New ACTIGARD Research on Gold Kiwifruit

Kiwifruit crop canopy

A collaborative research project was started in 2019 between Syngenta, Zespri and Plant & Food Research, initially on Hayward kiwifruit. 

The aim was to get a better understanding of the use of ACTIGARD® plant activator, post-harvest and what impact it had on Hayward vines when applied at this time.

Tony Reglinski, Senior Research Scientist at Plant & Food Research says, “The best way to understand the effect of ACTIGARD® in the post-harvest window is to look for changes in the defence gene expression in the ACTIGARD® treated vines compared with the untreated vines, where an increase in gene expression is likely to equate to an increase in protection against Psa.”

The initial study showed both early and late harvested Hayward vines were responsive to ACTIGARD®, highlighting the value in using ACTIGARD® post-harvest to help protect Hayward vines against Psa infection.

In the 2021, the research project was extended to Gold3 Kiwifruit to confirm if the same positive response from ACTIGARD® on Hayward was also expressed in Gold Kiwifruit.

This new research confirmed that a post-harvest application of ACTIGARD® induced an upregulation of defence ‘marker’ genes in Gold3, as also seen in Hayward vines.

These results support the use of well-timed ACTIGARD® applications post-harvest, to help protect Gold3 and Hayward vines against Psa infection.

Apply ACTIGARD® at 200 g/Ha (plus copper) immediately post-harvest as a foliar spray.  A second application can be made 21-days later provided the canopy is still mostly green.  

Take care to prevent spray drift onto unharvested fruit in adjacent blocks to avoid the risk of residues on fruit.

For more information click here to download the latest post-harvest Kiwifruit Technote for ACTIGARD®.