May 14 2019

May Monthly Update

Biocontrol workshops

Fresh tomato and indoor vegetable growers and industry people were invited to two workshops during March, in Clevedon and Lincoln, to discuss recent biocontrol research and new pest control ideas, with a particular focus on covered crops.

At the well-attended workshops, growers were asked to discuss the challenges they face in managing tomato-potato psyllid (TPP) and other greenhouse pests, and scientists presented recent research on the new TPP biocontrol agent Tamarixia triozae and other biocontrols. There was discussion on what future work is needed to support non-agrichemical pest management in the greenhouse.

Presentations were provided by:

  • Dr Shola Olaniyan, Bio-Protection Research Centre, Lincoln University
  • Professor Steve Wratten, Bio-Protection Research Centre, Lincoln University
  • Dr Melanie Davidson, Plant & Food Research (PFR)
  • Dr Sally Anderson, Vegetable Research and Innovation Board (VR&I)Prof Steve Wratten talking on biocontrols at Curious Croppers in Clevedon

Professor Wratten opened the workshops talking about pests and control methods, including soft options (such as soap), chemicals and biocontrols.  Dr Olaniyan presented research they had worked on for the past one and half years along with what’s planned next, saying “growers are some of the best scientists”. 

Glasshouse biocontrols research at the Bio-Protection Centre includes trials on Merlice tomato plants using the “natural enemies” Engytatus, Limonicus, Cleobora and Tamarixia, in combination with buckwheat as a source of food and shelter for the biocontrol agents.     From this work they produced a brochure titled “Biological control of the tomato-potato psyllid in New Zealand glasshouses”.  Copies are available by contacting TomatoesNZ or through the Bio-Protection Research Centre.

Future work could include: looking at the effectiveness of Cleobora on other tomato cultivars and capsicum; combining Tamarixia with other known natural enemies of TPP; researching Engytatus interactions; and looking at other natural enemies of TPP within New Zealand.

Potatoes agronomists attending the Lincoln workshop talked about some of the challenges that potato growers face in managing TPP and the Candidatus Liberibacter solanacearum (CLSo) or Zebra Chip disease in potato crops.   There followed a discussion on whether there could be other ways to control the impacts of TPP on crops by better controlling or managing spread of the CLSo itself, and that this was a possible area for future research.

TomatoesNZ is funding a three-year PhD at the Lincoln Bio-Protection Centre to continue the work on developing glasshouse biocontrols.

Dr Anderson provided an overview of the VR&I board’s research projects of relevance to covered cropping, including progress on the three-year Sustainable Farming Fund (SFF) funded Tamarixia release project, which is being conducted by Plant & Food Research.    

First year releases for the SFF project involved sites in Canterbury, Hawkes Bay and Clevedon, and Tamarixia overwintered successfully in two Hawkes Bay sites and in Canterbury.  Dr. Davidson from Plant & Food Research explained that the percentage parasitism of the Tamarixia recovered ranged between 4 – 40%.   Plant & Food Research also tracked how far Tamarixia had moved from its original release site with adults found 1.7km away in Hawkes Bay.  In Canterbury the wasp was found 60 metres away and more work is being done to see if it’s spread further.

Year two releases during 2018-19 focused on organic growers to help boost survival rates in non-insecticide environments.  The third year will extend the releases, and growers that are interested in releasing Tamarixia on their site are welcomed to make contact with Dr. Anderson.  

Guides on both releasing and then surveying for Tamarixia have been developed by Plant & Food Research.  The project is due for completion in 2020.

The workshop presentations and handouts can be downloaded from here.  Work on these projects is funded by the Sustainable Farming Fund, AGMARDT, and industry (TomatoesNZ, Potatoes NZ, Vegetables NZ, Tamarillo Growers NZ, Watties and the VR&I board).


Managing Spray Drift information

TomatoesNZ have updated information on managing spray drift including advice for applicators such as good spray application management guidelines, notification of use, decisions that will influence the potential for drift, and steps to take if you suspect a spray drift incident.

These documents are available to download from the members section, or by contacting Karen Orr.

Future work is planned to add to this with information on what steps to take if you see or smell real-time spray drift and how to manage plant growth issues after the event.


Conference and AGM 2019

The TomatoesNZ AGM will be held at 4:00pm on Wednesday 31st July, at Mystery Creek, Hamilton.

We would love to see you at the 2019 AGM and conference “Our Food Future” at Mystery Creek, Hamilton, 31st July – 2nd August.  There will be an exciting programme of speakers and practical demonstrations and networking opportunities.

To see more conference details and register, go to

TomatoesNZ will reimburse you for your conference registration (two people per levy paying member) a contribution to travel costs. A claim form will be posted to members in during May.

TomatoesNZ Board Elections

We are seeking nominations for the TomatoesNZ board. If you are interested or know someone who might be, please get in touch with Helen Barnes.

Primary Industries Summit

TomatoesNZ is supporting the Primary Industries Summit taking place in Wellington 1 & 2 July 2019.   Read more about this event at  A discount code is available registration rates for TomatoesNZ members if you’d like to attend – please contact Karen Orr.