A new method called ‘speed breeding’ greatly shortens generation time and accelerates breeding and research programmes.
The new breeding platform developed by teams at the John Innes Centre, University of Queensland and University of Sydney, uses a glasshouse or an artificial environment with enhanced lighting to create intense day-long regimes to speed up the search for better performing crops. Using the technique, the team has achieved wheat generation from seed to seed in just 8 weeks. These results appear in Nature Plants.
This means that it is now possible to grow as many as 6 generations of wheat every year – a threefold increase on the shuttle-breeding techniques currently used by breeders and researchers.
Dr Brande Wulff of the John Innes Centre, Norwich, a lead author on the paper, explains why speed is of the essence:
“Globally, we face a huge challenge in breeding higher yielding and more resilient crops. Being able to cycle through more generations in less time will allow us to more rapidly create and test genetic combinations, looking for the best combinations for different environments.”
This technique uses fully controlled growth environments and can also be scaled up to work in a standard glass house. It uses LED lights optimised to aid photosynthesis in intensive regimes of up to 22 hours per day. LED lights significantly reduce the cost compared to sodium vapour lamps which have long been in widespread use but are ineffective because they generate much heat and emit poor quality light.
The international team also prove that the speed breeding technique can be used for a range of important crops. They have achieved up to 6 generations per year for bread wheat, durum wheat, barley, pea, and chickpea; and four generations for canola (a form of rapeseed) instead of 2–3 under normal glasshouse conditions. This is a significant increase compared with widely used commercial breeding techniques.
Speed breeding, when employed alongside conventional field-based techniques, can be an important tool to enable advances in understanding the genetics of crops. The study shows that traits such as plant pathogen interactions, plant shape and structure, and flowering time can be studied in detail and repeated using the technology.
The researchers 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.
Watson et al. Speed breeding is a powerful tool to accelerate crop research and breeding, Nature Plants (2018).doi:10.1038/s41477-017-0083-8