Journal of Citrus Pathology

Argentina is the largest lemon producing country in the world and Tucumán province leads in lemon production. Knowing that disease free citrus propagating materials prevent the spread of diseases and are the basis of a profitable industry, the Estación Experimental Agroindustrial Obispo Colombres of Tucumán (EEAOC) established the Citrus Sanitation Center (CSC) in 2004. The goal of the CSC is to provide the important citrus varieties and rootstocks true to type and free of graft-transmissible pathogens as primary sources of propagating material for citrus growers and researchers in northwest Argentina. A national citrus certification program became mandatory in 2010 and enclosure of all commercial nurseries in January 2011.  At present, most of the main citrus varieties and rootstocks of commercial interest have been recovered through the standard procedure of shoot-tip grafting in vitro. Mother trees and increase blocks are maintained in insect proof greenhouses to supply budwood for rapid nursery multiplication. Regular testing of mother trees by biological, serological and molecular methods is performed for different virus, viroids, CVC, citrus canker and now HLB. Current surveys report that Tucuman is free of the vector, Diaphorina citri, and the HLB pathogen. The CSC will also perform HLB testing during quarantine entry of imported varieties to provide a program for safe accession of citrus germplasm and provision of clean budwood.