Abstract
Male-sterile plants, producing nonviable pollen, were recovered from a Venezuelan seed stock of sesame ( Sesamum indicum L.). Grosses between these plants and male-fertile cultivars produced a proportion of F 2 segregants that were also male-sterile. Seed set on male-sterile plants following hand pollinations with normal pollen was high indicating that these plants were female-fertile. Greenish anther color at pollen dehiscence distinguished male-sterile from male-fertile plants, the latter having whitish anthers. Microscopic examinations revealed that sterile anthers had no endothecium and that their pollen lacked exine and had no definite wall surface structure. Observations on flower morphology of F 2 plants indicated that the male-sterility trait is stable, easily maintained under greenhouse and open field conditions and positively recognizable 3 to 4 days before anthesis. The male-sterility described here can be used for commercial hybrid seed production which could lead to major increases of sesame yield per hectare.
Key Words: Pollen • Microsporogenesis • Exine • Endothecium
1 Contribution from the Dep. of Botany and Plant Sciences, Univ. of California, Riverside, CA 92521. This work was partially supported by a grant from the UNDP.
2 Plant breeder, Kenana Research Station, AbuNaama Sudan, and professor of agronomy, Univ. of California, Riverside, respectively.
Received for publication February 9, 1981.