The monograph summarizes the theoretical information on mutagenesis the use of this method in the breeding of agricultural plants and the results achieved. The results of the authors'' long-term research on the creation of initial breeding material based on chemical mutagenesis in the breeding of fruit and berry plants: black and red currants gooseberry felt-cherry and sweet cherry trees are presented. The monograph is addressed to researchers breeders graduate students undergraduates teachers and students of agricultural universities specialists of horticultural farms and amateur gardeners.