As is well known, a gametophytic self-incompatibility system (GSI) determines fertility in sweet cherry varieties and prevents pollination with self and genetically related pollen. This mechanism is controlled by a multiallelic S locus that encodes two genes involved in fertilization: the allele-specific ribonuclease S (S RNase) expressed in the female style and the S-specific F-box protein (SFB) in the male pollen.
Figure 1. Graphical representation of incompatibility mechanisms in sweet cherry.
The knowledge of the S genotype of sweet cherries is very important for cherry growers. In fact, to achieve good pollination and fruit set, in addition to an adequate presence of pollinators and the correct choice of varieties with overlapping bloom, perfect genetic compatibility between the main variety and its pollinator must be ensured.
Over the years, molecular markers have been developed to distinguish S alleles in sweet cherries. In a recent update by Schuster and Schröpfer of the JKI - Julius Kühn-Institut (Germany), a total of 72 incompatibility groups in 1700 sweet cherry cultivars were listed.
Twenty-six sweet cherry cultivars have a unique combination of S alleles, have been described as universal donors, and were categorized into incompatibility group 0. Additionally, there are 91 sweet cherry genotypes that are self-compatible (SC) or self-fertile (SF) and belong to group SC.
So far, a total of 26 different S alleles have been described in cultivated sweet cherries (for further details: https://cherrytimes.it/news/una-panoramica-sugli-s-alleli-delle-ciliegie-dolci-coltivate).
Building on the work of the German research group, Jesús Alonso Sánchez, a researcher at the Spanish National Research Council (CSIC), has created a kind of easily searchable online database.
To access the file click here
Cherry Times editorial staff
Image source: SL Fruit Service; Primrose
15 Jan 2024
In 2010, a major development project, Consorcio Tecnológico de la Fruta, was initiated to obtain new cultivars suited to the Chilean climate and export market. 24 of the 30 advanced selections have already been grafted and are being studied.
24 Dec 2024
Developing a fruit-growing project in southern Chile is different from what happens in other production areas. Here, a warm humid temperate climate and volcanic soils dominate, which result in late production and risks of climatic events during critical phenological periods.
22 Aug 2025
Little Cherry Disease (LCD) is damaging cherry orchards across Washington State, with growers reporting severe losses. Tree removals and bitter, undersized fruit are symptoms of this threat—comparable to citrus greening (HLB) in Florida’s citrus industry.
22 Aug 2025
In Puglia, research on organic orchards highlights how compost and organic fertilizers boost yield, improve soil health, and enhance plant resilience. A sustainable approach that supports Mediterranean organic farming while delivering environmental and agronomic benefits.
