Wild and Rare Self-Incompatibility Allele S17 Found in 24 Sweet Cherry (Prunus avium L.) Cultivars

Abstract

The pollination of self-incompatible diploid sweet cherry is determined by the S-locus alleles. We resolved the S-alleles of 50 sweet cherry cultivars grown in Estonia and determined their incompatibility groups, which were previously unknown for most of the tested cultivars. We used consensus primers SI-19/20, SI-31/32, PaConsI, and PaConsII followed by allele-specific primers and sequencing to identify sweet cherry S-genotypes. Surprisingly, 48% (24/50) of the tested cultivars, including 17 Estonian cultivars, carry the rare S-allele S17, which had initially been described in wild sweet cherries in Belgium and Germany. The S17-allele in Estonian cultivars could originate from ‘Leningradskaya tchernaya’ (S6|S17), which has been extensively used in Estonian sweet cherry breeding. Four studied cultivars carrying S17 are partly self-compatible, whereas the other 20 cultivars with S17 have not been reported to be self-compatible. The recommended pollinator of seven self-incompatible sweet cherries is of the same S-genotype, including four with S17-allele, suggesting heritable reduced effectiveness of self-infertility. We classified the newly genotyped sweet cherry cultivars into 15 known incompatibility groups, and we proposed four new incompatibility groups, 64–67, for S-locus genotypes S3|S17, S4|S17, S5|S17, and S6|S17, respectively, which makes them excellent pollinators all across Europe. Alternatively, the frequency of S17 might be underestimated in Eastern European populations and some currently unidentified sweet cherry S-alleles might potentially be S17.

An Overview of S-Genotype Diversity in Sweet Cherry Landraces Grown in the Central Region of the Republic of Serbia

“…Eight S-alleles were found in Croatian landraces (S 1 to S 6 , S 9 and S 12 ;Ercisli et al, 2012), as well as in Czech and Ukrainian genotypes (S 1 to S 6 , S 9 and S 13 ;Lisek et al, 2015). Six S-alleles (S 3 to S 6 , S 13 and S 17 ) were identified in Estonian sweet cherry cultivars (Kivistik et al, 2022). The most striking difference in Estonian germplasm was the occurrence of the S 17 allele, which was found with a frequency of 53%.…”

“…In the latest update, the same author reported a total of 63 incompatibility groups (IGs) in 1,483 genotypes, then a group '0', described as universal donors, comprising 26 genotypes, and a group 'SC' consisting of 91 self-compatible sweet cherries. In addition, Kivistik et al (2022) proposed four new IGs (64 ‡67) for the S-genotypes S 3 S 17 , S 4 S 17 , S 5 S 17 and S 6 S 17 , detected in sweet cherry cultivars grown in Estonia. The cause of self-compatibility in sweet cherry is attributed to the artificial pollen-part mutation of SFB 3 ' and SFB 4 ' (Sonneveld et al, 2005), the natural pollen-part mutation of SFB 5 ' (Marchese et al, 2007), and the mutation of a non S-locus EMPaS02, which also leads to a loss of pollen function (Cachi & Wünsch, 2011).…”

“…Therefore, consensus/allele-specific polymerase chain reaction (PCR)based methods enabled the use of the S-locus as a genetic marker for genotyping and identification of domestic (released cultivars and landraces) and foreign sweet cherry cultivars at the Fruit Research Institute, ^a~ak (FRI) (Mari} & Radi~evi}, 2014;Radi~evi} et al, 2015;Mari} et al, 2017Mari} et al, , 2019Mari} et al, , 2021. The polymorphism of the S-locus has also been used for assessment of local sweet cherry germplasms in different countries of Europe and North and West Asia, where a high genetic diversity among landraces was found (Ipek et al, 2011;Ercisli et al, 2012;Cachi & Wünsch, 2014a;Lisek et al, 2015;Marchese et al, 2017;Schuster, 2020;Kivistik et al 2022). In addition, the Italian sweet cherry landrace 'Kronio' and the Spanish 'Cristobalina' and 'Talegal Ahin' have so far been identified as sources of self-compatibility (Marchese et al, 2007;Cachi & Wünsch, 2014b).…”

Molecular insights into self-incompatibility systems: From evolution to breeding

“…Allele-specific polymerase chain reaction is routinely used to identify S -genotypes and new S -alleles in important fruit crops, including apple ( M . domestica ) ( Sheick et al., 2018 ), apricot ( Prunus armeniaca ) ( Orlando Marchesano et al., 2022 ), cherry ( Prunus avium ) ( Kivistik et al., 2022 ), almond ( Prunus dulcis ) ( Gouta et al., 2021 ), plum (diploid Pyrus salicina , hexaploid Pyrus domestica and Pyrus insititia ) ( Abdallah et al., 2019 ), and pear ( Pyrus communis ) ( Claessen et al., 2022 ). These S -genotypes have been particularly useful in commercial orchard management, making it possible to rapidly determine compatible combinations among cultivars and shorten the generation cycle needed to characterize a genotype ( Dirlewanger et al., 2004 ).…”

Joint metabolome and transcriptome analysis of the effects of exogenous GA3 on endogenous hormones in sweet cherry and mining of potential regulatory genes

“…Versatile and economical, sweet cherries are among the most popular fruits and are widely cultivated worldwide. However, sweet cherriy is a typical self-incompatible species controlled by the multi-allele expressed by a single gametophyte ( Kivistik et al., 2022 ), and artificial pollination is often used to improve the fruit set. The workload of manual pollination is large and consumes considerable manpower and material resources.…”