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The bogong moth, Agrotis infusa, an endemic noctuid moth of Australia, is known for its extensive long‐distance movement and summer aestivation in the Australian Alps. Recent studies have focused on moth activity in the Alps, but there are limited data for other regions. This study aims to build on the current understanding of bogong moth movement and breeding patterns using unpublished historical data across eastern Australia. We analysed historical data from moth traps in Victoria, New South Wales (NSW) and South Australia (SA) from the 1960s to early 1990s. The study employed the HYSPLIT model for trajectory analysis of moth flight paths and DARABUG2 for phenological modelling. We examined moth catches across different seasons to infer movement patterns, breeding sources and over‐summering activity. Our findings question several long‐standing assumptions about the spatial ecology of the bogong moth. The trajectory analysis suggests that many aspects of A. infusa movement can be explained via dynamic migration, without fully relying on inherent navigation abilities. Important breeding areas may be beyond the self‐mulching clays of NSW and southern Queensland and include far western NSW, south and central SA and southern Victoria. Substantial moth activity during summer in many traps suggests alternative over‐summering strategies including local breeding or even aestivation in areas other than the Alps. Furthermore, the autumn and winter data imply return migrations from diverse source areas and potential local breeding, expanding the understanding of the moth's life cycle beyond a univoltine pattern. In conclusion, the bogong moth appears to exhibit a more complex and adaptable migration and breeding strategy than previously understood, utilising a range of habitats across eastern Australia for breeding and possibly aestivation. This underscores the need for a revised understanding of bogong moth ecology, which is crucial for its conservation and management, especially considering its recent classification as 'Endangered' on the IUCN Red List. [ABSTRACT FROM AUTHOR]

Pyrethroid resistance in the redlegged earth mite (Halotydeus destructor) continues to be a persistent and expanding problem across the grain belt of Australia, requiring ongoing monitoring to detect emerging local resistance issues. Detection of field resistance in H. destructor currently relies upon the collection and transport of live mites, followed by laborious experiments involving laboratory pesticide bioassays or fairly complex genetic screening assays. Both approaches require trained scientists and are time‐consuming and therefore do not provide rapid feedback to farmers. To facilitate the rapid detection of resistance issues, we developed a novel bioassay that can be readily applied in the field using commercially available materials and without the need for training. Although effective in detecting field resistance, this approach was found to be unsuitable in situations where the resistance allele frequency within a mite population was low. To address this limitation, we developed a loop‐mediated isothermal amplification (LAMP)‐based assay. This approach was successful in distinguishing between homozygote (SS) and heterozygote (RS) mites and, therefore, capable of detecting resistance at low frequency. These tools should help in the ongoing real‐time monitoring of resistance in this important agricultural pest. [ABSTRACT FROM AUTHOR]

Three species of polyphagous Liriomyza leafminers (Diptera: Agromyzidae), Liriomyza huidobrensis, L. sativae, and L. trifolii, are internationally significant pests of vegetable and nursery crops that have each been recently detected on the Australian mainland. Due to the early stages of these invasions in Australia, it is unclear how climatic conditions are likely to support and potentially restrict the distribution of these species as they expand into novel ranges and threaten agricultural production regions. Additionally, it is unclear how natural enemies, particularly parasitoid wasps, will mitigate the impacts of these pests. Here, we predicted the future establishment potential of L. huidobrensis, L. sativae and L. trifolii in Australia, as well as two cosmopolitan parasitoid wasps known to provide control of the flies in both field and glasshouse settings, Diglyphus isaea (Hymenoptera: Eulophidae) and Hemiptarsenus varicornis (Hymenoptera: Eulophidae). Global distribution data spanning 42 countries were compiled and used to validate a process‐based model of establishment potential based on intrinsic population growth rates. The modelling approach successfully captured the international distribution of the three Liriomyza species based on environmental variables and predicted the high suitability of non‐occupied ranges in Australia. The largely unfilled climatic niche available to these pests demonstrates the early stages of their Australian invasions and highlights locations where vegetable production regions are at particular risk. In addition to Australia, our results highlight many regions globally where L. sativae, L. trifolii and L. huidobrensis have the potential to spread in the future. Within Australia, D. isaea and H. varicornis are predicted to have a large spatial and seasonal overlap with each Liriomyza species and thus are expected to influence the future spread of these pests and play an important role in local pest management programs. [ABSTRACT FROM AUTHOR]

The Russian wheat aphid (Diuraphis noxia [Kurdjumov, Hemiptera: Aphididae], RWA) was first detected in Australia in 2016 and is threatening an annual cereal industry valued at nearly 10 billion AUD per annum. Considerable uncertainty surrounds the economic risk of D. noxia to Australian cereals, which limits cost-effective farm management decisions. Through a series of inoculated and non-inoculated field trials in 2018 and 2019 in south-eastern Australia, we generated a range of D. noxia pressure metrics under different growing conditions for barley, wheat, and durum wheat. Relative yield loss was best explained by the 'percentage of tillers with D. noxia' (%TwRWA) with 0.28% yield loss per percent of tillers with D. noxia, which is significantly lower than 0.46–0.48% for susceptible winter wheat varieties in dryland conditions in the United States. Highest infestation levels were typically reached around GS40–50. To develop an action threshold, we calculated the rate of increase in the %TwRWA through time at 0.021% per day per %TwRWA (with little variation across sites). This allowed prediction of the expected maximum %TwRWA based on observations post tillering (GS30) and the expected duration before GS50 is reached. For earlier growth stages (

BACKGROUND: The global pest spotted winged drosophila (Drosophila suzukii) continues to have a significant economic impact on fruit production in areas where it is established, in addition to newly invaded ranges. Management activities spanning national biosecurity responses to farm‐scale pest control are limited by the inability to predict the timing and severity of seasonal outbreaks of D. suzukii and its climatic drivers. RESULTS: Here, we compiled and analysed data on international seasonal abundances for D. suzukii under different climates, crop types and management contexts to improve the predictability of seasonal population dynamics. In relating seasonal abundances to environmental predictors, specifically temperature, we found strong negative effects of exposure to high and low temperatures during the preceding month. Unlike most regional studies on D. suzukii phenology that focus on temperature in the physiological development range, we show that thermal extremes better explain seasonal population fluctuations. CONCLUSION: Although trap catches remain an indirect measure of infestations and must be interpreted carefully in terms of crop risk, our results should support monitoring programmes through enhanced knowledge of the climatic factors affecting D. suzukii population activity. The negative impact of high temperatures suggests that late‐season management strategies focusing on manipulating crop microclimates to temperatures above 25 °C can reduce D. suzukii abundance. We show that early season abundance is modulated by climate, particularly the depth of cold extremes experienced in the preceding time interval. These associations may be further developed into early‐season crop risk forecasts to support monitoring programs. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Predicting biological invasions remains a challenge to applied ecologists and limits pre‐emptive management of biosecurity threats. In the last decade, spotted‐wing drosophila Drosophila suzukii has emerged as an internationally significant agricultural pest as it rapidly spread across Europe and the Americas. However, the underlying drivers of its global invasion remain unstudied, while countries like Australia, presently free from D. suzukii, require robust estimates of spread and establishment potential to aid development of effective preparedness strategies.Here, we analysed the ecoclimatic and human‐mediated drivers of the global invasion of D. suzukii to understand historical spread patterns and improve forecasts of future spread potential. Using a modular approach, climate‐driven population dynamics were linked in space via dispersal processes to simulate spread at continental scales. Combined with biological parameters measured in laboratory studies, the spread model was parameterized and validated on international spread data.Model accuracy was high and was able to predict 83% of regional presence–absence through time in the United States and, without further model fitting, 78% of the variation in the Europe incursion. Omitting human‐assisted spread from the model reduced predictability by over 20%, highlighting the large anthropogenic influence in this modern biological invasion. Economic activity (GDP) rather than human population density was more strongly associated with human‐mediated spread. Simulations predicted that eastern Australian coastal regions, particularly those near major cities with high economic activity, will result in the fastest spread of D. suzukii.Synthesis and applications. Incursions of Drosophila suzukii into Australia will have significant consequences for horticultural industries with the predicted speed of spread making eradication programs extremely difficult. However, the identified areas of significant fruit production, and high environmental suitability and economic activity will form a logical means for prioritizing industry preparedness. In light of our findings, a key component of preparedness strategies will be the ability of fruit producers to rapidly transition to effective management of D. suzukii. [ABSTRACT FROM AUTHOR]