Effects of water deficit on yield of wheat and triticale

Abstract

The yield response of two commercial bread wheat cultivars and one triticale to water deficits imposed before anthesis, after anthesis, or during the complete life cycle was studied in a large bin (55l) experiment under rain shelters at Camden, New South Wales. Water status was managed by weekly water replacement to allow withdrawal to 25 and 0% remaining available soil water for the well-watered and deficient treatments, respectively. The three cereals performed similarly under continuously well-watered conditions (89.9, 91.1, and 100.7 g grain/bin) but under continuous water deficit the triticale produced significantly less than the bread wheats (31.2 cf 53.1 g grain/bin), respectively. The reason for this was the greatly reduced yield per plant from tillers in the triticale. Efficiency of water use over the complete life cycle for grain production was greater for the wheats than for the triticale (1.351 cf 0.954 g l-1, respectively), and maximum efficiency resulted from provision of adequate water before anthesis (an average of 1.310 g l-1 for treatments well watered before anthesis, cf an average of 1.130 g l-1 for those growing under water deficits). Post-anthesis water status had no significant effect on these values.