The Effect of Application of Ethephon to Processing Tomato Plants on the Chemical Composition of Fruits

Ethephon is used to accelerate fruit ripening on plantations with well-developed plants which have formed a large quantity of fruits. The aim of the study was to determine the effect of ethephon on the chemical composition of the fruits of seven cultivars of processing tomato (‘Rumba’, ‘Hubal’, ‘Sokal’ F1, ‘Mieszko’ F1, ‘Polset’ F1, ‘Hysioux’ F1 and ‘AF1120’ F1), applied to the plants when most of the fruits had reached the mature-green stage. The study was conducted during three consecutive years, characterized by different weather conditions. Meteorological elements, i.e. air temperature and precipitation totals, were monitored in the experimental station in Mydlniki, near Krakow, Poland. Ethephon was found to have a beneficial effect on the content of extract and soluble sugars of the harvested tomatoes and on their acidity. Dry matter and lycopene levels were not dependent on the use of this compound, while the ascorbic acid content was reduced by the procedure. The chemical composition of the tomato fruits differed significantly in consecutive years of the study, which confirmed the weather impact on fruit quality and on the varied responses of different cultivars to use of ethephon. The tested cultivars were also compared in terms of their suitability for processing. The ‘Hubal’ cultivar had the highest content of dry matter, extract, soluble sugars of all the cultivars tested. The highest level of lycopene was noted for the tomatoes of the ‘Rumba’ and ‘Sokal’ F1 cultivar, ascorbic acid of the ‘Rumba’ and the highest acidity for ‘AF 1120’ F1.