Location: Hard Winter Wheat Genetics ResearchTitle: Cloning and characterization of a critical regulator for pre-harvest sprouting in Wheat Author
Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/10/2013
Publication Date: 7/2/2013
Publication URL: http://www.genetics.org/content/195/1/263.short
Citation: Liu, S., Sehgal, S., Li, J., Lin, M., Trick, H., Yu, J., Gill, B.S., Bai, G. 2013. Cloning and characterization of a critical regulator for pre-harvest sprouting in Wheat. Genetics. doi: 10.1534/genetics.113.152330. Interpretive Summary: Pre-harvest sprouting (PHS) of wheat causes annual crop losses of $1 billion. Consumers prefer white wheat varieties but they are more prone to PHS than red wheat. The mechanism of resistance to PHS in white wheat is not known. We found that a MOTHER OF FLOWERING TIME-like gene (TaMFT) regulates PHS resistance. Two nucleotide mutations in the coding region of the gene leading to mis-splicing and a truncated protein cause PHS. A DNA marker developed from the gene will facilitate effective deployment of TaMFT to protect grain yield and quality and extend the range of white wheat production.
Technical Abstract: Sprouting of grains in mature spikes before harvest is a major problem in wheat (Triticum aestivum) production worldwide. We cloned and characterized a gene underlying a wheat quantitative trait locus (QTL) on the short arm of chromosome 3A for pre-harvest sprouting (PHS) resistance in white wheat using comparative mapping and map-based cloning. This gene, designated TaPHS1, is a wheat homolog of a MOTHER OF FLOWERING TIME (TaMFT)-like gene. RNA interference-mediated knockdown of the gene confirmed that TaPHS1 positively regulates PHS resistance. We discovered two causal mutations in TaPHS1 that jointly altered PHS resistance in wheat. One GT-to-AT mutation generates a mis-splicing site, and the other A-to-T mutation creates a premature stop codon that results in a truncated non-functional transcript. Association analysis of a set of wheat cultivars validated the role of the two mutations on PHS resistance. The molecular characterization of TaPHS1 is significant for expediting breeding for PHS resistance to protect grain yield and quality in wheat production.