Disease under plant health rules · Kiwifruit
Kiwifruit bacterial canker (Psa): which vines to check first
Pseudomonas syringae pv. actinidiae
A bacterium that opens cankers on canes and trunk and can kill the vine. We fly the orchard and mark vines with dead canes, so you can check them on foot.
We have not flown this problem ourselves yet. We work it out with you, on your field.
The problem
A bacterium that arrives with the plant
In early spring a reddish or whitish liquid oozes from the cankers and wounds, and under the bark the wood is reddish. Buds and flowers wilt. In summer, dark, angular spots with a yellow halo appear on the leaf. Canes die and the fruit stops growing.
It advances fast in mild, damp weather, especially in early autumn and spring, and enters through frost wounds. It moves with pollen, nursery plants, pruning, wind and rain.
How it works
A flight to know what to check
1
We fly the orchard
In summer, when dead canes stand out against the green foliage.
2
We send you the map
Vines with dead canes or low vigour. We know of no drone study for Psa: what is seen is the dead cane, which can have other causes. It is confirmed on foot and in the laboratory.
3
You act
If in doubt, ask your adviser or your plant health service. Prune the diseased vine, cutting well beyond the damage, and disinfect the tool between vines.
Where it shows up
Where it appears
- Kiwifruit
What farmers ask us
Kiwifruit bacterial canker: field questions
Where does it start to show?
On the cankers and wounds in early spring, with a reddish liquid. In summer, on leaf spots with a yellow halo.
How do I avoid bringing it in?
With healthy nursery plants that come with their plant health documents. In many countries it is covered by plant health rules, so check what applies where you farm.
How do I prune an affected vine?
Cut well beyond the damage (infected wood extends further than the visible symptoms), destroy what you cut as your plant health service instructs, and disinfect the tool. Suspect vines last.
Know someone this would help?
Send them this page. If they have kiwifruit bacterial canker (Psa) in their fields, you save them some searching.