Early Mutants Induced by RadiatiorLs and Chemicals in Barley I. Frequencies of Early Mutations and Brief Description of the Selected Mutants.

Abstract

Since 1963, a number of mutagenic treatments were carried out to find effective methods for induction of useful mutations in a six-rowed winter barley cultivar "Chikurln lbaraki 1". The mutagens applied were T-rays, thermal neutrons and chemicals, i.e. ethylene imine (EI), ethyl methanesulfonate (EMS) and N-nitroso-N-methylurea (NMU). During the course of the study, a total of 61 early maturity mutants have been isolated. The present paper shows the frequency of early mutation for various mutagens and physio 10gical and genetic natures of the early mutants selected. Efficiency for inducing early mutation was compared among the mutagens used.