The Orchard Architecture Dedicated for Mechanical Harvesting of Dessert Plums and Prunes

Abstract

Two plum cultivars ‘Record’ and ‘Empress’ and one prune cultivar ‘Common Prune’ were planted in spring 2014, spaced at 4.5 × 1.5 × 2.0 m, to be trained to the “Y”- and “V”-trellising systems for mechanical harvesting of dessert fruits with a canopy-contact harvester. The applied trellising systems were compared with the standard central leader system at the same spacing. Trellised trees showed a tendency to grow less well than leader-trained trees, but during the four years of training, they created a higher canopy volume than the control trees because of their spreading form. Trellised trees were able to give yields comparable to those of standard trees. Light distribution within the tree canopy was acceptable in all the training systems. After 4 years of training, the trees were suitable for mechanical harvesting. The effectiveness of mechanical harvesting varied from 85% to 90%. The quality of the fruits harvested with a canopy-contact harvester was comparable to that of manually picked fruits. The consumption of quality of fruits after mechanical harvesting rated on a 5-grade scale was 0.5 grade lower than that of manually harvested fruits. These fruits were acceptable in the local fruit market. Mechanical harvesting was 10–30 times faster compared to manual picking. The cost of the trellising system calculated per 1 ha was 2.0 times higher than that of the standard system.

Comparison of the yielding of plum, sour cherry, and sweet cherry trees trained to a trellis for mechanical harvesting of fruit with those trained to a leader

“…Pol. Hortorum Cultus, online first, https://doi.org/10.24326/ asphc.2023.4638 yield confirm the previous research of many authors [Ampatzidis et al 2012, Day et al 2013, Larbi and Karkee 2014, He et al 2015, Mika et al 2016]. In the fourth year after planting the trees (2017), fruit yields were low due to a cool spring and frosts in April.…”

“…In 2008, at the Institute of Horticulture -National Research Institute in Skierniewice, attempts were initiated to machine--harvest dessert fruit from trees shaped in the form of a horizontal crown, with only one layer of branches spread in the shape of the letter 'T'. In that experiment, a task was undertaken to mechanically harvest plums for dessert use from trees planted at high density [Mika et al 2016]. The thickness of the canopy of the trees formed in this way was about 1.5 m along the vertical section.…”

“…During the combine harvest, the fruits were lifted off the tree crowns and fell onto a mobile conveyor from a short distance, a maximum of 1.5 m, so that they did not bruise as much as during harvesting with a large harvester for processing. In that experiment, in the years 2008-2015, two systems of training the canopy of 'Elena' plum trees were compared: trees in the form of a horizontal T-shaped crown and tall trees in a standard conical form [Mika et al 2016].…”