Speed breeding is a powerful tool to accelerate crop research and breeding

Abstract

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 demand . 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.

Accelerated ex situ breeding of GBSS - and PTST1 -edited cassava for modified starch

“…The ability to efficiently modify genes in highly heterozygous crops, combined with accelerated time to flowering ( 46 ) to generate transgene-free progeny with a homozygous trait, should save several years over conventional breeding approaches and phenotypic recurrent selection (Fig. 6).…”

Identification of phytic acid mutants in oilseed rape (Brassica napus) by large‐scale screening of mutant populations through amplicon sequencing

“…Given that the experiments were conducted under controlled conditions, evaluation of the mutant's field trials will be an essential task for the future. Furthermore, the high mutation load of EMS mutants prevents their direct use in breeding due to the sometimes observed low vigor and poor yielding capacities, and therefore we initiated a program for a fast elimination of background mutations by backcrossing with distantly related early flowering spring‐type parents under speed breeding conditions (Watson et al , ).…”

A reductionist approach to dissecting grain weight and yield in wheat

“…To date many of the interactions between individual genes have been conducted using near‐isogenic lines which differ for the specific genes being studied (Gao et al ). This requires multiple rounds of backcrossing to combine the traits, which, despite accelerated growth conditions (Watson et al ), is cumbersome and time consuming. In the future, understanding the relationship between multiple genes affecting yield components will most likely require multiplex genome editing of the different targets across several genetic backgrounds (Shen et al ).…”