TRANSGENIC RICE PLANTS HARBORING AN INTRODUCED POTATO PROTEINASE-INHIBITOR-II GENE ARE INSECT-RESISTANT

We introduced the potato proteinase inhibitor II (PINII) gene (pin2) i nto several Japonica rice varieties, and regenerated a large number of transgenic rice plants. Wound-inducible expression of the pin2 gene d riven by its own promoter, together with the first intron of the rice actin 1 gene (act1), resulted in high-level accumulation of the PINII protein in the transgenic plants. The introduced pin2 gene was stably inherited in the second, third, and fourth generations, as shown by mo lecular analyses. Based on data from the molecular analyses, several h omozygous transgenic lines were obtained. Bioassay for insect resistan ce with the fifth-generation transgenic rice plants showed that transg enic rice plants had increased resistance to a major rice insect pest, pink stem borer (Sesamia inferens). Thus, introduction of an insectic idal proteinase inhibitor gene into cereal plants can be used as a gen eral strategy for control of insect pests.