Mutation breeding of grain legumes

Abstract

Grain legumes are an important group of crop plants. They provide an essential source of protein food for many developing countries, but their production has gone down in favour of more profitable crops like cereals. Therefore, genetic improvement of grain legumes is urgently needed. The primary aim of grain legume breeding must be the increase of production through adaptation to more advanced cropping schemes and reduction of crop losses. Symbiotic nitrogen fixation as developed by natural evolution does not always seem to be compatible with the needed substantial increase in yield: It is not supplying sufficient nitrogen and supplementation by fertilizer is rather uneconomic. By genetic manipulation of the plant's regulatory system nitrogen fixation may become more effective and tolerant to high soil nitrogen levels. Through a number of mutation breeding projects in different countries involving all important grain legume species it has been proven that mutation induction is a good tool for supplementing the genetic variation available from natural evolution and from selection by man. High-yielding cultivars have been developed from induced mutants, which eventually also possess a more efficient nitrogen fixation capacity. © 1984 Martinus Nijhoff/Dr W. Junk Publishers.