Emmer wheat (Triticum dicoccon Schrank) improves water use efficiency and yield of hexaploid bread wheat

Emmer wheat (Triticum dicoccon Schrank) is a potential source of new genetic diversity for the improvement of hexaploid bread wheat. Emmer wheat was crossed and backcrossed to bread wheat and 480 doubled haploids (DHs) were produced from BC₁F₁ plants with hexaploid appearance derived from 19 crossses. These DHs were screened under well-watered conditions (E1) in 2013 to identify high-yielding materials with similar phenology. One-hundred and eighty seven DH lines selected on this basis, 4 commercial bread wheat cultivars and 9 bread wheat parents were then evaluated in extensive field experiments under two contrasting moisture regimes in north-western NSW in 2014 and 2015. A significant range in the water-use-efficiency of grain production (WUE_Grain) was observed among the emmer derivatives. Of these, 8 hexaploid lines developed from 8 different emmer wheat parents had significantly improved intrinsic water-use-efficiency (WUE_intr) and instantaneous water-use-efficiency (WUE_i) compared to their bread wheat recurrent parents. Accurate and large scale field-based phenotyping was effective in identifying emmer wheat derived lines with superior performance to their hexaploid bread wheat recurrent parents under moisture stress.