Radiation use efficiency increased over a century of maize (Zea mays L.) breeding in the US corn belt. (30th May 2022)

• Record Type: Journal Article
• Authors: Messina, Carlos D; Rotundo, Jose; Hammer, Graeme L; Gho, Carla; Reyes, Andres; Fang, Yinan; van Oosterom, Erik; Borras, Lucas; Cooper, Mark
• Editors: Lawson, Tracy
• Is Part Of: Journal of experimental botany. Volume 73:Number 16(2022)
• Page Start: 5503
• Page End: 5513
• Publication Date: 2022-05-30
• Subjects: Leaf angle -- maize -- plant breeding -- photosynthesis -- radiation use efficiency -- respiration; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erac212
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: In the absence of stress, crop growth depends on the amount of light intercepted by the canopy and the conversion efficiency [radiation use efficiency (RUE)]. This study tested the hypothesis that long-term genetic gain for grain yield was partly due to improved RUE. The hypothesis was tested using 30 elite maize hybrids commercialized in the US corn belt between 1930 and 2017. Crops grown under irrigation showed that pre-flowering crop growth increased at a rate of 0.11 g m –2 year –1, while light interception remained constant. Therefore, RUE increased at a rate of 0.0049 g MJ –1 year –1, translating into an average of 3 g m –2 year –1 of grain yield over 100 years of maize breeding. Considering that the harvest index has not changed for crops grown at optimal density for the hybrid, the cumulative RUE increase over the history of commercial maize breeding in the USA can account for ~32% of the documented yield trend for maize grown in the central US corn belt. The remaining RUE gap between this study and theoretical maximum values suggests that a yield improvement of a similar magnitude could be achieved by further increasing RUE. Abstract : Radiation use efficiency increased over a century of maize breeding, explaining ~32% of yield improvement. Radiation use efficiency has not reached potential values (so further yield gains are possible).