Selection of sugarcane plants resistant to SCMV

Abstract Sugarcane ( Saccharum spp.) is susceptible to several major diseases transmitted by insects such as Sugarcane Mosaic Virus (SCMV). In very susceptible plants, SCMV causes severe dwarfing, leaf and stem necrosis and serious production losses. We obtained sugarcane clones resistant to SCMV using induction mutation by irradiating. Calli from the susceptible cultivar B6749 with 2 krads of gamma rays. The regenerated plantlets were tested for resistance to strain B of SCMV in the greenhouse and the resistant clones were transferred to the field. They have shown stable resistance to viral infection for eight generations of asexual reproduction. To detect genetic changes related to the acquired resistance, 15 resistant clones and a clone from the original cultivar B6749 were analyzed using Random Amplified Polymorphic DNAs (RAPD). The RAPD patterns obtained with the primer OPM-14 detected a 854 bp fragment in the 15 resistant clones, which was not present in cultivar B6749. The study of genetic relations between the genotypes resistant to SCMV and its maternal B6749, using all RAPD primers, defined the existence of an associated polymorphic pattern to the resistance to SCMV. Existence of specific patterns for each genotype in the study was also observed. Analysis using RAPDs efficiently differentiated sugarcane clones resistant to SCMV by their genetic changes due to induced mutation.