Research lays groundwork for improved TPP management
New research into the Tomato potato psyllid (TPP) has laid the foundations to help growers respond more effectively to the plant pest.
TPP was first detected in Western Australia in early 2017.
Research and development is critical to improving our scientific understanding of TPP and what management options are the most effective for Australian growing conditions.
The Department of Primary Industries and Regional Development recently completed the nine-month research program as part of its role in the national TPP transition to management plan.
The TPP R&D program included:
- screening toxicity of chemicals registered in Australia for other pest species, against TPP
- screening the potential of commercially-available biological control agents (BCAs)
- evaluating the efficacy of insecticides in conjunction with BCAs
- evaluating effectiveness of ethyl formate against TPP and phytotoxicity on host fruits
- a review of available literature to identify practical management strategies currently used where TPP is present elsewhere in the world, and to identify R&D knowledge gaps relevant to Australian conditions.
While there are a number of positive results from the desktop studies, laboratory and glasshouse trials, further work in the field is needed to validate this research.
TPP R&D results snapshot
1. Insecticides – laboratory trials
- A list of 15 potential insecticides including Abamectin (Vertimec®), Cyantraniliprole (Benevia®), Spirotetramat (Movento®), Flonicamid (Mainman®), Spinetoram (Success®), Sulfoxaflor (Transform™), Methidathion (Suprathion), Methomyl (Methomyl 225), Chlorpyrifos (Chlorpyrifos 500EC), DC-164 (experimental chemical of Bayer Crop Science), Imidaclorpid (Confidor® 200SC), Eco-Oil®, AGRI-50NF, Paraffinic oil (SACOA BioPest), Azadirachtin (Azamax)) were tested in laboratory bioassays for their toxicity against TPP life stages (eggs, nymphs, adults) in capsicum, tomato and potato.
- These chemicals are registered in Australia for use against other sucking insect pests in capsicum, tomato, potatoes and other crops, but not currently registered for control of TPP. Field data will be required to support registration by the Agricultural Pesticides and Veterinary Medicines Authority.
- 14 insecticides were tested as foliar application, and one (imidacloprid) was tested as soil drench.
- Abamectin, spinetoram, methidathion, methomyl, chlorpyrifos, cyantraniliprole, DC-164 (experimental chemical) and sulfoxaflor are very toxic and caused 100% mortality to the TPP life stages.
- Spirotetramat is a slow acting chemical requiring longer time to cause significant TPP mortality.
- Cyantraniliprole and flonicamid are less toxic to TPP young nymphs (1st-2nd instar).
- All plant-based derivatives (azadirachtin, eco-oil, agri-50 and paraffinic oil) are the least toxic to TPP matured nymphs (3rd-5th instar).
- Azadiractin is very toxic to TPP adults. Spirotetramat, flonicamid, paraffinic oil, agri-50 and eco-oil in potato and capsicum are less toxic to TPP adults. Egg laying was observed with agi-50, eco-Oil, paraffinic oil, flonicamid and spirotetramat in all plant types but none hatched after seven days.
- Of 13 chemicals tested against eggs, hatching was observed with spirotetramat, abamectin, methomyl, chlorpyrifos, eco-oil, paraffinic oil and azadirachtin, but none developed to adult.
- Imidacloprid soil drench is toxic to TPP life stages causing significant mortality for up to 10 days post drench.
- To prevent insecticide resistance from developing in TPP populations, insecticides from different chemical classes need to be used in rotation.
- Growers are encouraged to contact their chemical advisors to talk through an appropriate Insecticide Resistance Management strategy for their own business.
- Insecticides are only effective against TPP and do not prevent the spread of CLso.
2. Biological control agents (BCA) – laboratory trials
- Nine species of commercially-available BCAs were trialled, including six species of ladybird, an anthocorid bug, a mirid and a lacewing.
- The lab trials indicate all BCAs will feed on TPP, but that some are more voracious feeders than others.
- These initial results indicate more research is required to determine the most suitable biological control agents for TPP in different crops and growing conditions.
3. Efficacy of insecticides with BCA’s against TPP in capsicum, tomato and potato – glasshouse trials
- Three applications, at 21 day intervals, of abamectin, cyantraniliprole and spirotetramat in capsicum, tomato and potato, and flonicamid in tomato, effectively suppressed TPP populations
- Three releases at 21 day intervals, of mirid bug (Nesdiocoris tenuis) in tomato effectively suppressed TPP populations in the glasshouse trial.
4. Post-harvest disinfestation – laboratory trials
- DPIRD has identified a potential benefit in combining post-harvest disinfestation treatment for Mediterranean fruit fly and TPP for tomato, capsicum and eggplant.
- Ethyl formate controlled eggs, nymphs and adults of TPP. Eggs were the most tolerant, requiring a higher concentration of 0.5 to 2% ethyl formate.
- Ethyl formate did not cause phytotoxicity to chilli, cherry or round tomato, eggplant or capsicum at the maximum rate of 2%.
Further results from the R&D program will be provided to industry over the coming weeks.
The transition to management phase has provided a boost to TPP R&D in Australia and will continue to grow as the national R&D program is progressed through the role of national TPP coordinator.
TPP pre-harvest control options
Growers are reminded there are a number of pre-harvest control options currently available to assist with the management of TPP.
Emergency permits from the Australian Pesticides and Veterinary Medicines Authority (APVMA) have been made available for use in host crops and nursery stock.
Download permits at
Growers have a responsibility to ensure chemicals are used according to the label/permit instructions.
Find out more
Search 'TPP' on the department’s website for more information.
For more information contact Sonya Broughton, Senior Research Officer, South Perth on +61 (0)8 9368 3271.