Abstract
A mutation is a sudden heritable change in the DNA in a living cell, not caused by genetic segregation or genetic recombination. Mutation breeding is the purposeful application of mutations in plant breeding. Unlike hybridization and selection, mutation breeding has the advantage of improving a defect in an otherwise elite cultivar, without losing its agronomic and quality characteristics. Mutation breeding is the only straightforward alternative for improving seedless crops. Since the first release of mutant cultivars that resulted from basic mutation research in Europe, mutation breeding has found a niche in plant breeding because of these advantages. Methodologies for mutation induction have been improved in main crops for both physical and chemical mutagens, and selection methodologies for mutant populations have been described. New mutagenic agents such as ion-beam radiation and cosmic rays are being investigated and a hitherto undescribed wide spectrum of mutations has been observed. Nevertheless, alkylating agents and ionizing radiation are still popular. The development of robust in vitro techniques for many crop species has contributed to improving the efficiency of mutation breeding. The ability to handle large mutagenized populations in a confined space, faster progeny turnover in vegetatively propagated species and the ability to screen for several biotic and abiotic stress factors in the culture environment make in vitro approaches very efficient. Mutant screening has undergone revolutionary changes in the past decade with reverse genetic approaches taking precedence. Therefore, integration of mutation techniques with molecular approaches is providing exciting opportunities for modern plant breeding.