Accepted Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1111/plb.12656 This article is protected by copyright. All rights reserved. DR. GAETANO DISTEFANO (Orcid ID : 0000-0002-6080-6466) Article type : Research Paper Handling Editor: R.Bekker Temperatures during flower-bud development affect pollen germination, self-incompatibility reaction and early fruit development of clementine (Citrus clementina Hort. ex Tan.) Gaetano Distefano 1,* , Alessandra Gentile 1 , Afif Hedhly 2 , Stefano La Malfa 1 1 Dipartimento di Agricoltura, Alimentazione e Ambiente, University of Catania, 95123 Catania, Italy 2 Department of Plant and Microbial Biology and Zurich-Basel Plant Science Center, University of Zurich, CH-8008 Zurich, Switzerland *Corresponding author. Tel.: +39 095 234403; fax: +39 095 234406. E-mail address: distefag@unict.it ABSTRACT  One of the key environmental factors affecting plant reproductive systems is temperature. Characterising these effects is especially relevant for some commercially important genera such as Citrus. In this genus, failure of fertilisation results in parthenocarpic fruit