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Simple Summary: Australian horticulture is at risk from incursions by exotic tephritid fruit fly species, particularly oriental fruit fly. An incursion by exotic fruit flies is likely to result in global trade restrictions and will cause significant economic losses. In this study, we investigated global management strategies for exotic fruit fly species and compared them with available local strategies in Australia to identify areas where Australian management practices could be improved. We identified that although Australia has a good understanding of the main exotic fruit fly threats, there remains no species-specific emergency response plan available to implement in the case of an incursion. Australia has effective tools for exotic fruit fly detection, an early warning surveillance network is in place across Australia and control measures used successfully for eradication elsewhere are available in Australia. However, the speed at which Australia could respond to an incursion is currently limited by the lack of a response plan, and this could have major implications for the effectiveness of management strategies for containment and eradication, likely leading to a more severe and costly incursion outcome. Exotic tephritid incursions are of high concern to Australia's biosecurity and its horticultural industries. It is vital that Australia remains ready to respond to incursions as they arise, as an incursion of tephritid fruit fly species will result in significant economic losses. In this review, we compared Australian incursion management strategies for fruit flies with global management strategies and identified possible areas where improvements could be made in an Australian context. Overall, Australia has a good understanding of the main tephritid threats, of which Bactrocera species from across the Torres Strait (northern Australia) are of most concern. Effective tools for tephritid detection and early warning surveillance at points of entry are in place at ports and in horticultural areas Australia-wide and provide the basis for initiating biosecurity responses in the event of an incursion. Area-wide control measures used in successful eradication attempts globally are available for use in Australia. However, a specific tephritid emergency response plan identifying suitable response measures and control options for species of concern is not yet available. We have identified that Australia has the policies and management tools available to respond to an exotic tephritid incursion, but the speed at which this could be accomplished would be greatly improved by the development of species-specific emergency response plans. [ABSTRACT FROM AUTHOR]

BACKGROUND The common armyworm Mythimna convecta is an important pest of pastures and graminaceous crops in Australia, but materials currently registered for its control are limited to broad‐spectrum compounds incompatible with integrated pest management (IPM) systems. In this study we assessed the response of M. convecta larvae to four alternative compounds using topical and dietary bioassays. RESULTS: Emamectin benzoate [LC50 (lethal concentration for 50% of insects tested) values 2.69 μg mL−1 topical, 0.017 μg active ingredient (AI) g−1 dietary] and chlorantraniliprole (LC50 values 4.87 μg mL−1 topical, 0.080 μg AI g−1 dietary) were significantly more active than either indoxacarb or cyantraniliprole. Our results showed strong parallels with data on the more extensively studied Australian strains of Helicoverpa armigera, with the most notable differences being the higher contact toxicity of emamectin benzoate to M. convecta and the lower acute dietary activity of formulated cyantraniliprole to this species, which was linked to feeding deterrence. Cyantraniliprole at dietary concentrations of ≥0.02 μg AI g−1 significantly reduced the weight of surviving larvae and frass production (an indirect measure of food consumption) over the seven‐day exposure period. There was also some evidence of chlorantraniliprole deterring larval feeding, although to a much more limited extent. CONCLUSIONS: Both emamectin benzoate and chlorantraniliprole are suitable for use against M. convecta. The decision as to which of these compounds should be prioritized for further development should be based on their potential effects on beneficial species once their optimal field rates have been determined. [ABSTRACT FROM AUTHOR]

Background: Integrating fungal biocontrol agents into crop protection programs dominated by synthetic pesticides is an important first step towards developing an integrated pest management (IPM) program; however, their successful integration relies on an understanding of how their performance may be impacted by the remaining agrochemicals deployed for managing other pests and diseases. In this study we tested 10 formulated pesticides used in macadamia production at different concentrations to determine their effects on the germination, mycelial growth and sporulation of Metarhizium anisopliae and Beauveria bassiana in vitro. Further tests with laboratory‐grade actives of the noncompatible pesticides were conducted to determine whether any antagonistic effects were caused by the active constituent or by formulation additives. Results: At their registered concentrations, formulated trichlorfon, acephate and indoxacarb were compatible with M. anisopliae, whereas B. bassiana showed compatibility with formulated trichlorfon, acephate, indoxacarb, sulfoxaflor and spinetoram. Bioassays using laboratory‐grade active constituents indicated that the adverse impact of formulated beta‐cyfluthrin on both fungal species and that of formulated methidathion on B. bassiana is probably due to components of the emulsifiable concentrate formulations rather than their active constituents. Diazinon was the only insecticidal active that showed high toxicity to both fungal species. The two fungicides, carbendazim and pyraclostrobin, were toxic to both fungal species at all tested concentrations. Conclusion: Our results identify which pesticides used on macadamias in Australia are compatible and incompatible with entomopathogenic fungi. Future studies on pesticide degradation rates will help define the spray intervals required to eliminate these adverse effects. [ABSTRACT FROM AUTHOR]

The citrus gall wasp (CGW), Bruchophagus fellis (Girault) (Hymenoptera: Eurytomidae), is a serious pest of citrus in southern Australia. Severe infestations can result in yield loss and a reduction in fruit size. Several parasitoid species attack CGW, with Megastigmus brevivalvus (Girault) (Hymenoptera: Torymidae) (MBV) being the dominant species. Both CGW and MBV are univoltine and adult wasps emerge from galls in the spring. Median emergence of MBV lags behind that of CGW by 2–3 weeks. We modelled the effect of spray timing for foliar-applied, non-systemic insecticides on the relative exposures of CGW and MBV based on their emergence distributions and estimated the optimal spray timing that maximises the control of CGW while minimising the impact on MBV. Three temporal emergence distribution scenarios for the two species and 28 periods of residual insecticide activity were considered in the investigation. The results showed that the optimal spray timing was always before the peak emergence of CGW. Depending on the residual activity of the insecticide, the optimal spray date pre-dated the peak emergence of CGW by 1–24 days, with longer lead times for insecticides with longer residual activity. By contrast, the optimal spray date varied little across the different emergence scenarios, suggesting that the results apply over a wide range of locations and seasons. A single insecticide application at the optimal timing may not guarantee satisfactory control of CGW. When the residual activity of the insecticide is short, multiple applications with a combined residual activity of 16 days are needed to ensure insecticide contact with ≥90% of all CGW that emerge in a season. • Median emergence of the citrus gall wasp occurs 2–3 weeks before that of its primary parasitoid. • Effects of spray timing on the relative exposure of the gall wasp and the parasitoid were modelled. • Optimal spray timing is 1–24 days before peak host emergence. • Appropriate spray scheduling can expose most gall wasps to insecticides whilst minimising impacts on the parasitoid. [ABSTRACT FROM AUTHOR]

The citrus gall wasp, Bruchophagus fellis, is a serious pest of citrus in southeast Australia and the ability to accurately predict its highly synchronised adult emergence periods is critical for its effective management. We monitored emergence of the citrus gall wasp for six years during 2010–2017 in southern Australia, yielding a total of 22 site-by-year datasets from two citrus production regions and multiple citrus varieties. For each dataset, the proportions of emerged wasps on different monitoring dates were related to the corresponding degree-days using a 2-parameter Weibull function. The two degree-day parameters, the lower development threshold temperature and biofix date, were estimated at 8 °C and August 1 respectively by cross-validation of a series of candidate values using the sum of squared differences between the predicted and observed median emergence dates as the performance indicator. According to the final fitted Weibull function, 5, 50, and 95% emergence occur when 560, 723 and 835 degree-days above 8 °C have accumulated after August 1. The predicted median emergence dates differed from the corresponding observed median emergence dates by an average of 2.8 days across the 22 datasets. The average deviations for 5 and 95% emergence were slightly larger, at five and four days, respectively. Observed degree-days for median emergence did not differ significantly between the two citrus production regions, indicating there is no need for separate degree-day models for different regions. Based on the degree-day model, an interactive, online timing tool has been developed, allowing growers to use local weather station data to predict when the gall wasp is likely to emerge in average, warm, and cool years. • A degree-day model was developed for the emergence of the citrus gall wasp. • 50% emergence occurs when 723 DD above 8 °C have accumulated after August 1. • Average prediction accuracy is ±2.8 days across 22 datasets. • An online tool was published to help citrus growers time their control operations. [ABSTRACT FROM AUTHOR]

• Both Metarhizium anisopliae and Beauveria bassiana are highly pathogenic. • Indigenous isolates performed as well as commercially available entomopathogens. • Entomopathogens in the future can be integrated into IPM programs. Macadamia seed weevil, Kuschelorhynchus macadamiae Jennings and Oberprieler, is a major pest of macadamia in eastern Australia, causing yield losses of up to 15%. Current control methods involve two applications of acephate per season but more recently have moved to a single application of indoxacarb, combined with the collection and destruction of fallen nuts that contain developing larvae. As a first step towards reducing the dependence of the industry on synthetic insecticides, we tested six isolates of M. anisopliae, six isolates of B. bassiana and one commercial B. bassiana product (Velifer® biological insecticide) against adult macadamia seed weevil under laboratory conditions. All isolates were pathogenic against adult weevils with M. anisopliae accession ECS1/BRIP 70272 and B. bassiana accession B27/BRIP 70267 causing 97.5% and 92.5% mortality 12 days after being treated at 1 × 107 conidia/mL. Isolates ECS1/BRIP 70272 and B27/BRIP 70267 had the shortest LT 50 values of 5.13 days and 5.37 days respectively. The median lethal concentrations (LC 50) for ECS1/BRIP 70272 and B27/BRIP 70267 were 1.48 × 105 and 1.65 × 105 conidia/mL respectively. Results of this study indicate that M. anisopliae accession ECS1/BRIP 70272 and B. bassiana accession B27/BRIP 70267 have considerable potential for K. macadamiae control, and should be developed into biological insecticides for integration into macadamia pest management programs. [ABSTRACT FROM AUTHOR]