Key research findings

Drip irrigation was able to meet pear crop water requirement and provide substantial improvement in water use efficiency in young trees. Water savings of approximately 35 % over the first four years after planting were achieved by using drip irrigation compared with microjet irrigation. Drip irrigation did not result in delayed establishment of young pear trees. In fact, drip irrigation increased early yields by 167 %. Pulse irrigation with microjets is not advised for pear trees in their first-leaf because of increased water losses via evapotranspiration, which decreases soil water availability and increases the risk of water stress. Once trees cropped, pulse irrigation improved fruit size. Combined with a trend for increased fruit number (not statistically significant), the increased fruit size contributed to 23 % greater yield in Pulse than Standard irrigation treatments in the sixth-leaf. Root pruning of young pear trees did not affect tree vigour or increase precocity.

Video transcript

This is our irrigation experiment in our profitable pears project. What we're looking at here is comparing MICRO JET irrigation, which I'm looking at right in front of me here, with drip irrigation. Now, we're not only just looking at those two types of irrigation systems, we're also looking at the Irrigation frequency. So on both those treatments we're comparing very frequent irrigation with a standard interval irrigation. So, in other words on a drip we're actually irrigating multiple times a day, maybe two or three times per day and comparing that with an irrigation, a drip irrigation that's perhaps every couple of days. The other treatment, that we're also looking at in this experiment, is we've included root pruning. So we're comparing with and without root pruning. The idea of the root pruning is to try and stimulate these trees to come into fruit production a lot earlier. So by cutting those roots off, we are affecting the generation of hormones in the tree, which hopefully is stimulating leaf buds to become flower buds and start cropping early in the life of the trees.

Microjet Irrigation

Irrigation Experiments

This experiment will compare the effectiveness of two different irrigation systems, micro-jet and drip irrigation.
In this experiment, there will also be comparison between a multiple day irrigation frequency and a standard interval irrigation for both drip and mico-jet systems.

Root Pruning

Root Pruning Experiments

This experiment will look at the effects of root pruning, compared to trees without root pruning, to determine if root pruning stimulates trees to come into fruit production earlier, and determine how much earlier production can be achieved.

Summary results - Irrigation for young pears

Summary of the effects of drip irrigation and irrigation interval in newly planted pear orchards on irrigation requirement, water status, growth and yield.

Key messages:

35% less irrigation was applied in the drip treatments
Drip irrigated trees in Year 1 were less stressed
Frequently irrigated trees in Years 3 and 4 were less stressed
There was no effect of drip irrigation or irrigation interval on young tree growth
Yield increased by 167% under drip irrigation attributed to fruit number
Spur flower cluster number was higher under drip irrigation
Fruit size was greater under frequent irrigation

Summary results - Irrigation for young pears

^{This project, AP12002 Profitable Pears: Maximising productivity and quality of new pear varieties, is funded by Agriculture Victoria with co-investment from Horticulture Innovation Australia Limited using the apple and pear levy and funds from the Australian Government}

Key research findings

Experimental design

Irrigation Experiments

Root Pruning Experiments

Summary results - Irrigation for young pears