Show simple item record Herron, Grant 2021-04-06T05:34:06Z 2021-04-06T05:34:06Z 2019-06
dc.description.abstract • Cotton aphid, two-spotted mite (TSM), banana or strawberry spider mite (SSM), cotton seedling thrips, western flower thrips (WFT) and green mirid were collected from Australian cotton growing regions. • TSM regularly showed discriminating dose survivors against bifenthrin (Talstar®) and abamectin (Agrimec®) but seldom propargite (Comite®) or etoxazole (Paramite® or Zeal®) and never diafenthiuron (Pegasus® as CGA140408). • Bifenthrin (Talstar®) and abamectin (Agrimec®) resistance detected in TSM was often at high frequency so may fail. The reason for this is not clear because pyrethroid use in cotton is limited and TSM do not fly so their immigration from sprayed crops other than cotton must be limited. It is speculated that the continuing increase in abamectin (Agrimec®) resistance is due to its use as a preventative treatment with mirid sprays. Mirid sprays are disruptive to beneficials so the inclusion of abamectin reduces the risk of subsequent mite flare. • SSM was the most found mite species in Australian cotton confirming anecdotal observations that the cotton mite complex has changed and is no longer TSM dominant. Additionally TSM was restricted to NSW only and bean spider mite (BSM) was not collected so remains absent from Australian cotton. • To allow resistance monitoring SSM baseline data was established for abamectin (Agrimec®), propargite (Comite®) and diafenthiuron (Pegasus® as CGA140408) and monitoring commenced but none was detected. • A DNA based method to identify SSM, TSM and BSM was developed and successfully deployed by Biosecurity Australia where it has been used to identify more than 2000 quarantine mite intercepts. • Cotton aphid was tested for pirimicarb (Pirimor®), OP-specific, pyrethroid, clothianidin (Shield®), diafenthiuron (Pegasus® as CGA140408), thiamethoxam (Actara or Cruiser®) and sulfoxaflor (Transform®) resistance. Interestingly pyrethroid resistance was often detected although it is not registered for this use in cotton and pirimicarb (Pirimor®) and OP-specific resistance was not detected so these chemicals can be used with confidence. Neonicotinoid survivors were detected in some strains but later thought vigour tolerant rather than resistant requiring discriminating dose adjustment to eliminate those false positives. • Methods to transport and culture green mirid were developed making resistance detection possible with established laboratory based bioassay technology. Green mirid was screened for fipronil (Maestro® or Albatross®) resistance using a molecular-based diagnostic and none was detected. • Neonicotinoid resistance was detected in cotton seedling thrips confirming anecdotal consultant / grower observations that seed treatments may not be working as well as they did. Unexpectedly WFT was the most abundant thrips found and worryingly spinetoram (Success® Neo)(the only registered control in cotton) resistance was detected in some strains. • Much effort was put into transitioning resistance detection away from conventional bioassay to DNA based techniques. To this end indoxacarb resistance in cotton bollworm Helicoverpa armigera was extensively studied via genotype-by-sequencing and a diagnostic developed. Unexpectedly a second resistance mechanism was found preventing practical use of that diagnostic. • A molecular diagnostic was successfully developed and deployed against TSM and etoxazole (Paramite® or Zeal®). • Molecular methods to detect neonicotinoid in cotton seedling thrips and spinetoram (Success Neo®) in WFT were developed but require further validation. en_US
dc.description.sponsorship Cotton Research & Development Corporation en_US
dc.publisher NSW DPI en_US
dc.relation.ispartofseries DAN1507;
dc.title The sustainable chemical control and resistance management of mites, aphids & mirids in Australian cotton, 2014-2019 en_US
dc.type Technical Report en_US

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search Inside Cotton

Advanced Search


My Account