The Assessment of Natural Cross Pollination Properties of a Novel Male-Sterile-Female-Fertile Mutation in Soybean.

The value of a novel soybean male-sterile mutation in breeding practice was determined by its outcrossing properties. Then, the effects of different planting arrangements on the pod set characteristics of male-sterile plants were assessed by using orthogonal experiments at two sites. At the same time, the effects of male sterility on other traits were assessed in two CF populations. In addition, the nectar secretion and natural outcross of male-sterile plants from four lines were compared with one line and one line. The results of the orthogonal experiment showed that the pod numbers and pod set rates of male-sterile plants were decisively different between the two experimental sites but not between the two levels of the other factors. Both increasing the ratio of paternal parent to maternal parent and planting the parental seeds in a mixed way, the proportion of seeds pollinated by the target parent pollen could be increased. Except for the pod number per plant trait, there was no significant difference between male-sterile plants and their fertile siblings. The amount of nectar significantly differed among the lines. Compared with and male-sterile plants, the four lines possessed significantly more or similar numbers of pod sets. The results of this study lay a foundation for the future use of this mutant in soybean breeding.