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Microplastic extraction from digestive tracts of large decapods
No full textThe reliable quantification of microplastic contamination in chitinous organisms requires validated methods to remove interfering complex organic and inorganic material. This study trialled KOH, H2O2 and HNO3 digestion methods on the digestive tracts of two large decapods (Panulirus cygnus and Portunus armatus) to validate a protocol that facilitates reliable microplastic extraction. KOH digestion provided the best recovery (\u3e95 %) of all polymers (e.g. polyamide, polyethylene, polyethylene terephthalate, polypropylene, polystyrene and polyvinyl chloride), with the lowest impact to their physical morphology and chemical spectra. While HNO3, and HNO3 + H2O2 treatments were more effective at digesting chitin, they destroyed polyamide, and altered several other polymers. High digestion efficiency did not result in high matrix clarification or high microplastic recovery for large decapods. This study emphasises the importance of validating species-specific microplastic extraction methods, whilst proposing additional post-digestion protocols, such as density separation, for complex samples, that can be applied in future research investigating plastic contamination in large decapods
Revealing the impact of spatial bias in survey design for habitat mapping: A tale of two sampling designs
No full textSubmerged aquatic vegetation, referring to benthic macroalgae and plants that obligately grow underwater, are critical components of marine ecosystems and are frequently found to provide preferential recruitment habitats. The mapping and monitoring of aquatic vegetation through remote sensing and machine learning is becoming an important aspect of managing coastal environments at scale. Accurate mapping and monitoring require robust sampling and occurrence data to assess predictive error and quantify submerged vegetation extents. The form of ground truthing survey design (preferential, random, grid-based or spatially balanced) could significantly influence predictive model outcomes and the overall accuracy of mapping and monitoring. Here, we test and contrast mapping aquatic vegetation extent ground-truthed using two different sampling designs: we used both preferential and spatially balanced sampling designs across four coastal sites along the midwest of Australia. We validate the map outcomes using spatial cross-validation and demonstrate that spatially balanced ground truthing significantly outperforms preferential sampling designs regarding modelled extent and map accuracy. In our comparison, we found that, on average, preferential designs overestimated vegetation extent by 25 percent compared to balanced designs and achieved an average kappa statistic, F1 score and Area under the Curve of 0.48, 0.615 and 0.517, respectively; whereas balanced designs achieved a kappa statistic, F1 score and AUC of 0.84, 0.85 and 0.83 respectively. We strongly recommend that sampling designs for remote sensing-derived habitat models be spatially balanced where habitat extent is proposed as a metric for monitoring
To rip on or off the old rip line: a paddock-scale study on deep ripping and topsoil inclusion in a dry season
No full textDeep ripping sands with topsoil inclusion to 45cm increased canola yield on the rip line compared to off the rip line by 24–66% in a decile 1 rainfall season (123mm growing season rainfall achieving 100% of estimated yield potential). Four years after ripping, the topsoil inclusion had created a pathway of better soil pH and lower bulk density for more roots down the rip line through the compacted, acidic and aluminium-toxic subsoil — increasing organic carbon levels to 40cm depth and root access to deeper moisture and nutrients. Plant and soil measurements suggest that subsequent deep ripping with topsoil inclusion in the ‘off row’ to alleviate compaction, could improve pH and nutrition/organic matter. Creating an inclusion zone every 30cm would give each crop row close proximity to a rip line of better fertility and access to moisture each season further increasing yield and the longevity of the ripping benefit
Barley grass and its management in crops
No full textBarley grass is a common name for Hordeum glaucum and H. leporinum. Barley grass is a major crop weeds species because the seed is readily dispersed, it is renowned for rapidly germinating in autumn, and post-emergent herbicide control options are limited. It can also act as an alternate host for cereal diseases and can develop resistance to herbicides.
The rapid germination of the species after rainfall gives barley grass the potential to act as a green bridge for cereal root rot disease
Insect pests and their management in oats
No full textField pests
Damage from invertebrate pests is generally not a major factor for oat crops, however there is a zero tolerance to live pests in export hay.
Significant damage can occur if pest populations build up. Planning rotations to minimise pest carryover, timely sowing, adequate crop nutrition, and good control of weed and root diseases will assist in reducing the likelihood of crop damage by insect pests. Check crops regularly throughout their growth for field insects.
• Control redlegged earth mite and lucerne flea during the seedling stage if necessary.
• Aphids should be checked for and controlled from flag leaf stage and later in crops considered to be high yielding.
• Aphids can also transmit barley yellow dwarf virus (BYDV). If growing susceptible varieties in areas with moderate to high BYDV risk, consider using insecticide seed treatments.
• Unnecessary spray applications have been linked to resistance developing in non-target pests, such as redlegged earth mite.
Correct identification of the pests is critical for their successful management
Leaf diseases and their management in oats
No full textLeaf diseases of oats impact on grain yield and quality and reduce hay quality characteristics, such as colour and digestibility. This page outlines the symptoms, factors favouring disease risk and spread, and management.
Major leaf diseases of oats are septoria avenae blotch, stem rust, leaf rust, and barley yellow dwarf virus. Their severity changes with seasons
Loose smut of barley and its management
No full textThe fungal disease loose smut of barley parasitises the host plant and produces masses of soot-like spores that infect the seed head, reducing the yield and quality of harvested grain.
Smut diseases are host specific, meaning that smut of one cereal crop will not infect others (for example, loose smut of barley does not infect wheat or oats).
In many cases grain receival points have low or zero tolerance of smut contaminated grain
Russian wheat aphid and its management in wheat and barley
No full textRussian wheat aphid is found worldwide and has spread throughout all major grain growing countries. In Australia, Russian wheat aphid is present in South Australia, Victoria, New South Wales, Tasmania, and Western Australia, where it was first detected in 2020.
In Western Australia, Russian wheat aphid is found in low, medium, and high rainfall areas.
Presence of Russian wheat aphid in Western Australia is not an international trade issue and there are no trade implications for the grain industry, as bulk grain is not a host for Russian wheat aphid
Overcoming barriers to climate-smart agriculture in South Asia
No full textDespite the promise of climate-smart agriculture (CSA) to improve food security in South Asia, most CSA practices and technologies have not been widely adopted. We identify the key barriers to CSA adoption in South Asia and suggest strategies to overcome them to increase CSA adoption at scale
2025 Western Australian Crop Sowing Guide
No full textThe 2025 Western Australian Crop Sowing Guide has been compiled by officers of the Department of Primary Industries and Regional Development. It provides information to support variety decisions for each of the major crops for the upcoming season.https://library.dpird.wa.gov.au/bulletins/1297/thumbnail.jp