A CHIMERIC RIBONUCLEASE-INHIBITOR GENE RESTORES FERTILITY TO MALE STERILE PLANTS

Male fertility was restored to genetically engineered male sterile oilseed rape plants. Male sterile plants that express a chimaeric ribonuclease gene in the anther tapetal cell layer were crossed with male fertile plants that were transformed with a chimaeric tapetal-cell-specific ribonuclease-inhibitor gene. F1 progeny expressing both genes are restored to male fertility by the suppression of cytotoxic ribonuclease activity in the anther by the formation of cell-specific RNase/RNase inhibitor complexes. Genetically engineered male sterility and fertility restorer genes should facilitate hybrid seed production in crop plants.