Mitotic crossing-over in a higher plant

Abstract

SUMMARY This paper provides direct evidence for the occurrence of mitotic crossing-over in leaf tissues and in vitro cell cultures of Nicotiana tabacum . The geno-typic composition of both segregating regions of twin spots was analysed by in vitro culture of the segregating tissue and by regenerating plants from this tissue. The frequency of mitotic crossing-over is influenced by several physical and chemical agents.