.
  • Thumbnail Image
    Item
    Impact of application depth and slot closure on runoff losses of imidacloprid
    (ASSCT, 2020) Fillols, E; Davis, AM
    Imidacloprid represents the Australian sugar industry’s best canegrub-management tool, but it has been detected in many water bodies, including groundwater, creeks, rivers and marine environments, posing a potential risk to the health of the Great Barrier Reef. In ratoon cane, it is commonly applied in liquid form with coulters within the cane row. Imidacloprid product labels state that, when applied in ratoons, the product must be placed at 100–125 mm depth and the slot must be covered; however, it is not uncommon to observe application equipment that does not maintain the desired depth or fails to close the slot appropriately. To investigate the best application methods to reduce imidacloprid runoff, two rainfall-simulation trials were established in the Burdekin and in the Wet Tropics to assess the impact of depth and slot coverage on imidacloprid runoff when the liquid formulation is applied with a stool-splitter tine implement. An additional runoff trial under overhead irrigation was set up in the Wet Tropics to test the efficacy of the StoolZippa™ to close the slot and reduce imidacloprid runoff losses when the product is applied at the correct depth of 100 mm. Results from the rainfall-simulation trials showed higher imidacloprid concentration in runoff from a shallow application at 50 mm compared to the recommended minimum 100 mm application depth. A press wheel reduced the imidacloprid concentration to nil when the product was applied at the correct depth of 100 mm; however, it slightly increased the concentration in the case of the shallow application. In the overhead-irrigation trial, the StoolZippa™ increased the imidacloprid concentrations in runoff versus the slot left open, but these concentrations were still extremely low and not of environmental concern. These trials indicate that ensuring the product is consistently applied at 100 mm depth is the best way to reduce imidacloprid loss via runoff when the product is applied with a stool-splitter tine implement. As trials were only conducted in loam soils at two locations, further trials are recommended over a range of soil types and geographic locations.
  • Thumbnail Image
    Item
    Combining weed efficacy, economics and environmental considerations for improved herbicide management in the Great Barrier Reef catchment area
    (Science of the Total Environment, 2020) Fillols, E; Davis, AM; Lewis, SE; Ward, A
    The current Australian sugarcane industry transition toward adoption of an ‘alternative’ herbicide strategy as part of improved environmental stewardship is increasingly complicated by recent farming system, regulatory and herbicidal product changes. This study quantified and compared the efficacy, economic costs and environmental risk profiles of a range of established, emerging, and recently registered pre-emergent herbicides across field trials in the Wet Tropics region of North Queensland. Several herbicides were effective on certain weed species, but lacked broad spectrum control. Better efficacy results from products with multiple active ingredients (i.e., imazapichexazinone) demonstrated the benefits of using mixtures of active ingredients to widen the spectrum of weed control efficacy. All tested pre-emergent herbicides behaved quite similarly in terms of their propensity for off-site movement in water (surface runoff losses generally N10% of active applied), with their losses largely driven by their application rate. Herbicides with lower application rates consistently contributed less to the total herbicide loads measured in surface runoff. Results demonstrated alternative choices from the more environmentally problematic herbicides (such as diuron) are available with effective alternative formulations providing between 4 and 29 times less risk than the traditional diuron-hexazinone ‘full rate’. However, considerable challenges still face canegrowers in making cost-effective decisions on sustainable herbicide selection. Additional research and effective grower extension are required to address information gaps in issues such as specific weed control efficacy of alternative herbicides and potential blending of some herbicides for more effective broad spectrum weed control, while also minimising environmental risks.