Quality Parameters of Spanish Lemons with Commercial Interest.

The Spanish Mediterranean region concentrates the largest producers of lemons (Citrus limon Burm. f.) at the national level where the 98.4% of the cultivated area of lemons corresponds to the varieties "Verna" and "Fino". In this study, the morphological and chemical variations of the fruits obtained in five variety/rootstock combinations were investigated in order to determine the influence and impact of the rootstock on the physicochemical properties of the fruits. The assay was carried out using three lemon varieties ("Fino 95", "Fino 49" and "Verna") grafted onto two different rootstocks (Citrus macrophylla and Citrus aurantium). The varieties were selected due to be consolidated commercial varieties, while the rootstocks are the most commonly used in the world. Both the morphological characteristics of the fruits (colour, weight, size) as well as their physicochemical characteristics (total soluble solids, titratable acidity, maturity index, antioxidant activity, sugars, and organic acids) were evaluated. Based on the results, the lemons with the best physicochemical and the best compositional characteristics were obtained in the "Fino 95" and "Fino 49" lemons grafted onto C. aurantium rootstock presented the highest quality fruits.

Determination of the Volatile Profile of Lemon Peel Oils as Affected by Rootstock.

Citrus limon (L.) Burm is an important crop that grows between latitudes 30° North and 30° South, the main producers being China, the USA, Mexico, India, Brazil, and Spain. In Spain, lemon grows mainly in Mediterranean areas such as Murcia, Valencia, and Andalucía. The most cultivated varieties are "Fino" and "Verna". In this study, five varieties of lemon, "Verna", "Bétera", "Eureka", "Fino 49", and "Fino 95" were evaluated on different rootstocks: three new Forner-Alcaide ("FA13", "FA5", "FA517"), Citrus macrophylla, Wester, and Citrus aurantium L. Hydrodistillation was used to obtain essential oil from fresh peels and then the volatile profile was studied by gas chromatography-mass spectrometry (GC-MS). A total of 26 volatile compounds were identified, limonene being the main one followed by ß-pinene, γ-terpinene, sabinene, and α-pinene. The results revealed that Forner-Alcaide rootstocks ("FA5" > "FA517" > "FA13") proved to be the best rootstocks for the aroma quality as they led to high volatile contents, followed by C. aurantium and C. macrophylla. Among the other varieties, the most aromatic one was "Eureka". The whole trend was as follows (in decreasing order): "Eureka" > "Bétera" > "Fino 95" > "Verna" > "Fino 49".