Efficient production of male and female sterile plants by expression of a chimeric repressor in Arabidopsis and rice.

Male and female sterile plants are particularly useful for the effective production of commercial hybrid plants and for preventing the diffusion of seeds or pollen grains of genetically modified plants in the open field. In an attempt to create several types of sterile plant by genetic manipulation, we applied our Chimeric REpressor Gene-Silencing Technology (CRES-T) to four transcription factors, namely APETALA3, AGAMOUS, LEAFY and AtMYB26, involved in the regulation of petal and stamen identity, stamen and carpel identity, floral meristem identity and anther dehiscence, respectively, in Arabidopsis. Transgenic plants expressing each chimeric repressor exhibited, at high frequency, a sterile phenotype that resembled the loss-of-function phenotype of each corresponding gene. Furthermore, in the monocotyledonous crop plant 'rice', expression of the chimeric repressor derived from SUPERWOMAN1, the rice orthologue of APETALA3, resulted in the male sterile phenotype with high efficiency. Our results indicate that CRES-T provides a powerful tool for controlling the fertility of both monocots and dicots by exploiting transcription factors that are strongly conserved amongst plants.