Fino lemon clones compared with the lemon varieties Eureka and Lisbon on two rootstocks in Murcia (Spain)

Six clonal selections of the autochthonous Spanish lemon tress cv. Fino, named Fino 46, Fino 47, Fino 48, Fino 49 and Fino 77, and two foreign varieties Eureka and Lisbon (Citrus limon (L.) Burm. f) grafted on sour orange (C. auramtium L.) and Citrus macrophylla (C. macrophylla Wester) rootstocks were studied in Murcia (Spain). The fruit were harvested for 6 years, and fruit quality and tree size were evaluated after the sixth harvest. Fino 49, Fino 77 and Lisbon trees produced the highest cumulative yield. However, Eureka trees on macrophylla had the highest yield efficiency (cumulative yield/trunk cross-sectional area (TCSA)) due to its small TCSA. There were few differences between Fino group and Lisbon as regards fruit quality; however, Eureka trees on macrophylla produced smaller fruit with a higher concentration of total soluble solids (TSS) and titratable citric acid (TA) than the other varieties. Macrophylla was a better rootstock than sour orange for lemon trees since lemon trees grafted on macrophylla had higher cumulative yield and yield efficiency than those on sour orange. However, sour orange induced the highest TSS and TA in all lemon varieties evaluated.