Transformational agronomy by growing summer crops in winter: water productivity of dryland sorghum on the Liverpool Plains, NSW

Abstract

Early sown sorghum is a viable alternative for the Liverpool Plains of NSW. It is currently unknown if the longer vegetative period created by sowing into sub-optimal soil temperatures could affect water productivity. Water use was measured on an early (Agitator) and a late (MR Buster) maturing hybrid, sown in early and late spring and summer in 2018 and 2019 at 30, 60 (standard practice) and 120 thousand plants/ha. Crops sown very early into cooler soil conditions had lower water use than those sown at early and normal sowing times. There was a significant impact of time of sowing on grain yield, which was seasonally dependent. Water productivity for MR Buster was higher when grown at 30,000 plants/ha compared to the standard density and higher density. For Agitator, earlier sowing reduced water productivity. The potential of early sowing to increase yield and water productivity of sorghum needs assessment under additional seasons and environmental conditions.