ABSTRACT
Plant cell and tissue culture techniques have been developed and advanced for most of the commercially-important fruits, which provides a number of additional opportunities to conventional plant breeding, including an effective use of mutation induction protocols. Fruit crops are in general vegetatively propagated, since many of them are either self incompatible and/or complex polyploids. Mutation breeding is advisable either when the desired traits cannot be found in the existing germplasm or they cannot be transferred to a species or cultivar of interest. Mutagenesis, offering the possibility of altering only one or a few characters, has already been used to introduce useful traits (Briggs and
For Correspondence: E-mail: S.Predieri@ibimet.cnr.it
Constanin, 1977) and shows a potential for improving many fruit species. For some crops, induced mutation is the most suitable breeding technique. In dessert banana, conventional breeding failed to produce new cultivars because of no or extremely reduced seed production, while in vitro gamma-ray irradiation proved to be an effective tool (Novak et al., 1990; Tan et al., 1993; Bhagwat and Duncan 1998; IAEA 1998; Mak et al., 1998). Traits induced by mutagenesis include plant size, blooming time and fruit ripening, fruit color, self-compatibility, self-thinning, and resistance to pathogens (Visser et al., 1971; Janick and Moore 1975; Donini 1982; Lapins 1983; Spiegel-Roy 1990; Brunner and Keppl 1991; Janick and Moore 1996; van Harten 1998; Sanada and Amano 1998; Hartman and Vuylsteke, 1999; Predieri 2001). The number of cultivars successfully obtained through mutagenesis increases every year, by the end of 2001, it consisted of more than 2200, including about 50 cultivars of fruits belonging to more than 20 different species (FAO/IAEA Mutant Varieties Database; <https://www-infocris.iaea.org/MVD/>; October 2001).
