Influence of Growing Substrate and Rootstock on the Physicochemical Properties of Lemons

Lemons are regarded as one of the most important species in the world due to its high level of bioactive compounds. Lemon juice is credited with direct health benefits due to its antimicrobial, antioxidant, antiviral, and anti-inflammatory activity. Their economic importance stems not only from their fresh consumption but also from their applications in various industries such as medical, pharmaceutical, and food. However, the chemical and nutritional composition of lemons is not constant and can be influenced by external factors, including variety, weather conditions, and crop management. Therefore, the main objective of this study was to determine the compositional variations of the fruit, which is essential to define its potential use. The rootstock and growing substrate were two controlled factors that were evaluated in relation to the physicochemical properties of the 'Verna' lemon. Ninety lemon trees were grown on three different rootstocks and three different culture mediums. Lemon trees cultivated with a 50% sediment/peat mix substrate showed a higher total production (590 lemons and 90.53 kg) than those cultivated with 75% marine sediment, which resulted in an 80% lower production. Citrus aurantium's output was greatly outperformed by Citrus macrophylla and Citrus aurantium/Citrus sinensis rootstocks. All the fruits presented a predominantly yellow color appropriate for the market (0 < CI < +5), and nutritional and chemical parameters were consistent with data reported for 'Verna' clones. All of the lemons obtained, both fresh and processed, were suitable for marketing and consumption. The findings showed that the studied variables have limited influence on the quality parameters of lemon fruits but could confirm the potential of marine sediment as a culture substrate.