Effects of melatonin on sprouts, microgreens and baby leaves of parsley and cilantro cultivated under organic systems

Parsley (Petroselinum crispum Mill.) and cilantro (Coriandrum sativum L.) are commonly utilized in the food industry for various dishes, as ready-to-eat products, as well as in the cosmetics and pharmaceutical industries. This trial aimed to investigate the effects of melatonin on the morphometric characteristics and biochemical profile of parsley and cilantro at different stages of growth, including sprouts, microgreens, and baby leaves. The seeds were sown in a cold greenhouse located in Catania (Sicily) at the beginning of December 2022, following organic farming practices. The plantlets were collected at different growth stages and were characterized for their weight, the hypocotyl length, the dimensions of the cotyledon, the number of true leaves and the length and width of the true leaves. The study also determined the total phenolic compounds, antioxidant capacity, total flavonoid compounds, and ascorbic acid. The results showed notable differences among the different experimental factors examined. The morphometric characteristics of the plants varied in relation to the treatment, showing differences based on the genotype. The melatonin application (M100) resulted in an increase in total phenolic content, antioxidant capacity, and total flavonoid content, while the amount of ascorbic acid decreased with the application of exogenous melatonin. These findings are valuable for enhancing the advantages of innovative food products and recommending their usage.