Open Access122 Processing Tomato Fruit Firmness, Color Uniformity, and Peeling Response to Ethephon Sprays
Author(s) -
Mark A. Bennett,
David M. Francis,
Elaine M. Grassbaugh
Publication year - 2000
Publication title -
hortscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.518
H-Index - 90
eISSN - 2327-9834
pISSN - 0018-5345
DOI - 10.21273/hortsci.35.3.410b
Subject(s) - ethephon , titratable acid , cultivar , horticulture , ripening , yield (engineering) , chemistry , mathematics , biology , materials science , ethylene , biochemistry , metallurgy , catalysis
Ethephon (2-chloroethyl phosphonic acid) has been widely used under field conditions as a growth regulator to trigger the ripening of processing tomatoes prior to mechanical harvesting. Recent interest in whole-peeled and diced tomato products has raised questions about ethephon rates, and possible split applications for top quality. This 3-year field study tested two commercial cultivars of processing tomatoes (`OH8245' and `P696') and the effect of various ethephon applications on fruit firmness, color uniformity, and peeling variables. Transplants were established in mid to late May of 1996–1998 on raised beds in single rows at the OSU/OARDC Veg. Crops Branch in Fremont, Ohio. Ethrel applications for each cultivar were: 0, 0.58, 0.58 × 2 applications, 1.17, 1.17 × 2 applications, 1.75, 2.34, 4.68, and 7.02 L·ha –1 . Fruit were tested for firmness, color uniformity, pH, titratable acids, and soluble solids. Samples from ethephon treatments of 0, 1.17 × 2 applications, 2.34, 4.68, and 7.02 L·ha –1 were peeled and canned for color inspection and firmness after 18 months storage. Three-year data for red fruit yield showed a typical response to increasing amounts (0 to 7.0 L·ha –1 ) of applied ethephon. While high rates (4.7 or 7.0 L·ha –1 ) gave some of the highest red fruit yields, and the greatest percent red fruit values, high rates were also linked with among the lowest fruit solids values. Split application comparisons showed little influence on quality variables examined in this study. However, chroma values were improved (more vivid color) when 2.3 L·ha –1 was applied vs. 1.17 L·ha –1 applied twice. Split applications also tended to produce softer fruit. Our results suggest that single ethephon applications of 1.17 to 2.34 L·ha –1 provide optimal fruit ripening and quality under midwestern U.S. conditions.