If the gene effect was dominant, then any male with the sterility allele would not be able to reproduce. This would mean that the allele would most likely be removed from the population by genetic drift within a relatively small number of generations.
The exception would be if the male sterility allele, or another linked locus on the genome, conferred such a strong fitness effect on women who carried the allele that it approximately doubled their fecundity, in which case there would be neutral selective pressure overall and the dominant allele would survive in the population for much longer.
So, to summarise my thought, male sterility tends to be a recessive trait because if it were a dominant trait, there would be very strong selective pressure to remove the trait from the population.
Naturally, sexually reproductive ling organisms can mate and produce offsprings. In general, they are both male- and female fertile. However, male sterility (and female sterility also; e.g. barrenness) result from gene mutation or chromosomal aberration of some sort. These genetic "accidents" occur sparingly and at random. Specifically, most mutations produce mutant genes that do not survive in the population. The relatively few that survive are recessive. Since mutants are deleterious, they are quickly eliminated from the population if they are dominant. In the recessive state, they remain in the population from generation to generation because they are not easily detected. If they now occur in the homozygous recessive state, they become visible and selection against them becomes possible. It should be noted, however, that male sterility has been used to advantage in producing hybrid varieties of some crops such as sorghum.
Fine mapping and cloning the male sterile genes under different environments are underway. Further improve understanding of the genetic mechanism of the male sterile system is needed to be evaluated.
I agree with Fakorede & Moore. Loss of function by mutation called recessive mutation. Here male or female sterility is loss of function in normal functional gene (s). In natural populations these kind of mutations get purged off in subsequent generations. But in crops, artificial selection applied to fix this mutation in population for hybrid breeding so mostly they are recessive in nature..
Cotton also has a dominant male sterility gene (MS4). Allison, D.C., and W.D. Fisher. 1964. A dominant gen for male sterility in Upland cotton. Crop Sci. 4:458-459
Male sterility is governed by both recessive and dominant gene(s)/alleles, but the male sterility governed by dominant gene(s) is not useful for hybrid seed production. Male sterility governed by recessive alleles is being used in many crops for hybrid seed production.
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