1. Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun Jilin 130102
2. Univ. of Chinese Academy of Sciences Beijing 100049 China
3. Da’an Sodic Land Experiment Station Da’an Jilin 131317 China
4. Jilin Agricultural Univ. Changchun Jilin 130118 China
5. Plant Disease Resistant Crop Research and Development Unit National Institute of Agrobiological Sciences Kannondai 2‐1‐2 Tsukuba 305‐8602 Japan