Two conferences were dedicated to the Psa-Pseudomonas syringae pv actinidiae and the new possible solutions to live with it at Macfrut 2014: "Operative instructions to contain bacteriosis", promoted by Iko-Hydro srl and "Bacteriosis: coexistence is possible", held on 26th September.
"You must not make the mistake of thinking that there is no Psa, even if you don't see the symptoms for a while: we must learn how to live with it. There exist various solutions to contain the disease - in addition to good management practices, research is working on new machinery and pesticides," explained Marco Scortichini from Caserta's CRA.
Marco Scortichini during his intervention at Macfrut.
Bacteriosis must be defeated with fire
As is known, Psa can also spread through affected prunings, so Officine Mingozzi together with Ferrara's CSO have created a machine for fire pruning.
"We studied how long prunings have to burn to eliminate the bacteria: 2-4 seconds are enough for 3-5 cm branches," explained Trentini. The machinery was created by re-applying the technology already used on asparagus.
"It is basically a shredder with a burner: the shredder cuts the wood into very small pieces and the burner eliminates them, and therefore the infection. No damage is done to the grass underneath as, while it is true that the temperature is high, exposure times are too short to burn it."
The second conference. Left to right: moderator Elisa Lupotto (CRA), Luciano Trentini (CSO), Marco Mingozzi (Officine Mingozzi), Loredana Antoniacci (Servizio Fitosanitario dell'Emilia-Romagna) and Marco Scortichini (CRA).
"Of course this does not solve all problems, but it helps as it sterilises the ground too, making a relapse more difficult," added Marco Mingozzi.
New uses for old substances: chitosans
Research is also working on medicines to cure affected plants. Chitosans could represent a solution - a family of substances discovered 150 years ago and used in the paper, textile, waste water purification and food packaging industries.
"They activate the defensive processes of plants forming films on treated surfaces. They have an anti-microbial function against fungi, algae and bacteria," explained Marina Collina, researcher of the Agricultural Science Department at the University of Bologna. They are commonly used in post-harvesting to delay ripening and against the formation of bacteria.
"We know very little of how they work pre-harvesting, though. Chitosans have been classified as food supplements in 2011 and Chipro asked the EU to approve its hydrocloride chitosan, which is now recognised as a basic substance, whereas all the other chitosans are still considered fertilisers."
The public at the conference.
In Lazio, chitosans have been tested by the CRA against Psa with interesting results: "They worked basically all of the time, though less on flowers. They do not reduce grades and could be very useful," explained Marco Scortichini.
Kiwi mapping
Another important activity for the fight against the Psa is the creation of an Italian registry. "The aim is to map kiwis in Italy. We are using OP and Region data. We have already mapped 60% of the territory, with 5,503 companies registered, and we can already say that orchards are mostly old, 15 year old on average. Hayward is the most popular variety," said Trentini.
Luciano Trentini from CSO during his speech.
The kiwi registry is part of the Interact project financed by Mipaaf and coordinated by the CRA. The main objective is supply technical support and coordination to define a national strategy against the Psa.