- Nectarine cv. September Bright with Rootstock: Elberta
- Planted winter 2014 in Open Tatura tree training at a density of 2222 trees/ha
The experiment has three irrigation levels and four irrigation application timings as treatments.
The irrigation levels (% of tree evapotranspiration), applied using drip irrigation, are:
- 0: extreme deficit irrigation to impose high level of water stress
- 20 & 40: deficit irrigation to impose severe and moderate level of water stress
- 100: control irrigation, crop water requirement to maximise yield
The experiment has four irrigation application timings and likely crop responses:
- Stage I of fruit development: cell division (rapid fruit growth) - water stress restricts cell division, reduces fruit size and yield
- Stage II of fruit development: pit hardening (slow fruit growth, maximum vegetative growth) - water stress reduces vegetative vigour
- Stage IIIa of fruit development (early): cell expansion - water stress reduces fruit size and yield
- Stage IIIb of fruit development (late): cell expansion (sugar accumulation, chlorophyll degradation) - water stress reduces fruit size and yield
Table 1: Irrigation experimental treatments
Regulated deficit irrigation (RDI) occurs during stage 2 of development. See Graph below.