An integrated approach to manage pests and resistance to phosphine in stored grain (3036)

Transcription

1 An integrated approach to manage pests and resistance to phosphine in stored grain (3036) Dr M.K. Nayak (Queensland Department of Agriculture and Fisheries), Dr R. Kaur (Queensland Department of Agriculture and Fisheries), Dr G.J. Daglish (Queensland Department of Agriculture and Fisheries), Dr P.J. Collins (DAFQLD), Mr R. Reid (GrainCorp), Dr. R. Jagadeesan (Queensland Department of Agriculture and Fisheries), Mrs H. Pavic (Queensland Department of Agriculture and Fisheries), Mr L. Smith (Queensland Department of Agriculture and Fisheries), Mrs L. Bond (Queensland Department of Agriculture and Fisheries). Over a significant period of time, the Australian grain industry has been relying heavily on the fumigant phosphine to disinfest grain stored both on farm and the central storages. This over-reliance on a single fumigant, however, has resulted in the development of strong levels of resistance in major pest species. Of these, the resistance level detected recently in the rusty grain beetle, Cryptolestes ferrugineus had been characterised as the strongest ever resistance detected for phosphine in any stored grain pests. This has put enormous pressure on the industry in that the current phosphine label rates have failed to control the strongly resistant rusty grain beetle populations. Phosphine is the cheapest and most versatile fumigant around and most importantly, considered as a residue-free treatment worldwide. Therefore, it is imperative that the viability of phosphine as a Presenting author s biography key fumigant be maintained through effective resistance management for sustainability of market access of Australian grain. PBCRC3036 aimed at establishing alternative strategies to combat the phosphine resistance issue. These include development of sulfuryl fluoride as an alternative fumigant, alongside modifying the current fumigation protocols of phosphine. Fumigation protocols developed in the laboratory are being validated through large scale field trials in collaboration with GrainCorp. We present here the latest developments on effective fumigation protocols of sulfuryl fluoride and phosphine towards managing strongly phosphine resistant rusty grain beetles. The utility of an eradication strategy involving the available tools in an integrated way to combat resistance problems will also be discussed. Dr Manoj Nayak is a Principal Research Entomologist, currently Leader of the Post-harvest Grain Protection Team of the Department of Agriculture, Fisheries and Forestry, Brisbane, Queensland. With over 20 years of experience in post-harvest grain biosecurity, Manoj s main research interests include development of grain protectants, phosphine efficacy, development of alternative fumigants such as sulfuryl fluoride, resistance management and integrated pest management in stored grain and processed food. Apart from being part of several Grains Research and Development Corporation projects and an ACIAR project as a lead researcher, Manoj has successfully led six CRCNPB research projects. He currently leads two PBCRC projects aimed at managing resistance to phosphine in key stored grain pests and developing sulfuryl fluoride as an alternative fumigant. Research outputs from these projects have delivered practical solutions to ongoing pest and resistance incursions that are being adopted by the grain industry and help maintain its market access. Dr Manoj Nayak manoj.nayak@daff.qld.gov.au Science Exchange 2015 Conference Handbook 15

2 Session One: Better management of established pests Presentation title: An integrated approach to manage pests and resistance to phosphine in stored grain Presenter: Manoj Nayak

3 PBCRC3036: An integrated approach to manage pests and resistance to phosphine in stored grain Dr Manoj Nayak Principal Research Scientist Department of Agriculture and Fisheries, Queensland Plant Biosecurity Cooperative Research Centre

4 Background Project initiated in 2009 Research Team: DAFQ - Manoj Nayak, Ramandeep Kaur, Greg Daglish, Pat Collins, Lawrence Smith, Linda Bond, Virgin Singarayan NSWDPI - Jo Holloway, Rachel Wood GrainCorp - Robin Reid and team Viterra - Greg Hopkins and team CYTEC Justin Tumambing

5 Problem being addressed Development of strong resistance to phosphine in rusty grain beetle (Cryptolestes ferrugineus) Resistance level highest detected so far Current fumigation protocols failed No suitable alternatives available Market access under threat Industry pressed for new treatments

6 Problem being addressed

7 Problem being addressed

8 The Approach Developing Sulfuryl fluoride (SF) as a resistance breaker Developing higher fumigation rates (concentration x time) for phosphine Validate new protocols through industry-scale field trials Determine time to reinfestation after fumigation Develop an eradication strategy for rusty grain beetles

9 Results so far new phosphine protocols

10 Results so far proposed changes to phosphine label

11 Results so far field validation 12 days at 1080 ppm (1.5 mg/l) 2600 m 3 free standing silo at Millmerran, QLD 1996 t of APH2 wheat Applied as Cylinderised phosphine (ECO 2 Fume) Re-circulation fans used 4340 gms of phosphine Mixed-age of strongly resistant RGB, LGB, RFB, RW Assessment: - Adult mortality immediately after fumigation - emergence of adults - after 8 weeks

12 Results so far field validation Target concentration: 1080 ppm Temperature: Top : (avg: C) Bottom : (avg: C) Control : (avg: C) Relative Humidity: Top : (avg: 55.95%) Bottom : (avg: 41.65%) Control : (avg: 40.83%)

13 Results so far field validation Survivors of RGB at the top phosphine concentration dropped below the targeted concentration New protocols give industry flexibility New protocols developed for RGB - much higher than the current label rates Changes in current label needed More field validation required Ensures phosphine s future as an effective fumigant

14 Results so far SF protocols

15 Results so far a comparative assessment

16 Results so far - Time and temperature has significant effect on the effectiveness Time is more critical than concentration At 4 days-registered rate (1500 CT) at 25 C fails against RFB and RW Half the concentration of SF is required at 30 C than 25 C Minimum of 7 days exposure period control of all four pests Confirmatory experiments - on going Field validation (on farm and central bulk storages) - required

17 Results so far field validation of SF protocols Bunker (87m long and 37m wide) 8000t of AUH2 wheat Pre and post fumigation assessments of natural infestations SF 40 g/m3 (7-8 entry points) Target CT: 1500 (highest registered rate)(>10days) Full clearance of gas a month later

18 Results so far time to reinfestation

19 Results so far SF field validation SF fumigation successfully controlled all pest spp. Most important outcome: control of SR-RGB No live infestation detected for 4 months No survivors from the original infestation Re-infestation (invasion) did not occur Top of bunker favoured for infestation (dominated by C. ferrugineus and Psocids)

20 Results so far eradication strategy Use of Sulfuryl fluoride At ports, Methyl Bromide? Isolate infested grain, apply contact insecticide (eg., Reldan) Consider treating next season s grain (at least 6 mo protection) Intensive hygiene program Detailed cleaning and structural treatments Continue inspection, insect trapping and R-testing

21 The impact on current trend in STR RGB SF Number of STR populations

22 Who will use research? Grain Bulk Handling Companies (GrainCorp, CBH, Viterra) Farmers, grain processors Decision making bodies pest and resistance management strategies Grain Biosecurity Officers/Agronomists (extension network) Researchers in government departments, private research organisations and universities Chemical companies

23 Who will directly benefit from the research? Grain Bulk Handling Companies (GrainCorp, CBH, Viterra) Farmers, grain processors GRDC (representing growers) Grain Biosecurity Officers/Agronomists (extension network) Chemical companies

24 Challenges and issues arising from the research Use of SF should be monitored Judicious use - in cases where RGB are problematic Farmers should be discouraged to use SF unless they have a problem! Resistance monitoring protocols established now Rotation of phosphine (to reduce selection pressure) Phosphine will be useful Changes in label needed Field validation of more protocols needed Field trials happening next week!

25 Impact delivery plan National Resistance Management Strategy - network of pest and resistance managers, researchers GRDC National Extension Network National Working Party on Grain Protection Industry Workshops/Field Days Scientific and extension publications - Peer-reviewed journal papers - GRDC Publications (eg. Growers Update, Ground Cover)

26 Recent publication

27 The End-User Advocate s perspective Close collaboration between industry and researchers Industry has flexibility to use treatments Strategic direction on performance of resistance management strategy Information used to decide on treatments and storage performance Residue and environmental issues need to be addressed Information to biosecurity officers and extension networks Timely containment and eradication of resistant pest populations Confirmation of eradication Enhanced knowledge on incidences and selection for resistance to phosphine, utility of SF as a new tool

28 Thank you For more information, please