The growing human population and a changing environment have raised significant concern for global food security, with the current improvement rate of several important crops inadequate to meet future demand1. This slow improvement rate is attributed partly to the long generation times of crop plants. Here, we present a method called ‘speed breeding’, which greatly shortens generation time and accelerates breeding and research programmes. Speed breeding can be used to achieve up to 6 generations per year for spring wheat (Triticum aestivum), durum wheat (T. durum), barley (Hordeum vulgare), chickpea (Cicer arietinum) and pea (Pisum sativum), and 4 generations for canola (Brassica napus), instead of 2–3 under normal glasshouse conditions. We demonstrate that speed breeding in fully enclosed, controlled-environment growth chambers can accelerate plant development for research purposes, including phenotyping of adult plant traits, mutant studies and transformation. The use of supplemental lighting in a glasshouse environment allows rapid generation cycling through single seed descent (SSD) and potential for adaptation to larger-scale crop improvement programs. Cost saving through light-emitting diode (LED) supplemental lighting is also outlined. We envisage great potential for integrating speed breeding with other modern crop breeding technologies, including high-throughput genotyping, genome editing and genomic selection, accelerating the rate of crop improvement.
The authors wish to acknowledge the support of the Biotechnology and Biological Sciences Research Council, UK, the Two Blades Foundation, USA, the Department for Environment, Food and Rural Affairs, UK, and the International Wheat Yield Partnership, grant number IWYP76. S.G. was supported by a Monsanto Beachell-Borlaug International Scholarship. A.W. was supported by an Australian Post-Graduate Award and the Grains Research and Development Corporation (GRDC) Industry Top-Up Scholarship, project code GRS11008. The PBI facilities used in this project were funded with assistance from GRDC, project code US00053. H.R. also received funding by GRDC, project code DAN00208. J.B., D.E. and H.R. received funding from the Australian Research Council (ARC), project codes LP130100925 (J.B., D.E. and H.R.) and LP130100061 (D.E. and J.B.). M.A.M.H. was supported by a fellowship from Universiti Putra Malaysia, Malaysia. The authors also give thanks to the ARC for an Early Career Discovery Research Award, project code DE170101296, to L.T.H. We are grateful to the JIC, UQ and PBI horticultural staff for plant husbandry, M. Qiu (WWAI) for pod anatomy photography, A. Davis (JIC) for photography and J. Brown (JIC) for helpful discussions.
Supplementary Discussion, Supplementary Figures 1–14, Supplementary Tables 1–41, Supplementary References
Timelapse video recording comparing plant growth under speed breeding condition I and glasshouse conditions in United Kingdom summertime without any supplementary light. Video depicts three replicates of Triticum aestivum cv. Paragon sown and recorded under each treatment, with two replicates removed after stem extension stage was reached in each condition. Recordings were made using the CropQuant workstation developed by Ji Zhou and colleagues at the John Innes Centre [Supplementary Reference 4]. Germinated seedlings of Paragon were sown on 17 March 2017. Growth curves are illustrated in Supplementary Fig. 10.