2018 ASHS Annual Conference

A modified over-the-row (OTR) harvester (Oxbo Model 7240) with experimental-catch surfaces was used for harvesting ‘Duke’ and ‘Draper’ blueberry in Oregon and ‘Elliott’ and ‘Aurora’ blueberry in NW Washington. All plants were hand-harvested once and then machine harvested (MH) about 7 days later. The modifications to the harvester included a soft intermediate surface over the plastic conveyor belt and hollowed out plastic catch plates (e.g. tennis racket head) to which neoprene sheet (SCS) installed on one side and on the other side a canvass like intermediate surface over the conveyor belt and standard plastic catch plates (HCS). In Oregon, handheld pneumatic shakers operated by workers standing on a platform and in Washington a totally mechanical Orbirotor picking system were used. Harvested fruits were run through commercial packing lines with fresh pack-out recorded and fresh fruit quality evaluated during various length of cold storage. The fresh pack-out for ‘Draper’ and ‘Duke’ were at 73% and 83%, respectively, and no difference was noted between MH with SCS and HCS. ‘Draper’ and ‘Elliott’ fruit firmness was the highest with hand harvesting, followed by MH with SCS and HCS which had the same firmness. Hand-harvested ‘Aurora’ had the same fruit firmness as MH with SCS. After 2-4 weeks cold storage, fruit firmness for both ‘Draper’ and ‘Duke’ decreased in MH fruits. For ‘Elliott’ and ‘Aurora’, fruit firmness was the same among harvesting methods after 2 weeks of cold storage. ‘Aurora’ fruit had similar bruise ratings between hand harvesting and MH with SCS, while ‘Elliott’ fruit showed more bruise damage by MH with both SCS and HCS than in hand harvested fruit. Postharvest bruise ratings of ‘Elliott’ fruit were not affected by harvesting method, while the bruise ratings of ‘Aurora’ was lower in hand harvested fruits compared to MH with both SCS and HCS. Although our studies showed slightly lower fresh market blueberry pack-outs (%), increased bruise damage, and loss of firmness in fruit harvested by the experimental MH system compared to the hand harvested fruit, these findings were much better than those achieved by commercial OTR harvesters. We demonstrated that fresh market blueberry quality is achievable by using an OTR harvester with softer fruit catching surfaces.