and the results were confirmedby in

and the results were confirmed
by inoculating rice germplasm with an M. grisea strain containing
AVR-Pita. The Pi-ta gene was found in accessions from several major
rice producing countries, including China, Colombia, Japan, Vietnam,
the Philippines, Iran and the United States. The usefulness of DNA
markers for rapid determination of the genotype of rice germplasm
was thus demonstrated. The Pi-ta gene also was found in rice cultivar
known to contain the Pi-ta2 gene, although the allelic relationship of
these genes remains to be determined. The presence of the Pi-ta gene in
landrace cultivars in several different geographical locations, the
Philippines and Vietnam, other indica rice cultivars in China and
Colombia suggest that the Pi-ta gene may have spontaneously
originated in indica rice cultivars. These results are useful for
incorporating the Pi-ta gene into advanced breeding lines by markerassisted
selection for rice breeding programmes worldwide.