1. College of Water Resources and Civil Engineering China Agricultural University Qinghua East Road 17 100083 Beijing China
2. Department of Plants and Crops, Faculty of Bioscience Engineering Ghent University Coupure Links 653 9000 Ghent Belgium
3. Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering Ghent University Coupure Links 653 9000 Ghent Belgium