MALE STERILITY IN SOYBEAN-AN OVERVIEW

The most common type of reproductive mutations observed in the soybean Glycine max (L.) Merr.] are those that induce male sterility. The high frequency of occurrence of male-sterile mutations indicates that a number of genes influence the processes of microgametogenesis and microsporogenesis. The current knowledge of these mutations is summarized. The origins of male-sterile mutations, their inheritance patterns, and known linkage relationships are detailed. The phenotypic expression of male-sterile mutations, including their effects on both male and female reproduction, is discussed. The influence of environment on the expressivity of male-sterile mutations, and the effects of male-sterile mutations on physiological processes (senescence and nitrogen fixation) are summarized. Male-sterile mutations have been useful in the study of soybean reproduction, genetic and cytogenetic investigations, and in evaluating the potential for commercial production of hybrid soybeans. These various applications of male-sterile mutations are presented.