1. Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1878, USA
2. Department of Botany and Microbiology, Faculty of Science, Zagazig University, Zagazig 44519, Egypt
3. National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China