Evaluation of Compact Growth Habit Tomato Breeding Lines for the Florida Mature-green Fresh Market

摘要

Compact growth habit (CGH) tomatoes (Solatium lycopersicum) are determinate plants, with shortened internodes and strong side branching due to the brachytic gene (br). They grow prostrate or upright due to unidentified gene(s). Compact growth habit tomatoes do not require staking, tying, or pruning, and can potentially be mechanically harvested, lowering Florida tomato production costs. Therefore, the objective of this study was to evaluate two plant populations (PP) and six CGH tomato breeding lines(BL) from the University of Florida Tomato Breeding Program (UF-TBP) on growth, yield, and postharvest fruit quality. The experiment was conducted in a commercial tomato field in Immokalee, FL, during Spring 2013, using a split-plot design with four replications. Tomato BL 8914,8915,8916, 8916a and b, and 8834 were planted as single and double rows with a plant spacing of 24 and 19 inches for a PP of 3630 and 5082 plants/acre, respectively. Tomato plant growth was measured as plant height, diameter, and canopy volume at 60 and 90 days after transplanting. Fruit were harvested twice at mature-green stage and graded into marketable yield sizes and unmarketable by defect categories. Postharvest evaluation included fruit firmness (as fruit deformation), and skin color. Single row produced larger plants than double row, but PP did not affect marketable yields. First and total season marketable harvests ranged from 496 to 1104 and 928 to 1915 boxes/acre, respectively. Breeding line 8916 had the highest total extra-large fruit yield; however BL 8915 had the highest total large and medium fruit yields. Unmarketable fruit ranged from 22% to 31% of the total season harvest and the most common fruit defects were sunscald and off-shape. Fruit firmness and skincolor ranged from 2.12 to 2.92 mm and 5.69 to 5.97, respectively. However, postharvest differences between PP and among BL were not of commercial importance. Based on one year of data, CGH tomato BL produced lower total season marketable harvest than currently-grown staked-upright tomato varieties. Nonetheless, CGH tomatoes total production cost can potentially be lower than staked-upright varieties, thus CGH may be a viable option for the Florida mature-green fresh-market industry.