1. State Key Laboratory for Agrobiotechnology and Key Laboratory of Crop Heterosis and Utilization (MOE), Beijing Key Laboratory of Crop Genetic Improvement, Department of Plant Genetics and Breeding, China Agricultural University, Beijing 100193, P.R. China
2. National Research Centre on Plant Biotechnology, New Delhi 110012, India
3. University of Massachusetts Amherst, Biochemistry and Molecular Biology, Amherst, Massachusetts 01003