Hand versus Mechanical Harvest of Fresh-market Grape Tomatoes

Grape tomato (Solanum lycopersicum) sales represented 22% of the U.S. fresh tomato supermarket segment in 2013, with a value in excess of $100 million. Fruit is typically hand-harvested each 3 to 4 days during the season; thus, labor constitutes a significant portion of production costs. We investigated the potential for utilizing the Model 2000 Blueberry Harvester (BEI Inc.) for mechanical harvest, given the similarity of plant architecture between blueberry bushes and staked grape tomatoes. This over-the-row harvester has two vertical shafts securing harvesting tines (10-mm diameter) with protective coating and adjustable rotation speed. Detached fruit fall onto “fish-scale” catch plates and are conveyed to field lugs at the rear of the unit. Fifty-plant plots (30.5 m) were harvested either by hand (two plots) or mechanically (two plots) from a commercial field in west-central Florida in June 2014. Over a 3-wk period, hand-harvests were done every three to four days (4 harvests, total), and mechanical harvests were done weekly (3 harvests, total). Harvested fruit at full orange and red maturity stages were sorted and stored in rigid clamshell containers (1 lb capacity) for 4 d at 15°C then transferred to 20° for 2 d. Non-recovered fruit were considered those that either remained on the plant or fell to the ground during harvest. Hand harvesting recovered 96% of marketable fruit from plots, whereas mechanical harvesting recovered 56%. The amount of immature fruit that was harvested mechanically was 137% higher than hand harvested (5,196 kg/ha compared to 2,188 kg/ha, respectively). After 6 d storage there were no significant differences in tomato quality due to maturity stage or harvest method. Appearance was consistently rated as field fresh; there was evidence of bruising, shrivel or decay, and firmness averaged 265 g-f/mm. Soluble solids content ranged from 6.40 to 7.07 ^oBrix and citric acid levels ranged from 0.38 to 0.47. Mechanical harvest shows promise for end of season, when removal of immature fruit is not an issue.