Controlling for genetic identity of varieties, pollen contamination and stigma receptivity is essential to characterize the self-incompatibility system of Olea europaea L.

Pierre Saumitou-Laprade (1) , Philippe Vernet (1) , Xavier Vekemans (1) , Vincent Castric (1) , Gianni Barcaccia (2) , Bouchaib Khadari (3) , Luciana Baldoni (4)

1 Evo-Eco-Paléo (EEP) - Évolution, Écologie et Paléontologie (Evo-Eco-Paleo) - UMR 8198
2 Dipartimento di Agronomia Animali Alimenti Risorse Naturali e Ambiente
3 UMR AGAP - Amélioration génétique et adaptation des plantes méditerranéennes et tropicales
4 Institute of Biosciences and Bioresources

Bervillé et al. express concern about the existence of the diallelic self-incompatibility (DSI) system in Olea europaea, mainly because our model does not account for results from previous studies from their group that claimed to have documented asymmetry of the incompatibility response in reciprocal crosses. In this answer to their comment, we present original results based on reciprocal stigma tests that contradict conclusions from these studies. We show that, in our hands, not a single case of asymmetry was confirmed, endorsing that symmetry of incompatibility reactions seems to be the rule in Olive. We discuss three important aspects that were not taken into account in the studies cited in their comments and that can explain the discrepancy: (i) the vast uncertainty around the actual genetic identity of vernacular varieties, (ii) the risk of massive contamination associated with the pollination protocols that they used and (iii) the importance of checking for stigma receptivity in controlled crosses. These studies were thus poorly genetically controlled, and we stand by our original conclusion that Olive tree exhibits DSI.

Mots clés: Diallelic self-incompatibility system; Oleaceae; Paternity analysis; Plant mating systems; Symmetry in reciprocal crosses

Mots clés: Olea europaea L

Domaines: Génétique des plantes

Pierre Saumitou-Laprade, Philippe Vernet, Xavier Vekemans, Vincent Castric, Gianni Barcaccia, et al.. Controlling for genetic identity of varieties, pollen contamination and stigma receptivity is essential to characterize the self-incompatibility system of Olea europaea L.. Evolutionary Applications, 2017, 10 (9), pp.860-866. ⟨10.1111/eva.12498⟩. ⟨hal-01597853⟩