A suite of irrigation trials in summerfruit for yield and quality or irrigation best management practices

The Irrigation experiment at Tatura's Stonefruit Field Laboratory aims to Identify the combinations of irrigation levels and timing that will enable the late season nectarine variety September Bright to achieve maximum uniformity in fruit quality attributes.

Dr Mark O'Connell introduces the Nectarine, Open Tatura trellis, irrigation experiments.
  • 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: severe deficit irrigation to impose high level of water stress
  • 20 & 40: deficit irrigation to impose a 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: water stress restricts cell division, reduces fruit size and yield
  • Stage II of fruit development: water stress reduces vegetative vigour
  • Stage III of fruit development (early): water stress reduces fruit size and yield
  • Stage III of fruit development (late): water stress reduces fruit size and yield
2016/17 irrigation experiment

Regulated deficit irrigation (RDI) occurs during stage 2 of development. See Graph below.

Shoot and fruit growth graph

Results

Dr Mark O'Connell discusses some of the findings from the irrigation experiment in the following video (9 min, 37 sec)

Results from the Irrigation Experiment
Time series videos

Every few weeks photos were taken of each experiment, and produced into a video to show the resulting growth of tree canopies and fruit development.

Time series video

Photos of Nectarine, September Bright, on Open Tatura trellis, from 2015 to 2017

Plant Water Status Trial

Continuous detection of plant water status

This study aims to test plant-based sensors for their efficiency in determining nectarine water status in a modern high-density orchard.