Table 2 Changes made to the standard simulation for the nine treatments.

N-fertilisation

Apply different rates of N depending on whether Yw is low, medium or high:

If Yw ≤3.2 t ha⁻¹, apply 22.5 kgN ha⁻¹ at sowing only.

If Yw >3.2 t ha⁻¹ and Yw ≤4.4 t ha⁻¹, apply 45 kgN ha⁻¹ at sowing only.

If Yw >4.4 t ha⁻¹, apply 67.5 kg N ha⁻¹ at sowing only.

Soil N and surface organic matter are not reset

Initial soil N 124 kgN ha⁻¹ distributed through layers of the profile

Plants 50

Sowing density changed to 50 plants m⁻²

Plants 75

Sowing density changed to 75 plants m⁻²

Plants 100

Sowing density changed to 100 plants m⁻²

Plants 125

Sowing density changed to 125 plants m⁻²

Sow-1

Northern sites

Sow if rain ≥25 mm over 3 days and PAW ≥30 mm from 26 April- to 15 July.

Southern sites

Sow if rain ≥25 mm over 3 days regardless of soil moisture from 26 April to 15 July.

Sow-2

Northern sites

Sow 2 weeks after rain ≥15 mm over 3 days and PAW ≥30 mm from 26 April to 15 July.

Southern sites

Sow 2 weeks after rain ≥15 mm over 3 days regardless of soil moisture from 26 April to 15 July.

If sowing criterion is not met by 15 July, sow 2 weeks after 15 July.

Sow-3

Sow using highest yielding sowing date from analysis of crops sown every 7 days from 5 April to 21 June using highest yielding cultivar.

Fallow

To simulate the effect of weeds during the fallow, plant available water was reduced by up to 30 mm on 25 April by removing 70% of the plant available water from each layer starting from the top layer