Sound stress is an abiotic stress factor wherein the sound wave form affects the growth and development of plants as an alternative mechanical stress. To explore this, 10-week-old tomato (Solanum lycopersicum) plants were used in this experiment. The tomato plants were exposed to three different frequency values consecutively: 600 Hz in the first week, 1240 Hz in the second week and 1600 Hz in the third week. The decibel (dB) value was adjusted to 90 dB in the sound amplifier. At the end of the experiment, lycopene, vitamin C, total sugar, total acid and total phenol levels were analysed and pH and 0Brix were measured in tomato fruits. As a result, it was determined that as the sound frequency intensity level increased, the concentration of fruit parameters also increased: lycopene, vitamin C, total sugar, total acid and total phenol. The total phenol content, lycopene content and ascorbic acid of the tomato plants that were exposed to sound waves at different frequencies increased at a rate of 70%, 20% and 14%, respectively. According to the results of all measured parameters in tomato fruits, 1600 Hz has been determined the best of sound wave frequency value.
Keywords: Abiotic stress; Frequency (Hz); Fruit quality parameters; Solanum lycopersicum; Sound waves; Vegetable.