The Organizing Committee welcomes you to the IV International Symposium on Citrus Biotechnology (ISCB) held in Uruguay from April 16th to 18th, 2018. This Symposium is organized by International Society for Horticultural Science (ISHS), International Society of Citriculture (ISC) and the National Agricultural Research Institute (INIA) of Uruguay. The ISCB has been organized by the ISHS since 1998. The first ISCB took place in Eilat, Israel by the efforts of PhD. R. Goren, PhD. E. E. Goldschmidt, PhD. M. Davidzon and PhD. Y. Erner. The second International Symposium was held in Catania, Italy in 2009 organized by of PhD. A. Gentile and PhD. E. Tribulato. The third Symposium was held in Shizuoka, Japan in 2014 by PhD. Shimizu and PhD. Tominaga. The IV ISCB aims to gather knowledge in a wide range of fields where Biotechnology is applied in order to improve the Citrus Industry worldwide. The applications and approaches based on biotechnology are widely used in all research fields for greatly reducing time span and improving reliability in citrus studies for breeding, genomics and genetics, physiology and fruit quality, pests and diseases management and the advance and application of new emerging technologies. Therefore, we are confident that this ISCB will greatly contribute to strengthen the development of your research as well as the Citrus Industry.