Allelic variation of TaWD40-4B.1 contributes to drought tolerance by modulating catalase activity in wheat.

Drought drastically restricts wheat production, so to dissect allelic variations of drought tolerant genes without imposing trade-offs between tolerance and yield is essential to cope with the circumstance. Here, we identify a drought tolerant WD40 protein encoding gene TaWD40-4B.1 of wheat via the genome-wide association study. The full-length allele TaWD40-4B.1 ^C but not the truncated allele TaWD40-4B.1 ^T possessing a nonsense nucleotide variation enhances drought tolerance and grain yield of wheat under drought. TaWD40-4B.1 ^C interacts with canonical catalases, promotes their oligomerization and activities, and reduces H ₂ O ₂ levels under drought. The knock-down of catalase genes erases the role of TaWD40-4B.1 ^C in drought tolerance. TaWD40-4B.1 ^C proportion in wheat accessions is negatively correlative with the annual rainfall, suggesting this allele may be selected during wheat breeding. The introgression of TaWD40-4B.1 ^C enhances drought tolerance of the cultivar harboring TaWD40-4B.1 ^T . Therefore, TaWD40-4B.1 ^C could be useful for molecular breeding of drought tolerant wheat.
(© 2023. The Author(s).)