1. Department of Biological Sciences Royal Holloway University of London Egham TW20 0EX UK
2. Tozer Seeds Tozer Seeds Ltd Cobham KT11 3EH UK
3. Laboratory of Growth Regulators Institute of Experimental Botany Czech Academy of Sciences and Faculty of Science Palacký University Olomouc Olomouc CZ‐78371 Czech Republic
4. Swiss Light Source Paul Scherrer Institute Villigen CH‐5232 Switzerland