Application for Field Release of Listronotus Appendiculatus Leconte
Total Page:16
File Type:pdf, Size:1020Kb
1 Application for field release of Listronotus appendiculatus LeConte (Coleoptera: Curculionidae) for the biological control of Sagittaria platyphylla (Engelmann) JG Smith and S. calycina Engelmann (Alismataceae) in Australia Nominating Organisation: Victorian Department of Jobs, Precincts and Regions (DJPR) Technical contact: Dr Raelene Kwong Biosciences Research AgriBio, La Trobe University, 5 Ring Rd, Bundoora, VIC 3083 Email: [email protected] 2 Contents 1 Executive summary ........................................................................................................ 4 2 Information about the Target species ............................................................................. 7 Taxonomy ............................................................................................................... 7 Sagittaria platyphylla (Engelmann) J.G Smith .................................................. 7 Sagittaria calycina Engelmann ......................................................................... 9 Close relatives native in Australia: ........................................................................ 11 Close relatives introduced to Australia: ................................................................. 12 Habitat .................................................................................................................. 15 Native geographic range and climatic and edaphic variation between sites within range. Limits to distribution where known. .......................................................... 15 Current Australian distribution ........................................................................ 15 Control Methods ................................................................................................... 17 Herbicides ...................................................................................................... 17 Other treatments ............................................................................................ 17 Response to other human manipulations .............................................................. 18 Importance ............................................................................................................ 18 Detrimental .................................................................................................... 18 Beneficial ....................................................................................................... 19 Legislation ............................................................................................................ 19 Stakeholder Consultation ...................................................................................... 19 Approval as target species for biological control ................................................... 20 History of biological control ................................................................................... 20 3 Information on the biological control agent ................................................................... 22 Taxonomy ............................................................................................................. 22 Biology and ecology of the species ....................................................................... 22 Native range of the agent ...................................................................................... 23 Related species and a summary of their host range .............................................. 23 Source of the agent ............................................................................................... 26 Climate compatibility ...................................................................................... 26 Genetic compatibility ...................................................................................... 26 Agent’s potential for control of the target(s) ........................................................... 27 Possible interactions, including conflicts-of-interest with existing biological control programs ......................................................................................................................... 29 Information on where, when and how initial releases would be made ................... 29 3 Information on whether this species has established invasive populations, and if so, where those populations are ............................................................................................ 29 Information on the results of any other environmental risk assessments undertaken on the species in Australia and overseas ......................................................................... 29 Details on the quarantine facility and methods on containment ............................. 29 4 Information on non-target organisms at risk from the agent ......................................... 30 Test list for determining the host-specificity of Listronotus appendiculatus ............ 30 Materials and Methods .......................................................................................... 35 Trial 1. Adult no-choice and choice-minus-target oviposition trials ............................... 35 Trial 2. No-choice whole-plant adult oviposition and larval survival trials on native species ........................................................................................................................ 36 Trial 3. No-choice whole-plant larval development trial................................................. 37 Trial 4 Continuation trial ............................................................................................... 38 Trial 5. Achene predation trial ...................................................................................... 38 Native range studies .................................................................................................... 38 Statistical analyses ...................................................................................................... 39 Overall assessment of the reproductive rate of L. appendiculatus on single plant species over multiple generations ............................................................................................. 39 Overall assessment of plant damage ........................................................................... 41 Results .................................................................................................................. 43 Trial 1. Adult no-choice and choice-minus-target oviposition container trials ................ 43 Trial 2. No-choice whole-plant adult oviposition and larval survival trials ...................... 45 Trial 3. No-choice whole-plant larval development trial................................................. 45 Trial 4. Continuation trial .............................................................................................. 46 Overall assessment of the reproductive rate of L. appendiculatus on single plant over multiple generations ..................................................................................................... 48 Overall assessment of plant damage ........................................................................... 49 Trial 5. Achene predation trial ...................................................................................... 53 Native range studies .................................................................................................... 53 5 Discussion ................................................................................................................... 56 6 Conclusion ................................................................................................................... 60 7 References .................................................................................................................. 60 8 Supplementary Material ............................................................................................... 64 4 1 Executive summary Sagittaria platyphylla and Sagittaria calycina (Alismataceae) are emergent aquatic herbs native to north America that have become serious weeds of shallow ephemeral or permanent water bodies, in natural and ruderal habitats. In Australia, S. platyphylla extends from the tropical (Townsville) to the temperate regions of New South Wales, Australian Capital Territory, Victoria, South Australia and Western Australia. It is a serious invader of irrigation channels and drains in south-eastern Australia, forming dense monocultures that impede water flow, increasing risk of flooding and damaging irrigation infrastructure. In natural waterways, extensive infestations threaten native biodiversity and potentially impede the movement of native fish. Sagittaria calycina is much less widespread than S. platyphylla and is currently only present in NSW where it is a major crop competitor in rice crops of the Murrumbidgee and Coleambally irrigation areas, causing yield reductions of up to 75%, increased production costs and reductions in rice quality. Few effective options are available for the management of S. platyphylla and S. calycina, particularly in sensitive aquatic habitats or where off- target damage to horticultural and rice crops is a concern. Sagittaria platyphylla and S. calycina were declared targets for biological control in Australia in November 2015 after an in-depth biogeographical study on the genetic, demographic and herbivory differences between native USA and invasive Australian populations concluded that the prospects for successful