1. Crop and Environmental Sciences Division; International Rice Research Institute; DAPO Box 7777 Metro Manila The Philippines
2. Plant Breeding Genetics and Biotechnology Division; International Rice Research Institute; DAPO Box 7777 Metro Manila The Philippines
3. Plant Breeding Laboratory; Faculty of Agriculture; Graduate School; Kyushu University; Fukuoka 812-8581 Japan
4. Crop Protection Cluster; University of the Philippines; Los Baños Laguna The Philippines