The results of the LIFE - Susafruit project started in 2014 to develop integrated control strategies using fewer crop protection products, was presented on the same day.
The objective of the project is technological innovation for the improvement of quality, against adversity through monitoring and prevention against scab, for the monitoring of the main apple insects (Cydia pomonella andHaliomorpha halys) and for environmental sustainability using less pesticides and fungicides.
Venturia inaequalis on an apple (Photo by Davide Spadaro)
Professor Davide Spadaro from the University of Turin illustrated the most recent information regarding the biology and epodemiology of V. inaequalis and the development of specific diagnostic techniques to quickly detect the pathogen. Field detection can be carried out with sensors, as explained by Roberta Calmo from Politecnico di Torino while discussing the new technological applications and cantilevered nanobiosensors using molecular probes in particular.
During two years of sampling, pathologists obtained approximately 100 V. inaequalis isolates from the three cultivars being studied (Golden, Gala and Ambrosia) and Simona Prencipe from the University of Turin found evidence of the high genetic variability of Piedmont isolates. In vitro trials evidenced the existence of isolates with different degrees of resistance or sensitivity to fungicides that inhibit the synthesis of ergosterols and strobilurins.
Sometimes, pathogens that don't manifest in the field remain latent until they find the favourable conditions to manifest, which usually happens in packaging warehouses.
Marta Mari from the University of Bologna and Gianni Ceredi from Apofruit illustrated the results obtained on apples and peaches using thermotherapy as a post-harvesting treatment to contain rot. It's a completely natural system to contain latent post-harvesting pathogens. No authorisation is required and therefore it can be applied immediately for organic productions as well. Two prototypes for the hot water treatment of apples and peaches are currently being assessed in Emilia Romagna.
The meeting continued with Graziano Vittone from Agrion, who illustrated the defence techniques and strategies in Piedmont and means of scab prediction and containment. A distinction was made between preventive products to be applied before the rain, timely products to be used during germination and retroactive products to employ when the infection is already underway.
Vittone also provided a few recommendations on the use of specific products. Ergosterol synthesis inhibitors (I.B.E. - difenoconazole) must be used only when needed and always mixed in with a coverage product. They are effective at a temperature above 10% if applied to dry plants. If applied to wet plants, they can favour russeting. They must not be used in case of secondary infections.
Strobilurins (Flint and Bellis must not be used in case of ongoing secondary infections and there are numerous reports of resistance in areas where they have been used for years (France).
The same goes for Anilinopyrimidines (Scala, Chorus, Vision Plus), but they must be used on dry plants. This class of fungicides also works at relatively low temperatures (5°C) and must be used until blossoming.
The new SDHI products (Fontelis, Sercadis, Luna Experience) are at risk of resistance and must be used correctly. It's best to used them mixed in with another product (except for Luna, which is pre-mixed).
Finally, Lorenzo Berra from Agrion talked about the pros and cons of the new resistant apple varieties already available on the market and that will be introduced soon.