Acceleration of wheat breeding: enhancing efficiency and practical application of the speed breeding system

Abstract

Background Crop breeding should be accelerated to address global warming and climate change. Wheat (Triticum aestivum L.) is a major food crop. Speed breeding (SB) and speed vernalization (SV) techniques for spring and winter wheat have recently been established. However, there are few practical examples of these strategies being used economically and efficiently in breeding programs. We aimed to establish and evaluate the performance of a breeder-friendly and energy-saving generation acceleration system by modifying the SV + SB system. Results In this study, a four-generation advancement system for wheat (regardless of its growth habits) was established and evaluated using an energy-efficient extended photoperiod treatment. A glasshouse with a 22-hour photoperiod that used 10 h of natural sunlight and 12 h of LED lights, and minimized temperature control during the winter season, was successful in accelerating generation. Even with one or two field tests, modified speed breeding (mSB) combined with a speed vernalization system (SV + mSB) reduced breeding time by more than half compared to traditional field-based methods. When compared to the existing SV + SB system, the SV + mSB system reduced energy use by 80% to maintain a 22-hour photoperiod. Significant correlations were found between the SV + mSB and field conditions in the number of days to heading (DTH) and culm length (CL). Genetic resources, recombinant inbred lines, and breeding materials that exhibited shorter DTH and CL values under SV + mSB conditions showed the same pattern in the field. Conclusions The results of our SV + mSB model, as well as its practical application in wheat breeding programs, are expected to help breeders worldwide incorporate generation acceleration systems into their conventional breeding programs.

Synergizing breeding strategies via combining speed breeding, phenotypic selection, and marker-assisted backcrossing for the introgression of Glu-B1i in wheat

“…An initial artificial cross between Jokyoung and Garnet was conducted under field conditions. Two rounds of backcrossing with Jokyoung were performed under modified speed breeding combined with speed vernalization (SV+mSB), as described by Cha et al ( Cha et al., 2023b ). The BC 2 F 2 population was evaluated under mSB conditions, which enabled visual phenotypic selection based on the difference in days to heading (DTH) between the two parental lines.…”

“…The speed vernalization (SV) system, with a higher vernalization temperature of 8–10°C and a 22-h photoperiod, has facilitated up to five generations for both spring and winter wheat ( Cha et al., 2022b ). Subsequently, a modified speed breeding system (mSB), combined with SV, was confirmed to be suitable for practical use in large breeding populations ( Cha et al., 2023b ). The mSB system reduces the energy input by 80% and maximizes space utilization by harnessing natural sunlight in conventional glasses instead of relying solely on artificial lights.…”

“…The mSB system reduces the energy input by 80% and maximizes space utilization by harnessing natural sunlight in conventional glasses instead of relying solely on artificial lights. PS for agronomic traits and multiple disease resistance can also be effectively conducted while accelerating generations under SB or mSB conditions ( Hickey et al., 2012 ; Dinglasan et al., 2016 ; Riaz et al., 2016 ; Cha et al., 2023b ). These series of SB systems are believed to accelerate the development of breeding materials, as well as the overall wheat research by facilitating the creation of mapping populations.…”

Tools and Techniques to Accelerate Crop Breeding

“…This has been successively achieved in wheat, barley, chickpea, pea, canola [ 26 , 27 ], and a few orphan crops [ 28 ]. For example, a speed breeding system employing an extended photoperiod of 22 h per day resulted in as many as six generations of spring wheat and spring barley per year [ 27 ], whereas speed breeding combined with speed vernalization systems resulted in up to five generations of winter barley and winter wheat [ 29 ]. LEDs can also be used in horticulture and floriculture to improve crop yield, pre- and post-harvest quality, phytochemicals, and nutritional contents [ 25 ].…”

“… List of utilization examples of mentioned technologies [ 26 , 27 , 29 , 35 , 37 , 38 , 48 , 53 , 54 , 64 , 68 , 81 , 82 , 83 , 84 , 85 , 86 , 87 , 89 , 91 , 92 ]. …”