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Cotton growing landscapes in Australia have been dominated by dual-toxin transgenic Bt varieties since 2004. The cotton crop has thus effectively become a sink for the main target pest, Helicoverpa armigera. Theory predicts that there should be strong selection on female moths to avoid laying on such plants. We assessed oviposition, collected from two cotton-growing regions, by female moths when given a choice of tobacco, cotton and cabbage. Earlier work in the 1980s and 1990s on populations from the same geographic locations indicated these hosts were on average ranked as high, mid and low preference plants, respectively, and that host rankings had a heritable component. In the present study, we found no change in the relative ranking of hosts by females, with most eggs being laid on tobacco, then cotton and least on cabbage. As in earlier work, some females laid most eggs on cotton and aspects of oviposition behaviour had a heritable component. Certainly, cotton is not avoided as a host, and the implications of these finding for managing resistance to Bt cotton are discussed. [ABSTRACT FROM PUBLISHER]

In 1996, the Australian cotton industry adopted Ingard that expresses the Bacillus thuringiensis (Bt) toxin gene cry1Ac and was planted at a cap of 30%. In 2004-2005, Bollgard II, which expresses crylAc and cry2Ab, replaced Ingard in Australia, and subsequently has made up >80% of the area planted to cotton, Gossypium hirsntum L. The Australian target species Helicoverpa armigera (Hübner) and Helicoverpa punctigera (Wallengren) are innately moderately tolerant to Bt toxins, but the absence of a history of insecticide resistance indicates that the latter species is less likely to develop resistance to Bt cotton. From 2002-2003 to 2006-2007, F2 screens were deployed to detect resistance to CrylAc or Cry2Ab in natural populations of H. punctigera. Alleles that conferred an advantage against CrylAc were not detected, but those that conferred resistance to Cry2Ab were present at a frequency of 0.0018 (n = 2,192 alleles). Importantly, the first isolation of Cry2Ab resistance in H. punctigera occurred before significant opportunities to develop resistance in response to Bollgard II. We established a colony (designated Hp4-13) consisting of homozygous resistant individuals and examined their characteristics through comparison with individuals from a Bt-susceptible laboratory colony. Through specific crosses and bioassays, we established that the resistance present in Hp4-13 is due to a single autosomal gene. The resistance is fully recessive. Homozygotes are able to survive a dose of Cry2Ab toxin that is 15 times the reported concentration in field grown Boligard II in Australia (500 μg/ml) and are fully susceptible to CrylAc and to the Bt product DiPel. These characteristics are the same as those described for the first Cry2Ab resistant strain of H. armigera isolated from a field population in Australia. [ABSTRACT FROM AUTHOR]

Helicoverpa punctigera and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) are important pests of field and horticultural crops in Australia. The former is endemic to the continent, whereas the latter is also distributed in Africa and Asia. Although H. armigera rapidly developed resistance to virtually every group of insecticide used against it, there is only one report of resistance to an insecticide in H. punctigera. In 1996 the Australian cotton industry adopted Ingard, which expresses the Bacillus thuringiensis (Bt) toxin gene cry1Ac. In 2004/2005, Bollgard II (which expresses Cry1Ac and Cry2Ab) replaced Ingard and has subsequently been grown on 80% of the area planted to cotton, Gossypium hirsutum L. From 2002/2003 to 2006/2007, F2 screens were used to detect resistance to Cry1Ac or Cry2Ab. We detected no alleles conferring resistance to Cry1Ac; the frequency was <0.0005 (n = 2,180 alleles), with a 95% credibility interval between 0 and 0.0014. However, during the same period, we detected alleles that confer resistance to Cry2Ab at a frequency of 0.0018 (n = 2,192 alleles), with a 95% credibility interval between 0.0005 and 0.0040. For both toxins, the experiment-wise detection probability was 94%, i.e., if there actually was a resistance allele in any tested lines, we would have detected it 94% of the time. The first isolation of Cry2Ab resistance in H. punctigera was before the widespread deployment of Boilgard II. This finding supports our published notion for H. armigera that alleles conferring resistance to Cry2Ab may be present at detectable frequencies in populations before selection by transgenic crops. [ABSTRACT FROM AUTHOR]

Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) is an important lepidopteran pest of cotton (Gossypium spp.) in Australia and the Old World. From 2002, F2 screens were used to examine the frequency of resistance alleles in Australian populations of H. armigera to Bacillus thuringiensis (Bt) CrylAc and Cry2Ab, the two insecticidal proteins present in the transgenic cotton Bollgard II. At that time, Ingard (expressing CrylAc) cotton had been grown in Australia for seven seasons, and Boilgard H was about to be commercially released. The principal objective of our study was to determine whether sustained exposure caused an elevated frequency of alleles conferring resistance to CrylAc in a species with a track record of evolving resistance to conventional insecticides. No major alleles conferring resistance to CrylAc were found. The frequency of resistance alleles for CrylAc was <0.0003, with a 95% credibility interval between 0 and 0.0009. In contrast, alleles conferring resistance to Cry2Ab were found at a frequency of 0.0033 (0.0017,0.0055). The first isolation of this allele was found before the widespread deployment of Bollgard H. For both toxins the experiment-wise detection probability was 94.4%. Our results suggest that alleles conferring resistance to CrylAc are rare and that a relatively high baseline frequency of alleles conferring resistance to Cry2Ab existed before the introduction of Bt cotton containing this toxin. [ABSTRACT FROM AUTHOR]

Poster: Physics track: Treatment planning: applications PO-1464: Total body irradiation practice in Australia and New Zealand: Results of a Survey L. Fog, A. Wirth, M. MacManus, S. Downes, M. Grace, A. Moggre, K. Mugabe, G. Neveri, L. Nourbehesht, V. Panetieri, D. Pope, L. Sim, C. Stanton, B. Steer, A. Stewart, E. Ungureanu, T. Kron. [Extracted from the article]

The fall armyworm (FAW) Spodoptera frugiperda (Smith; Lepidoptera: Noctuidae) is present in over 70 countries in Africa, Asia, and Oceania. Its rapid dispersal since 2016 when it was first reported in western Africa, and associated devastation to agricultural productivity, highlight the challenges posed by this pest. Currently, its management largely relies on insecticide sprays and transgenic Bacillus thuringiensis toxins, therefore understanding their responses to these agents and characteristics of any resistance genes enables adaptive strategies. In Australia, S. frugiperda was reported at the end of January 2020 in northern Queensland and by March 2020, also in northern Western Australia. As an urgent first response we undertook bioassays on two Australian populations, one each from these initial points of establishment. To assist with preliminary sensitivity assessment, two endemic noctuid pest species, Helicoverpa armigera (Hübner; Lepidoptera, Noctuidae) and Spodoptera litura (Fabricius; Lepidoptera, Noctuidae), were concurrently screened to obtain larval LC50 estimates against various insecticides. We characterized known resistance alleles from the VGSC, ACE-1, RyR, and ABCC2 genes to compare with published allele frequencies and bioassay responses from native and invasive S. frugiperda populations. An approximately 10× LC50 difference for indoxacarb was detected between Australian populations, which was approximately 28× higher than that reported from an Indian population. Characterization of ACE-1 and VGSC alleles provided further evidence of multiple introductions in Asia, and multiple pathways involving genetically distinct individuals in Australia. The preliminary bioassay results and resistance allele patterns from invasive S. frugiperda populations suggest multiple introductions have contributed to the pest's spread and challenge the axiom of its rapid 'west-to-east' spread., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America.)

Aim: To review the expected increasing demand for cancer services among low and middle-income countries (LMICs) in the Asia-Pacific (APAC), and to describe ways in which Australia and New Zealand (ANZ) can provide support to improve cancer outcomes in our region., Methods: We first review the current and projected incidence of cancer within the APAC between 2018 and 2040, and the estimated demand for chemotherapy, radiotherapy and surgery. We then explore potential ways in which ANZ can increase regional collaborations to improve cancer outcomes., Results: We identify 6 ways that ANZ can collaborate with LMICs to improve cancer care in the APAC through the ANZ Regional Oncology Collaboration Strategy: Increasing education and institutional collaborations in the APAC region through in-country training, twinning partnerships, observerships and formalised training programs in order to increase cancer care quality and capacity. Promoting and assisting in the establishment and maintenance of population-based cancer registries in LMICs. Increasing research capacity in LMICs through collaboration and promoting high quality global oncology research within ANZ. Engaging and training Australian and New Zealand clinicians in global oncology, increasing awareness of this important career path, and increasing health policy engagement. Increasing web-based endeavours through virtual tumour boards, web-based advocacy platforms and web-based teaching programs. Continuing to leverage for funding through professional bodies, government, industry, not-for-profit organisations and local hospital funds., Conclusion: We propose the creation of an Australian and New Zealand Interest Group to provide formalised and sustained collaboration between researchers, clinicians and stakeholders., (© 2021 John Wiley & Sons Australia, Ltd.)

Introduction: The Asia-Pacific Special Interest Group (APSIG) was formed in 2009 by the Australian College of Physical Scientists and Engineers in Medicine (ACPSEM) to support radiation oncology services in low-to-middle income countries in our region. In 2017, APSIG moved to the ACPSEM's charity, the Better Healthcare Technology (BHT) Foundation, enabling improvement in fundraising, marketing and partnerships with like-minded organizations., Methods: APSIG's main activity is to recruit certified medical physicists as volunteers to train local staff in countries such as Vietnam, Cambodia, Myanmar and Mongolia. APSIG also supports remote mentoring, coordinates the delivery of donated radiotherapy equipment, and brings Asia-Pacific medical physicists to Australia and New Zealand for conferences and hospital training., Results: The number of APSIG volunteer assignments has been steadily increasing over the last decade. Challenges include the limited number of ACPSEM certified medical physics volunteers, the limited opportunities to train the local physicists due to their heavy workloads, and language barriers. The COVID-19 pandemic has halted volunteer assignments for now but a range of alternative means of assistance such as webinars, online tutorials and virtual meetings are planned to continue APSIG's activities., Conclusion: APSIG will continue to provide a support service to radiation oncology staff in the Asia-Pacific region. APSIG and the BHT Foundation's work promotes quality health care by supporting medical physicists in Asia-Pacific countries and championing better radiotherapy technology access and treatment knowledge sharing., (© 2021 The Royal Australian and New Zealand College of Radiologists.)

Total body irradiation (TBI) is an important treatment modality for the preparation of patients for bone marrow transplants. It is technically challenging and the actual delivery may vary from clinic to clinic. Knowledge of the pattern of practice may be helpful for clinics to determine future practice. We carried out an email survey from April to September 2019 sending 48 TBI related questions to all radiotherapy clinics in Australia and New Zealand via the Australasian College of Physical Scientists in Medicine email distribution list. Centres not performing TBI were not expected to complete the survey and centres that had participated in a previous survey, or that were known to perform the treatment, were followed up if no response was received. Of a total of approximately 70 centres, 14 clinics responded to the survey. The vast majority of clinics use conventional lateral and/or anterior-posterior beams at extended SSD for TBI treatment delivery. However, treatment planning, ancillary equipment (used for immobilisation/modulation), beam energy and prescribed lung doses vary considerably-with some clinics delivering the prescription dose to the lungs and some aiming to deliver a lung dose which is lower than the prescription dose. Only one clinic reported using an advanced delivery technique with modulated arcs at extended SSD. Centres either said they had no access to outcome data or did not answer this question. Compared with an earlier survey from 2005, 3 clinics have lowered their linac dose rate and 7 are the same or similar. The TBI practice in Australia and New Zealand remains varied, with considerable differences in treatment planning, beam energy, accepted lung doses and delivered dose rates.

Transgenic cotton expressing insecticidal proteins from Bacillus thuringiensis (Bt) has been grown in Australia for over 20 years and resistance remains the biggest threat. The native moth, Helicoverpa punctigera is a significant pest of cotton. A genotype causing resistance to Cry1Ac in H. punctigera was isolated from the field and a homozygous line established. The phenotype is recessive and homozygous individuals possess 113 fold resistance to Cry1Ac. Individuals that carry Cry1Ac resistance genes are rare in Australia with a frequency of 0.033 being detected in field populations. RNAseq, RT-PCR and DNA sequencing reveals a single nucleotide polymorphism at a splice site in the cadherin gene as the causal mutation, resulting in the partial transcription of the intron and a premature stop codon. Analysis of Cry1Ac binding to H. punctigera brush border membrane vesicles showed that it is unaffected by the disrupted cadherin gene. This suggests that the major Cry1Ac target is not cadherin but that this molecule plays a key role in resistance and therefore the mode of action. This work adds to our knowledge of resistance mechanisms in H. punctigera and the growing literature around the role of cadherin in the mode of action of Cry1 type Bt proteins.

Insecticides impose extreme selective pressures on populations of target pests and so insecticide resistance loci of these species may provide the footprints of 'selective sweeps'. To lay the foundation for future genome-wide scans for selective sweeps and inform genome-wide association study designs, we set out to characterize some of the baseline population genomic parameters of one of the most damaging insect pests in agriculture worldwide, Helicoverpa armigera. To this end, we surveyed nine Z-linked loci in three Australian H. armigera populations. We find that estimates of π are in the higher range among other insects and linkage disequilibrium decays over short distances. One of the surveyed loci, a cytochrome P450, shows an unusual haplotype configuration with a divergent allele at high frequency that led us to investigate the possibility of an adaptive introgression around this locus.

Prior to the widespread adoption of two-gene Bt cotton (Bollgard II®) in Australia, the frequency of resistance alleles to one of the deployed proteins (Cry2Ab) was at least 0.001 in the pests targeted namely, Helicoverpa armigera and Helicoverpa punctigera. In the 7 years hence, there has been a statistically significant increase in the frequency of alleles conferring Cry2Ab resistance in field populations of H. punctigera. This paper reviews the history of deploying Bt cotton in Australia, the characteristics of the isolated Cry2Ab resistance that likely impact on resistance evolution, aspects of the efficacy of Bollgard IIχ, and the behavioural ecology of Helicoverpa spp. larvae as it pertains to resistance management. It also presents up-to-date frequencies of resistant alleles for H. punctigera and reviews the same information for H. armigera. This is followed by a discussion of current resistance management strategies. The consequences of the imminent release of a third generation product that utilizes the novel vegetative insecticidal protein Vip3A are then considered. The area planted to Bt-crops is anticipated to continue to rise worldwide and many biotechnical companies intend to add Vip3A to existing products; therefore the information reviewed herein for Australia is likely to be pertinent to other situations., (Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.)

Bt cotton has been gradually released and adopted by Australian growers since 1996. It was initially deployed in Australia primarily to control the polyphagous pest Helicoverpa armigera (Hübner), which in the 1990s became increasingly difficult to control due to widespread resistance to synthetic chemical insecticides. Bt-cotton has become a key tool in a program of integrated pest management for the production system that reduces pesticide dependence and the problems associated with its use. Herein we overview the deployment of Bt cotton in Australia including its performance and the approaches used to prolong the evolution of resistance to it by H. armigera. An integral component of this approach is monitoring resistance in this pest. We outline resistance screening methods, as well as the characteristics of resistant strains of H. armigera that have been isolated from field populations, or selected in the laboratory. We then highlight the successes and challenges for Bt cotton in Australia by way of discussing adaptive resistance management in light of potential changes in resistance.

Combinations of dissimilar insecticidal proteins ("pyramids") within transgenic plants are predicted to delay the evolution of pest resistance for significantly longer than crops expressing a single transgene. Field-evolved resistance to Bacillus thuringiensis (Bt) transgenic crops has been reported for first generation, single-toxin varieties and the Cry1 class of proteins. Our five year data set shows a significant exponential increase in the frequency of alleles conferring Cry2Ab resistance in Australian field populations of Helicoverpa punctigera since the adoption of a second generation, two-toxin Bt cotton expressing this insecticidal protein. Furthermore, the frequency of cry2Ab resistance alleles in populations from cropping areas is 8-fold higher than that found for populations from non-cropping regions. This report of field evolved resistance to a protein in a dual-toxin Bt-crop has precisely fulfilled the intended function of monitoring for resistance; namely, to provide an early warning of increases in frequencies that may lead to potential failures of the transgenic technology. Furthermore, it demonstrates that pyramids are not 'bullet proof' and that rapid evolution to Bt toxins in the Cry2 class is possible.

Alleles conferring resistance to Cry2Ab toxin occur at a frequency of 0.0033 in Australian populations of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), and it is evident that detectable levels of resistance predated the introduction of transgenic cotton expressing this toxin. From 2002 until 2006, 10 such resistant alleles were scored. Here, we examine colonies established from five of the 10 isolates by using complementation tests to determine their genetic relationships. The results demonstrate that the resistance in each colony is due to alleles at the same locus and that for each allele the resistance is recessive. This latter finding is in conflict with the frequency of apparently resistant individuals occurring in the initial F2 tests that were used to identify alleles that confer resistance. These frequencies were variable (range 6.7-35.6%, mean 16.2%), but they generally indicated a measure of dominance (i.e., were >6.25% expected for recessive resistance). We hypothesize that this conflict is the result of differences in the genetic background of the laboratory adapted resistant colonies and the initial field isolations.

In the mid-1990 s the Australian Cotton industry adopted an insect-resistant variety of cotton (Ingard) which expresses the Bt toxin Cry1Ac that is specific to a group of insects including the target Helicoverpa armigera. A conservative resistance management plan (RMP), that restricted the area planted to Ingard, was implemented to preserve the efficacy of Cry1Ac until two-gene transgenic cotton was available. In 2004/05 Bollgard II replaced Ingard as the transgenic cotton available in Australia. It improves on Ingard by incorporating an additional insecticidal protein (Cry2Ab). If an appropriate refuge is grown, there is no restriction on the area planted to Bollgard II. In 2004/05 and 2005/06 the Bollgard II acreage represented approximately 80 of the total area planted to cotton in Australia. The sensitivity of field-collected populations of H. armigera to Bt products was assayed before and subsequent to the widespread deployment of Ingard cotton. In 2002 screens against Cry2Ab were developed in preparation for replacement of Ingard with Bollgard II. There have been no reported field failures of Bollgard II due to resistance. However, while alleles that confer resistance to H. armigera in the field are rare for Cry1Ac, they are surprisingly common for Cry2Ab. We present an overview of the current approach adopted in Australia to monitor and adaptively manage resistance to Bt-cotton in field populations of H. armigera and discuss the implications of our findings to date. We also highlight future challenges for resistance management in Australia, many of which extend to other Bt-crop and pest systems.

Introduction: The Indian Ocean Territories (IOT) comprising Christmas and Cocos (Keeling) Islands are situated over 2500 km from Perth, Australia, and are accessible by commercial aircraft only twice a week. The IOT Health Service (IOTHS) is administered from the Department of Transport and Regional Services in Canberra, ACT, Australia. Since 1998, all pregnant women have been required to leave the islands by 36 weeks gestation and travel to the mainland for birthing. Previously most women with low risk pregnancies were delivered on their island. Women and their partners regularly question medical staff as to reasons for the current obstetric service and, in particular, why they have to leave the Islands to give birth. While this is a common scenario in many remote parts of Australia, the vast distance involved and the cultural differences of the predominantly Chinese and Malay population make the IOT situation unique., Methods: A study was conducted during 2005 to determine the requirements for providing a safe, cost-effective and socially-acceptable obstetrics service, and to identify possible areas for improvement in the current service, and to explore potential solutions. This article presents one aspect of the study, involving qualitative analysis of recorded interviews with 28 of the islands' women., Results: Having choice about where the baby would be born was the most significant category of data analysis. In making choice, a number of variables come into play, including positive and negative social, economic, logistical and cultural factors related to the decision. Women were also strongly influenced by issues of safety, and their response to these issues was largely based on their previous experience and understanding of the IOT obstetric service., Conclusion: Many families expressed a desire for full obstetric services to be reinstated on the islands for low-risk pregnancies, particularly because of the difficulties they experience with the current service. Three recommendations were formulated in response to the social, economic, cultural and logistical difficulties faced by IOT women and their families.