Irrigated sunflowers remain a small component of total Australian sunflower production. In northern NSW sunflower irrigation is conducted on either flood or under pivot irrigation systems.
In the past two years increased areas have been sown to irrigated sunflower in southern NSW and Victoria.
This expansion has highlighted that previous research on irrigated sunflowers in Australia is extremely limited and was most recently conducted in the 1970’s.
Sunflower growers and advisors need access to an information package to assist in the decision making process around agronomic issues such as plant population, nitrogen rates and number and timing of irrigations.
Preliminary trials have been conducted at the Liverpool Plains Field Station, Breeza, northern NSW under a raised bed flood irrigation system in the 2011/12 and 2012/13 seasons.
These two trials using the monounsaturated hybrid Ausigold 62 compared nil and one in crop irrigation. In the 2012/13 season varying plant populations of 30, 40 and 50,000 plants/ha and varying nitrogen rates of 0, 50, 100 and 200 kg /ha were added as additional treatments. Sunflower water use was measured using a neutron moisture meter.
Both seasons received significant in crop rainfall, allowing only one irrigation application, however from the 2011/12 season the effect of delaying the timing of this one irrigation from early budding to early flowering resulted in a significant decline in yields of 1 t/ha. Results from the 2012/13 season will be available shortly.
This research is the start of an irrigation information package for sunflower growers and advisors in the northern grains region, a new phenomenon in the new millennium.