The PPV virus (Plum Pox Virus), commonly known as Sharka, affects apricot, peach and plum trees causing a number of symptoms and, in the worst cases, also causes fruit drop. It can lead to significant losses - up to 80-100% - depending on the fruit and its susceptibility to the virus.
The Horticultural Faculty of Mendel University in Brno (Czech Republic) selected new promising varieties of stonefruit that seem to be resistant to the Sharka virus. The cultivars are currently being registered and have been obtained by introducing a number of Chinese varieties into the breeding programme.
French nursery gardens Pépinières Escande will launch the new varieties on the European market in cooperation with a few Italian partners.
At Interpoma 2014, FreshPlaza met with professor Boris Krska from the Fruit-growing Department of Mendel University to talk about the developments of stonefruit cultivation in his country. "Nowadays, the percentage of fruit marketed by retailers is on the rise, so growers are abandoning traditional varieties to choose cultivars that present the characteristics required by the market."
IProf. Boris Krska with Rossella Gigli. The professor is holding a leaflet presenting the apricot cultivars resistant to Sharka - Adriana; Betinka, Candela and Sophia.
On the other hand, though, the drastic reduction in the use of pesticides (to comply with current standards) and climate change are leading to an increase of diseases.
"The PPV virus is spreading with a stronger strain. Once, Sharka used to only affect plums, but now peaches are also afflicted. That is why breeding and the development of new varieties is vital."
In the Czech Republic, fruit is cultivated on 18,000 hectares, 9,000 of which are dedicated to apples and 4,000 to stonefruit. The main varieties of apples are Golden Delicious, Gala, Idared and Champion. Red delicious are not so popular any more but Braeburn are doing better. As regards stonefruit, in addition to plums, apricots and peaches, cherries and industry black cherries are also cultivated.
The preliminary tests carried out on apricots in Italy are currently limited by the fact that it is not cold enough.