Old apple varieties will help in the future

03/25/2022 - (Source © lid.ch) - Old fruit varieties are important for future breeding. The Swiss Apple Core Collection serves to preserve and research old apple varieties - as capital for the future.

By Jonas Ingold

There are usually only a few well-known apple varieties on store shelves. In Switzerland, however, there are well over 1000 different varieties. And the old, mostly forgotten varieties in particular are much more than just nostalgia. With their genetic diversity, they ensure the breeding of the future, which must be adapted to climate change, pests, diseases and other external influences.

Preserve and use old varieties

The preservation and description of such old varieties is therefore important. Without preservation, the genetic resources are lost forever, without a description it is not known how and whether the old varieties can be used. For this reason, the apple core collection was started in Switzerland. It's not about apple seeds, but about a core collection.

Selected apple varieties are grown at three different climatic locations in Switzerland for a period of 6 years. The apples are examined for their properties. What are the characteristics of the fruit? Are they resistant or tolerant to plant diseases? Such questions should provide information on how the old varieties can be used.

Breeding apple varieties is time-consuming. Apples are self-sterile, ie they cannot fertilize themselves, but need the pollen of a foreign variety. If you plant the cores of the resulting apple, it no longer has the same properties as the original variety. In order to preserve and propagate a variety, it must therefore be grafted (grafted). The resulting trees are clones. It takes several years for a new variety to bear fruit.

3000 became 1300

To create the Core Collection, 3125 apple varieties were collected in Switzerland. Using molecular markers, it was determined that a large number of these are duplicates, according to the Swiss Journal for Obst- und Weinbau . So these are the same varieties known by different names. A good 1300 varieties remained, which were divided into 330 groups by means of relationship analyses. One cultivar was selected from each group for core collection. Together with selected reference varieties, the collection now comprises 358 varieties.

In order to examine the varieties under different climatic conditions, they are spread over three locations. In Grabs SG, the Vetsch family of fruit growers is responsible for the collection, in Conthey VS Agroscope and the canton of Valais, and in Wädenswil the ZHAW. In Wädenswil, the apples are farmed organically. The varieties were planted in Wädenswil and Grabs in 2019 and in Conthey in 2020.

More efficient breeding hoped for

In a first phase, the supervisors examine the varieties for their fruit and tree characteristics (phenotypic characteristics). In a second phase, it is considered how resistant and tolerant the varieties are to pests and diseases. In the sixth and last year of the project, high-resolution genetic profiles of all planted varieties will be created. According to SZOW, these profiles allow finding molecular markers that are inherited along with desired traits. This should increase the efficiency of selection in apple breeding and make new varieties available as quickly as possible.

The description project is financed by the Federal Office for Agriculture (FOAG) and is based at the Chair of Molecular Plant Breeding at ETH Zurich.

Find apples from local production on agroswiss.ch

Here you will also find old varieties of apples and pears: Find apples from our dealers here