Wheat Water-Soluble Carbohydrate Remobilisation under Water Deficit by .

Fructan 1-exohydrolase (1-FEH) is one of the major enzymes in water-soluble carbohydrate (WSC) remobilisation for grains in wheat. We investigated the functional role of , , and isoforms in WSC remobilisation under post-anthesis water deficit using mutation lines derived from the Australian wheat variety Chara. F1 seeds, developed by backcrossing the , , and mutation lines with Chara, were genotyped using the Infinium 90K SNP iSelect platform to characterise the mutated region. Putative deletions were identified in mutation lines encompassing the genomic regions. Mapping analysis demonstrated that mutations affected significantly longer regions than the target gene regions. Functional roles of the non-target genes were carried out utilising bioinformatics and confirmed that the non-target genes were unlikely to confound the effects considered to be due to the influence of gene functions. Glasshouse experiments revealed that the mutation line had a slower degradation and remobilisation of fructans than the and mutation lines and Chara, which reduced grain filling and grain yield. Thus, plays a vital role in reducing yield loss under drought. This insight into the distinct role of the isoforms provides new gene targets for water-deficit-tolerant wheat breeding.