At the Dalbeg experiment, at every irrigation cycle, the half irrigation
treatment received a volume of water similar to ~50% of the full
irrigation treatment. The water stress treatments received only one irrigation
at the beginning of each crop cycle only to establish the crop.
The timing and severity of water stress depended on rainfall as well
as irrigation. The annual rainfall in the dry tropical region of North
Queensland occurs during summer and early autumn (December to
March), and dry weather prevails during the rest of the period. Therefore,
in non-rainfed locations, the irrigation treatments were applied to produce
contrasting water availability during spring (September–November
for early growth) and autumn/winter (March–August for late growth).
All the treatments received adequate rainfall during mid to late summer
(December–February), and hence no irrigation was necessary