National Key Laboratory of Plant Molecular Genetics;
Institute of Plant Physiology and Ecology;
Shanghai Institutes for Bio- logical Sciences;
Graduate School of the Chinese Academy of Sciences;
Chinese Academy of Sciences;
Shanghai 200032;
China;
China National Rice Research Institute;
Chinese Academy of Agricultural Sciences;
Hangzhou 310006;
China;
Present address: Plant Biotechnology Institute;
National Research Council of Canada;
110 Gymnasium Place;
Saskatoon;
SK S7N 0W9;
Canada;