Rice (Oryza sativa L.) is one of the most important crops in the world. It is stimated that this specie reduces its maximum theoretical yield in a 50% per yeardue to plagues and deseases.

The objective has been to transffer, integrate and express the barley gene ItrI which encode the inhibitor of tripsine BTI-Cme, to differenciated cells (callus) of indica and japonica cultivars, as well as regenerate complete rice plants out of transformed cells.

Rice plants In vitro propagation systems have been established through the use of somatic embryogeneses, and gene transfference conditions optimiazed through particles bombing. ItrI gene carriers genic construction have been design as well as selective genes alowing only cells growth transformed in selective media.

Using rice DNA as a mold and nucleotides deduced from baley ItrI gene as a primer, a DNA of expected size has been amplified through PCR, however correspondent protein in non of the analysed non-transgenic rice tissues (seeds and leaves) hase been detected

The selected transformed plants have been molecularly and biochemicaly analized.

They have been obtained 12 rice transgenic plants, 7 from the indica type line IR58 and 5 from japonica type Senia cultivar, which carried the transgene and expressed the corresponding protein . Trypsine inhibition in vitro assays have proved the BTI-Cme protein to be highly functional in transgenic rices.Future bioassays with nsects will determine these plants´insecticide capability.

It has been internationaly published for 4 times and has been presented in the National Rice Congress, the 1st International Rice Meeting about genetic engineering.It has also defined a doctorate thesis.