Inheritance and Characterization of the Fruit Ripening Mutation in ‘Alcobaca’ Tomato

A single recessive gene was found to be responsible for the abnormal fruit ripening of ‘Alcobaca’ tomato ( Lycopersicon esculentum Mill.). This gene causes a ripening syndrome characterized by attenuated respiratory activity and ethylene production, delayed softening of the fruit, low polygalacturonase (PG) activity, and extended shelf life. Allelism tests showed that the mutant gene of ‘Alcobaca’ is allelic to nor . It is proposed that the symbol nor A be used to refer to this mutant. The nor A allele is dominant to the nor allele.