The effect of pre-sowing seed treatment with melatonin on cucumber productivity in protected soil conditions

The current paper has presented the results of the study aimed at a comprehensive assessment of the effect of presowing treatment of cucumber seeds with a melatonin solution on productivity and quality of the resulting yield in protected soil conditions. The trials were conducted over three years (2021–2023) on the F 1 cucumber hybrid Lel. There have been studied four treatment options, such as control (no treatment) and seed soaking in melatonin solutions at concentrations of 0.001%, 0.01%, and 0.1%. There have been assessed such key agronomic and biochemical parameters as time of seed germination, a beginning of key phenological phases (including the beginning of fruiting), productivity, yield structure, and commercial and biochemical characteristics of the fruits. The trials have shown that seed treatment with melatonin had a positive effect on plant growth and development. There was established an accelerated seed germination and earlier fruiting compared to the control. Furthermore, melatonin treatment has increased the number and size of fruits, as well as the proportion of marketable products. Depending on the solution concentration and the year of study, productivity increase ranged from 13.0% to 48.9%. There has been also found an improvement in the biochemical parameters of the fruits, such as increased content of dry matter and ascorbic acid, indicating improved nutritional value. The obtained results can be used to develop practical recommendations for increasing cucumber productivity and improving the quality of commercial fruits.