
%0 Journal Article
%A Regan, K. L. 
%A Siddique, K. H. M. 
%A Tennant, D. 
%A Abrecht, D. G. 
%T Grain yield and water use efficiency of early maturing wheat in low rainfall Mediterranean environments
%J Australian Journal of Agricultural Research
%D 1997/06/04
%V 48
%N 5
%P 595-604
%K early maturity, phenology, harvest index.
%R https://doi.org/10.1071/A96080
%U https://www.publish.csiro.au/paper/A96080 
%X Wheat cultivars with very early maturities appropriate for late sowings in low-rainfall (&#60;325 mm) short-season environments are currently unavailable to wheat growers in the eastern margin of the cropping region of Western Australia. A demonstration that very early-maturing genotypes can out-perform current commercial cultivars would open new opportunities for breeding programs to select very early-maturing, high- and stable-yielding cultivars for these environments. Six field experiments were conducted over 4 seasons at 2 low-rainfall sites in Western Australia to investigate crop growth, grain yield, and water use efficiency of very early-maturing genotypes compared with current commercial cultivars when sown after 1 June. Very early-maturing genotypes reached anthesis up to 24 days (328 degree-days) earlier than the current cultivars, produced less leaves, had similar yields and dry matter, and maintained high water use efficiencies. On average across seasons and locations the very early-maturing genotypes (W87&#8211;022&#8211;511, W87&#8211;114&#8211;549, W87&#8211;410&#8211;509) yielded more than the later maturing cultivars Gamenya and Spear (190 v. 160 g/m2) but they were similar to the early-maturing commercial cultivars Kulin and Wilgoyne (191 g/m2). Very early-maturing genotypes generally had a higher harvest index and produced fewer spikelets, but heavier and more grains, than Kulin and Wilgoyne. There were only small differences in total water use between very early-maturing genotypes and commercial cultivars; however, very early-maturing genotypes used less water in the pre-anthesis period and more water in the post-anthesis period than the later maturing genotypes, and hence, experienced less water deficit during the grain-filling period. This study indicates that there is a role for very early-maturing genotypes in low-rainfall short-season environments, when the first autumn rains arrive late (after 1 June). 
