Canterbury Potato Liberibacter Initiative (CPLI)

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Project Overview

Canterbury Potato Liberibacter Initiative, is a project created and funded by a committee of Canterbury growers and processors, with in-kind support from Potatoes New Zealand.

CPLI was formed in August 2021 by like-minded farmers and industry representatives to combat the devastating impact of the Liberibacter (Lso) bacterium which causes Zebra-chip in potato crops.

The issue is very clear and although the control measures and agronomy of Tomato Potato Psyllid (TPP) has made improvements, the incidence of Zebra Chip in the processing crop has increased and detection levels in potato fields have remained high.

It’s clear that current strategies and chemical programs are not solving or reducing the Zebra-chip impact for growers, seed growers and processors. The CPLI committee all agree there is a major knowledge gap with Lso. Although TPP is the carrier of Lso, Lso is affecting the quality of our potato crop.

CPLI Program summary

  1. Screening of TPP for resistance to commonly used contact insecticides.
  2. Screening of TPP for resistance to commonly used systemic insecticides.
  3. Screening of Systemic Acquired Resistance (SAR) products and antibiotics for efficacy on Liberibacter.
  4. Fertilization of potatoes with calcium propionate to prevent spread of Liberibacter
  5. Use of lures to attract and kill TPP to prevent their entry into potato crops.
  6. Use of biological control agents to manage TPP populations in both potato crops and in alternate / over-wintering hosts.
  7. Use of selected border planting to attract beneficial insects and limit Psyllid ingress into potato crops. 

Read more about the projects in Newsletter No.3 below.

Communication Plan

  • Weekly text of overview in Canterbury and weekly emails through Potatoes NZ of Growing Degree Day (GDD) Accumulation, there is a historic direct correlation between the earlier the date first psyllid numbers averaging 1 are found on sticky traps and the higher the average Zebra-chip level in that season’s potatoes. Although this is an overview guide for Canterbury you will be able to compare this to your own field sticky trap numbers to see where your crops sit in comparison.
  • Winter 2022 review of the past season and results and learnings.

CPLI Newsletter No.3 CPLI Grower Newsletter No. 3 Mar-2022 

CPLI Newsletter No.2 CPLI Grower Newsletter No.2 Dec-2021

CPLI Newsletter No.1 CPLI Newsletter No.1 Oct-2021

Click here to view CPLI Degree Day Graphs.

Research Reports

21853-C – Jessica Vereijssen – Tomato Potato Psyllid _ contact insecticide March 2022 FINAL

Images from PFR