Effects of wetted soil volume on young pear trees
Pear orchards in the Goulburn Valley, Australia, are being re-developed and expanded using better varieties and modern planting systems. Efficient irrigation systems, like drip, are an integral component of these new orchards. However, drip is rarely used in pear orchards in the region and many existing orchards use microjet irrigation systems. Soil wetting patterns from drip systems are much smaller than microjet systems and this may impact on the performance of young pear trees. A field experiment was established in 2012 to investigate the effects of wetted volume (imposed by the combination of irrigation system and irrigation frequency) on irrigation requirements, tree growth and water status. Drip and microjet irrigation at standard and pulse intervals were compared using a new red-blushed pear cultivar (Pyrus communis L. 'ANP-0118') grafted to BP-1 rootstock. No evidence was observed that a reduction in horizontal wetted volume (i.e., drip irrigation) impacted leader growth, pruning dry weight, radiation interception, and midday stem water potential and leaf conductance. However, a shallow broad wetted volume (microjet irrigation at frequent interval) made trees susceptible to water stress and trees exhibited a reduction in growth. Approximately 40% less irrigation was applied in the drip irrigation treatments resulting in a water saving of 2.1 ML ha-1 y-1.
McClymont, L. and Goodwin, I. (2016). Effects of wetted soil volume on young pear trees. Acta Hortic. 1130, 479-484
stem water potential, leaf conductance, canopy radiation interception, pulse irrigation, wetting pattern