Induction of Mutations by Ethyl Methanesulphonate Treatment of Monosomics of Common Wheat, Triticum aestivum L.

Abstract

Aiming to screen mutant genes on nine chromosomes of homoeologous groups, I, V and VII in common wheat (Triticum aestivum L.), selfed seeds of their monosomics and a normal disomic line of cv. Chinese Spring were treated with 0.3 and 0.4% ethyl methanesulphonate(EMS). Higher survival was observed in mono-1A, 1B and 1D than in other monosomics and the normal line in the M1 generation, indicating some increase of tolerance to EMS by the hemizygous state of either the 1A, 1B, or 1D chromosome. A few M2 Iines were bred true for weak chlorosis and necrosis(mono-1A, 1B, 1D, 5A, 5B, 7A, 7D), seedling lethality (mon0-1B, 1D), striped leaf color (mono-1B), dwarfing (mono-1A, 1B, 1D, 5D), or for compactoid (mono-5A) and sphaerococcoid characters (mono-7B, 7D). According to the scheme shown in Fig.1, most of these mutations were assumed to have occurred on a chromosome that was monosomic in the M1 generation. Unique consequences of the mutagen treatment of monosomics, compared to that of disomics, in the M1 and M2 generations are pointed out.